Effectiveness of fluorides in root caries prevention, Department of Veterans Affairs (2009-2018)

AIMS

The aim of this study was to examine the effectiveness of topical fluorides in prevention of root caries-related treatment in high caries risk Veterans.

METHODS

This retrospective analysis of longitudinal data examined the effectiveness of professionally applied or prescription (Rx) fluoride treatment, in VHA clinics from FY 2009-2018. Professional fluoride treatments included 5% Sodium Fluoride (NaF) varnish (22 600 ppm fluoride), 2% NaF gel/rinse (9050 ppm fluoride), and 1.23% APF gel (12 300 ppm fluoride). The Rx for daily home use was 1.1% NaF paste/gel (5000 ppm fluoride). Outcomes studied were new root caries restorations or extractions and percent of patients with treatment over 1 year. Logistic regressions were adjusted for age, gender, race, ethnicity, chronic medical or psychiatric conditions, number of medication classes, anticholinergic drugs, smoking, baseline root caries treatment, preventive care, and time between first-last restoration in the index year.

RESULTS

Root caries at baseline was associated with a high risk for new root caries. Veterans without root caries during the index year who received a fluoride gel/rinse intervention were 32-40% less likely to receive caries-related treatment for root caries during the follow-up period. Once Veterans had root caries, fluorides did not exhibit a positive effect.

CONCLUSION

In older adults with high caries risk, early fluoride prevention is key, before root caries requires treatment.

Mechanism of dentin hardness measurements using a dentin hardness measuring device with a light-emitting diode

Significance

Managing caries is imperative in a rapidly aging society. Current diagnoses use qualitative indices. However, a quantitative evaluation of hardness in a clinical setting may lead to more accurate diagnoses. Previously, hardness meter using indenter with light for tooth monitoring (HAMILTOM) was developed to quantitatively measure tooth hardness. Herein, the physical interpretation of dentin hardness measured using HAMILTOM and the dentin hardness measurement mechanism are discussed.

Aim

This study evaluates the mechanism of dentin hardness measurements using HAMILTOM physically and compare the invasiveness to dentin by HAMILTOM with those using a dental probe for palpation.

Approach

Eleven bovine dentin samples were used to create caries models. HAMILTOM measured the dark areas, and its indentations were observed using scanning electron microscopy. Also, its invasiveness was evaluated by comparing the results with those from dental probe palpation.

Results

The indentation areas were smaller than the dark areas in HAMILTOM, which may be due to exuded water from the dentin sample and the elastic recovery of dentin sample. Additionally, the dental probe indentation was deeper than the HAMILTOM indentations.

Conclusions

The results demonstrate that the indentation areas were smaller than the dark areas measured by HAMILTOM, which might contain the influence of exuded water and the deformation of dentin sample. Also, HAMILTOM is less invasive than dental probe palpation. In the future, HAMILTOM may become a standard hardness measuring method to diagnose root caries.

Clinical parameters that affect performance and patient satisfaction of root-retained overdentures: A systematic review of randomised controlled clinical trials

OBJECTIVE

To evaluate clinical parameters that affect the performance of root-supported overdentures (ROD) and to identify the possible factors that may affect it.

BACKGROUND

ROD still serve as an alternative and successful treatment plan nowadays for partially edentulous patients. Nonetheless, there is not yet conclusive evidence about their clinical evaluation.

MATERIALS AND METHODS

A search strategy was developed following a PIO (Population, Intervention, Outcome) framework including an electronic search in the following databases: PubMed, Cochrane Library and Scopus. The systematic search included only randomised controlled clinical trials (RCTs), published until January 2023 in English language and was performed by two independent reviewers. Quality assessment of the included studies was conducted according to the Cochrane Risk of Bias tool.

RESULTS

The final selection of studies included 11 RCTs. Clinically relevant variables derived from this search were: Complications, with caries being the most frequently reported, periodontal aspects and bone changes around abutment teeth. Additionally, methods and clinical suggestions for the maintenance of these restorations and patient-related outcomes were assessed. According to the risk of bias assessment, nine studies were considered of high risk, whereas only 2 of low risk. A meta-analysis was not feasible.

CONCLUSION

Within the limitations of this systematic review, ROD remain a viable treatment plan, offering better denture stability and bone preservation around abutment teeth and high patient satisfaction. Thorough oral hygiene and regular follow-ups are of utmost importance. Further well-designed RCTs are necessary for firmer conclusions.

Clinical Investigation of the Inhibitory Effects of Tooth-Coating Materials on Initial Active Root Caries: A Pilot Randomized Controlled Trial

Background and Objectives: Caredyne ZIF-C is a novel, capsule-mixed zinc-containing prototype glass ionomer cement (GIC). Zinc ions are reported to inhibit root dentin demineralization, dentin collagen degradation, bacterial growth, acid production, and in vitro bacterial biofilm formation. However, the effectiveness of GICs against initial root caries lesions is unclear. Therefore, this study aimed to evaluate the efficacy of GICs, especially the new zinc-containing Caredyne ZIF-C GIC, as tooth-coating materials in patients with initial active root caries. Materials and Methods: A total of 58 lesions in 47 older adults (age > 65 years) were randomly allocated to one of the following three groups: Caredyne ZIF-C, Fuji VII (a conventional GIC), and sodium fluoride (NaF). All the lesions were treated with the assigned materials without removing the infected dentin, and the rates of dental plaque attachment and coating material fall-out were evaluated after 3, 6, and 12 months. The failure rate was defined as the number of teeth that needed restoration due to caries progression. Results: The plaque attachment rates tended to be lower in the material-coated root surfaces than in the healthy exposed root surfaces after 3, 6, and 12 months, although the differences among the three groups were not significant. Moreover, the coating material fall-out rate tended to be lower in the Caredyne ZIF-C group than in the Fuji VII group. There was no significant difference in the failure rate among the three groups at the 12 months mark. Conclusions: Though this pilot study offers a new direction for suppressing the progression of initial active root caries by controlling plaque attachment using GICs including Caredyne ZIF-C, clinical studies with a larger sample size are needed.

Prevalence, and Risk Indicators of Coronal and Root Caries in Mexican Older Adults in Nursing Homes

Background

Several factors are associated with coronal and root caries in older persons. The purpose of this study was to determine the experience, prevalence, and risk indicators (socioeconomic, sociodemographic, and dental variables) of coronal and root caries in older persons residing in nursing homes in Mexico.

Methods

A cross-sectional study was carried out in 227 dentate participants with natural teeth. Convenience sample, where all dentate residents were invited to participate. The dependent variables were coronal caries and root caries, which were determined through an oral clinical examination. The independent variables were sociodemographic factors, location, type of center, surfaces free of dental biofilm and calculus, surfaces with recession, retainers in contact with surfaces with recession, xerostomia, smoking, and the previous use of dental services. The binary logistic regression model was used in the analysis.

Results

The mean age of the participants in this study was 77.7±8.8 years, and 69.2% were women. Moreover, 71.8% live in long-term care facilities, and 48.0% live in Mexico City. The prevalence of coronal and root caries was found to be 67.8% and 50.7%, respectively. Being male and living in Mexico City were risk indicators for coronal caries, and with a 1% increase in surfaces with no biofilm, the risk decreased by 2%. Being widowed, having government or no social security, denture retainers, and coronal caries were risk indicators for root caries, while the utilization of dental services indicated lower risk.

Conclusion

Several variables that differ in nature were found to be risk indicators for coronal and root caries. Coronal caries increases the risk of root caries. Prevention should be aimed at identifying persons at higher risk, and dental care should be improved for persons living in long-term care institutions.

Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex vivo studies

Introduction and aim

The presence of host collagenases in the degradation of the protein matrix at later stages of carious dentin lesions development, as well as the potential involvement of bacterial collagenases, have been suggested but lack conclusive evidence. This study aims to conduct a systematic review to comprehensively assess the profile of host and bacterial-derived collagenolytic proteases in both root and coronal dentin carious lesions.

Methods

The search was performed in eight databases and the grey literature. Studies evaluating ex vivo dentin, extracted teeth, or biofilms from natural caries lesions were included. The methodological quality of studies was assessed using the Joanna Briggs Institute tool. Synthesis of the results and the certainty of evidence were performed following the Synthesis without Meta-analysis (SWiM) checklist and GRADE approach for narrative synthesis, respectively.

Results

From 935 recovered articles, 18 were included. Although the evidence was very uncertain, it was possible to suggest that 1) MMP-2, MMP-9, MMP-13, and CT-B may be increased in carious dentin when compared to sound dentin; 2) there is no difference in MMP-2 presence, while MMP-13 may be increased in root when compared to coronal carious dentin; 3) there is no difference of MMP-2 and MMP-9 expression/activity before and after cavity sealing; 4) MMP-8 may be increased in the dentin before cavity sealing compared to dentin after cavity sealing; 5) there is no difference of MMP-20 in irradiated vs. non-irradiated carious dentin. MMP-20 probably reduces in carious outer dentin when compared to carious inner dentin (moderate certainty). Genes encoding bacterial collagenolytic proteases and protein-degrading bacteria were detected in coronal and root carious lesions.

Conclusion

Trends in the direction of the effect were observed for some collagenolytic proteases in carious dentin, which may represent a potential target for the development of new treatments. (Protocol register-PROSPERO: CRD42020213141).

