The natural history of periodontal disease in man. The rate of periodontal destruction before 40 years of age

Periodontal ageing and its management via pharmacological glucose modulation

Periodontal disease (PD), a widespread non-communicable disease, affects over 90% of the global population with no known cure. Current management strategies focus on the stabilisation of disease progression, which is successfully achieved to a limited extent. Yet the never-ending battle between bacteria and the gingiva involves a complex interplay between genetic, microbial and environmental factors, demanding innovative approaches to improve the prevention and stabilisation of this disease. Glucose is the body's source of energy and research has shown that dysregulation of the glucose metabolism impacts PD establishment and progression, as well as the development of systemic non-communicable diseases. Metformin, a drug known for its efficacy in diabetes treatment via controlling glucose metabolism, also demonstrated cardioprotective effects, increased longevity, and anti-inflammatory properties. Metformin has been used in gel format in clinical trials for non-surgical treatment of PD, however, its systemic use in normoglycemic individuals with PD is less explored. A recent study presented compelling evidence of metformin's preventive potential, impacting PD and markers of systemic health involved in metabolic health linked to improvement of lifespan. Therefore, this review discusses the aspects of ageing as a concept in the periodontium and the potential benefits of modulating glucose metabolism through metformin to prevent PD, indirectly preventing systemic conditions involved in multi-morbidity, addressing a critical gap in current management. It also examines the choice between implementation of behaviour change and/or medication as a strategy to add to current oral hygiene strategies. Finally, it discusses the ethical implications of prescribing systemic medication in dentistry.

Periodontitis and Outer Retinal Thickness: a Cross-Sectional Analysis of the United Kingdom Biobank Cohort

Purpose

Periodontitis, a ubiquitous severe gum disease affecting the teeth and surrounding alveolar bone, can heighten systemic inflammation. We investigated the association between very severe periodontitis and early biomarkers of age-related macular degeneration (AMD), in individuals with no eye disease.

Design

Cross-sectional analysis of the prospective community-based cohort United Kingdom (UK) Biobank.

Participants

Sixty-seven thousand three hundred eleven UK residents aged 40 to 70 years recruited between 2006 and 2010 underwent retinal imaging.

Methods

Macular-centered OCT images acquired at the baseline visit were segmented for retinal sublayer thicknesses. Very severe periodontitis was ascertained through a touchscreen questionnaire. Linear mixed effects regression modeled the association between very severe periodontitis and retinal sublayer thicknesses, adjusting for age, sex, ethnicity, socioeconomic status, alcohol consumption, smoking status, diabetes mellitus, hypertension, refractive error, and previous cataract surgery.

Main Outcome Measures

Photoreceptor layer (PRL) and retinal pigment epithelium-Bruch's membrane (RPE-BM) thicknesses.

Results

Among 36 897 participants included in the analysis, 1571 (4.3%) reported very severe periodontitis. Affected individuals were older, lived in areas of greater socioeconomic deprivation, and were more likely to be hypertensive, diabetic, and current smokers (all P < 0.001). On average, those with very severe periodontitis were hyperopic (0.05 ± 2.27 diopters) while those unaffected were myopic (-0.29 ± 2.40 diopters, P < 0.001). Following adjusted analysis, very severe periodontitis was associated with thinner PRL (-0.55 μm, 95% confidence interval [CI], -0.97 to -0.12; P = 0.022) but there was no difference in RPE-BM thickness (0.00 μm, 95% CI, -0.12 to 0.13; P = 0.97). The association between PRL thickness and very severe periodontitis was modified by age (P < 0.001). Stratifying individuals by age, thinner PRL was seen among those aged 60 to 69 years with disease (-1.19 μm, 95% CI, -1.85 to -0.53; P < 0.001) but not among those aged < 60 years.

Conclusions

Among those with no known eye disease, very severe periodontitis is statistically associated with a thinner PRL, consistent with incipient AMD. Optimizing oral hygiene may hold additional relevance for people at risk of degenerative retinal disease.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

The wingspan suspension approach: A modified semilunar technique for multiple areas of recession

BACKGROUND

Gingival recession can be considered an undesirable condition that results in the exposure of the root surface. There are many techniques that can be employed to address gingival recession; however, they frequently involve a second surgical site. Other approaches have been introduced in the past to address this concern, and this case study discusses the use of a modified technique to achieve root coverage.

METHODS

A patient presented to the periodontics clinic with concerns regarding gingival recession. A modification to the semilunar technique was employed to address the recession, whereas double sling sutures were utilized to maintain the coronal repositioning of the flap.

RESULTS

Maxillary central incisors initially presented with 2-3 mm of facial recession and root coverage was achieved by use of a modified surgical semilunar approach. No rebound noted over a 6-month period, newly established gingival margin deemed clinically stable.

CONCLUSIONS

This case study provides an alternative to addressing gingival recession in the maxillary anterior region, when <3 mm of recession is noted. Avoidance of a second surgical procedure and/or donor site is of particular benefit, as well as maintenance of the blood supply.

KEY POINTS

Why is this case new information? There is insufficient evidence on the use of a modified wingspan incision design Phenotype modification with elimination of a second surgical site is most ideal for the patient. What are the keys to successful management of this case? Comprehensive diagnosis and proper case selection Meticulous flap management and adequate release to allow for repositioning without tension Appropriate use ofsuture and suturing technique. What are the primary limitations to success in this case? Thin periodontal phenotype Poor oral hygiene and plaque accumulation postoperatively Loss to follow-up.

Natural history of periodontal disease: The original Sri Lanka and Oslo studies

Susceptibility to periodontal disease depends on individual factors within the host response to the bacterial challenge. The study of these factors requires longitudinal studies of an undisturbed development of the disease process. On the basis of the original longitudinal studies on the natural histology of periodontal disease staged in Sri Lanka and Oslo/Norway, several analyses of periodontal parameters and tooth status have been performed. The main findings were that in the first 20 years of complete absence of oral hygiene practices or preventive services attachment was lost at various rates. Three groups of subjects could be identified: rapidly progressing (RP) (8%), moderately progressing (MP) (81%), and subjects with no disease progression (NP) (11%). In the second two decades, the RP subjects have lost most of their teeth and no NP patients were identified anymore. The progression rate in these two decades was much slower, and the tooth mortality decreased. It could be predicted that subjects who had lost more than 2 mm at age 30 would not maintain a functional dentition at age 60. The corresponding control population in Oslo was used to study the influence of gingival inflammation on the initiation and progression of periodontal disease. The pattern and rates of attachment loss were identified in a population that was exposed to optimal and regular preventive services from age 3 onward. In the observation period of 26 years, it could be demonstrated that gingival inflammation varied little throughout adult life and always bleeding sites occurred consistently in 10% to 20%. The role of ongoing gingivitis in the pathogenesis of attachment loss was identified and also reflected stability whenever it was absent. Tooth mortality was only found in subjects with ongoing gingivitis. After 50 years of tooth age, 63% of the teeth were still maintained, while 99.8% were maintained after 50 years when gingival inflammation had been absent. Consequently, continuous gingivitis represented a risk factor for tooth loss.

