Pathogenic factors of maxillary sinus mucosal thickening observed by cone-beam computed tomography (CBCT)

OBJECTIVE

To explore the pathogenic factors associated with maxillary sinus mucosal thickening with Cone-beam computed Tomography (CBCT).

METHODS

From 2016 through 2020, 93 patients with periapical periodontitis or periodontitis in the maxillary posterior dental region were selected.

RESULTS

The preoperative thickness of the periodontitis group was significantly higher than that of the periapical periodontitis group (P < 0.05). The difference achieves statistical significance for the comparison of the thickness change with various severity of inflammation (F = 54.824, P = 0.000), the change with time (F = 312.741, P = 0.000). and the change with the interaction severity of inflammation and time（F = 86.132, P = 0.000).

CONCLUSIONS

Patients with maxillary sinus mucosa thickening caused by periodontitis and periapical periodontitis should be extracted their infectious teeth and get thoroughly debridement. Maxillary sinus augmentation can perform favorable efforts 3-6 months after extracting teeth.

The Effect of Lasers on the Healing of Periapical Lesion: A Systematic Review

Introduction: Endodontic treatment of teeth with periapical lesions presents more clinical difficulty. Various lasers in several methods are used in endodontics, and most of them are utilized as an adjunctive protocol in order to reduce the bacterial load of the root canal system. Improved disinfection plays a crucial role in enhanced and accelerated healing of periapical lesions. This review aims to summarize studies assessing the effect of lasers on periapical lesion healing. Methods: PubMed/MEDLINE, Scopus, Embase, and Web of Science (ISI) online databases were searched, with no publication year or status restriction, for relevant articles on April 2023. Clinical studies evaluating the effect of laser application on the periapical lesion of patients using radiographic assessment were considered eligible for inclusion. Results: Eight studies were included after carefully screening the obtained articles, first by their title and abstract and then by their full texts. Diode (4), Er, Cr: YSGG (3), and Nd: YAG (1) lasers were used with output powers that varied from 0.75 to 2 watts. Photodynamic therapy was employed in two studies, and in other studies, the root canal system was directly irradiated. Irradiation of the root canal system was adjunctive to standard preparation in all studies. The healing of the teeth treated with lasers was not inferior to those conventionally treated. In all of the included studies, laser application outperformed the standard cleaning and shaping protocol; however, this improved or faster healing was not statistically significant in most studies. Conclusion: Lasers might expedite and improve the healing process of periapical lesions. Since lasers enhance the quality of cleaning of the root canal system, it is hard to point out the exact mechanism of it. Further investigations are needed to realize the effectiveness of this treatment modality and to discover the underlying biological concepts.

Outcome of root canal retreatment filled with gutta-percha techniques: A systematic review and meta-analysis

OBJECTIVE

The present systematic review and meta-analysis aimed to evaluate the success rate of root canal retreatment filled with gutta-percha and the variables related to retreatment success.

DATA

The PRISMA guidelines were followed for the present review. The study protocol was registered in the International Prospective Database of Systematic Reviews (PROSPERO CRD42021283134). Risk assessment was performed using the Newcastle-Ottawa scale. Funnel plots were used to detect publication bias and asymmetry was assessed using Egger's tests.

SOURCES

PubMed, Scopus, ScienceDirect, Cochrane, and additional sources were searched.

STUDY SELECTION

Studies published until 10 December 2022. Clinical studies evaluating the success of root canal retreatment filled with gutta-percha with at least a 1-year follow-up were selected.

RESULTS

Ten studies and one unpublished study fulfilled the inclusion criteria for quantitative analysis. The success rate of non-surgical root canal retreatment was 71% (95% CI: 66%-76%) with strict criteria and 87% (79% - 93%) with loose criteria for 1-3 years of follow-up, and 77% (66% - 86%) with strict criteria for a 4-5 years of follow-up. Endodontically retreated teeth with periapical lesions had a lower success rate under strict criteria. The tooth type, dental arch, initial periapical index (PAI) score, and the number of visits also affected the treatment success rate under strict criteria. For the loose criteria, teeth with larger periapical lesions and higher initial PAI scores had a lower success rate.

CONCLUSIONS

According to the present systematic review and meta-analysis, non-surgical root canal retreatment results in favourable outcomes. The presence of a periapical radiolucency, periapical lesions >5mm, a higher initial PAI score, multiple-visit retreatments, and mandibular and molar teeth resulted in a lower success rate.

CLINICAL SIGNIFICANCE

Non-surgical root canal retreatment filled with gutta-percha techniques is a relatively predictable procedure with a high success rate. Several variables can affect retreatment success, mainly the presence and size of a periapical lesion and the type of tooth.

Immediate implant placement for chronic peri-apical periodontitis in the molar region: a randomised controlled trial

The aim of this study was to evaluate the feasibility of immediate implantation for chronic peri-apical periodontitis in the molar region. Seventy-four molars were selected and allocated randomly to two groups. The experimental group (n = 38) received immediate implantation by flap surgery and the control group (n = 36) received delayed implantation. CBCT was performed immediately after surgery (T1) and 12 months after the permanent repair (T3). The implant survival rate at T3 was 100% in both groups. There was no significant difference in buccal or lingual vertical marginal bone loss between the groups (P = 0.515, P = 0.736). However, the buccal horizontal margin bone loss was significantly greater in the experimental group: 0.98 ± 0.34 mm vs 0.77 ± 0.27 mm in the control group (P = 0.003). In the experimental group, the highest point of buccal and lingual implant-bone contact increased at T3. The buccal and lingual jump gap widths were 3.21 ± 1.10 mm and 2.92 ± 1.01 mm at T1, and CBCT showed no jump gap around the implants at T3. The clinical outcomes showed immediate implantation to be feasible for chronic peri-apical periodontitis in the molar region.

Platelet rich fibrin and MTA in the treatment of teeth with open apices

BACKGROUND

The present study aimed to evaluate the effectiveness of using platelet-rich fibrin (PRF) as the apical matrix for the placement of MTA in nonsurgical endodontic therapy for teeth with periapical lesions and open apices.

METHODS

Twelve teeth from eleven patients with periapical periodontitis and open apices were enrolled in the study. Nonsurgical endodontic therapy was performed with the PRF used as an apical barrier and the MTA manipulated as an apical plug for further thermoplasticized gutta percha in the remaining part of the root canal. Clinical signs and periapical digital radiographs were recorded and analyzed to evaluate the curing progress after periodical follow-ups of 1, 3, and 6 months. The horizontal dimension of the periapical lesion was determined, and the changes in the dimensions were recorded each time. The Friedman test was used for statistical analysis, with P < .05 serving as the threshold for determining statistical significance.

RESULTS

All patients had no clinical symptoms after the first month of treatment, with a significant reduction in the periapical lesion after periodical appointments.

CONCLUSIONS

PRF is an effective barrier when combined with MTA for the treatment of teeth with periapical periodontitis and open apices.

The association of endodontic prognostic factors with the presence of periapical lesion, its volume, and bone characteristics in endodontically treated molars: a cross-sectional study

BACKGROUND

This study intended to evaluate the association between several endodontic prognostic factors with the presence of periapical lesions (PLs), their volume, and bone characteristics including cortical bone destruction (CBD) and buccal plate bone height (BPBH) in root-filled molar teeth using cone-beam computed tomography.

METHODS

A collection of 143 scans of endodontically treated maxillary/mandibular first or second molars recorded over 8 years, were obtained from a specialized radiology center. Data on prognostic factors including tooth number, gender, jaw type, the status and number of missed canals, obturation length, restoration type, presence of a separated instrument, presence of a post or screw in the canals, and presence of perforation were collected. The assessed outcomes included PL presence, PL volume, CBD, and BPBH. The association between prognostic factors and outcomes was evaluated using multiple logistic regression models with adjusted covariates and multifactorial ANOVA at a significance level of 0.05.