Viability of bacteria associated with root caries after Nd:YAG laser application in combination with various antimicrobial agents: An in vitro study

BACKGROUND

The neodymium-doped yttrium aluminum garnet (Nd:YAG) laser has various therapeutic applications in dentistry, including the treatment of dentin hypersensitivity and the bacterial reduction therapy in periodontology. The addition of antimicrobial agents may enhance the impact of the laser on bacterial viability.

OBJECTIVES

This in vitro study aimed to assess the effect of Nd:YAG laser application in combination with various chemical antimicrobial agents, including hydrogen peroxide (H2O2), sodium hypochlorite (NaOCl), chlorhexidine (CHX), and sodium fluoride (NaF), on the viability of bacteria implicated in the etiology of root caries.

MATERIAL AND METHODS

Three oral bacterial species were examined: Streptococcus mutans (S. mutans); Streptococcus sanguinis (S. sanguinis); and Enterococcus faecalis (E. faecalis). The bacteria were grown in broth at 37°C, and then treated with the chemical agents and/or irradiated with an Nd:YAG laser for 30 s. Each treatment modality was repeated 3 times: group 1 - no treatment; group 2 - 0.5% H2O2; group 3 - 0.5% NaOCl; group 4 - 0.12% CHX; group 5 - 2% NaF; group 6 - Nd:YAG laser irradiation; group 7 - laser and 0.5% H2O2; group 8 - laser and 0.5% NaOCl; group 9 - laser and 0.12% CHX; and group 10 - laser and 2% NaF. The viability of the bacteria was determined by plating them, counting viable colonies, converting the data into colony-forming units (CFUs)/mL, and transforming them into the log form. Statistical analysis was performed using the two-tailed paired t test.

RESULTS

Irradiation with an Nd:YAG laser alone did not show a statistically significant effect against any of the bacterial species. The only effective antimicrobial used alone was CHX for S. mutans. Chlorhexidine with Nd:YAG resulted in a greater reduction in S. mutans and E. faecalis than either treatment alone. Meanwhile, H2O2 with Nd:YAG also showed an enhanced S. mutans reduction. Treatment with 0.5% NaOCl in conjunction with Nd:YAG brought the most significant reduction in viability for all bacteria in comparison with other treatment modalities.

CONCLUSIONS

The Nd:YAG laser combined with 0.5% NaOCl resulted in the most substantial reduction in bacterial survival as compared to the antimicrobials or the Nd:YAG laser used alone.

Effect of a single application of silver diamine fluoride on root caries after 12 months in institutionalised older adults-A randomised clinical trial

OBJECTIVE

Silver diamine fluoride (SDF) has been shown to be highly effective against caries, in particular for arresting root surface caries and for dentine caries in primary teeth. SDF may complement fluoride varnish routines for treatment of root caries in nursing home residents. The aim of this randomised, single-blinded, placebo-controlled trial was to evaluate the additive effect of a single annual application of SDF for prevention and treatment of incipient root caries in older adult nursing home residents.

METHOD

Four hundred older adult nursing home residents (≥70 years old) with at least one exposed root surface (on teeth 15, 14, 13, 23, 24, or 25) were identified during routine dental examination visits in the domiciliary dental care setting. Eligible patients, who were able to understand the implication of consenting to the study, were invited to participate. Their cleaned root surfaces were randomly allocated to treatment with SDF (Advantage Arrest Silver Diamine Fluoride 38%, Advantage Arrest, LLC, Redmond, OR 97756, USA, Lot 16 152) or with placebo (tap water), each for 1 minute.

RESULTS

Of the 400 eligible individuals, 42 declined to participate and two forms were destroyed. The remaining 356 participants (89.0%; mean age 87.7 years) were randomly allocated, with 174 going to the SDF group and 182 to the placebo group. At 1 year, 273 participants (76.7%) were available for assessment: 135 in the SDF group and 138 in the placebo group. By that time, 109 individuals (39.9%) demonstrated root caries progression or regression. Among those 118 (16.7%) of the 708 included root surfaces had developed caries There were no statistically significant differences in the primary outcome related to treatment with SDF or placebo, at either patient or root surface level.

CONCLUSION

Based on the finding of this clinical trial, it is concluded that a single SDF application to complement a risk-based preventive programme including fluoride varnish applications did not have a statistically significant additional preventive effect on root caries development in a group of older adult nursing home residents with limited caries activity and cognitive capacity to cooperate in oral care activities.

The Association Between Seeking Urgent Dental Care and the Prevalence of Root Caries Among Patients in the United States, National Health And Nutrition Examination Survey 2017-2020: A Cross-Sectional Study

OBJECTIVE

This cross-sectional study aimed to investigate the association between seeking urgent dental care and the prevalence of root caries among patients in the United States, utilizing data from the Nutritional Health and Examination Survey (NHANES) conducted between 2017 and 2020. Our hypothesis is that patients who are seeking urgent dental care due to pain will have a high prevalence of root caries.

METHODS

The study utilized a cross-sectional design, analyzing data from NHANES 2017-March 2020 pre-pandemic data, a nationally representative survey. The sub-sample consisted of 6,186 participants aged 20 years and older who underwent oral health assessments, including the examination of root caries. Information on seeking urgent dental care was obtained through self-reported data. Statistical analyses, using SAS 9.4 (SAS Institute Inc., Cary, NC), were performed to assess the association between urgent care seeking and root caries prevalence while controlling the potential confounding variables. Descriptive statistics and multivariable logistic regression were used.  Results: The study included a total of 6,186 participants. The mean age (SD) of the participants was 49.7 (17.2). Some 52% were females and 48% were males. Some 14% (849) of the samples had root caries and 28% (1739) of the participants were seeking urgent dental care due to pain. Findings indicated a significant association between seeking urgent dental care and the prevalence of root caries (odds ratio, OR = 2.72, 95% confidence interval, CI = 2.32-3.18). Individuals who reported seeking urgent care had a higher prevalence of root caries (26% vs. 9%) compared to those who did not seek urgent care. Socioeconomic factors such as poverty and education, and other factors such as age, gender, race, marital status, and alcohol intake were identified as potential confounders.

CONCLUSION

This study provides evidence of the association between seeking urgent dental care and the prevalence of root caries among patients in the United States. The findings underscore the importance of promoting regular dental visits, preventive measures, and early interventions to mitigate the risk of root caries among individuals seeking urgent dental care. Addressing socio-economic barriers, improving access to dental services, and enhancing oral health education are crucial steps toward reducing the burden of root caries in this population. Further, longitudinal studies are recommended to establish the temporal relationship between urgent care seeking and root caries development.

Oral Health Factors Related to Rapid Oral Health Deterioration among Older Adults: A Narrative Review

Older adults who face systemic health issues and lack adequate social support are at risk for oral health deterioration. How rapidly such changes take place depends on the severity of their medical condition and their ability to access oral health services in a timely manner. The management of dental caries and periodontal disease in this cohort is made complex by the interaction of local and host factors such as the presence of dry mouth, involvement of root surfaces, and altered wound healing. in addition to enhanced maintenance needs to avoid recurrence or progression. Tooth replacement can be beneficial in restoring oral function, allowing patients to enjoy a healthy and nutritious diet but requires careful consideration to avoid further damage to remaining dental units. Establishing a dental home for the older adult can facilitate routine surveillance, disease prevention, and patient/caregiver education to achieve oral health goals commensurate with overall health. This narrative review details oral health factors that are related to rapid oral health deterioration among older adults.

Comparison of natural and artificial root caries lesions using microcomputed tomography and microhardness test

BACKGROUND

This study compared natural root caries lesions with artificial root caries lesions prepared with one of the two demineralising solutions.

METHODS

Twelve natural root caries lesions on upper incisors and 24 artificial root lesions were prepared on sound root surfaces using 50 mM acetic acid, 1.5 mM CaCl₂ , 0.9 mM KH₂ PO₄ at pH 5.0 or 80 mL/L Noverite K-702 polyacrylate solution, 500 mg/L hydroxyapatite, 0.1 mol/L lactic acid at pH 4.8 (n = 12/group) for 96 hours. Lesions were scanned using micro-CT. Inciso-gingival oriented images were analysed and mineral density calculated at 7.5 μm increments from the surface to 225-μm deep. Sectioned lesions were analysed by Knoop microhardness up to 250 μm from the lesion surface. Data were analysed by the Dunn's test with Bonferroni correction.

RESULTS

Natural and artificial lesion mean mineral densities were not statistically different (P > 0.05). Mineral density from the surface to 75 μm was greater in natural lesions and from 150 to 225 μm was greater in artificial lesions (P < 0.05). Microhardness values were statistically higher in artificial lesions (P < 0.05); no difference was found among artificial lesions produced by the two solutions (P > 0.05). Mineral density and microhardness of natural and artificial root caries are different from each other. A greater mineralized surface layer existed on natural lesions.