Decreased bone mineral density is associated with an increased number of teeth with periodontitis progression: a 5-year retrospective cohort study

OBJECTIVE

Longitudinal studies on the systemic bone loss-periodontitis relationship are limited with disparate results. The aim of this study was to investigate the association between bone mineral density (BMD) and periodontitis progression, controlling for other covariables in a Thai population.

MATERIALS AND METHODS

In 2,418 participants, BMD values of the lumbar spine, femoral neck, and total hip were measured with dual-energy X-ray absorptiometry at baseline. Each participant's BMD status was classified as normal, osteopenia, or osteoporosis. Full mouth periodontal examinations on 6 sites/tooth were performed at baseline and 5-year follow-up visits. Periodontitis progression was defined as a tooth presenting an additional proximal CAL loss of ≥ 3 mm or an additional lost tooth with a baseline CAL ≥ 5 mm. The risk effects of BMD status on the number of teeth with periodontitis progression were analyzed using multivariate Poisson regression.

RESULTS

Baseline BMD status of osteoporosis was associated with an increased number of teeth with periodontitis progression in the subgroups of postmenopausal women, non-smokers, and participants with periodontitis stage III/IV with adjusted risk ratios of 1.31 (95% CI = 1.09-1.58), 1.19 (95% CI = 1.04-1.36), and 1.13 (95% CI = 1.00-1.28), respectively.

CONCLUSION

Baseline BMD in the osteoporosis range increased the risk of having a greater number of teeth with periodontitis progression in specific participant subgroups.

CLINICAL RELEVANCE

Decreased BMD is a potential factor affecting periodontitis progression risk in some individuals. Multidisciplinary approaches in educating and maintaining patients' bone-oral health may help improve their quality of life.

Furcation area and root proximity of molars as a risk indicator of periodontitis: a cone‑beam computed tomography-based study

OBJECTIVES

This study assessed the root proximity in molars and the furcation area (FA) in the first root separation point (RSP) using cone‑beam computed tomography (CBCT) and evaluated the association between the furcation area of molars and periodontal status of the patients.

METHODS

A total of 264 molar teeth in 66 participants were included in the study. The control group consisted of 110 molar teeth of participants, and 154 molar teeth were included in periodontitis group, which consisted of only stage II and III periodontitis patients. FA, RSP, and root proximities were measured in axial slices, and bone resorption rates were measured in sagittal slices.

RESULTS

Both maxillary and mandibular molar groups had significantly less FA in periodontitis group than in controls (p < 0.005), and there were significant relationships between the degree of bone resorption in molars and FA and furcation grades (p < 0.001). According to regression analysis, the risk of periodontitis increased by 1.011 times as total FA decreased (p < 0.001), and periodontitis risk of maxillary molar was 1.693 times higher than mandibular molars but not found to be statistically significant (p = 0.152). When assessing the root proximity between molar teeth, maxillary molars showed significantly higher root proximity in CEJs than mandibular molars in both periodontitis and control groups (p < 0.05).

CONCLUSIONS

The results indicate that the association between FA and the degree of bone resorption and root proximity of maxillary molars might be considered as a risk indicator for bone resorption in molars and might play a role during disease progression.

Identification of microbiological factors associated with periodontal health disparities

The present study aimed at identifying risk factors associated with periodontitis development and periodontal health disparities with emphasis on differential oral microbiota. The prevalence of periodontitis is recently rising dentate adults in the US, which presents a challenge to oral health and overall health. The risk of developing periodontitis is higher in African Americans (AAs), and Hispanic Americans (HAs) than in Caucasian Americans (CAs). To identify potentially microbiological determinations of periodontal health disparities, we examined the distribution of several potentially beneficial and pathogenic bacteria in the oral cavities of AA, CA, and HA study participants. Dental plaque samples from 340 individuals with intact periodontium were collected prior to any dental treatment, and levels of some key oral bacteria were quantitated using qPCR, and the medical and dental histories of participants were obtained retrospectively from axiUm. Data were analyzed statistically using SAS 9.4, IBM SPSS version 28, and R/RStudio version 4.1.2. Amongst racial/ethnic groups: 1) neighborhood medium incomes were significantly higher in the CA participants than the AA and the HA participants; 2) levels of bleeding on probing (BOP) were higher in the AAs than in the CAs and HAs; 3) Porphyromonas gingivalis levels were higher in the HAs compared to that in the CAs; 4) most P. gingivalis detected in the AAs were the fimA genotype II strain that was significantly associated with higher BOP indexes along with the fimA type IV strain. Our results suggest that socioeconomic disadvantages, higher level of P. gingivalis, and specific types of P. gingivalis fimbriae, particularly type II FimA, contribute to risks for development of periodontitis and periodontal health disparities.

Oral Health, Antimicrobials and Care for Patients With Chronic Oral Diseases – A Review of Knowledge and Treatment Strategies

Periodontal and chronic oral mucosal diseases are significant life impacting conditions which may co-exist and synergistically act to cause more severe and widespread oral pathology with enhanced challenges in effective management. Clinicians regularly observe these effects and struggle to effectively manage both problems in many patients. There is limited understanding of many basic and applied scientific elements underpinning potentially shared aetiopathological features and management. Recent developments in translational science provide an opportunity to greater improve knowledge and subsequently care for patients with these problems.

Systems Biology in Periodontitis

Systems biology is a promising scientific discipline that allows an integrated investigation of host factors, microbial composition, biomarkers, immune response and inflammatory mediators in many conditions such as chronic diseases, cancer, neurological disorders, and periodontitis. This concept utilizes genetic decoding, bioinformatic, flux-balance analysis in a comprehensive approach. The aim of this review is to better understand the current literature on systems biology and identify a clear applicability of it to periodontitis. We will mostly focus on the association between this condition and topics such as genomics, transcriptomics, proteomics, metabolomics, as well as contextualize delivery systems for periodontitis treatment, biomarker detection in oral fluids and associated systemic conditions.

Inflammation and Periodontal Regeneration

Technological innovations in cellular and molecular aspects of tissue engineering --scaffolds, stem cells and 3D printed tissues --have been dramatically increased in the last decade. However, regenerative treatment still has challenges in translation to clinic. This is partly due to failure of addressing an essential element of wound healing, inflammation. It is now well-recognized that inflammation is an active process. This paradigm shift opened up a new avenue of therapeutic approaches called "host-modulation." Host-modulation therapies capable of modulating inflammatory response at multiple levels and mimicking the natural sequence of wound healing offer a new direction and promising clinical translation.

Association between root taper and root proximity of single-rooted teeth with periodontitis: a cone-beam computed tomography based study

This study aimed to determine the association between the root taper and proximity of single-rooted teeth with periodontitis using cone-beam computed tomography (CBCT). CBCT images of 362 single-rooted teeth from 37 patients were evaluated. This case-control study analyzed 17 participants with stage II and III periodontitis, (n = 161 teeth, periodontitis group) and 20 participants with healthy periodontium (n = 201 teeth, control group). Multiplanar reconstructions were used for proximity measurements, and cross-sectional images for calculating the angle of the root tapers. Root proximity, root length, and root taper were measured. Multivariate binary logistic regression analysis was used to determine association with periodontitis. In the periodontitis group, the upper lateral root-taper was 18.33° ± 3.25° and was significantly higher when compared to the control group (p = 0.001). The root taper of the lateral incisor was associated with the diagnosis of periodontitis (p = 0.01) with an odds ratio of 1.541 according to regression analysis. Root length was also identified as a potential protective parameter. The risk of being diagnosed with periodontitis decreases when root length increases by 0.785 times (p = 0.043). Upper canines in the periodontitis group presented shorter root lengths (p = 0.039) and higher root tapers (p = 0.01). Also, mandibular canines were closer form adjacent teeth in the periodontitis group (p = 0.042). This study indicated that short-root and increased root-taper at specific teeth could be considered as risk indicators for periodontitis.