RESULTS

A total of 282 molars from 82 women and 50 men with a mean age of 40.6 ± 12.27 were included. Among those, 139 teeth presented PL with a mean volume of 18.68 mm3. CBD was prevalent in 137 teeth and the mean BPBH appeared to be 9.45 mm. The presence of a missed canal (OR = 10.022, P < .05), underfilled canal (OR = 3.725, P < .05), overfilled canal (OR = 15.859, P = .018), and perforation (OR = 15.261, P = .013) was significantly associated with PLs. None of the prognostic factors could considerably contribute to the CBD (P > .05). The presence of a missed canal was positively associated with the PL volume (P < .05). Similarly, missed canals (P < .05), perforation (P < .05), and separated instruments (P = .004) were associated with a significantly reduced BPBH.

CONCLUSIONS

Overfillings, perforations, missed canals, and underfillings were identified as remarkable predictors of PL, arranged in descending order of their respective impact. The only factor capable of significantly increasing the PL volume was the missed canal. In brief, obturation length errors, perforations, missed canals, and separated instruments were robustly correlated with endodontic failure, which highlights the importance of mitigating the potential for errors by following the fundamentals of endodontics.

The effect of periapical bone defects on stress distribution in teeth with periapical periodontitis: a finite element analysis

BACKGROUND

Apical periodontitis directly affects the stress state of the affected tooth owing to the destruction of the periapical bone. Understanding the mechanical of periapical bone defects/tooth is clinically meaningful. In this study, we evaluate the effect of periapical bone defects on the stress distribution in teeth with periapical periodontitis using finite element analysis.

METHODS

Finite element models of normal mandibular second premolars and those with periapical bone defects (spherical defects with diameters of 5, 10, 15, and 20 mm) were created using a digital model design software. The edges of the mandible were fixed and the masticatory cycle was simplified as oblique loading (a 400 N force loaded obliquely at 45° to the long axis of the tooth body) to simulate the tooth stress state in occlusion and analyze the von Mises stress distribution and tooth displacement distribution in each model.

RESULTS

Overall analysis of the models: Compared to that in the normal model, the maximum von Mises stresses in all the different periapical bone defect size models were slightly lower. In contrast, the maximum tooth displacement in the periapical bone defect model increased as the size of the periapical bone defect increased (2.11-120.1% of increase). Internal analysis of tooth: As the size of the periapical bone defect increased, the maximum von Mises stress in the coronal cervix of the tooth gradually increased (2.23-37.22% of increase). while the von Mises stress in the root apical region of the tooth showed a decreasing trend (41.48-99.70% of decrease). The maximum tooth displacement in all parts of the tooth showed an increasing trend as the size of the periapical bone defect increased.

CONCLUSIONS

The presence of periapical bone defects was found to significantly affect the biomechanical response of the tooth, the effects of which became more pronounced as the size of the bone defect increased.

The effect of root canal treatment and post-crown restorations on stress distribution in teeth with periapical periodontitis: a finite element analysis

AIM

To evaluate the effects of root canal treatment (RCT) and post-crown restoration on stress distribution in teeth with periapical bone defects using finite element analysis.

METHODOLOGY

Finite element models of mandibular second premolars and those with periapical bone defects (spherical defects with diameters of 5, 10, 15, and 20 mm) were created using digital model design software. The corresponding RCT and post-crown restoration models were constructed based on the different sizes of periapical bone defect models. The von Mises stress and tooth displacement distributions were comprehensively analyzed in each model.

RESULTS

Overall analysis of the models: RCT significantly increased the maximum von Mises stresses in teeth with periapical bone defects, while post-crown restoration greatly reduced the maximum von Mises stresses. RCT and post-crown restoration slightly reduced tooth displacement in the affected tooth. Internal analysis of tooth: RCT dramatically increased the maximum von Mises stress in all regions of the tooth, with the most pronounced increase in the coronal surface region. The post-crown restoration balances the internal stresses of the tooth and is most effective in periapical bone defect - 20-mm model. RCT and post-crown restoration slightly reduced the tooth displacement in all regions of the affected tooth.

CONCLUSIONS

Root canal treatment seemed not to improve the biomechanical state of teeth with periapical bone defects. In contrast, post-crown restoration might effectively balance the stress concentrations caused by periapical bone defects, particularly extensive ones.

Clinical efficacy of endodontic protocols on reducing cultivable bacteria and endotoxin in infected root canal in patients submitted to head and neck radiotherapy: a randomised clinical trial

OBJECTIVES

Assess the efficacy of biomechanical preparation using a reciprocating system followed by final irrigation protocols, then intracanal medication, on reducing endotoxins and cultivable bacteria of infected teeth in irradiated patients.

MATERIALS AND METHODS

Twenty-two infected single-rooted canals in patients submitted to head and neck radiotherapy were prepared by reciprocating motion and 2.5% NaOCl. Patients were randomly divided into two groups of 11 patients before the final irrigation protocol: apical positive pressure (APP) or passive ultrasonic activation (PUA). Both groups were treated in two sessions, using Ca(OH)2 as intracanal medication for 14 days. Root canal content sampling was performed after canal access (S1), after biomechanical preparation plus the irrigation protocol (S2), and after intracanal medication (S3). Chromogenic limulus amoebocyte lysate assay measured endotoxin levels (EU/mL), and bacterial load was determined by culture techniques (CFU/mL).

RESULTS

Treatment protocols reduced bacterial counts after S2 in both groups (p = 0.01). S3 differed from S1 (p = 0.01), but not from S2 (p = 0.4). Endotoxin levels were reduced in both groups after S2 (P = 0.03) and were lower in S3 than in S2, with significant differences in the APP group (p = 0.03).

CONCLUSIONS

Biomechanical preparation using a reciprocating system and 2.5% NaOCl in irradiated teeth, followed by the irrigation protocol (APP or PUA), demonstrated efficacy in reducing endodontic contaminants. Ca(OH)2 as intracanal medication should be performed in irradiated patients with infected root canals.

CLINICAL RELEVANCE

This clinical study demonstrated that endodontic treatment in irradiated patients is efficacious at reducing bacterial load and endotoxin levels.

Effects of adjacent periodontitis on osseointegrated dental implants

PURPOSE

This study aimed to investigate whether new-onset periodontitis or apical periodontitis in the adjacent teeth affects osseointegrated dental implants in a beagle dog model.

METHODS

One control group and 2 experimental groups (periodontitis and apical periodontitis groups) were defined based on the presence of experimental periodontitis or apical periodontitis, with 1 beagle dog randomly assigned to each group. The mandibular second and fourth premolars on both sides of the 3 beagles were extracted. Eight weeks after extraction, 4 bone-level implant fixtures, 2 on both sides of each mandible, were placed in each beagle. Six weeks after implant surgery, healing abutments were connected. After sufficient osseointegration, plaque control was performed in the control group, while periodontitis and apical periodontitis were induced in the experimental groups. The beagles were euthanized for histological analyses 20 weeks after induction of experimental periodontitis. Statistical analyses were performed using the Kruskal-Wallis test with the Bonferroni correction to compare the 3 groups.

RESULTS

The implants in the control and apical periodontitis groups were well-maintained, while those in the periodontitis group showed clinical signs of inflammation with bone resorption. The bone-to-implant contact (BIC) and bone area values in the periodontitis group were lower than those in the other groups. The distance between the implant shoulder and the first BIC was significantly greater in the periodontitis group than in the control group (P<0.05).