The Effect of Domiciliary Professional Oral Care on Root Caries Progression in Care-Dependent Older Adults: A Systematic Review

With care dependency, untreated root caries lesions (RCLs) and irregular dental visits are common. RCLs, if left untreated, could lead to pain, tooth loss, difficulties eating, and impact on general health. Therefore, there is a need for prevention and effective treatment for RCLs, and especially in those with care dependency. The aim of this systematic review was to investigate the effect of domiciliary professional oral care on root caries development and progression, in comparison with self-performed or nurse-assisted oral care. A literature search was conducted in four databases in November 2022. Two authors independently screened the literature throughout the review process. Five of the identified studies were found to be relevant. Four of these were assessed as having moderate risk of bias and were included in the review, while one study had high risk of bias and was excluded from further analyses. Due to heterogenicity of the included studies (and of the interventions and outcomes), no meta-analysis or synthesis without meta-analysis (SWiM) was performed. The participation of dental personnel performing mechanical plaque removal and fluoride, or chlorhexidine application seems beneficial for care-dependent older adults with risk of RCLs development and progression. However, future studies are needed.

Prevention of Root Caries Using Oxalic Acid

Certain dentin hypersensitivity treatment materials include oxalic acid to coat dentin surfaces with minerals, while certain organic acids possess a remineralization effect. Herein, an organic acid that inhibits the demineralization and coating of root surfaces was evaluated. Specimens were produced using five non-carious extracted bovines. Four different acids were used: oxalic acid (OA), malonic acid (MA), polyacrylic acid (PA), and succinic acid (SA). Each acid was applied to the root surface and washed using distilled water or a remineralization solution, and the surface was observed using scanning electron microscopy (SEM). All the surfaces of each specimen, barring the polished surface, were covered with wax and immersed in an automatic pH cycling system for two weeks. Dentin demineralization was analyzed using transverse microradiography (TMR) before and after pH cycling. SEM analysis demonstrated that the three acid groups demineralized the dentin surface, whereas the OA group generated crystals covering the dentin surface, even in a distilled water environment. TMR analysis revealed that the OA groups showed significantly lower integrated mineral loss compared with the other groups, even in the distilled water environment. The results suggest that OA generates insoluble calcium oxalate crystals on the dentin and suppresses demineralization even under low saliva conditions.

Effects of Acidic Challenge on Demineralized Root Surface Treated with Silver Diamine Fluoride and Potassium Iodide

BACKGROUND

The aim of the study was to assess the protective effect of applying potassium iodide (KI) over silver diamine fluoride (SDF) on demineralized root dentin in the case of a sustained acidogenic attack.

METHODS

Forty caries-free third molars were used in the study. A diamond disc was used to separate the roots and the tooth crowns from the roots. Each root fragment was randomly distributed in one of the four study groups: C-samples were not demineralized; DD-demineralized samples; RS1-demineralized samples covered with SDF+KI (RS-Riva Star product, SDI limited, Bayswater, Australia); RS2-demineralized samples covered with SDF+KI and submersed to another acidic challenge for 3 days. SEM and EDX were used for the morphological and elemental analysis. Vickers hardness assessment was performed using a tribometer CETR UMT-2 (Bruker Corporation, Berlin, Germany). One-way ANOVA and post hoc Bonferroni tests were used for the statistical analysis with a significance level of p < 0.05.

RESULTS

Morphological and elemental changes were observed on the surface of the study samples. Significant differences were observed between the recorded hardness values of groups C and DD (p = 0.005), C and RS2 (p = 0.002), DD and RS1 (p = 0.011); RS1 and RS2 (p = 0.004).

CONCLUSIONS

The application of SDF and KI (Riva Star product) on root dentin caries resulted in the formation of a heterogeneous outer layer that sealed the dentin and increased the microhardness of the treated surface. In the conditions of the present study, this layer did not provide enough protection for root dentin exposed to continuous attacks.

Active Surveillance of Root Caries in Vivo with CP-OCT

The active surveillance of root caries lesions to monitor potential remineralization or decay progression is challenging for the clinician, due to unreliable diagnostic information. The conventional visual and tactile methods for assessing the lesion activity are not reliable, and the clinician is often unable to determine if the lesion is progressing or has been arrested. An important marker of an arrested lesion is a highly mineralized transparent surface zone (TSL) that forms when the mineral is deposited in the outer layer of the lesion. The purpose of this study was to determine if cross-polarization optical coherence tomography (CP-OCT) could be used to detect changes in the lesion severity and activity during active monitoring. In total, 18 subjects with 22 suspected active root caries lesions were evaluated using CP-OCT at the baseline, 3 months, and 6 months. All subjects were instructed to use a high fluoride dentifrice at the baseline. The results showed that CP-OCT was able to discriminate the active from the arrested lesions by identifying the presence of a TSL on arrested lesions. The results also indicated that the mean TSL thickness increased significantly (p < 0.05) for the nine lesion areas. In addition, CP-OCT was able to show the progression of demineralization, erosion, and changes in gingival contours in scanned areas. CP-OCT was valuable for monitoring the activity and severity of root caries lesions in vivo. CP-OCT can be used to assess the activity of root caries lesions at a single time point by detecting the presence of a TSL at the lesion surface indicative of the lesion arrest.

Development of Root Caries Prevention by Nano-Hydroxyapatite Coating and Improvement of Dentin Acid Resistance

There is no established method for optimizing the use of dentin to prevent root caries, which are increasing in the elderly population. This study aimed to develop a new approach for root caries prevention by focusing on bioapatite (BioHap), a new biomaterial, combined with fluoride. Bovine dentin was used as a sample, and an acid challenge was performed in three groups: no fluoride (control group), acidulated phosphate fluoride treatment (APF group), and BioHap + APF treatment (BioHap group). After applying the new compound, the acid resistance of dentin was compared with that of APF alone. The BioHap group had fewer defects and an increased surface hardness than the APF group. The BioHap group had the smallest lesion depth and least mineral loss among all groups. Using a scanning electron microscope in the BioHap group showed the closure of dentinal tubules and a coating on the surface. The BioHap group maintained a coating and had higher acid resistance than the APF group. The coating prevents acid penetration, and the small particle size of BioHap and its excellent reactivity with fluoride are thought to have contributed to the improvement of acid resistance in dentin. Topical fluoride application using BioHap protects against root caries.

Inhibition of Demineralization of Dentin by Fluoride-Containing Hydrogel Desensitizers: An In Vitro Study

Several desensitizers routinely used clinically for dentin hypersensitivity are expected to inhibit demineralization. This study aimed to evaluate the effectiveness of sealing materials in inhibiting demineralization and increasing fluorine (F) uptake by acid-treated root surfaces. Five noncarious extracted human teeth were used to produce specimens. Three different fluoride-containing materials, namely "MS Coat F" (MS), "MS Coat Hys Block Gel" (HS), and CTX2 Varnish (FV), were used herein. Each material was applied to the demineralized root surface. Single sections were obtained from each specimen. All surfaces of each specimen, except the polished surface, were covered with wax and immersed in an automatic pH cycling system for 2 weeks. Fluorine and calcium distributions in the carious lesions of each specimen were evaluated using proton-induced gamma emission (PIGE) and X-ray (PIXE) techniques, respectively. Dentin demineralization was analyzed using transverse microradiography (TMR) before and after pH cycling. µPIXE/PIGE analysis demonstrated that all sample groups showed increased fluoride uptake on the root surface. TMR analysis revealed that both HS and FV showed significantly lower integrated mineral loss values than the control group. All three samples demonstrated a tendency towards increased fluoride uptake from fluoride-containing hypersensitivity desensitizers and a demineralization inhibition effect on root dentin.

A Co-Association of Streptococcus mutans and Veillonella parvula/dispar in Root Caries Patients and In Vitro Biofilms

Root caries in geriatric patients is a growing problem as more people are maintaining their natural teeth into advanced age. We determined the levels of various bacterial species previously implicated in root caries disease or health using quantitative real-time PCR in a pilot study of 7 patients with 1 to 4 root caries lesions per person. Levels of 12 different species on diseased roots compared to healthy (contralateral control) roots were measured. Four species were found at significantly higher levels on diseased roots (Streptococcus mutans, Veillonella parvula/dispar, Actinomyces naeslundii/viscosus, and Capnocytophaga granulosa) compared across all plaque samples. The level of colonization by these species varied dramatically (up to 1,000-fold) between patients, indicating different patients have different bacteria contributing to root caries disease. Neither of the two species previously reported to correlate with healthy roots (C. granulosa and Delftia acidovorans) showed statistically significant protective roles in our population, although D. acidovorans showed a trend toward higher levels on healthy teeth (P = 0.08). There was a significant positive correlation between higher levels of S. mutans and V. parvula/dispar on the same diseased teeth. In vitro mixed biofilm studies demonstrated that co-culturing S. mutans and V. parvula leads to a 50 to 150% increase in sucrose-dependent biofilm mass compared to S. mutans alone, depending on the growth conditions, while V. parvula alone did not form in vitro biofilms. The presence of V. parvula also decreased the acidification of S. mutans biofilms when grown in artificial saliva and enhanced the health of mixed biofilms.