Tooth loss and radiographic bone loss in patients without regular supportive care: A retrospective study

BACKGROUND

Very few studies have investigated the effect of patient and site factors on periodontal progression and long-term tooth loss in populations with minimal dental care. The aim of this retrospective study was to assess tooth loss and radiographic bone loss over at least 5 years in patients attending a national-health service primary care practice in Sicily and undergoing no regular care.

METHODS

Records of two hundred consecutive patients with at least 5 years follow-up were screened and demographic, clinical and radiographic data were retrieved. Analyses of associations between patient and site factors and tooth loss were performed.

RESULTS

After excluding not suitable patients, a total of 159 patient records with clinical and radiographic data with average 8.6 years follow-up were included. One hundred of these patients had no professional mechanical plaque removal (PMPR) carried out throughout the study follow-up. Nearly 65% of patients lost at least 1 tooth during the follow-up period, with a total of 400 extracted teeth (for periodontal and non-periodontal reasons). The annual tooth loss rate was slightly higher for "no PMPR" (untreated) patients (0.30 teeth/patient/year) compared with patients who had PMPR (0.27 teeth/patient/year). On a patient-level, only reduced frequency of daily tooth brushing was associated with tooth loss at logistic regression, whereas staging, grading and diagnosis of caries were associated with rates of tooth loss/year. At multilevel analysis including patient- and tooth-factors, age, diagnosis of caries and endodontic disease and percentage of bone loss at baseline were associated with tooth loss.

CONCLUSION

This study confirms the importance of tooth brushing, initial bone loss, caries and endodontic disease in predicting tooth survival in a primary care setting.

Periodontal disease progression in the second half of life and following a single episode of scaling and root planing-A clinical study in the Sri Lankan tea plantation cohort with documented clinical parameters over more than 40 years

BACKGROUND

To evaluate periodontal disease progression (PDP) and potentially detectable effects of a single episode of scaling and root planing (se-SRP) in subjects lacking professional dental care and oral hygiene practices for >40 years.

METHODS

In 2013, se-SRP was offered to all available subjects from the original cohort of 480 males initially established in 1970. From a total of 75 attending the previous examination in 2010 (baseline), 27 consented to receive the intervention while 18 declined and served as controls. Clinical data were recorded again in 2014 (follow-up) similarly to the previous surveys (1970 to 2010).

RESULTS

Subjects' mean age in 2010 was 62.5 (± 3.6, test) and 61.9 (± 3.8, control) years. At follow-up, both groups presented with elevated tooth loss of 1.2 (from 15.5 ± 9.0, test) and 1.5 (from 17.9 ± 6.6, control) resulting in 1,392 (test) and 1,061 (control) sites available for further analysis. In both groups, clinical attachment level (CAL) loss and probing depths (PD) deteriorated. PD increase of 0.22 mm (± 1.70) in the test group was significantly higher compared with the control group (0.08 mm ± 1.30) (P <0.0001) demonstrating unaffected PDP. Computed estimates of further PDP revealed CAL and PD reductions in subjects aged ≥40 years. Specifically, the latter was positively correlated with tooth loss in subjects aged ≥40 years (P = 0.69, P = 0.0012) and ≥50 years (r = 0.62, P <0.0001).

CONCLUSION

se-SRP in previously untreated periodontitis subjects aged ≥50 years may be ineffective in reducing PDP thus demanding advanced preventive measures, treatment in the first half of life, and sustained access to supportive care.

Do periodontal defects affect periodontal inflammation and destruction? Histological/microbiological changes and gene expression profiles of a pilot study in beagle dogs

BACKGROUND

The present study focused on the inflammatory disease progress after periodontal defect induction and aimed to specifically determine periodontal tissue responses following dental plaque accumulation by ligatures on a site with/without standardized periodontal defect induction.

METHODS

After 1 month from extraction of the adjacent teeth, semi-circumferential defects were surgically created in the unilateral second and fourth premolars (test group), whereas no defects were being induced at the contralateral sites (control group). One week later, silk was used to ligate the tooth cervix at both sites to encourage the accumulation of dental plaque. Four weeks later, the tissue samples were collected for histological/histomorphometric and microarray analysis. Microbiological analysis was performed before defect induction and at ligatures, and after 4 weeks of dental plaque accumulation.

RESULTS

Remarkable inflammation was clinically and histologically observed in both groups after plaque accumulation, and the intrabony type of periodontal defect exaggerated inflammatory cell infiltration into the connective tissue layer. Expression of genes related to inflammation such as IL-1 was highly up-regulated in test sites. However, these inflammatory infiltrations did not invade to a boundary of periodontal ligament and connective tissue attachment in both groups, and histomorphometric results corresponds to these observational results. Bacterial findings also showed no significant differences in detected microbiome compositions between control and test groups at three-time points.

CONCLUSION

Intrabony defect might exaggerate the plaque-induced inflammation in the aspect of inflammatory cell infiltration and the related gene expression, but both dental plaque and the pre-existing periodontal defect negligibly disrupt periodontal attachment and the underlying alveolar bone.

Contour changes of peri-implant tissues are minimal and similar for a one- and a two-piece implant system over 12 years

Objectives

To assess contour changes of peri-implant tissues comparing a one- and a two-piece dental implant system over 12 years.

Materials and methods

Patients seeking implant therapy were enrolled and randomly allocated to receive implants (a one-piece (STM) or a two-piece (BRA) system). Impressions were taken at the time of insertion of the final reconstruction (BL), after 1 year (FU-1), 5 years (FU-5), and at 12 years (FU-12). Thirty patients were included in the analysis (STM, 16; BRA, 14). Digital scans of casts were superimposed and analyzed in an image analysis program. Measurements included changes of the crown height, contour changes on the buccal side of the implants and the contralateral teeth (control).

Results

Contour changes at implant sites revealed a loss of − 0.29 mm (STM) and − 0.46 mm (BRA) during an observation period of 12 years. Contour changes at the corresponding tooth sites amounted to − 0.06 mm (STM) and − 0.12 mm (BRA) during the same time period. The implant crown gained 0.25 mm (STM) and 0.08 mm (BRA) in height due to recession of the marginal mucosa. The corresponding gain in crown height at the contralateral tooth sites amounted to 0.36 mm (STM) and 0.10 mm (BRA). Interproximal marginal bone level changes measured − 0.28 mm (STM) and − 1.11 mm (BRA). The mean BOP amounted to 38.8% (STM) and 48.7% (BRA) at the 12-year follow-up (FU-12).