CONCLUSIONS

The presence of periodontitis in adjacent teeth can pose a risk to dental implants, potentially resulting in peri-implantitis. However, this was not observed for apical periodontitis. Within the limitations of this study, periodontal care is necessary to reduce the impact of periodontitis in adjacent teeth on osseointegrated implants.

Effect of endodontic treatment on endothelial dysfunction and subclinical atherosclerosis-a prospective intervention study

OBJECTIVE

The objective of this study is to investigate the effect of endodontic treatment on flow-mediated dilatation (FMD) and carotid intima-media thickness (c-IMT) in patients with apical periodontitis (AP).

MATERIAL AND METHOD

The study includes 32 young men having AP with a mean age of 25.78 years free from cardiovascular disease (CVD) and its risk factors, including periodontitis. All subjects underwent complete physical and dental examination, echocardiography, and ultrasound assessment of FMD on the brachial artery and c-IMT on the carotid artery at baseline and 12 months after the endodontic treatment. Data were analyzed using paired Student's t-test and Pearson's correlation coefficient (r) test using SPSS 26 version.

RESULTS

Endodontic treatment leads to the improvement of FMD significantly from a pooled baseline value of 4.84 ± 1.55% to 7.68 ± 2.08% (p < 0.05). The study also depicts a statistically significant difference between c-IMT (mean = 0.62 ± 0.11 mm) before treatment as compared to 12 months after treatment (mean = 0.59 ± 0.11 mm) (p < 0.05).

CONCLUSION

Endodontic treatment leads to improved FMD and decreased c-IMT suggesting that treating AP can be help revert the early stages of CVD.

CLINICAL RELEVANCE

AP could be a potential etiological factor of future CVD and should be treated as soon as diagnosed.

Radiographic patterns of periosteal bone reactions associated with endodontic lesions

Objectives

The formation of new bone by periosteum due to an insult is called periosteal bone reaction (PBR). This study assessed the cone beam computed tomography (CBCT) patterns of periosteal bone reactions associated with periapical inflammatory lesion (apical periodontitis/periapical rarefying osteitis).

Materials and Methods

Twenty-two small field of view CBCT images of patients with PBR were selected from a database of a private practice limited to endodontics. The volume of the periapical inflammatory lesion, the presence of cortical fenestration, the distance of the root apices to the affected cortex, and the location, pattern, and longest diameter of the periosteal reaction were recorded. Statistical analysis was performed using Wilcoxon Ranksum, Fischer's exact, Spearman Correlation Coefficient, and paired t-test.

Results

In all cases, periosteal bone reaction manifested as either parallel (90.9%) or irregular (9.1%). No correlation was found between periapical inflammatory lesion volume and the periosteal reaction's longest diameter (p > 0.05). Cortical fenestration was noted in 72.7% of the cases. In addition, the findings showed that periosteal reactions were located mostly on the buccal and were present 53.8% and 100% of the time in the mandible and maxilla, respectively.

Conclusions

The periosteal reactions of endodontic origin had a nonaggressive form (i.e., parallel or irregular), and none of the lesions resulted in a periosteal reaction with an ominous Codman's triangle or spicule pattern.

Evaluating the efficacy of endodontic microsurgery for teeth with an undeveloped root apex and periapical periodontitis after nonsurgical treatment failure

AIM

To determine the efficacy of endodontic microsurgery for teeth with an undeveloped root apex and periapical periodontitis caused by an abnormal central cusp fracture after failed nonsurgical treatment.

METHODOLOGY

Eighty teeth in 78 patients were subjected to endodontic microsurgery. All patients were clinically and radiologically examined 1 year postoperatively. The data were statistically analyzed using SPSS 27.0 software.

RESULTS

Of the 80 teeth in 78 patients, periapical lesions had disappeared in 77 teeth at 1-year postoperative follow-up, with a success rate of approximately 96.3% (77/80). The efficacy of endodontic microsurgery was not affected by sex, age, extent of periapical lesions, and presence of the sinus tract. Between-group differences were not statistically significant (P > 0.05).

CONCLUSIONS

Endodontic microsurgery can be an effective alternative treatment option for teeth with an undeveloped root apex and periapical periodontitis caused by an abnormal central cusp fracture after nonsurgical treatment failure.

Prevalence and morphological analysis of dens invaginatus in anterior teeth using cone beam computed tomography: A systematic review and meta-analysis

OBJECTIVES

To evaluate the prevalence and morphological characteristics of DI using CBCT.

METHODS

A literature search was performed in PubMed, Embase, Scopus, and Web of Science. Inclusion criteria were randomized clinical trials, cross-sectional studies, and prospective and retrospective cohort studies evaluating the morphological characteristics of DI in anterior teeth using CBCT. Three reviewer authors independently screened the studies, applied the eligibility criteria, assessed the risk of bias, and extracted until September (2022). The risk of bias was evaluated using the Joanna Briggs Institute criteria. Meta-analyses of proportions were used for estimate the prevalence DI according to factors at participant and tooth levels.

RESULTS

Six studies were included in the meta-analysis. Among 7373 individuals, a prevalence of 7.45 % of DI was observed (n = 258; τ2 = 0.0096; CI of 4.51-11.3; p < 0.05), with no significant influence of sex. Regarding laterality, unilateral DI showed higher mean prevalence (4.30 %; CI of 2.03-7.33). Among the 382 anterior teeth with DI (0.72 %), the most affected tooth was the upper lateral incisor (5.12 %; n = 329; CI of 2.35-8.86; p < 0.001), type I was the most prevalent (0.59 %; CI of 0.24-1.08) and the presence of open apex and periradicular pathology ranged from 4.3 % to 22.72 % and 3.5-77.92 %, respectively.

CONCLUSIONS

The prevalence of individuals with dens invaginatus was 7.45 %, the most affect tooth was the upper lateral incisor with a prevalence of 5.12 % unilaterally and type I was the most prevalent morphology.

Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations: a systematic review and meta-analysis

BACKGROUND

Restoring vital teeth with indirect restorations may threaten dental pulp integrity. However, the incidence of and influential factors on pulp necrosis and periapical pathosis in such teeth are still unknown. Therefore, this systematic review and meta-analysis aimed to investigate the incidence of and influential factors on pulp necrosis and periapical pathosis of vital teeth following indirect restorations.

METHODS

The search was conducted in five databases, using MEDLINE via PubMed, Web of Science, EMBASE, CINAHL, and Cochrane Library. Eligible clinical trials and cohort studies were included. The risk of bias was assessed using Joanna Briggs Institute's critical appraisal tool and Newcastle-Ottawa Scale. The overall incidences of pulp necrosis and periapical pathosis following indirect restorations were calculated using a random effects model. Subgroup meta-analyses were also performed to determine the potential influencing factors for pulp necrosis and periapical pathosis. The certainty of the evidence was assessed using the GRADE tool.

RESULTS

A total of 5,814 studies were identified, of which 37 were included in the meta-analysis. The overall incidences of pulp necrosis and periapical pathosis following indirect restorations were determined to be 5.02% and 3.63%, respectively. All studies were assessed as having a moderate-low risk of bias. The incidence of pulp necrosis following indirect restorations increased when the pulp status was objectively assessed (thermal/electrical testing). The presence of pre-operative caries or restorations, treatment of anterior teeth, temporization for more than two weeks, and cementation with eugenol-free temporary cement, all increased this incidence. Final impression with polyether and permanent cementation with glass ionomer cement both increased the incidence of pulp necrosis. Longer follow-up periods (> 10 years) and treatment provided by undergraduate students or general practitioners were also factors that increased this incidence. On the other hand, the incidence of periapical pathosis increased when teeth were restored with fixed partial dentures, the bone level was < 35%, and the follow-up was > 10 years. The certainty of the evidence overall was assessed as low.