Demonstration of an optical dentin hardness measuring device using bovine dentin with different demineralization times

SIGNIFICANCE

The increase in root caries is a serious problem as society ages. Root caries is diagnosed by inspection and palpation, which are qualitative. A method to objectively and quantitatively evaluate the progress of root caries in a clinical setting is strongly desired. The root caries could be diagnosed by measuring hardness because dentin becomes softer as the caries progresses. Vickers hardness has been customarily used as an indicator of tooth hardness. However, this method cannot be used to in vivo teeth because the teeth must be dried prior to measurement to make the indentation. A hardness meter using an indenter with light for tooth monitoring (HAMILTOM) is proposed as an optical device. HAMILTOM could measure hardness of teeth in wet condition as a dark area while applying a load to dentins without drying. Therefore, HAMILTOM may realize hardness measurements of in vivo teeth in a clinical setting quantitatively.

AIM

The aim of our study is to demonstrate the optical dentin hardness measuring device HAMILTOM using bovine dentin with different demineralization times and to evaluate the correlation between the dark areas measured by HAMILTOM and the Vickers hardness measured by the Vickers hardness tester.

APPROACH

The samples were 20 bovine dentins. They were demineralized by a lactic acid solution with different times and divided into groups 1 and 2 of 10 samples each. In both groups, the dark areas and Vickers hardness were measured for each sample. Group 1 was used to obtain a calibration curve to calculate Vickers hardness from the dark area. Group 2 was used to validate the calibration curve obtained from the dentin samples of group 1.

RESULTS

The areas appearing black without a total internal reflection of the indenter measured by HAMILTOM increased as the demineralization time increased. Additionally, the Vickers hardness of group 2 calculated by the dark areas of group 2 and the calibration curve obtained in group 1 and the Vickers hardness of group 2 measured by the Vickers hardness tester were strongly correlated with a determination coefficient of 0.99.

CONCLUSIONS

The results demonstrate that HAMILTOM may be a suitable alternative to the conventional method. Unlike the conventional method, which cannot be used for in vivo teeth, HAMILTOM holds potential to quantitatively evaluate the progress of caries in in vivo teeth.

Synchrotron radiation analysis of root dentin: the roles of fluoride and calcium ions in hydroxyapatite remineralization

Although the use of fluoride for root caries control is reported to be effective, the mechanism of maintaining hydroxyapatite is still unclear. This study elucidates the roles of fluoride in the recrystallization of hydroxyapatite, and the impact of calcium to maintain the abundance of hydroxyapatite on acid-challenged root dentin with a novel approach - using synchrotron radiation. Root dentin samples obtained from 40 extracted human premolars were subjected to pH challenge in combination with fluoride treatment. The effect of fluoride on hydroxyapatite regeneration on the root was investigated by using a range of fluoride concentrations (1000-5000 p.p.m.) and the EDTA-chelation technique in vitro. Synchrotron radiation X-ray micro-computed tomography and X-ray absorption spectroscopy were utilized to characterize the chemical composition of calcium species on the surface of prepared samples. The percentage of hydroxyapatite and the relative abundance of calcium species were subsequently compared between groups. The absence of calcium or fluoride prevented the complete remineralization of hydroxyapatite on the surface of early root caries. Different concentrations of fluoride exposure did not affect the relative abundance of hydroxyapatite. Sufficient potency of 1000 p.p.m. fluoride solution in promoting hydroxyapatite structural recrystallization on the root was demonstrated. Both calcium and fluoride ions are prerequisites in a caries-prone environment. Orchestration of F^- and Ca²⁺ is required for structural homeostasis of root dentin during acid attack. Sustainable levels of F^- and Ca²⁺ might thus be a strict requirement in the saliva of the population prone to root caries. Fluoride and calcium contribute to structural homeostasis of tooth root, highlighting that routine fluoride use in combination with calcium replenishment is recommended for maintaining dental health. This study also demonstrates that utilization of synchrotron radiation could provide a promising experimental platform for laboratory investigation especially in the dental material research field.

Periodontal Pathogens Inhabit Root Caries Lesions Extending beyond the Gingival Margin: A Next-Generation Sequencing Analysis

We performed a comprehensive microbiome analysis of root caries lesions using 22 teeth extracted from patients with severe periodontitis. The carious lesions were mechanically collected and cryo-pulverized following tooth extraction. Differences in the microbiome were compared between independent lesions at the supragingival site (SG) and lesions extending beyond the gingival margin (GCB). DNA was extracted and the microbiome was characterized on the basis of the V3-V4 hypervariable region of the 16S rRNA gene using paired-end sequencing on an Illumina MiSeq device. The microbiota in root caries lesions showed compositionally distinct microbiota depending on the location. The most abundant OTUs in the SG group were Streptococcus (26.0%), Actinomyces (10.6%), and Prevotella (7.6%). GCB presented Prevotella (11.1%) as the most abundant genus, followed by Fusobacterium (9.6%) and Actinomyces (8.7%). The SG group showed a lack of uniformity in microbiota compared with the GCB group. The bacterial profiles of GCB varied considerably among patients, including periodontal pathogens such as Porphyromonas, Selenomonas, Filifactor, Peptococcus, and Tannerella. Periodontal pathogens inhabit root caries lesions that extend beyond the gingival margin. This study provides a new perspective for elucidating the microbial etiology of root caries.

Perspective and practice of root caries management: a multicountry study - Part I

Background:

Every effort needs to be made to better understand the current state of practice and trends relating to root caries management which will be of benefit to dentists universally in the practice of dentistry.

Aim:

This article presents a multicountry questionnaire survey of the current state of practice in the management of root caries among dentists in nine different countries to get a wider range of opinions and perspectives.

Methodology:

A questionnaire related to root surface caries was distributed among practicing dentists in nine different countries, namely the United Kingdom, Libya, Jordan, Saudi Arabia, Egypt, Brazil, India, Malaysia, and Iraq. Questionnaire responses were analyzed, and the results were compared among groups.

Results:

The results showed statistically significant differences among dentists in most questionnaire aspects. Bleeding is the greatest obstacle facing dentists when restoring root surface lesions. Reported survival rates reflect uncertainty about the material and/or approach of choice in the management of root surface caries.

Conclusion:

This questionnaire survey revealed the current status of management of root surface caries in clinical practice in various countries. Substantial attention is required to bridge the knowledge gap and address the current void of uncertainty as relates to root caries management by providing a common ground for communication between dentists from all around the globe. In all, this work found a degree of consensus at the international level on what appears to work well among the dental practices surveyed and identified several issues with existing approaches that need to be addressed in future studies.

Root Caries Experience and its Association with Risk Indicators among Middle-Aged Adults

INTRODUCTION

With an increasing number of retained teeth, there is an enhanced susceptibility to periodontal problems with gingival recession, which led root surface exposure to the oral environment and develops the root caries later stages among adults.

AIM

Evaluate the root caries experience and its association with risk indicators among middle-aged South Indian adult dental patients using root caries index (RCI; Katz RV - 1979).

MATERIALS AND METHODS

The study was conducted among middle-aged (35 to 44 year) adults in the Outpatient Department of Private Dental Institute. Root caries experience was evaluated using the Katz RCI on a full mouth basis. Statistical analysis was done by using SPSS software.

RESULTS

The prevalence of root caries among study population was 8.9% with a mean RCI score of 1.04 ± 5.10. As age increased mean number of teeth with gingival recession (45.25 ± 27.09), decayed root surfaces (0.34 ± 1.11), filled root surfaces (0.39 ± 2.99), mean number of teeth missing (3.78 ± 6.42), and RCI (1.68 ± 6.93) also increased.

CONCLUSION

Age, gender and higher number of retained teeth were concluded as a significant risk indicators for root caries.

Assessment of the Potential Ability to Penetrate into the Hard Tissues of the Root of an Experimental Preparation with the Characteristics of a Dental Infiltratant, Enriched with an Antimicrobial Component-Preliminary Study

Infiltration is a method of penetration with a low viscosity resin that penetrates deep into demineralised tooth tissue and fills the intergranular spaces, hence reducing porosity. Carious lesions initially located at the enamel–cement junction are usually found in elderly patients. Those spots are predisposed to bacterial adhesion originating both from biofilm and from gingival pocket bacteria. The aim of this study was to evaluate the penetration of an experimental preparation, which has the characteristics of a dental infiltrant, enriched with an antibacterial component, into the decalcified root cement tissues of extracted human teeth in elderly patients. An experimental preparation with the characteristics of a dental infiltrant was prepared, applied, and polymerised on the surface of extracted, previously decalcified human teeth. The control sample was Icon (DMG, Hamburg, Germany). The ability of the preparations to penetrate deep into the root cement was evaluated using scanning electron and light microscopy. The study showed that an experimental preparation could potentially be used for treatment of early carious lesions within the tooth root in elderly patients, among others, as it penetrates deep into demineralised tissues. More research is needed.

Global Oral Health Policies and Guidelines: Using Silver Diamine Fluoride for Caries Control

Silver diamine fluoride (SDF) was developed in Japan in the 1960s. It is a clear solution containing silver and fluoride ions. Because of its anti-bacterial and remineralizing effect, silver diamine fluoride has been used in managing dental caries for decades worldwide. This paper aims to summarize and discuss the global policies, guidelines, and relevant information on utilizing SDF for caries management. SDF can be used for treating dental caries in most countries. However, it is not permitted to be used in mainland China. Several manufacturers, mainly in Australia, Brazil, India, Japan, and the United States, produce SDF at different concentrations that are commercially available around the world. The prices differ between contents and brands. Different government organizations and dental associations have developed guidelines for clinical use of SDF. Dental professionals can refer to the specific guidelines in their own countries or territories. Training for using SDF is part of undergraduate and/or postgraduate curriculums in almost all countries. However, real utilization of SDF of dentists, especially in the private sector, remains unclear in most places because little research has been conducted. There are at least two ongoing regional-wide large-scale oral health programs, using SDF as one of the components to manage dental caries in young children (one in Hong Kong and one in Mongolia). Because SDF treatment does not require caries removal, and it is simple, non-invasive, and inexpensive, SDF is a valuable strategy for caries management in young children, elderly people, and patients with special needs. In addition, to reduce the risk of bacteria or virus transmission in dental settings, using SDF as a non-aerosol producing procedure should be emphasized under the COVID-19 outbreak.