Conclusion

Minimal changes of the peri-implant soft tissue contour were observed at implant sites over the period of 12 years irrespective of the use of a one- or a two-piece implant system. The differences between the implant sites and corresponding teeth were clinically negligible.

Clinical relevance

Peri-implant soft tissue stability is of high clinical relevance when monitoring dental implant sites on the long run. Clinical data on the extent of soft tissue changes around different implant systems are scarce. The present RCTs demonstrate minimal changes of the peri-implant soft tissue contour 12 years after implant insertion independent of the use of a one- or a two-piece implant system.

A public health approach for prevention of periodontal disease

Upwards of 1 in 10 adults worldwide may be affected by severe periodontitis, making the disease more prevalent than cardiovascular disease. Despite its global scope, its impact on pain, oral function, and the wellbeing of individuals, and the disproportionate burden of disease and the socioeconomic impact on communities, the perception that periodontal disease is a public health problem remains low. Although there have been substantial improvements in our understanding of the etiology of periodontal disease and how we can prevent and control it, these advances have been primarily focused on individual, patient-focused approaches. The prevention of periodontal disease depends on improving currently available individual interventions and on determining what public health interventions can be effective and sustainable under real-life conditions. Currently, public health approaches for periodontal disease prevention and control are lacking. This review traces the historical strategies for prevention of periodontal disease in an epidemiologic transition context, using a modified model developed for cardiovascular disease, and presents a possible public health approach. Improving periodontal disease prevention and control will need to take into consideration the core activities of a public health approach: assessment, policy development, and assurance.

Current concepts and an alternative perspective on periodontal disease

BACKGROUND

Epidemiological data from countries worldwide show a consistent pattern implying that a fraction of around 10% of those over 40-50 years in all populations will exhibit severe periodontitis with the potential risk of losing teeth during their life-time. The subgingival microbiota shows striking similarities between populations irrespective of disease severity and can only marginally explain the clinical pattern. It is also difficult to explain this pattern by genetic and acquired risk factors such as systemic disease (e.g. diabetes) or habits (e.g. smoking) even if they may have a confounding effect on the disease.

MAIN TEXT

Inflammation of the gingiva appears to be a normal and physiological response to the presence of commensal bacteria along the gingival crevice and in the dental biofilm. Over many years of exposure to the dental biofilm, the chronic inflammation in the gingiva gradually results in a loss of attachment and bone loss. Numerous laboratory and clinical studies have provided insight into the potential role of determinants that are associated with periodontitis. However, it has been difficult to relate the findings to the pattern of the distribution of the disease observed in epidemiological studies. We propose a simple and parsimonious model that considers all the multitude of potential determinants as creating effectively random noise within the dental biofilm to which the tissues react by accumulating the effects of this noise.

CONCLUSIONS

We suggest that such a model can explain many of the epidemiological features of periodontal breakdown over time, and we discuss its clinical implications.

Periodontal inflammation: Integrating genes and dysbiosis

Biofilm bacteria co‐evolve and reach a symbiosis with the host on the gingival surface. The disruption of the homeostatic relationship between plaque bacteria and the host can initiate and promote periodontal disease progression. Recent advances in sequencing technologies allow researchers to profile disease‐associated microbial communities and quantify microbial metabolic activities and host transcriptional responses. In addition to confirming the findings from previous studies, new putative pathogens and novel genes that have not previously been associated with periodontitis, emerge. For example, multiple studies have reported that Synergistetes bacteria are associated with periodontitis. Genes involved in epithelial barrier defense were downregulated in periodontitis, while excessive expression of interleukin‐17 was associated with a hyperinflammatory response in periodontitis and with a unique microbial community. Bioinformatics‐enabled gene ontology pathway analyses provide a panoramic view of the bacterial and host activities as they shift from periodontal health to disease. Additionally, host innate factors, such as genetic variants identified by either a candidate‐gene approach or genome‐wide association analyses, have an impact on subgingival bacterial colonization. Transgenic mice carrying candidate genetic variants, or with the deletion of candidate genes mimicking the deleterious loss‐of‐function variant effect, provide experimental evidence validating the biologic relevance of the novel markers associated with the microbial phenotype identified through a statistical approach. Further refinement in bioinformatics, data management approaches, or statistical tools, are required to gain insight into host‐microbe interactions by harmonizing the multidimensional “big” data at the genomic, transcriptional, and proteomic levels.

Peri-implantitis

OBJECTIVES

This narrative review provides an evidence-based overview on peri-implantitis for the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.

METHODS

A literature review was conducted addressing the following topics: 1) definition of peri-implantitis; 2) conversion from peri-implant mucositis to peri-implantitis, 3) onset and pattern of disease progression, 4) characteristics of peri-implantitis, 5) risk factors/indicators for peri-implantitis, and 6) progressive crestal bone loss in the absence of soft tissue inflammation.

CONCLUSIONS

1)Peri-implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant connective tissue and progressive loss of supporting bone. 2)The histopathologic and clinical conditions leading to the conversion from peri-implant mucositis to peri-implantitis are not completely understood. 3)The onset of peri-implantitis may occur early during follow-up and the disease progresses in a non-linear and accelerating pattern. 4a)Peri-implantitis sites exhibit clinical signs of inflammation and increased probing depths compared to baseline measurements. 4b)At the histologic level, compared to periodontitis sites, peri-implantitis sites often have larger inflammatory lesions. 4c)Surgical entry at peri-implantitis sites often reveals a circumferential pattern of bone loss. 5a)There is strong evidence that there is an increased risk of developing peri-implantitis in patients who have a history of chronic periodontitis, poor plaque control skills, and no regular maintenance care after implant therapy. Data identifying "smoking" and "diabetes" as potential risk factors/indicators for peri-implantitis are inconclusive. 5b)There is some limited evidence linking peri-implantitis to other factors such as: post-restorative presence of submucosal cement, lack of peri-implant keratinized mucosa and positioning of implants that make it difficult to perform oral hygiene and maintenance. 6)Evidence suggests that progressive crestal bone loss around implants in the absence of clinical signs of soft tissue inflammation is a rare event.

Peri-implantitis

OBJECTIVES

This narrative review provides an evidence-based overview on peri-implantitis for the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.

METHODS

A literature review was conducted addressing the following topics: 1) definition of peri-implantitis; 2) conversion from peri-implant mucositis to peri-implantitis, 3) onset and pattern of disease progression, 4) characteristics of peri-implantitis, 5) risk factors/indicators for peri-implantitis, and 6) progressive crestal bone loss in the absence of soft tissue inflammation.