CONCLUSIONS

Although the incidences of pulp necrosis and periapical pathosis following indirect restorations remain low, many factors affect these incidences that should thus be considered when planning indirect restorations on vital teeth.

DATABASE REGISTRATION

PROSPERO (CRD42020218378).

Three-dimensional cellular visualization in mouse apical periodontitis using combined whole-mount staining and optical tissue clearing

Apical periodontitis is an inflammatory disease involving lesions located within the jawbone. Histological evaluations generally require decalcification and sectioning, which has limited our understanding of the three-dimensional (3D) organization and spatial distribution of different immune cell types in these lesions. A recently developed technique combining tissue clearing and whole-mount immunofluorescent labeling allows us to acquire such information from the deep tissue without sectioning. However, whole-mount immunofluorescent labeling in the jawbone requires further development. Here we provide a straightforward and efficient protocol to achieve 3D immunofluorescent imaging of murine periapical lesions.

Adjuvant therapy with a 980-nm diode laser in root canal retreatment: randomized clinical trial with 1-year follow-up

The purpose of this study is to assess the laser effect in root canal disinfection and periapical healing of endodontically treated teeth from patients with asymptomatic apical periodontitis. This study was performed as a randomized clinical trial. Thirty patients were selected according to the inclusion/exclusion criteria. Fifteen patients received the root canal retreatment (RCR) combined with 980-nm diode laser irradiation (LI). The canals were irrigated with saline solution and gently dried with paper points, keeping the dentin partially moist. The irradiation was performed using a 320-µm-diameter fiber in helicoidal movements (pulsed mode, power output of 1.5 W, 100 Hz for 20 s). The other 15 patients received the RCR with placebo irradiation (PI). Microbiological samples were taken in three periods: S1, after the filling material removal (baseline); S2, after laser or placebo irradiation (LI or PI); and S3, after the RCR followed by laser or placebo. The samples were submitted to the total microbial and E. faecalis counting. The periapical radiographic healing was analyzed after 3, 6, 9, and 12 months. Microbiological data (CFU/mg) were analyzed by ANOVA and Tukey's test (P < 0.05), and the repair by Mann-Whitney test (P < 0.05). In S2, the laser provided 42.44% microbial reduction and 53.14% of E. faecalis, different from the placebo that had no reduction, and 4.85% for Enterococcus (P < 0.05). In S3, the bacterial counts decreased without differences between groups. No differences in healing were found at 3 months. However, diode laser facilitated the repair from 3- to 12-month follow-up (P < 0.05) and had 45% more healed cases than placebo. Diode laser provided an antimicrobial effect before the biomechanical preparation but was not synergistic in RCR. It improved the periapical healing during follow-up.

A prospective clinical study

BACKGROUND

The study aimed at determining antibacterial efficiency of adjuvant photodynamic therapy (PDT) and high-power diode laser (DL) in the treatment of chronic periapical periodontitis (CPP) in young permanent teeth.

METHODS

Forty-four young permanent teeth with CPP were randomly divided into three groups (PDT, DL and control). Each tooth underwent standard chemo-mechanical treatment, while within tested groups was additionally treated by PDT or DL. Bacterial identification and quantification were provided by MALDI-TOF spectrometry and plate counting assay, performed after accessing the canal, following chemo-mechanical preparation, and after PDT or DL procedure where applicable.

RESULTS

Thirty-nine young permanent teeth with CCP (patients age 9.77 ± 1.43) completed the study. Before the treatments, 202 isolates belonging to 13 genera/species, including Streptococcus (36), Actinomyces (34), Peptostreptococcus micros (27), Veillonella (25) and Enterococcus faecalis (22), were recovered. Chemo-mechanical treatment reduced CFU count in the all three groups (p < 0.001), but complete eradication was not observed for any of isolated species. Adjuvant PDT and DL completely eradicated isolates of 8 and 6 bacterial genera/species, resulting in complete bacterial elimination from 53.8% and 30.8% of root canals, respectively. In the rest canals, total Δlog CFUs were 4.71 and 4.58.

CONCLUSION

The results indicated that both PDT and DL could be performed as adjuvants to standard endodontic treatment of the young permanent teeth with CPP.

3D printed scaffold for repairing bone defects in apical periodontitis

Objectives

To investigate the feasibility of the 3D printed scaffold for periapical bone defects.

Methods

In this study, antimicrobial peptide KSL-W-loaded PLGA sustainable-release microspheres (KSL-W@PLGA) were firstly prepared followed by assessing the drug release behavior and bacteriostatic ability against Enterococcus faecalis and Porphyromonas gingivalis. After that, we demonstrated that KSL-W@PLGA/collagen (COL)/silk fibroin (SF)/nano-hydroxyapatite (nHA) (COL/SF/nHA) scaffold via 3D-printing technique exhibited significantly good biocompatibility and osteoconductive property. The scaffold was characterized as to pore size, porosity, water absorption expansion rate and mechanical properties. Moreover, MC3T3-E1 cells were seeded into sterile scaffold materials and investigated by CCK-8, SEM and HE staining. In the animal experiment section, we constructed bone defect models of the mandible and evaluated its effect on bone formation. The Japanese white rabbits were killed at 1 and 2 months after surgery, the cone beam computerized tomography (CBCT) and micro-CT scanning, as well as HE and Masson staining analysis were performed on the samples of the operation area, respectively. Data analysis was done using ANOVA and LSD tests. (α = 0.05).

Results

We observed that the KSL-W@PLGA sustainable-release microspheres prepared in the experiment were uniform in morphology and could gradually release the antimicrobial peptide (KSL-W), which had a long-term antibacterial effect for at least up to 10 days. HE staining and SEM showed that the scaffold had good biocompatibility, which was conducive to the adhesion and proliferation of MC3T3-E1 cells. The porosity and water absorption of the scaffold were (81.96 ± 1.83)% and (458.29 ± 29.79)%, respectively. Histological and radiographic studies showed that the bone healing efficacy of the scaffold was satisfactory.

Conclusions

The KSL-W@PLGA/COL/SF/nHA scaffold possessed good biocompatibility and bone repairing ability, and had potential applications in repairing infected bone defects.

Clinical significance The 3D printed scaffold not only has an antibacterial effect, but can also promote bone tissue formation, which provides an alternative therapy option in apical periodontitis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02362-4.

Effect of Enterococcus faecalis OG1RF on human calvarial osteoblast apoptosis

Background

Enterococcus faecalis is a dominant pathogen in the root canals of teeth with persistent apical periodontitis (PAP), and osteoblast apoptosis contributes to imbalanced bone remodelling in PAP. Here, we investigated the effect of E. faecalis OG1RF on apoptosis in primary human calvarial osteoblasts. Specifically, the expression of apoptosis-related genes and the role of anti-apoptotic and pro-apoptotic members of the BCL-2 family were examined.

Methods

Primary human calvarial osteoblasts were incubated with E. faecalis OG1RF at multiplicities of infection corresponding to infection time points. Flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay, caspase-3/-8/-9 activity assay, polymerase chain reaction (PCR) array, and quantitative real-time PCR were used to assess osteoblast apoptosis.