Using Proanthocyanidin as a Root Dentin Conditioner for GIC Restorations

Glass ionomer cements (GICs) are considered the material of choice for restoration of root carious lesions (RCLs). When bonding to demineralized dentin, the collapse of dentinal collagen during restorative treatment may pose challenges. Considering its acidic nature and collagen biomodification effects, proanthocyanidin (PAC) could be potentially used as a dentin conditioner to remove the smear layer while simultaneously acting to biomodify the dentinal collagen involved in the bonding interface. In this study, 6.5% w/v PAC was used as a conditioner for sound (SD) and laboratory demineralized (DD) root dentin before bonding to resin-modified GIC (FII), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-modified GIC (FVII), or a high-viscosity GIC (FIX). Root dentin conditioned with deionized distilled water (DDW) or polyacrylic acid (PAA) served as controls. Results indicated FII showed higher shear bond strength (SBS) on SD than the other 2 GICs, especially in PAA-conditioned samples; FIX showed significantly higher SBS than FII and FVII on PAA- or PAC-conditioned DD. In each category of GIC, PAA and PAC did not have a significant influence on SBS in most cases compared to DDW except for a significant decrease in PAC-conditioned SD bonded to FII and a significant increase in PAA-conditioned DD bonded to FIX. The bonding interface between GIC and SD was generally more resistant to the acid-base challenge than DD. Although the alterations in failure modes indicated a compromised interfacial interaction between GICs and PAC-treated root dentin, biomodification effects of PAC on dentin were observed from Raman microspectroscopy analysis in terms of the changes in mineral-to-matrix ratio and hydroxyproline-to-proline ratio of dentin adjacent to the bonding interface, especially of DD. Results from this study also indicated the possibility of using in situ characterization such as Raman microspectroscopy as a complementary approach to SBS test to investigate the integrity of the bonding interface.

Root Caries Preventive Effect of Varnishes Containing Fluoride or Fluoride + Chlorhexidine/Cetylpyridinium Chloride In Vitro

Caries preventive varnishes containing only fluoride might differ from those containing a combination of fluoride and antimicrobial components in terms of mineralization properties and their impact on the cariogenic biofilm. We compared a fluoride and a fluoride + chlorhexidine (CHX)/cetylpyridinium chloride (CPC) varnish on root caries formation in vitro. One hundred bovine root dentin samples were allocated to five groups (n = 20/group): (1) 7700 ppm fluoride varnish (Fluorprotector S (F)), (2) experimental placebo varnish for F (F-P), (3) 1400 ppm fluoride + 0.3% CHX/0.5% CPC varnish (Cervitec F (CF)), (4) experimental placebo varnish for CF (CF-P), (5) untreated control. Cariogenic challenge was provided using a multi-station, continuous-culture 3-species (Streptococcus mutans (SM), Lactobacillus rhamnosus (LR), Actinomyces naeslundii (AN)) biofilm model for 10 days. Mineral loss (ΔZ) was evaluated using transversal microradiography and bacterial counts in the biofilm assessed as colony-forming units. Fluorescence in situ hybridization (FISH) and confocal microscopy were performed to assess the three-dimensional biofilm architecture. Mean ± SD (vol% × μm) ΔZ was significantly lower for F (9133 ± 758) and CF (9835 ± 1677) compared to control (11362 ± 919) (p < 0.05), without significant differences between F and CF. SM counts were significantly lower and LR counts significantly higher in F- and CF-biofilms compared to control. AN counts were significantly higher in the F-biofilms than in all other groups. According to FISH, SM and LR invaded dentinal tubules only in the control-group. In the CF-group, the basal biofilm layer did not contain SM and AN. Both F and CF varnishes had similar caries-preventive effects and a considerable impact on biofilm structure and composition.

Perspective and practice of root caries management: A multicountry study - Part II: A deeper dive into risk factors

BACKGROUND

The potential of an improved understanding to prevent and treat a complex oral condition such as root caries is important, given its correlation with multiple factors and the uncertainty surrounding the approach/material of choice. Deeper insights into risk factors may improve the quality of treatment and reduce the formation of root surface caries.

AIM

The present work aims to gain knowledge about dentists' opinions and experiences on assessing the risk factor related to the development of root caries and to help identify any overlooked factors that may contribute to less efficacious clinical outcomes.

METHODOLOGY

A questionnaire related to root surface caries was distributed among practicing dentists in nine different countries, namely the United Kingdom, Libya, Jordan, Saudi Arabia, Egypt, Brazil, India, Malaysia, and Iraq. Questionnaire responses were analyzed, and the results were compared among the groups.

RESULTS

Dentists around the world ranked the oral hygiene status of patients as the most important factor in the development of root surface caries. Patients with poor oral hygiene, active periodontal disease, reduced salivary flow, and gingival recession are perceived to have a higher risk of developing new root surface caries. There is a greater focus on prevention in the UK and greater levels of untreated dental disease in other countries, especially those recovering from civil wars.

CONCLUSION

This work identified some overlooked factors that may have contributed to the less efficacious clinical outcomes reported in the literature. It is hoped that this deep dive into risk factors coupled with the findings presented in Part I of this study will be used as a basis for a more comprehensive investigation into the management of patients with root surface caries.

Tests to detect and inform the diagnosis of root caries

BACKGROUND

Root caries is a well-recognised disease, with increasing prevalence as populations age and retain more of their natural teeth into later life. Like coronal caries, root caries can be associated with pain, discomfort, tooth loss, and contribute significantly to poorer oral health-related quality of life in the elderly. Supplementing the visual-tactile examination could prove beneficial in improving the accuracy of early detection and diagnosis. The detection of root caries lesions at an early stage in the disease continuum can inform diagnosis and lead to targeted preventive therapies and lesion arrest.

OBJECTIVES

To assess the diagnostic test accuracy of index tests for the detection and diagnosis of root caries in adults, used alone or in combination with other tests.

SEARCH METHODS

Cochrane Oral Health's Information Specialist undertook a search of the following databases: MEDLINE Ovid (1946 to 31 December 2018); Embase Ovid (1980 to 31 December 2018); US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov, to 31 December 2018); and the World Health Organization International Clinical Trials Registry Platform (to 31 December 2018). We studied reference lists as well as published systematic review articles.

SELECTION CRITERIA

We included diagnostic accuracy study designs that compared one or more index tests (laser fluorescence, radiographs, visual examination, electronic caries monitor (ECM), transillumination), either independently or in combination, with a reference standard. This included prospective studies that evaluated the diagnostic accuracy of single index tests and studies that directly compared two or more index tests. In vitro and in vivo studies were eligible for inclusion but studies that artificially created carious lesions were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data independently and in duplicate using a standardised data extraction and quality assessment form based on the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) specific to the review context. Estimates of diagnostic test accuracy were expressed as sensitivity and specificity with 95% confidence intervals (CI) for each dataset. We planned to use hierarchical models for data synthesis and explore potential sources of heterogeneity through meta-regression.

MAIN RESULTS

Four cross-sectional diagnostic test accuracy studies providing eight datasets with data from 4997 root surfaces were analysed. Two in vitro studies evaluated secondary root caries lesions on extracted teeth and two in vivo studies evaluated primary root caries lesions within the oral cavity. Four studies evaluated laser fluorescence and reported estimates of sensitivity ranging from 0.50 to 0.81 and specificity ranging from 0.40 to 0.80. Two studies evaluated radiographs and reported estimates of sensitivity ranging from 0.40 to 0.63 and specificity ranging from 0.31 to 0.80. One study evaluated visual examination and reported sensitivity of 0.75 (95% CI 0.48 to 0.93) and specificity of 0.38 (95% CI 0.14 to 0.68). One study evaluated the accuracy of radiograph and visual examination in combination and reported sensitivity of 0.81 (95% CI 0.54 to 0.96) and specificity of 0.54 (95% CI 0.25 to 0.81). Given the small number of studies and important differences in the clinical and methodological characteristics of the studies we were unable to pool the results. Consequently, we were unable to formally evaluate the comparative accuracy of the different tests considered in this review. Using QUADAS-2 we judged all four studies to be at overall high risk of bias, but only two to have applicability concerns (patient selection domain). Reasons included bias in the selection process, use of post hoc (data driven) positivity thresholds, use of an imperfect reference standard, and use of extracted teeth. We downgraded the certainty of the evidence due to study limitations and serious imprecision of the results (downgraded two levels), and judged the certainty of the evidence to be very low.