CONCLUSIONS

1)Peri-implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant connective tissue and progressive loss of supporting bone. 2)The histopathologic and clinical conditions leading to the conversion from peri-implant mucositis to peri-implantitis are not completely understood. 3)The onset of peri-implantitis may occur early during follow-up and the disease progresses in a non-linear and accelerating pattern. 4a)Peri-implantitis sites exhibit clinical signs of inflammation and increased probing depths compared to baseline measurements. 4b)At the histologic level, compared to periodontitis sites, peri-implantitis sites often have larger inflammatory lesions. 4c)Surgical entry at peri-implantitis sites often reveals a circumferential pattern of bone loss. 5a)There is strong evidence that there is an increased risk of developing peri-implantitis in patients who have a history of chronic periodontitis, poor plaque control skills, and no regular maintenance care after implant therapy. Data identifying "smoking" and "diabetes" as potential risk factors/indicators for peri-implantitis are inconclusive. 5b)There is some limited evidence linking peri-implantitis to other factors such as: post-restorative presence of submucosal cement, lack of peri-implant keratinized mucosa and positioning of implants that make it difficult to perform oral hygiene and maintenance. 6)Evidence suggests that progressive crestal bone loss around implants in the absence of clinical signs of soft tissue inflammation is a rare event.

Longitudinal evaluation of periodontitis and tooth loss among older adults

AIM

To evaluate pattern of change in periodontal variables and tooth loss in a twelve-year follow-up study of older adults living in Sweden.

METHODS

In a prospective population study of older adults, a clinical examination and radiographic dental examination were performed at baseline (2001-2003) and after 12 years (2013-2015). In 375 individuals, the number and proportion of sites with a distance ≥4 mm and ≥5 mm from cemento-enamel junction to the bone level, the number and proportion of teeth with pockets ≥5 mm and number of teeth lost were calculated. Dental caries was registered. Periodontitis was defined as having ≥2 sites with ≥5 mm distance from cemento-enamel junction to the marginal bone level and ≥1 tooth with pockets ≥5 mm.

RESULTS

A diagnosis of periodontitis was evident in 39% of the individuals, and 23% of the individuals lost ≥3 teeth over the study period. The proportion of sites with ≥4 mm and ≥5 mm bone loss increased with age, while the proportion of teeth with pockets remained stable. Periodontitis was the strongest predictor for losing ≥3 teeth, OR 2.9 (p < .001) in the final model.

CONCLUSIONS

Periodontitis is a risk factor for future tooth loss among older adults.

Association between Periodontitis and Metabolic Syndrome in a Korean Nationally Representative Sample of Adults Aged 35-79 Years

This study aimed to evaluate the association between periodontitis and metabolic syndrome (MetS) and to investigate risk factors associated with MetS in Korean adults aged 35 to 79 years. Among individuals aged 35-79 years who participated in the Korea National Health and Nutrition Examination Survey 2013-2015, 8314 participants who completed the required examinations and questionnaires were included. Confounding variables related to demographic and socioeconomic status and systemic and oral health-related behaviors were age, gender, household income, education level, smoking, alcohol intake, physical activity, and frequency of daily toothbrushing. Of the 8314 participants, 32.2% were diagnosed with MetS. The prevalence of MetS was 26.6% and 41.6% in those without and with periodontitis, respectively. Among individuals with periodontitis, the prevalence of MetS was 44.3% in males and 36.9% in females. Compared to non-periodontitis, periodontitis was associated with MetS (adjusted OR = 1.422, 95% CI: 1.26-1.61). Age, frequency of daily toothbrushing, and periodontitis were associated with MetS in both males and females. While current smoking and alcohol intake more than twice a week were significantly associated with MetS in males, household income and education level were significantly associated with MetS in females. The findings suggest that periodontitis can be associated with MetS.

Interleukin-1 Genotype in Periodontitis

This paper presents the current knowledge concerning the role of polymorphisms of IL1A and IL1B genes in periodontitis. Attention has been paid to the role of IL-1 in the pathogenesis of the disease, and to the significance of a genetic test, investigating the presence of composite two polymorphisms of IL-1 gene, as a risk factor for severe periodontitis. The significance of this test for prevention of periodontitis and its therapy has been discussed. IL-1 polymorphisms have been presented and described according to the reference single nucleotide polymorphism (SNP) identification number (rsID), established to eradicate the redundancy of reported polymorphisms in the SNP database processed by the National Center for Biotechnology Information. The prevalence of these genotypes in different populations and ethnic groups and its effect on periodontal health have been discussed. The presented data show inconsistent results. It seems that at least two polymorphisms, rs1800587 and rs1143634, are associated with periodontal inflammation. Therefore, they can be regarded as candidate genes involved in further periodontitis risk assessment. It seems that geographical and ethnical factors can play a great role, as the prevalence of specific polymorphisms varies greatly depending on the population studied.

Contemporary approaches for identifying individual risk for periodontitis

Key breakthroughs in our understanding of the etiology and principles of predictable treatment of patients with chronic periodontitis first emerged in the late 1960s and carried on into the mid-1980s. Unfortunately, some generalizations of the evidence led many to believe that periodontitis was a predictable result of exposure to bacterial plaque accumulations over time. For a brief period, the initial plaque concept was translated by some to implicate specific bacterial infections, with both concepts (plaque exposure and specific infection) being false assumptions that led to clinical outcomes which were frustrating to both the clinician and the patient. The primary misconceptions were that every individual was equally susceptible to periodontitis, that disease severity was a simple function of magnitude of bacterial exposure over time, and that all patients would respond predictably if treated based on the key principles of bacterial reduction and regular maintenance care. We now know that although bacteria are an essential initiating factor, the clinical severity of periodontitis is a complex multifactorial host response to the microbial challenge. The complexity comes from the permutations of different factors that may interact to alter a single individual's host response to challenge, inflammation resolution and repair, and overall outcome to therapy. Fortunately, although there are many permutations that may influence host response and repair, the pathophysiology of chronic periodontitis is generally limited to mild periodontitis with isolated moderate disease in most individuals. However, approximately 20%-25% of individuals will develop generalized severe periodontitis and probably require more intensive bacterial reduction and different approaches to host modulation of the inflammatory outcomes. This latter group may also have serious systemic implications of their periodontitis. The time appears to be appropriate to use what we know and currently understand to change our approach to clinical care. Our goal would be to increase our likelihood of identifying those patients who have a more biologically disruptive response combined with a more impactful microbial dysbiosis. Current evidence, albeit limited, indicates that for those individuals we should prevent and treat more intensively. This paper discusses what we know and how we might use that information to start individualizing risk and treat some of our patients in a more targeted manner. In my opinion, we are further along than many realize, but we have a great lack of prospective clinical evidence that must be accumulated while we continue to unravel the contributions of specific mechanisms.

Risk indicators for prevalence, extent and severity of periodontitis among rural Indian population aged 35-54 years

AIMS

This study aimed to identify risk indicators associated with periodontitis and the contribution of each of the indicators towards the prevalence, extent and severity of periodontitis in a rural Indian population.

METHODS

A cross-sectional study design was used to collect data according to National Survey of Adult Oral Health Australia guidelines. A multistage stratified random sampling was followed to select 1401 participants, who were in the age group of 35-54 years. The participants were selected from 50 villages belonging to the 5 sub-provinces of 2 Indian districts. Data were collected through face-to-face interviews and oral examination. Statistical analysis was performed using SAS version 9.3. The univariate, bivariate and multivariate analyses were performed to determine the risk indicators of prevalence, extent and severity of periodontitis. Population attributable fraction was estimated for each of the significant risk indicators of prevalence and extent.