Results

E. faecalis infection increased the number of early- and late-phase apoptotic cells and TUNEL-positive cells, decreased the mitochondrial membrane potential (ΔΨm), and activated the caspase-3/-8/-9 pathway. Moreover, of all 84 apoptosis-related genes in the PCR array, the expression of 16 genes was upregulated and that of four genes was downregulated in the infected osteoblasts. Notably, the mRNA expression of anti-apoptotic BCL2 was downregulated, whereas that of the pro-apoptotic BCL2L11, HRK, BIK, BMF, NOXA, and BECN1 and anti-apoptotic BCL2A1 was upregulated.

Conclusions

E. faecalis OG1RF infection triggered apoptosis in human calvarial osteoblasts, and BCL-2 family members acted as regulators of osteoblast apoptosis. Therefore, BCL-2 family members may act as potential therapeutic targets for persistent apical periodontitis.

Role of NOD2 and hepcidin in inflammatory periapical periodontitis

The immunological response occurring during periapical inflammation includes expression of nucleotide binding oligomerization domain containing 2 and hepcidin. Nucleotide binding oligomerization domain containing 2 deficiency increases infiltration of inflammatory cells close to alveolar bone. Hepcidin has an important role in iron metabolism affecting bone metabolism.We investigated the role of nucleotide binding oligomerization domain containing 2 and hepcidin in inflammatory periapical periodontitis. Periapical periodontitis was induced in rats and confirmed by micro-computed tomography. Nucleotide binding oligomerization domain 2 and hepcidin were evaluated through immunohistochemistry. Bioinformatics analysis was undertaken usingthe Kyoto Encyclopedia of Genes and Genomes and Gene Ontology databases. Micro-computer tomography revealed alveolar bone resorption in the periapical region and furcation area of mandibular molars in rats of the periapical periodontitis group. Immunohistochemistry showed increased expressionof nucleotide binding oligomerization domain containing 2 and hepcidin around root apices in rats of the periapical periodontitis group. Bioinformatics analysis of differentially expressed genes in inflamed and non-inflamed tissues revealed enrichment in the NOD-like receptor signaling pathway. Our data suggest that nucleotide binding oligomization domain contain2 and hepcidin have important roles in periapical periodontitis severity because they can reduce alveolar bone loss.They could elicit new perspectives for development of novel strategies for periapical periodontitis treatment.

Association between periodontitis and ossification of the posterior longitudinal ligament: a case report

Introduction

Ossification of the posterior longitudinal ligament in the spinal ligament compresses the spinal cord, causing various spinal nerve diseases. The ligament tissue is an important connective tissue in the joints, teeth, and spine, which, when torn and damaged, reduces the range of movement.

Case presentation

We report the treatment of periapical periodontitis and tooth preservation in a 41-year-old Japanese woman previously diagnosed with ossification of the posterior longitudinal ligament. She presented with widespread pain from the paranasal sinuses to the head caused by the onset of periapical periodontitis of the upper front tooth.

Discussion

The patient received an oral zinc supplement, which resolved periapical periodontitis over a 2-year follow-up period.

Conclusion

The findings from this case imply that, when patients with ossification of the posterior longitudinal ligament develop periapical periodontitis, they should be tested for zinc deficiency.

Is the quality of root canal filling obtained by cone-beam computed tomography associated with periapical lesions? A systematic review and meta-analysis

AIM

To evaluate the influence of root canal filling quality on periapical lesion status using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

The bibliographic search was conducted in electronic databases of PubMed, Embase, Scopus, and Web of Science without restrictions related to the year of publication and language. Inclusion criteria were prospective or retrospective cohort studies that followed periapical pathosis for, at least, 1 year. Three reviewers independently evaluated the eligibility for inclusion, extracted data, and assessed the risk of bias. The quality of the studies was based on the Newcastle-Ottawa Scale. This meta-analysis was performed to evaluate the quality of treatment by the homogeneity and apical extension of the filling.

RESULTS

Of the 1179 studies initially recovered, six cohort studies were included, out of which four were considered with a low risk of bias. The results showed that the absence of gaps in the filling reduced the chance of unhealed periapical lesions by 2.39 times (RR = 2.39; 95% CI: 1.62-3.53; p < 0.00001; I² = 55%). An apical filling extension of 0-2 mm below the apex also contributed significantly to the absence of unhealed periapical lesions (RR = 1.49; 95% CI: 1.15-1.94; p = 0.003; I² = 2%).

CONCLUSION

The homogeneity and apical extension of the filling influenced the presence of unhealed periapical lesions in endodontically treated teeth evaluated using CBCT.

CLINICAL RELEVANCE

Apical extension of the filling ranging between 0 and 2 mm short of the apical foramen and the homogeneity of the filling without gaps are directly related to the success rate of root canal treatment.

Morphological changes of the root apex in anterior teeth with periapical periodontitis: an in-vivo study

Introduction

The aim was to analyze the morphological changes of root apex in anterior teeth with periapical periodontitis.

Methods

32 untreated anterior teeth with periapical periodontitis were enrolled, compared with the healthy contralateral teeth. Two-dimensional measurement of Cone-beam computed tomography was used to determine the location and measure diameter of the apical constriction according to Schell’s methods. An open-source software (3D Slicer) was used to reconstruct the teeth. The apical constriction form was analysis according to Schell’s topography. The distances of apical constriction to apical foramen and anatomical apex were measured respectively.

Results

The difference value between buccolingual and mesiodistal diameter was (0.06 ± 0.09) mm and (0.04 ± 0.04) mm in periapical periodontitis and controls (p < 0.05). The mean distance between apical constriction and anatomical apex was significantly shorter in periapical periodontitis than controls, so was the mean distance of apical constriction to apical foramen. The most common form of apical constriction was flaring (65.6%) in periapical periodontitis.

Conclusions

The anterior teeth with periapical periodontitis had shorter distances of apical constriction to anatomical apex and apical foramen, bigger disparities between the diameters of buccolingual and mesiodistal, and higher proportion of flaring apical constriction.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02062-z.

Metabolome and microbiome of chronic periapical periodontitis in permanent anterior teeth: a pilot study

Background

Periapical periodontitis is a common oral inflammatory disease that affects periapical tissues and is caused by bacteria in the root canal system. The relationship among the local metabolome, the inflammatory grade, and the type and abundance of microorganisms associated with periapical periodontitis is discussed in this study.

Methods

The inflammatory grades of periapical samples from 47 patients with chronic periapical periodontitis in permanent anterior teeth were determined based on the immune cell densities in tissues subjected to haematoxylin and eosin staining. The metabolome was evaluated using ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, followed by principal component analysis and orthogonal partial least squares discriminant analysis. The microbiome was accessed using 16 S rRNA high-throughput sequencing. The differences in the metabolomes and microbiomes of the periapical periodontitis samples were assessed using Spearman’s correlation analysis.

Result

N-acetyl-D-glucosamine, L-tryptophan, L-phenylalanine, and 15 other metabolites were identified by the comparison between samples with severe inflammation and mild or moderate inflammation. Four amino acid metabolism pathways and one sugar metabolism pathway were associated with the inflammatory grade of periapical periodontitis. The abundance of Actinomycetes was negatively correlated with the abundance of glucosamine (GlcN), while the abundance of Tannerella was positively correlated with the abundance of L-methionine.

Conclusions

The local metabolome of periapical periodontitis is correlated with the inflammatory grade. The abundance of the local metabolites GlcN and L-methionine is correlated with the abundance of the major microorganisms Actinomycetes and Tannerella, respectively.

Evaluation of the effect of periapical lesions and other odontogenic conditions on maxillary sinus mucosal thickness characteristics and mucosal appearance: A CBCT study

Background. This retrospective study aimed to investigate the effect of various dental and maxillary sinus variables on maxillary sinus mucosal thickness (MT). The variables included periodontal bone loss (PBL), periapical status, dental restorations of posterior maxillary teeth, and the distance from the root apices to the sinus mucosa.