AUTHORS' CONCLUSIONS

Visual-tactile examination is the mainstay of root caries detection and diagnosis; however, due to the paucity of the evidence base and the very low certainty of the evidence we were unable to determine the additional benefit of adjunctive diagnostic tests for the detection and diagnosis of root caries.

Remineralising effects of fluoride varnishes containing calcium phosphate on artificial root caries lesions with adjunctive application of proanthocyanidin

OBJECTIVES

To evaluate the remineralising effects of fluoride (F) varnishes containing bioavailable calcium-phosphate compound (Ca-P) based remineralisation systems and 5000 ppm F toothpaste (FTP) on root caries lesions (RCLs) and the potential effects of proanthocyanidin (PA) for the treatments of RCLs when used as an adjunct to F regimens.

METHODS

Demineralised root dentine and a pH-cycling model were used to mimic RCLs and the oral environment. Remineralising effects of MI Varnish^TM (MIV) containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and Clinpro™ White Varnish (CPWV) containing tri-calcium phosphate (TCP) along with FTP and PA were evaluated regarding the birefringence, elemental composition, mechanical properties and mineral density of remineralised dentine with Duraphat^TM as a comparison.

RESULTS

MIV, CPWV and Duraphat^TM promoted the incorporation of F into RCLs and increased mineral density but did not change microhardness of root dentine significantly. Surface microhardness increased significantly when MIV or CPWV was used with 5000 ppm FTP. Application of PA with F regimens significantly increased subsurface mineral density. When PA was applied with MIV or CPWV along with FTP, the highest ion uptake and relative mineral gain (%ΔZ) was achieved, and significant increase of microhardness was up to 30 μm depth. Generally, MIV was associated with a higher mineral content gain than CPWV.

SIGNIFICANCE

Treatment of carious root surfaces remains challenging due to the complex pathological processes and difficulty in restoring the highly organised structure of root dentine. Treatment strategies targeting both remineralisation and preservation of the dentinal organic matrix have the potential to improve the fluoride-mediated remineralisation approaches.

Inequalities in Untreated Root Caries and Affordability of Dental Services among Older American Adults

The growing geriatric population is facing numerous economic challenges and oral health changes. This study explores the relationship between affordability of dental care and untreated root caries among older American adults, and whether that relationship is independent of ethnicity and socioeconomic factors. Data from 1776 adults (65 years or older) who participated in the National Health and Nutrition Examination Survey (NHANES) were analyzed. The association between affordability of dental care and untreated root caries was assessed using logistic regression models. Findings indicated that untreated root caries occurred in 42.5% of those who could not afford dental care, and 14% of those who could afford dental care. Inability to afford dental care remained a statistically significant predictor of untreated root caries in the fully adjusted regression model (odds ratio 2.79, 95% confidence interval: 1.78, 4.39). Other statistically significant predictors were gender (male), infrequent dental visits, and current smoking. The study concludes that the inability to afford dental care was the strongest predictor of untreated root caries among older Americans. The findings highlight the problems with access to and use of much needed dental services by older adults. Policy reform should facilitate access to oral healthcare by providing an alternative coverage for dental care, or by alleviating the financial barrier imposed on older adults.

Contemporary Challenges and Management of Dental Caries in the Older Population

The prevalence of caries is set to increase in the coming years as a result of a growing ageing population and a concomitant reduction in levels of edentulousness. Evidence for management of caries in older adults is scarce compared to that for the child population, however, similar principles of risk assessment, prevention and minimal intervention should be applied by dental health professionals. Early identification of high-risk older adults facilitates the implementation of risk reduction strategies, such as topical fluoride regimes. When operative intervention cannot be avoided, Atraumatic Restorative Technique (ART) may allow for conservative cavity preparation and has the advantage of being suitable for the domiciliary setting.

Comparative Evaluation of Root Caries Remineralization Effect of Plain Milk, 5 ppm of Fluoridated Milk, and 5 ppm of Sodium Fluoride in Deionized Water Using Surface Microhardness Test: An In Vitro Study

Background:

There is an increase in longevity of teeth retained in elderly population, leading to increased risk of root caries. Therefore, new and affordable preventive strategies are in need to reduce this problem. Hence, the aim and objective of the study was to assess and compare the root caries remineralization effect of plain milk, 5ppm of fluoridated milk, and 5ppm of NaF in deionized water.

Materials and Methods:

The study was an in vitro experimental design. Sixty root samples were divided into five groups (sound root, demineralized root treated in deionized water, plain milk, 5-ppm fluoridated milk, and 5-ppm fluoridated deionized water) of 12 samples each after baseline surface microhardness analysis and standardization was carried out in the study. All groups except the sound root were subjected to demineralization procedure for 4 days at 37°C. The demineralized four groups were treated to test solutions and subjected to pH cycling for 14 days. This was followed with assessment of postintervention surface microhardness. Student’s paired t test was used for comparing surface within groups. One-way analysis of variance test and post hoc Tukey’s test were conducted for between groups’ comparison.

Results:

There was a significant difference between groups (P < 0.05). The results of post hoc showed that significant difference was found between the group sound root and demineralized treated with 5-ppm fluoridated milk and 5-ppm fluoridated deionized water with an effect size of 2.15 and 2.87, with CI (–26.8 to –8.1) and (–36 to –17.3), respectively. There was a significant difference in all the groups when compared within the group (P < 0.05).

Conclusion:

Plain milk, 5-ppm fluoridated milk, and 5-ppm fluoridated deionized water showed remineralizing potential against demineralized in vitro root caries samples. 5-ppm fluoridated deionized water and 5-ppm fluoridated milk have a better effect compared to plain milk.

Prevalence and severity of periodontal disease in a historical Austrian population

Objective

To assess the prevalence and severity of periodontitis based on different diagnostic methods in a historical Austrian population from the early middle ages.

Background

The description of the oral health status of archaeological material can provide interesting insights into prevalence, severity, and extent of oral diseases. Herein, the periodontal health status of the skeletal remains of medieval Avars (700‐800 AD), which were considered as one of the earliest Avarian settlements in Austria, was investigated.

Methods

The skeletal remains of 128 Avars were examined; age and gender were estimated by standard forensic methods and tooth loss and root caries were recorded. Periodontitis was assessed by (a) measurement of the alveolar bone levels (ABL) and (b) evaluation of the interdental septa.

Results

A mean ABL of 4.8 mm was determined, root caries tended to accumulate in teeth with a higher alveolar bone loss, and on average, 6.2 teeth were lost antemortem. Independent of the diagnostic method >90% of the subjects were judged as periodontally diseased, and age and tooth type were significant predictors. However, on the tooth level the presence of periodontitis varied considerably depending on the diagnostic method; that is, 7.6% versus 47.2% of the teeth were judged as healthy based on ABL or interdental septa, respectively.

Conclusion

The periodontal status of the skeletal remains of medieval Avars revealed a considerable high prevalence of periodontitis (ie, >90% of this population displayed periodontal tissue breakdown). However, the diagnostic method, disease definition, and data presentation should be considered when comparing results of archaeological material.

National Study of Adult Oral Health 2017-18: root caries

BACKGROUND

The prevalence of root caries in Australia is expected to increase due to an ageing population and increase in tooth retention. This report presents findings from the Australian National Study of Adult Oral Health 2017-18.

METHODS

A stratified random sample of 15 731 Australians aged ≥15 years participated in a telephone or online survey. Of those, 5022 dentate people underwent an oral assessment. Carious root surfaces were defined as ≥1 mm of affected dentine/cementum. Prevalence was defined as the percentage with ≥one natural tooth with untreated caries on root surfaces. Severity was measured as the mean number of root surfaces with caries.

RESULTS

Prevalence of untreated root caries in the Australian adult dentate population was 8.2% and increased with increasing age (range 2%-17.8%). Men (9.3%) compared to women (7.2%), people living in remote (18.0%) versus regional (9.3%) and major cities (7.6%), and those with the lowest household income (15.4%) compared to middle (7.6%) and highest tertile (3.2%) had untreated root caries. The average number of decayed or filled root surfaces in the Australian adult population was 1.1 (95% CI 0.9, 1.2).

CONCLUSIONS

Root caries was associated with older age, living outside a major city and lower income.

Prevalence and risk factors of root caries in the geriatric population in the rural sector

Introduction

Increasing age, long-term deleterious habits, and increased bone resorption leading to the gingival recession have become a significant reason for poor geriatric oral health among which root caries are the most prevalent ones among the Indian population.

Methodology

A cross-sectional study was conducted among the geriatric population above 60 years of age and those who gave voluntary consent for participating in the study were included in the study and were briefed about the questionnaire. The self-administered questionnaire was given and complete oral examination was done. Results were analyzed using the SPSS 22 version using descriptive analysis and Chi-square test.

Result

Percentage of deleterious habits amongst males was higher than that of females i.e. 56%. Thus, males were reported with root caries more than females. The percentage of married people suffering from root caries was 85%. The most prevalent occupation among the geriatric population was found to be the farmers with 37%. Religion with maximum percentage and frequency was found to be Hinduism with 84%. Educational statuses with 6^th to 12^th standards were reported with maximum root caries, i.e. 55%.

Conclusion

The study showed that criteria including income, gender, marital status, occupation, religion, and educational status were significant in assessing the prevalence of root caries. Whereas the risk factors such as habits, methods of cleaning, and brushing techniques influenced the root caries among the geriatric population.