RESULTS

In this study, factors such as age, education, tobacco chewing and plaque accumulation were significantly associated with the prevalence of periodontitis. Age, socioeconomic status, method of tooth cleaning, alcohol consumption and plaque accumulation were significant risk indicators for generalized periodontitis. Age, tobacco chewing and plaque were associated with severity of periodontitis in the population.

CONCLUSION

The rural population had a high prevalence of periodontitis. Sociodemographic factors, poor oral hygiene, tobacco and alcohol were the main risk indicators attributable to periodontitis.

Oral Health and Quality of Life in Candidates for Liver Transplantation

BACKGROUND

There is a gap in the scientific literature about the association between oral health and the health-related quality of life of patients on the liver transplantation waiting list. The aim of this work was to describe aspects of oral health and quality of life of patients on a liver transplantation waiting list.

METHODS

This was a cross-sectional study among 116 patients with chronic hepatic disease: 29 on a liver transplantation waiting list (Model for End-Stage Liver Disease score ≥15) and 87 under monitoring in a gastroenterology service in a Brazilian university hospital. Oral health was evaluated according to criteria recommended by the World Health Organization and by the European Association of Dental Public Health. Health-related quality of life was evaluated by means of the 36-Item Short-Form Health Survey (SF-36).

RESULTS

Patients on the liver transplantation waiting list presented poorer health-related quality of life than those who were not on the list in the domains physical functioning, role physical, bodily pain, general health perceptions, and social functioning and in the physical component summary. Periodontitis affected 72.4% of the patients on the liver transplantation waiting list, but only 27.6% of the patients not on that list. Reduced salivary flow was associated with poorer mental health component summary in hepatitis C patients.

CONCLUSIONS

Patients on the liver transplantation waiting list presented poorer health-related quality of life than those who were not on the list, mainly in the indicators concerning physical health, as well as higher frequencies of decayed teeth and periodontitis. The mental health component summary was associated with reduced salivary flow in hepatitis C patients.

Site-level progression of periodontal disease during a follow-up period

Periodontal disease is assessed and its progression is determined via observations on a site-by-site basis. Periodontal data are complex and structured in multiple levels; thus, applying a summary statistical approach (i.e., the mean) for site-level evaluations results in loss of information. Previous studies have shown the availability of mixed effects modeling. However, clinically beneficial information on the progression of periodontal disease during the follow-up period is not available.

We conducted a multicenter prospective cohort study. Using mixed effects modeling, we analyzed 18,834 sites distributed on 3,139 teeth in 124 patients, and data were collected 5 times over a 24-month follow-up period. The change in the clinical attachment level (CAL) was used as the outcome variable. The CAL at baseline was an important determinant of the CAL changes, which varied widely according to the tooth surface. The salivary levels of periodontal pathogens, such as Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, were affected by CAL progression. “Linear”- and “burst”-type patterns of CAL progression occurred simultaneously within the same patient. More than half of the teeth that presented burst-type progression sites also presented linear-type progression sites, and most of the progressions were of the linear type. Maxillary premolars and anterior teeth tended to show burst-type progression. The parameters identified in this study may guide practitioners in determining the type and extent of treatment needed at the site and patient levels. In addition, these results show that prior hypotheses concerning "burst" and "linear" theories are not valid.

Patterns of periodontal disease progression based on linear mixed models of clinical attachment loss

AIM

The goal of the present longitudinal cohort study was to examine patterns of periodontal disease progression at progressing sites and subjects defined based on linear mixed models (LMM) of clinical attachment loss (CAL).

MATERIALS AND METHODS

A total of 113 periodontally healthy and 302 periodontitis subjects had their CAL calculated bimonthly for 12 months. LMMs were fitted for each site and the predicted CAL levels used to categorize their progression state. Participants were grouped based on the number of progressing sites into unchanged, transitional and active subjects. Patterns of periodontal disease progression were explored using descriptive statistics.

RESULTS

Progression occurred primarily at molars (50% of progressing sites) and inter-proximal sites (72%), affected a higher proportion of deep than shallow sites (2.7% versus 0.7%), and pocketing was the main mode of progression (49%). We found a low level of agreement (47%) between the LMM and traditional approaches to determine progression such as change in CAL ≥3 mm. Fourteen per cent of subjects were classified as active and among those 93% had periodontitis. The annual mean rate of progression for the active subjects was 0.35 mm/year.

CONCLUSION

Progressing sites and subjects defined based on LMMs presented patterns of disease progression similar to those previously reported in the literature.

Natural history of periodontitis: Disease progression and tooth loss over 40 years

OBJECTIVES

To assess long-term attachment and periodontitis-related tooth loss (PTL) in untreated periodontal disease over 40 years.

MATERIAL AND METHODS

Data originated from the natural history of periodontitis study in Sri Lankan tea labourers first examined in 1970. In 2010, 75 subjects (15.6%) of the original cohort were re-examined.

RESULTS

PTL over 40 years varied between 0 and 28 teeth (mean 13.1). Four subjects presented with no PTL, while 12 were edentulous. Logistic regression revealed attachment loss as a statistically significant covariate for PTL (p < .004). Markov chain analysis showed that smoking and calculus were associated with disease initiation and that calculus, plaque, and gingivitis were associated with loss of attachment and progression to advanced disease. Mean attachment loss <1.81 mm at the age of 30 yielded highest sensitivity and specificity (0.71) to allocate subjects into a cohort with a dentition of at least 20 teeth at 60 years of age.

CONCLUSIONS

These results highlight the importance of treating early periodontitis along with smoking cessation, in those under 30 years of age. They further show that calculus removal, plaque control, and the control of gingivitis are essential in preventing disease progression, further loss of attachment and ultimately tooth loss.

The Sex and Gender Intersection in Chronic Periodontitis

Periodontitis, a complex polymicrobial inflammatory disease, is a public health burden affecting more than 100 million people and being partially responsible for tooth loss. Interestingly, periodontitis has a documented higher prevalence in men as compared to women signifying a possible sex/gender entanglement in the disease pathogenesis. Although relevant evidence has treated sex/gender in a simplistic dichotomous manner, periodontitis may represent a complex inflammatory disease model, in which sex biology may interfere with gender social and behavioral constructs affecting disease clinical phenotype. Even when it became clear that experimental oral health research needed to incorporate gender (and/or sex) framework in the hypothesis, researchers overwhelmingly ignored it unless the research question was directly related to reproductive system or sex-specific cancer. With the recognition of gender medicine as an independent field of research, this study challenged the current notion regarding sex/gender roles in periodontal disease. We aimed to develop the methodological and analytical framework with the recognition of sex/gender as important determinants of disease pathogenesis that require special attention. First, we aim to present relevant sex biologic evidence to understand the plausibility of the epidemiologic data. In periodontitis pathogenesis, sex dimorphism has been implicated in the disease etiology possibly affecting the bacterial component and the host immune response both in the innate and adaptive levels. With the clear distinction between sex and gender, gender oral health disparities have been explained by socioeconomic factors, cultural attitudes as well as access to preventive and regular care. Economic inequality and hardship for women have resulted in limited access to oral care. As a result, gender emerged as a complex socioeconomic and behavioral factor influencing oral health outcomes. Taken together, as disease phenotypic presentation is a multifactorial product of biology, behavior and the environment, sex dimorphism in immunity as well as gender socio-behavioral construct might play a role in the above model. Therefore, this paper will provide the conceptual framework and principles intergrading sex and gender within periodontal research in a complex biologic and socio-behavioral dimension.