Methods. Cone-beam computed tomography (CBCT) images of the maxillary sinuses (n = 600) in 300 patients were examined. The sinus MT and the distance of the roots from maxillary sinuses were measured. Apical lesions of the roots, PBL, and situations of adjacent teeth were recorded. The relationships between these conditions and MT and characterization of MT were evaluated. The Kruskal–Wallis H test was used to compare groups due to the non-normal distribution of the data. The relationship between categorical variables was analyzed using chi-squared test.

Results. There was a significant correlation between maxillary sinus MT and periapical lesions, PBL, and restorations (P < 0.05). MT increased as the apical lesions of premolar teeth enlarged (P < 0.05, P = 0.022). MT increased in cases of mild PBL of molar teeth (P = 0.041).

Conclusion. In this retrospective study, the MT significantly increased in patients with periapical lesions, inadequate endodontic treatment, increased PBL, and inadequate dental restorations.

CALCIUM HYDROXIDE (CA[OH]2) AS AN INTRACANAL MEDICATION MAY SIGNIFICANTLY REDUCE ENDOTOXINS LEVEL FROM INFECTED TEETH

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Bedran NR, Nadelman P, Magno MB, de Almeida Neves A, Ferreira DM, Braga Pintor AV, Maia LC, Primo LG. Does Calcium Hydroxide Reduce Endotoxins in Infected Root Canals? Systematic Review and Meta-analysis. J Endod. 2020 Aug 11:S0099-2399(20)30582-3. doi:10.1016/j.joen.2020.08.002. Epub ahead of print. PMID: 32795549.

SOURCE OF FUNDING

This systematic review was supported in part by the Coordenaçao de Aperfeiçoamento de Pessoal de Nível Superior (finance code 001, 88882.424816/2019-01) and Fundaçao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (grant nos. E-26/202.334/2019, E-26/202.399/ 2017, and E-26/210.352/2019).

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis.

Localization of interleukin-6 signaling complex in epithelialized apical lesions of endodontic origin

OBJECTIVES

We aimed to determine the immunolocalization patterns of the interleukin (IL)-6 signaling complex in epithelialized and non-epithelialized apical lesions of endodontic origin (ALEOs).

MATERIALS AND METHODS

Epithelialized (n = 8) and non-epithelialized (n = 7) ALEOs were obtained from teeth with indication of extraction in patients with clinical diagnosis of apical periodontitis. All tissues were subjected to routine processing for histopathologic examination and primary antibodies for IL-6, IL-6 receptor (R), and glycoprotein (gp)-130 were used for immunohistochemistry and double immunofluorescence co-localization.

RESULTS

IL-6, IL-6R, and gp-130 were immunolocalized in endothelial cells and mononuclear leukocytes in a diffuse pattern within the connective tissue of epithelialized and non-epithelialized ALEOs. In the epithelialized lesions, two different patterns were identified: IL-6 signaling complex was localized within the proliferating epithelium in a diffuse intracellular pattern and in a cell membrane localization pattern within the mature epithelial lining, showing a decreased intensity towards the surface layers.

CONCLUSIONS

IL-6, IL-6R, and gp-130 localized to mononuclear inflammatory cells, vascular endothelial cells, and immature proliferating epithelia in a diffuse pattern and in mature lining epithelia in a localized cell membrane pattern, supporting a role for epithelial proliferation during cyst formation. Additional cell membrane co-localization of IL-6 receptor complex suggests classic signaling involvement in addition to trans-signaling.

The influence of periapical lesions on the repeatability of two electronic apex locators in vivo

OBJECTIVES

To determine the influence of periapical lesions on the repeatability of two electronic apex locators (EALs), Root ZX II, and RomiApex A-15, in maxillary anterior teeth, in vivo.

MATERIALS AND METHODS

After approval by the local ethics committee, 43 maxillary anterior teeth scheduled for root canal therapy were assigned to two groups. The periapical lesion (PAL) group included 21 teeth with necrotic pulps and radiographically visible periapical lesion, and the normal periapex (NPA) group consisted of 22 teeth with vital pulps and no periapical lesion. In each canal, Root ZX II and RomiApex A-15 were used to determine working length defined as the "zero" reading on the display. Two consecutive measurements were performed with each EAL on each tooth and a second operator measured the endodontic file with a digital caliper without knowledge of the EAL being used or the tooth diagnosis. The absolute value of the difference between the first and second measurement (measurement pairs) was calculated. Repeatability was evaluated by the Bland-Altman method, and an aligned ranks transformation ANOVA was conducted to compare the EALs.

RESULTS

The median absolute difference between measurement pairs was significantly lower (p < 0.001) and the limits of agreement were narrower in the NPA group. Among the EALs, median absolute differences were significantly smaller for Root ZX (p < 0.001).

CONCLUSIONS

Measurements were more repeatable when no periapical lesion was present. Root ZX showed better repeatability than RomiApex.

CLINICAL RELEVANCE

Periapical lesions seem to influence successive in vivo measurements with EALs.

Smoking May Increase the Risk of Periapical Periodontitis

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

The association between smoking and periapical periodontitis: a systematic review. Aminoshariae A, Kulild J, Gutmann J.Clin Oral Investig 2020;24(2):533-545. https://doi.org/10.1007/s00784-019-03094-6.

SOURCE OF FUNDING

None. The authors declared no conflict of interest.

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis.

High-fat diet effect on periapical lesions and hepatic enzymatic antioxidant in rats

AIMS

To evaluate the effects of a high-fat diet (HFD) on the progression of apical periodontitis (AP), local inflammation, systemic antioxidant status, and blood lipid profile in rats.

MAIN METHODS

Sixteen male Wistar rats were fed a standard diet (SD) or a HFD. At the sixth experimental week, the pulp chambers of the mandibular first molars were exposed to develop AP. A glucose tolerance test was performed the week before euthanasia. At the tenth experimental week, the animals were euthanized and the livers were collected to estimate catalase (CAT) and reduced glutathione (GSH) levels. Blood was acquired for biochemical analysis. The size of AP was estimated from radiographs and described as AP size-to-body weight ratio; inflammatory grade of AP was determined by histological analysis.

KEY FINDINGS

At the end of the experimental period, the rats fed the HFD had 30% less weight (P < 0.0001) and higher blood glucose levels after 30 min of sucrose intake (P < 0.05) than those fed the SD. Animals from the HFD group had lower levels of CAT (P < 0.01), but the same was not observed in the GSH levels. Plasma insulin and total cholesterol were not affected by the diet. The rats fed the HFD presented greater AP than those fed the SD (P < 0.05). However, the local inflammatory infiltrate was similar in both groups.

SIGNIFICANCE

The alterations promoted by the consumption of a HFD were not only observed systemically, but also locally, producing greater AP in rats than a SD.

Missed canals in endodontically treated maxillary molars of a Brazilian subpopulation: prevalence and association with periapical lesion using cone-beam computed tomography

OBJECTIVES

To evaluate the prevalence of missed canals in endodontically treated maxillary molars through cone-beam computed tomography (CBCT) images and to verify their association with the presence of periapical lesions.

MATERIAL AND METHODS

Three oral radiologists evaluated 633 maxillary molars in CBCT exams regarding number of roots, number of root canals, number of missed canals, anatomic identification of missed canals, presence of periapical lesions, and root location of the periapical lesions. Data were statistically analyzed at a 5% significance level.