SWIR, Thermal and CP-OCT imaging probes for the in vivo assessment of the activity of root caries lesions

New imaging technologies are needed for the clinical assessment of lesions on root surfaces. It is not sufficient to simply detect caries lesions; methods are needed to assess lesion depth, structural composition and activity to determine if chemical intervention has the potential to be effective and if remineralization has occurred. Lesions were monitored using CP-OCT during lesion dehydration to assess the lesion structure and any shrinkage. Thermal imaging at 6-10 μm wavelengths and short wavelength-IR imaging at 1450-1750-nm were used to monitor thermal emission during lesion dehydration to assess lesion activity. Imaging probes were custom fabricated for clinical use. We present the first clinical results of a small feasibility study employing CP-OCT, thermal and SWIR imaging to assess lesion activity in vivo on thirty test subjects with suspected root caries lesions.

The frequency of enamel and dentin caries lesions among elderly Norwegians

Aim: To describe the distribution of enamel-, dentin-, root- and secondary caries within an elderly population in Northern-Norway.Material and methods: A study population (n = 1 173) was divided into age groups: 65-69 (seniors), 70-74 (young elderly), 75-79 (elderly) and 80-94 (old elderly). Seven examiners registered presence, location and severity of caries lesions on x-rays and intra-oral photos. Severity of approximal, occlusal, secondary and root caries was graded (D_1-2: into enamel; D_3-5: into dentin, root caries)_, and decayed missing filled surfaces/teeth (DMFS/DMFT) were calculated. T-test, ANOVA and a Bonferroni correction were used.Results: The seniors had more primary caries (DS_1-5) compared to the oldest age groups, while the old elderly had significantly more secondary caries than the other groups (p < .05). Of those ≥65 years 13.8% were affected with root caries, 21% among the oldest. About 48% of the old elderly had one or more surfaces with untreated caries lesions into dentin, while for the other groups the number was 35% (p < 0.05).Conclusion: Individuals seem to maintain good oral health up to at least 80 years of age. Those older than 80 years have more root caries needing more intensified caries-controlling measures and a higher prevalence of untreated dentin lesions often in need of operative treatment.

The association between periodontal disease and root/coronal caries

OBJECTIVES

To examine whether there is an association between periodontal disease and each of root caries and coronal caries among adults (aged 35 and over), using a nationally representative sample of adults in England, Northern Ireland and Wales.

MATERIAL AND METHODS

In this cross-sectional study, data from the Adult Dental Health Survey 2009 were used. Adults aged 35 years or older who had periodontal and caries assessment were included. Two sets of negative binomial regression were conducted for each of coronal caries and root caries adjusting for periodontal diseases, dental visits, country, sex, age, education, job classification, oral hygiene and smoking.

RESULTS

Overall, 4738 were included in the analysis. Periodontal disease was significantly associated with each of coronal and root caries. In the fully adjusted model, those with PD/ LoA ≥ 4 mm had 1.03 rate ratio (RR) for coronal caries (95% CI: 1.01-1.05). In the model pertaining to root caries, the RR for those with periodontitis was 1.23 (95% CI: 1.16-1.30). Smoking, sex, age and oral hygiene were the variables that showed a consistent and significant association with coronal and root caries.

CONCLUSION

Individuals with periodontal diseases appeared to be at higher risk of coronal and root caries. While root exposure could be a plausible explanation for the relationship between periodontitis and root caries, the association with coronal caries could be attributed to the irritation of carious cavities, or common risk factors such as poor oral hygiene, or co-occurrence of different health risk behaviours related to both caries and periodontitis and socioeconomic conditions.

Application of machine learning for diagnostic prediction of root caries

OBJECTIVE

This study sought to utilise machine learning methods in artificial intelligence to select the most relevant variables in classifying the presence and absence of root caries and to evaluate the model performance.

BACKGROUND

Dental caries is one of the most prevalent oral health problems. Artificial intelligence can be used to develop models for identification of root caries risk and to gain valuable insights, but it has not been applied in dentistry. Accurately identifying root caries may guide treatment decisions, leading to better oral health outcomes.

METHODS

Data were obtained from the 2015-2016 National Health and Nutrition Examination Survey and were randomly divided into training and test sets. Several supervised machine learning methods were applied to construct a tool that was capable of classifying variables into the presence and absence of root caries. Accuracy, sensitivity, specificity and area under the receiver operating curve were computed.

RESULTS

Of the machine learning algorithms developed, support vector machine demonstrated the best performance with an accuracy of 97.1%, precision of 95.1%, sensitivity of 99.6% and specificity of 94.3% for identifying root caries. The area under the curve was 0.997. Age was the feature most strongly associated with root caries.

CONCLUSION

The machine learning algorithms developed in this study perform well and allow for clinical implementation and utilisation by dental and nondental professionals. Clinicians are encouraged to adopt the algorithms from this study for early intervention and treatment of root caries for the ageing population of the United States, and for attaining precision dental medicine.

Atraumatic vs conventional restorative treatment for root caries lesions in older patients: Meta- and trial sequential analysis

OBJECTIVES

We aimed to appraise the comparative clinical efficacy of atraumatic restorative treatment (ART) versus conventional restorative treatment (CT) using a meta-analysis, and assessed the robustness of evidence by trial sequential analysis (TSA).

BACKGROUND

Due to its simplified clinical approach, ART may be advantageous over CT for restoration of root caries lesions in institutionalised older patients.

METHODS

Three electronic databases (PubMed, Embase and Cochrane CENTRAL) were screened, and hand searches and cross-referencing performed to identify randomised controlled trials reporting on survival of ART vs CT for restoration of root caries in older patients. Trial selection, data extraction and risk of bias assessment were performed by two independent reviewers. ART and CT were compared using fixed- or random-effects pairwise meta-analysis for per-protocol (PP), intention-to-treat (ITT) and best-case scenarios. TSA was used to control for risk of random errors.

RESULTS

A total of 235 studies were identified, and three trials involving 130 patients (463 restorations) were included. Risk of bias was high or moderate in all but one trial. ART was associated with a significantly increased risk of failure (OR [95% CI] 2.06 [1.06/4.00]) in PP- but not in ITT analysis (1.36 [0.92/2.02]). Analyses for best-case scenarios found great uncertainty introduced by attrition. No firm evidence was reached according to TSA.

CONCLUSIONS

For restoration of root caries, there is insufficient data to clearly rule out whether differences between ART and CT exist. Limited available data indicate there might be an increased risk of failure for ART.

An appliance for monitoring the shrinkage of root caries with OCT

Demineralized root dentin and cementum are mostly collagen that shrinks significantly upon dehydration. Active root caries lesions manifest shrinkage upon dehydration, however during the remineralization of root caries lesions mineral is deposited on the outside of the lesion arresting the lesion and arrested lesions no longer manifest shrinkage upon dehydration. Optical coherence tomography is ideally suited for the measurement of that shrinkage for the assessment of lesion activity. In this study the shrinkage of natural root caries lesions on extracted teeth were measured using a CP-OCT system with a 3D printed appliance with an integrated air nozzle suitable for clinical use.

Image guided laser ablation of demineralization from root surfaces

It is challenging to identify demineralized areas of root lesions due to cervical erosion, calculus formation, and heavy staining of dentin. We have found that root caries can be imaged with extremely high contrast at short wavelength IR (SWIR) wavelengths beyond 1500-nm. Lasers are well suited for the selective removal of caries lesions from tooth surfaces. A CO₂ laser operating at a wavelength of 9.3-μm was combined with a thulium-doped fiber laser operating at 1880-nm for the selective removal of root caries lesions from extracted teeth. Serial SWIR reflectance images at 1880-nm were used to guide the CO₂ laser for image-guided laser ablation. Cross polarization optical coherence tomography (CP-OCT) was used to assess the initial depth of the lesions before removal and assess the volume of sound and demineralized tissue removed by the CO₂ laser. With this image-guided approach, we believe we can achieve highly selective lesion removal and minimal damage to surrounding sound tissues.

Cross-polarization reflectance imaging of root caries and dental calculus on extracted teeth at wavelengths from 400 to 2350 nm

The identification of root caries and calculus on tooth roots is of increasing importance with our aging population. Exposed root surfaces are often impacted by erosion, abrasion, calculus and staining which can make the identification and management of caries challenging. Identification of dental calculus on root surfaces and verification of its removal is also important for patient education and to decrease susceptibility to caries and periodontal disease. The objective of this study was to determine how the contrast of root caries lesions and dental calculus varies with wavelength in the visible to near-infrared. The contrast of suspected root caries lesions and dental calculus on 30 extracted teeth was measured using cross-polarization reflectance measurements at wavelengths from 400 to 2350 nm. Significantly higher (P < 0.05) lesion contrast was measured at wavelengths greater than 1460 nm. Stains interfered significantly at wavelengths less than 850 nm yielding non-diagnostic contrast for root caries lesions. We postulate that the high absorption of water at longer wavelengths reduced the light scattering from the surrounding and underlying normal dentin, thus increasing the lesion contrast. This study indicates that wavelengths beyond 1400 nm are advantageous for imaging calculus and caries lesions on root surfaces due to the high contrast and lack of interference from stain.