Age threshold for moderate and severe periodontitis among Korean adults without diabetes mellitus, hypertension, metabolic syndrome, and/or obesity

The purpose of this study is to determine an appropriate age threshold at which to recommend the evaluation of moderate and severe periodontitis among Korean adults.This study involved a cross-sectional analysis using data from the Korean National Health and Nutrition Examination Survey from 2012 to 2014. Incidence rates of periodontitis with the 95% confidence interval (CI) were evaluated. The predictive accuracy of age for periodontitis was determined by calculating the area under curve (AUC) on the basis of the receiver operating characteristic (ROC) curve.The cutoff value of age was 43 years in men having periodontitis with an AUC of 0.70 with 95% CI of 0.69 to 0.72. The AUC was 0.72 (95% CI: 0.70-0.73), and the cutoff value of age (49 years) was identified for the moderate periodontitis in women. The cutoff values for age with AUCs and 95% CI for individuals with periodontitis were 46 years (0.72 [0.71-0.73]), 43 years (0.73 [0.72, 0.74]), 45 years (0.71 [0.70,0.72]), 43 years (0.73 [0.72, 0.74]), and 45 years (0.74 [0.72, 0.75]) for no obesity, no abdominal obesity, no diabetes mellitus, no hypertension, and no metabolic syndrome groups, respectively.This study proposed the guideline for the appropriate age threshold at which to recommend the evaluation of moderate and severe periodontitis for the general population and additionally added the guideline for the individuals without systemic disease including diabetes mellitus, hypertension, metabolic syndrome, and obesity. This study suggests that the participants with certain age may be recommended for the regular periodontal evaluation.

Potential Role of Free Fatty Acids in the Pathogenesis of Periodontitis and Primary Sjögren's Syndrome

Clinical studies have shown that metabolic disorders such as type 2 diabetes and dyslipidemia are associated with increased risk of oral-related diseases, such as periodontitis and Sjögren’s syndrome. Although changes in the immune system are critical in both of these metabolic disorders and oral-related diseases, the mechanism underlying the interaction between these diseases remains largely unknown. Obesity and type 2 diabetes are known to be associated with higher concentrations of free fatty acids in blood. Among free fatty acids, saturated fatty acids such as palmitic acid have been demonstrated to induce inflammatory responses mainly via the innate immune systems, and to be involved in the pathogenesis of type 2 diabetes in tissues such as adipose tissue, liver, pancreas, and skeletal muscle. Here, we highlight recent advances in evidence for the potential involvement of palmitic acid in the pathogenesis of periodontitis and Sjögren’s syndrome, and discuss the possibility that improvement of the lipid profile could be a new strategy for the treatment of these diseases.

Assessment of non-carious root surface defects in areas of gingival recession: A descriptive study

Background

The purpose of this descriptive study was to observe the distribution of four different classes of non-carious cervical root surface discrepancies in teeth with gingival recession. Additionally to explore the different treatment modalities in the literature for each of these defects.

Material and Methods

A total of 150 subjects with at least one labial gingival recession were included in the study. 1400 teeth were evaluated using 2.5 X magnification loupes and UNC -15 probe for the presence of the cemento-enamel junction and step like defects according to Pini-Prato’s classification: A-, identifiable CEJ without defect; A+, identifiable CEJ with defect; B-, unidentifiable CEJ without defect, B+, unidentifiable CEJ with defect. Further a comprehensive electronic and hand search of pubmed indexed journals was performed to identify appropriate treatment modalities for these defects and their predictability following restorative/surgical or combination of both.

Results

A total of 1400 teeth with exposed root surfaces were examined (793 Maxillary; 607 mandibular). 499 teeth were A-, 405 were A+, 322 were B+ and 174 were B-. The distribution of these defects in different teeth was: 36% premolars, 32% molars, 21% incisors and 11% canines, collectively 68% in the aesthetic zone.

Conclusions

Majority of these lesions are in the maxillary aesthetic zone. Hence the presence of the CEJ and the defect must be taken into account while managing these defects surgically.

Key words:Cervical abrasion, gingival recession, magnification loupes, root coverage, step defects.

Effects of triclosan on host response and microbial biomarkers during experimental gingivitis

AIM

This exploratory randomized, controlled clinical trial sought to evaluate anti-inflammatory and -microbial effects of triclosan during experimental gingivitis as assessed by host response biomarkers and biofilm microbial pathogens.

MATERIALS AND METHODS

Thirty participants were randomized to triclosan or control dentifrice groups who ceased homecare for 21 days in an experimental gingivitis (EG) protocol. Plaque and gingival indices and saliva, plaque, and gingival crevicular fluid (GCF) were assessed/collected at days 0, 14, 21 and 35. Levels and proportions of 40 bacterial species from plaque samples were determined using checkerboard DNA-DNA hybridization. Ten biomarkers associated with inflammation, matrix degradation, and host protection were measured from GCF and saliva and analysed using a multiplex array. Participants were stratified as "high" or "low" responders based on gingival index and GCF biomarkers and bacterial biofilm were combined to generate receiver operating characteristic curves and predict gingivitis susceptibility.

RESULTS

No differences in mean PI and GI values were observed between groups and non-significant trends of reduction of host response biomarkers with triclosan treatment. Triclosan significantly reduced levels of A. actinomycetemcomitans and P. gingivalis during induction of gingivitis.

CONCLUSIONS

Triclosan reduced microbial levels during gingivitis development (ClinicalTrials.gov NCT01799226).

Peri-implantitis - onset and pattern of progression

BACKGROUND

While information on the prevalence of peri-implantitis is available, data describing onset and progression of the disease are limited.

MATERIAL & METHODS

A 9-year follow-up examination of 596 randomly selected implant-carrying individuals identified 62 patients with moderate/severe peri-implantitis. Longitudinal assessments of peri-implant marginal bone levels were used to construct a statistical model with bone loss as the dependent variable. A multilevel growth model estimated the pattern of bone loss for each implant/patient. Onset of peri-implantitis was determined by evaluating the cumulative percentage of implants/patients presenting with estimated bone loss at each year following prosthesis delivery.

RESULTS

The analysis showed a non-linear, accelerating pattern of bone loss at the 105 affected implants. The onset of peri-implantitis occurred early, and 52% and 66% of implants presented with bone loss of >0.5 mm at years 2 and 3 respectively. A total of 70% and 81% of subjects presented with ≥1 implants with bone loss of >0.5 mm at years 2 and 3 respectively.

CONCLUSIONS

It is suggested that peri-implantitis progresses in a non-linear, accelerating pattern and that, for the majority of cases, the onset occurs within 3 years of function.