RESULTS

Descriptive statistical analysis showed that among 395 first molars, 218 had at least one missed canal, and 186 (46.5%) had a missed canal and periapical lesion simultaneously. Of these, 72.4% (134) of the missed canals were only mesiobuccal 2 (MB2). Among 238 s molars evaluated, 121 presented at least one missed canal, and 104 (43.6%) had a missed canal and periapical lesion simultaneously. Of these, 81.7% (85) of the missed canals were only MB2. The chi-squared test showed an association between the presence of missed canals and periapical lesions for 1st and 2nd maxillary molars. Teeth that presented a missed canal showed an odds ratio (OR) of 2.57 (p < 0.0001) of being associated with a periapical lesion. Missed canal occurrence was positively related to the number of root canals (z = 13.06, p < 0.0001), meaning when the number of root canals is higher, there is a higher probability of missed canal occurrence. According to the model calculated prediction, for a one-unit increase in the number of canals, the probability of missed canals increases by 4.22%.

CONCLUSIONS

It was concluded that MB2 was the most frequently missed canal, associated with the presence of periapical lesions in endodontically treated maxillary molars.

CLINICAL RELEVANCE

Professionals' negligence of anatomical root variations has been contributed to the high prevalence of missed canals, leading to failures in endodontic treatment. Their association with periapical lesion occurrence emphasizes the importance of correct detection and instrumentation of these canals.

Influence of glide path kinematics during endodontic treatment on the occurrence and intensity of intraoperative and postoperative pain: a systematic review of randomized clinical trials

Background

Preliminary canal enlargement (glide path preparation) may play a significant role in the development of pain. The aim of this systematic review of randomized clinical trials was to assess the influence of glide path kinematics during endodontic treatment on the occurrence and intensity of intraoperative and postoperative pain.

Methods

A search was performed in June 2019 in six electronic databases (PubMed, Scopus, LILACS, SciELO, Embase and Web of Science) and two grey literature databases (OpenGrey and OpenThesis). The bibliographic references of the eligible articles were also hand-searched. The included clinical studies assessed the occurrence and intensity of intraoperative and/or postoperative pain after root canal preparation without glide path preparation (WGP) or with glide path preparation using manual (M-GP), continuous rotary (CR-GP), or reciprocating (R-GP) instruments. The primary outcome was the occurrence and intensity of intraoperative and postoperative pain, while analgesic consumption was the secondary outcome. The full texts of the eligible studies were analyzed by two reviewers who performed calibration exercises to verify the risk of bias and quality of the individual studies using the Joanna Briggs Institute Critical Appraisal tool.

Results

From 1283 identified articles, only six studies were included in the qualitative analysis of the results, with a total sample of 884 patients/teeth. Three studies presented a high risk of bias, while three studies presented a moderate risk. Two studies reported that CR-GP causes lower pain levels than M-GP and WGP, and three studies showed no differences between CR-GP and R-GP. Regarding analgesic consumption, two studies found no differences among glide path kinematics, and one study reported lower consumption for CR-GP than for M-GP. Because of the limited number of studies and methodological differences, no statistical analyses were performed for the glide path kinematics comparisons.

Conclusions

Compelling evidence indicating a significantly different occurrence and intensity of pain among glide path kinematics is lacking.

The systematic review protocol was registered in the PROSPERO database [CRD42020139989].

Cathepsin C promotes the progression of periapical periodontitis

Although the role of cathepsin C (Cat C) in inflammation is gradually being elucidated, its function in periapical periodontitis, which is one of the most common infectious diseases worldwide, has not been studied. This study evaluated a surgically-induced model of periapical periodontitis in cathepsin C (Cat C) knock-down (KD) mice, which was constructed with a tetracycline operator, to evaluate the role of Cat C in the pathogenesis and progression of periapical periodontitis. Our results showed, for the first time, that there was a statistically significant increase in the expression of Cat C as periapical periodontitis progressed; this increase started from 1 week after surgery and reached a peak at 3 weeks after surgery, before gradually decreasing. The volume of periapical bone resorption in Cat C KD mice was significantly smaller than that in wild-type mice at 3 and 4 weeks after surgery (P<0.05). Inflammatory cell infiltration into the apical tissues of wild-type mice was also significantly higher than that of Cat C KD mice. The expression of receptor activator of nuclear factor-κB ligand (RANKL) in wild-type mice was also higher than that in Cat C KD mice. The difference in the number of osteoclasts in the apical area between the two groups was statistically significant after 2 weeks. Correlation analysis showed that there was a significant correlation between Cat C and RANKL expression (r= 0.835). Therefore, our data indicated that Cat C promoted the apical inflammation and bone destruction in mice.

Nano-graphene oxide with antisense walR RNA inhibits the pathogenicity of Enterococcus faecalis in periapical periodontitis

Background/purpose

Enterococcus faecalis (E. faecalis) is considered a predominant pathogen for persistent periapical infections. Antisense walR (ASwalR) RNA was reported to inhibit the biofilm formation and sensitized E. faecalis to calcium hydroxide medication. The aims of this study were to investigate whether the graphene oxide (GO) nanosheets could be used to enhance antibacterial activity of ASwalR RNA for E. faecalis in periapical periodontitis.

Materials and methods

We developed a graphene-based plasmid transformation system by loading antisense walR plasmid with GO-polyethylenimine (PEI) complexes (GO-PEI-ASwalR). The particle size distributions and zeta-potential of the GO-PEI-ASwalR were evaluated. Then, ASwalR plasmids were labeled with gene encoding enhanced green fluorescent protein (ASwalR-eGFP). The transformation efficiencies and the bacterial viability of E. faecalis were evaluated by confocal laser scanning microscopy. Quantitative real-time PCR assays were used to investigate the expressions of E. faecalis virulent genes after transformed by GO-PEI-ASwalR. Also, the antibacterial properties of the GO-PEI-ASwalR were validated in the rat periapical periodontitis model.

Results

We showed that GO-PEI could efficiently deliver the ASwalR plasmid into E. faecalis cell. GO-PEI-ASwalR significantly reduced virulent-associated gene expressions. Furthermore, GO-PEI-ASwalR suppressed biofilm aggregation and improved bactericidal effects using infected canal models in vitro. In four-weeks periapical infective rat models, the GO-PEI-ASwalR strains remarkably reduced the periapical lesion size.

Conclusion

Transformation efficiency and antibacterial prosperity of ASwalR can be marked improved by GO-PEI based delivery system for E. faecalis infections.

The association between smoking and periapical periodontitis: a systematic review

OBJECTIVES

The purpose of this systematic review was to examine if, in adult patients, the absence or presence of smoking influenced the prevalence of periapical periodontitis (PP).

MATERIALS AND METHODS

Databases were searched, and original research manuscripts up to June 2019 were identified by two reviewers. The Newcastle-Ottawa Scale (NOS) was used for risk of bias. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system was used for certainty in the evidence. A meta-analysis was performed using RevMan 5 software. Risk ratio (RR) was used for the cohort studies, and odds ratio (OR) was used for the case-control studies with 95% confidence interval (CI).

RESULTS

All the studies had many covariates and confounding variables. Three longitudinal cohort articles discussed radiographic findings as they related to the prevalence of PP in root-filled teeth. The RR of smoking and the prevalence of PP was 2.11 (95% CI 0.88-5.05, p = 0.09). Nine case-control studies focused on the prevalence of PP and smoking. There was a positive association between smoking and the prevalence of PP with an OR of 2.78 and a 95% confidence interval of 2.23-3.48, with p value < 0.05. The quality of the studies was fair per NOS, and the certainty of the literature assessment was moderate per GRADE.

CONCLUSIONS

The current best available evidence suggests that smoking was associated with the prevalence of PP but more studies are needed to report this association in the longitudinal cohort studies.

CLINICAL RELEVANCE

Smoking has a positive association with the prevalence of PP.