How Root Caries Differs between Middle-aged People and the Elderly: Findings from the 4th National Oral Health Survey of China

OBJECTIVE

To investigate the differences in distribution of root caries and related factors between middle-aged and elderly people in China.

METHODS

In this cross-sectional study, a multistage, cluster strategy was used to recruit 4,410 participants (2,197 males and 2,213 females) aged 35 to 44 years and 4,431 participants (2,222 males and 2,209 females) aged 65 to 74 years from all 31 provinces, autonomous regions and municipalities of the mainland of China. The survey was conducted according to the basic methods proposed by the World Health Organization (WHO). Sociodemographic information, oral health behaviour, attitude and knowledge, history of dental prophylaxis and general health condition were collected with a closed questionnaire.

RESULTS

A great increase in the occurrence of root caries in Chinese adults from 35 to 44-year-old to 65 to 74-year-olds, with the prevalence (DFR ≥ 1) from 25.4% to 61.9% and with the mean DFR score from 0.54 ± 1.34 to 2.63 ± 3.75. Filling rates were also very low, only 1.8% and 3.0%, respectively. Females and residents of rural areas were more likely to suffer from root caries. In both the middle-aged group and the elderly group, root caries related to gender, education level, sweet food/drinks consumption, oral health knowledge and status of root surface explosion. In 35 to 44 year olds, toothbrushing is a significant protection factor (OR = 0.88, 95%CI 0.81 ~ 0.96), while using toothpicks is a risk factor (OR = 1.06, 95%CI 1.02 ~ 1.10). In 65 to 74 year olds, not having dental had scaling in the past 12 months is a risk factor (OR = 1.66, 95%CI 1.09 ~ 2.53).

CONCLUSION

Root caries among middle-aged people and elderly people in China have different risk factors and need more attention in future research to develop proper prevention.

Unexpected sequel to silver fluoride followed by stannous fluoride treatment of root stumps supporting an overlay denture in an aged-care patient

An institutionalized high care dementia patient, who is unable to maintain his own oral health, presented with five lower anterior carious root stumps supporting a lower overlay denture. Due to limited cooperation, his root stumps were treated with only silver fluoride followed by stannous fluoride applied topically on a 4-monthly cycle. Almost one and a half years after his initial application, there were unexpected calculus formations on the root stumps accompanied by marked gingival inflammation and gingival hyperplasia. At this point prognosis was considered very poor. Because the patient's cooperation was so poor, no attempt was made to remove the calculus deposits. Following continued topical applications directly to the area, there was evidence of a marked and unexpected improvement in gingival health. Some 4 years and 4 months after the initial application, the root stumps demonstrated a hard glossy surface surrounded by healthy gingival tissue. There had been no change in the patient's oral care, minor changes to medications and there had been no operative or periodontal interventions.

Dental caries and periodontal diseases in the ageing population: call to action to protect and enhance oral health and well-being as an essential component of healthy ageing - Consensus report of group 4 of the joint EFP/ORCA workshop on the boundaries between caries and periodontal diseases

BACKGROUND

Over the last two decades, progress in prevention and treatment of caries and periodontal diseases has been translated to better oral health and improved tooth retention in the adult population. The ageing population and the increasing expectations of good oral health-related quality of life in older age pose formidable challenges to clinical care and healthcare systems.

AIMS

The objective of this workshop was to critically review scientific evidence and develop specific recommendations to: (i) prevent tooth loss and retain oral function through prevention and treatment of caries and periodontal diseases later in life and (ii) increase awareness of the health benefits of oral health as an essential component of healthy ageing.

METHODS

Discussions were initiated by three systematic reviews covering aspects of epidemiology of caries and periodontal diseases in elders, the impact of senescence on caries and periodontal diseases and the effectiveness of interventions. Recommendations were developed based on evidence from the systematic reviews and expert opinion.

RESULTS

Key messages included: (i) the ageing population, trends in risk factors and improved tooth retention point towards an expected increase in the total burden of disease posed by caries and periodontal diseases in the older population; (ii) specific surveillance is required to monitor changes in oral health in the older population; (iii) senescence impacts oral health including periodontitis and possibly caries susceptibility; (iv) evidence indicates that caries and periodontal diseases can be prevented and treated also in older adults; (v) oral health and functional tooth retention later in life provides benefits both in terms of oral and general quality of life and in terms of preventing physical decline and dependency by fostering a healthy diet; (vi) oral healthcare professionals and individuals should not base decisions impacting tooth retention on chronological age but on level of dependency, life expectancy, frailty, comfort and quality of life; and (vii) health policy should remove barriers to oral health care for vulnerable elders.

CONCLUSIONS

Consensus was reached on specific actionable priorities for public health officials, oral healthcare professionals, educators and workforce planners, caregivers and relatives as well as for the public and ageing patients. Some priorities have major implications for policymakers as health systems need to adapt to the challenge by systemwide changes to enable (promote) tooth retention later in life and management of deteriorating oral health in increasingly dependent elders.

Root surface caries among older Australians

OBJECTIVES

Root caries has increased as a clinical problem in recent decades. However, the use of multiple waves of longitudinal follow-up data in estimating root caries increment has not been previously attempted. The aims of this study were to quantify root caries increment from a longitudinal study of older adults with 4 oral examinations over 11 years and to examine behavioural factors associated with root caries.

METHODS

A secondary analysis was undertaken using data collected in 4 waves (baseline, 2-year, 5-year and 11-year) of the South Australian Dental Longitudinal Study which began in 1991/92. The study group consisted of a stratified random sample of people aged 60+ years at baseline. A total of 358 participants with complete oral examinations in all 4 waves were included. The examinations were performed by trained and calibrated dentists. Baseline behavioural risk factors (toothbrushing frequency, flossing frequency, dental visiting pattern, reason for dental visiting and tobacco smoking status) and time in years across the 4 waves were the main exposures. Baseline clinical oral conditions (gingival condition and gingival recession), demographic and socio-economic risk factors served as covariates. Root caries was measured as mean number of untreated root surfaces (root DS) and decayed/filled root surfaces (root DFS) at each wave of examinations. Multivariable multilevel growth model using linear regression analysis was used to get an estimate for root caries increment and associated oral health-related behaviours adjusting for all the covariates.

RESULTS

Findings from the multivariable models indicated that the annual increment of root DS and root DFS were 0.07 (SE = 0.01) and 0.11 (SE = 0.02) surfaces, respectively. Irregular brushing (E [SE] = 0.25 [0.12]), visiting the dentist only for problems (E [SE] = 0.30 [0.13]) and smoking (E [SE] = 0.33 [0.12]) were risk factors for the increase in root DS. Irregular flossing and more frequent dental visit were associated with the increase in root DFS.

CONCLUSIONS

Root caries increased slowly across time among relatively healthier Australian older adults. Irregular brushing, unfavourable dental visiting and tobacco smoking were risk factors for the increase in untreated root caries, while irregular flossing and more frequent dental visiting were associated with the increase in root DFS.

Remineralization potential of nano-hydroxyapatite on enamel and cementum surrounding margin of computer-aided design and computer-aided manufacturing ceramic restoration

Objective

This study investigates the effects of nano-hydroxyapatite (NHA) gel and Clinpro (CP) on remineralization potential of enamel and cementum at the cavosurface area of computer-aided design and computer-aided manufacturing ceramic restoration.

Materials and methods

Thirty extracted human mandibular third molars were sectioned at 1 mm above and below the cemento-enamel junction to remove the cemento-enamel junction portions and replaced them with zirconia ceramic disks by bonding them to the crown and root portions with resin cement. The enamel and cementum with an area of 4×4 mm² surrounding the ceramic disk was demineralized with carbopol. The demineralized surfaces were treated with either NHA or CP, while 1 group was left with no treatment. Vickers microhardness of enamel and cementum were determined before demineralization, after demineralization, and after remineralization. Analysis of variance and Tukey multiple comparisons were used to determine statistically significant differences at 95% level of confidence. Scanning electron microscopy and X-ray diffraction were used to evaluate for surface alterations.

Results

The mean ± SD of Vickers microhardness for before demineralization, after demineralization, and after remineralization for enamel and cementum were 377.37±22.99, 161.95±10.54, 161.70±5.92 and 60.37±3.81, 17.65±0.91, 17.04±1.00 for the no treatment group; 378.20±18.76, 160.72±8.38, 200.08±8.29 and 62.58±3.37, 18.38±1.33, 27.99±2.68 for the NHA groups; and 380.53±25.14, 161.94±5.66, 193.16±7.54 and 62.78±4.75, 19.07±1.30, 24.46±2.02 for the CP groups. Analysis of variance indicated significant increase in microhardness of demineralized enamel and cementum upon the application of either NHA or CP (p<0.05). Post hoc multiple comparisons indicated significantly higher remineralization capability of NHA for both enamel and cementum than CP (p<0.05), as evidenced by scanning electron microscopy, indicating NHA particle deposition in the area of remineralization, and crystallinity accumulation, as indicated by X-ray diffraction.

Conclusion

NHA gel and CP were capable of remineralization of the enamel and cementum. NHA was more capable in the remineralization process than CP. NHA was extremely capable in the remineralization process for enamel and cementum surrounding the margin of the computer-aided design and computer-aided manufacturing ceramic.