The Effect of Periodontitis on Expression of Interleukin-21: A Systematic Review

Purpose. Inflammation and tissue breakdown are led by an array of inflammatory destructive mediators associated with initiation and progression of inflammatory diseases like periodontitis. Current evidence shows that these inflammatory mediators have a definitive role in the pathogenesis of various systemic diseases with an inflammatory component. Interleukin-21 (IL-21) has been associated with systemic diseases like rheumatoid arthritis and Crohn's disease that follow a chronic inflammatory cascade. Similarly recent studies have associated Interleukin-21 levels with periodontitis. This systematic review was aimed to assess the levels of IL-21 in subjects with periodontitis. Methods. A complete literature search was done in PubMed, Medline, Science Direct, and Cochrane databases and Google Scholar based on the inclusion/exclusion criteria. Six relevant articles were procured. Full text was read individually by two reviewers and data extraction was done based on STROBE statement. Results. After data extraction five observational and one interventional study were obtained. All the studies showed an increased expression of IL-21 in periodontitis and the interventional study showed reduction in IL-21 levels after nonsurgical periodontal therapy (NSP). Conclusion. Interleukin-21 levels are higher in periodontitis than controls. With this limited evidence further longitudinal studies are required to consider this as a definitive inflammatory marker.

Host response mechanisms in periodontal diseases

Periodontal diseases usually refer to common inflammatory disorders known as gingivitis and periodontitis, which are caused by a pathogenic microbiota in the subgingival biofilm, including Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Treponema denticola that trigger innate, inflammatory, and adaptive immune responses. These processes result in the destruction of the tissues surrounding and supporting the teeth, and eventually in tissue, bone and finally, tooth loss. The innate immune response constitutes a homeostatic system, which is the first line of defense, and is able to recognize invading microorganisms as non-self, triggering immune responses to eliminate them. In addition to the innate immunity, adaptive immunity cells and characteristic cytokines have been described as important players in the periodontal disease pathogenesis scenario, with a special attention to CD4⁺ T-cells (T-helper cells). Interestingly, the T cell-mediated adaptive immunity development is highly dependent on innate immunity-associated antigen presenting cells, which after antigen capture undergo into a maturation process and migrate towards the lymph nodes, where they produce distinct patterns of cytokines that will contribute to the subsequent polarization and activation of specific T CD4+ lymphocytes. Skeletal homeostasis depends on a dynamic balance between the activities of the bone-forming osteoblasts (OBLs) and bone-resorbing osteoclasts (OCLs). This balance is tightly controlled by various regulatory systems, such as the endocrine system, and is influenced by the immune system, an osteoimmunological regulation depending on lymphocyte- and macrophage-derived cytokines. All these cytokines and inflammatory mediators are capable of acting alone or in concert, to stimulate periodontal breakdown and collagen destruction via tissue-derived matrix metalloproteinases, a characterization of the progression of periodontitis as a stage that presents a significantly host immune and inflammatory response to the microbial challenge that determine of susceptibility to develop the destructive/progressive periodontitis under the influence of multiple behavioral, environmental and genetic factors.

Human chemerin correlation in gingival crevicular fluid and tear fluid as markers of inflammation in chronic periodontitis and type-2 diabetes mellitus

AIM

The aim of the present study was to evaluate the levels and correlation of human chemerin in gingival crevicular fluid (GCF) and tear fluid in chronic periodontitis (CP) subjects with and without type-2 diabetes mellitus (DM).

MATERIALS AND METHODS

A total of 40 subjects were divided into three groups: group 1 had 10 periodontally healthy subjects; group 2 consisted of 15 CP subjects and group 3 had 15 type-2 DM subjects with CP. The GCF and tear fluid levels of human chemerin were quantified using enzyme linked immunosorbent assay (ELISA). Systemic parameters such as body mass index, glycated hemoglobin levels and fasting plasma glucose levels were evaluated. The clinical outcomes evaluated were gingival index (GI), probing depth (PD), and clinical attachment level (CAL), and the correlations of the two inflammatory mediators with clinical parameters were evaluated.

RESULTS

Human chemerin levels increased from group 1 to group 2 to group 3. The GCF and tear-fluid values of the inflammatory mediators correlated positively with each other and with the evaluated periodontal parameters (P < 0.05).

CONCLUSION

Human chemerin can be considered as possible GCF and tear-fluid markers of inflammatory activity in CP and DM.

Periodontal progression based on radiographic records: An observational study in chronic and aggressive periodontitis

OBJECTIVES

The current classification assumes that aggressive periodontitis (AgP) has a faster rate of progression than chronic periodontitis (CP). However, this has not been clearly proven and difficulties exist in establishing progression. This study aimed to assess the feasibility of retrospectively utilising previous records for clinical diagnosis of periodontal diseases and to assess if two different patterns of disease progression exist between AgP and CP.

MATERIALS AND METHODS

Previous radiographic records of a cohort of 235 patients clinically diagnosed with AgP or CP were requested from the referring general dental practitioners (GDPs). Comparable radiographic records were analysed in order to assess progression patterns and associate these with clinical diagnosis, by multilevel analysis.

RESULTS

43 patients out of the initial 235 had comparable radiographs retrieved from the GDPs. 858 sites were followed for an average 6.6 years. Radiographically, AgP showed a faster linear pattern of progression than CP (0.31mm/year vs. 0.20mm/year, p<0.001).

CONCLUSION

This study provides evidence for a faster disease progression in untreated AgP compared to CP as assessed by radiographic bone levels. Furthermore, it shows that retrievability of previous radiographs from GDPs is unpredictable and GDPs should be encouraged to send them along with their referral.

CLINICAL SIGNIFICANCE

The importance of differentially diagnosing AgP and CP might be useful in establishing a clinically relevant definition for periodontal disease progression and may have an impact on the clinical management of aggressive periodontitis, since our findings show that there is continuous destruction in patients with aggressive periodontitis if left untreated.

A 4-year prospective study of the progression of periodontal disease in a rural Chinese population

OBJECTIVES

The natural progression of periodontitis in the Chinese population is not well researched. We investigated the progression of periodontal disease over 4 years in 15-44-year-old Chinese villagers with no access to regular dental care.

METHODS

In 1992, 486 villagers were enrolled, and in 1996, 413 villagers were re-examined. Probing depth (PD) and clinical attachment level (CAL) were examined at six sites per tooth. Sites with ΔCAL ≥3 mm were defined as active sites. Cross-sectional and longitudinal analyses were performed using means and percentile plots.

RESULTS

The mean CAL increased by 0.26 mm over 4 years. The incidence of periodontitis (at least one site with CAL ≥3 mm) was 8%. The incidence of periodontitis among those with no periodontal disease at baseline was 44.9%. Seventy-eight percent of the subjects had at least one active site. In the 15-24-year group, 244 of 401 active sites had gingival recession, while only 51 active sites had both gingival recession and deeper pockets. In the 25-34-year and 35-44-year groups, almost one-third of the active sites (329/1087) and more than one-third of the active sites (580/1312) respectively had a combination of gingival recession and deeper pockets.

CONCLUSIONS

In this study, we demonstrated that in Chinese population without regular dental care, both the initiation of periodontitis and progression of previously existed periodontitis contributed to the natural progression of periodontitis and periodontal pocketing played a greater role with age increasing.

CLINICAL SIGNIFICANCE

This rare study reports the natural progression of periodontal disease in a group of Chinese villagers (15-44 years) with virtually no access to regular dental care.