Effects of different alcohol concentrations on the development of apical periodontitis in rats

AIM

To investigate the effect of different alcohol concentrations on the development of apical periodontitis (AP) in rats.

METHODS

Forty Wistar rats were arranged into five groups: (C) - control rats receiving sterile water as the only liquid; (G5) - animals receiving an alcohol solution at 5%, (G10) - alcohol solution at 10%, (G15) - alcohol solution at 15%, and (G20) - alcohol solution at 20%. The alcoholic solution or water was given to the groups as the sole source of hydration throughout the 30 days of the experiment. AP was induced in the mandibular molars on the first day. In the end, the animals were euthanized for histopathological and IL-1b, RANKL, OPG, and TRAP analyses. The Kruskal-Wallis test was used for nonparametric data, and ANOVA followed by the Tukey test were performed for parametric data, p < 0.05.

RESULTS

G15 and G20 had a greater chronic inflammatory infiltrate (Score 3) and AP size bigger (1.59 ± 0.41 and 1.83 ± 0.38, respectively) than the C, G5 and G10 (p < 0.05). No significant difference was found in the IL-1b analyses. The G15 and G20 showed the highest immunolabeling pattern for RANKL and the lowest for OPG. The G20 had greater TRAP cells per mm (4.70 ± 0.99) compared to the C, G5, and G10 (p < 0.05). Furthermore, G15 presented 3.92 ± 0.64 TRAP cells/mm, higher than C (p < 0.05).

CONCLUSIONS

G5 and G10 did not exert a protective or aggravating effect on the AP development. However, G15 and G20 had a significant effect on the AP severity, exacerbating the inflammation and osteoclast markers.

Evaluation of the Relationship between Type II Diabetes Mellitus and the Prevalence of Apical Periodontitis in Root-Filled Teeth Using Cone Beam Computed Tomography: An Observational Cross-Sectional Study

OBJECTIVE

This study aimed to investigate the prevalence of apical periodontitis (AP) in patients with type II diabetes mellitus (DM) with either optimal glycemic control (OGC) or poor glycemic control (PGC) compared with nondiabetics using cone beam computed tomography (CBCT).

SUBJECTS AND METHODS

The periapical status of 75 teeth with adequate root canal treatment performed at least 1 year ago that could be visualized in the field of view of CBCT images of 43 DM patients (29 females, 14 males) was compared with a control group consisting of 162 teeth of 86 nondiabetics (56 females, 30 males). In addition, the DM group was divided into subgroups according to the patients' mean glycated hemoglobin level as either having OGC or PGC. The periapical status of the teeth was evaluated using the CBCT periapical index (CBCTPAI), and AP was diagnosed as a CBCTPAI ≥1. χ2, Fisher's exact test, and independent-samples t tests were used for the statistical analysis, and p < 0.05 was considered significant.

RESULTS

Significant differences between the DM group and the control group were observed (p< 0.05) in terms of AP (the frequencies of both CBCTPAI ≥1 and CBCTPAI ≥3) and the frequency of cardiovascular disease, while there were no significant differences between the DM subgroups (p > 0.05).

CONCLUSION

The prevalence of AP and severe bone destruction in periapical tissues was significantly higher in the DM patients compared with the nondiabetic patients.

Periodontal regenerative therapy in endo-periodontal lesions: a retrospective study over 5 years

Purpose

The aim of this study was to evaluate clinical and radiographic changes and the survival rate after periodontal surgery using deproteinized bovine bone mineral (DBBM) with 10% collagen or DBBM with a collagen membrane in endo-periodontal lesions.

Methods

A total of 52 cases (41 patients) with at least 5 years of follow-up were included in this study. After scaling and root planing with or without endodontic treatment, periodontal regenerative procedures with DBBM with 10% collagen alone or DBBM with a collagen membrane were performed, yielding the DBBM + 10% collagen and DBBM + collagen membrane groups, respectively. Changes in clinical parameters including the plaque index, bleeding on probing, probing pocket depth, gingival recession, relative clinical attachment level, mobility, and radiographic bone gains were evaluated immediately before periodontal surgical procedures and at a 12-month follow-up.

Results

At the 12-month follow-up after regenerative procedures, improvements in clinical parameters and radiographic bone gains were observed in both treatment groups. The DBBM + 10% collagen group showed greater probing pocket depth reduction (4.52±1.06 mm) than the DBBM + collagen membrane group (4.04±0.82 mm). However, there were no significant differences between the groups. Additionally, the radiographic bone gain in the DBBM + 10% collagen group (5.15±1.54 mm) was comparable to that of the DBBM + collagen membrane group (5.35±1.84 mm). The 5-year survival rate of the teeth with endo-periodontal lesions after periodontal regenerative procedures was 92.31%.

Conclusions

This study showed that regenerative procedures using DBBM with 10% collagen alone improved the clinical attachment level and radiographic bone level in endo-periodontal lesions. Successful maintenance of the results after regenerative procedures in endo-periodontal lesions can be obtained by repeated oral hygiene education within strict supportive periodontal treatment.

Epithelioid cell granuloma with caseating necrosis possibly caused by periapical periodontitis: a case report

Background

Epithelioid cell granuloma with caseating necrosis is a typical pathological finding in tuberculosis. While specific inflammation, including that related to tuberculosis, can induce caseating granuloma formation, there have been very few reports on the induction of caseating granuloma by non-specific inflammation. Chronic periapical periodontitis is usually related to bacterial biofilm formation as well as fungal or viral infection in the periapical lesion. However, it is difficult to eliminate these extraradicular pathogenic microbes by normal endodontic therapy alone, and more invasive surgical removal is almost always required.

Case presentation

Here we describe the case of a 30-year-old Japanese woman who had suffered from dull pain related to periapical periodontitis for approximately 10 years. Although the causal tooth had been previously extracted at the Department of Oral Surgery of another hospital in 2015, inflammation of the surrounding tissue had not abated. She was referred to our hospital in May 2016 and underwent surgical debridement via an intra/extraoral approach under general anesthesia. A caseating granuloma accompanied by a small amount of fungi was histopathologically confirmed in the excised specimen. Her inflammation has not been exacerbated since the operation.

Conclusions

This is the first report in which non-specific inflammation is shown to induce caseating granuloma arising in the jaw. Our report also highlights the importance of sufficient root canal treatment during the first stage of the procedure.

Increased interleukin 1α and interleukin 1β expression is involved in the progression of periapical lesions in primary teeth

BACKGROUND

Interleukin 1 (IL-1) is involved in bone resorption. However, the role of IL-1 in periapical lesions characterized by periapical bone destruction in primary teeth has not yet been fully elucidated. This study aimed to detect the distribution and expression of IL-1 in periapical lesions in primary teeth and assess the relationship between the cytokines and the degree of inflammatory cell infiltration.

METHODS

A total of 106 chronic periapical lesions in primary teeth were harvested. Haematoxylin and eosin (H&E) staining was used to determine the histological type and the inflammatory cell infiltration grade (mild, moderate, and severe), and immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) were used to detect the distribution and expression of IL-1α and IL-1β.

RESULTS

Of the 106 chronic periapical lesion samples, there were 85 cases of periapical granuloma, accounting for 80.19% of the total samples, and 21 cases of radicular cysts, accounting for 19.81%; no cases of abscess were detected. Immunohistochemistry results showed that both IL-1α and IL-1β were expressed in periapical granulomas and cysts. ELISA results showed that IL-1α and IL-1β levels were higher in the periapical granuloma group than in the radicular cyst and normal control groups (P < 0.05). In the periapical granuloma group, IL-1α and IL-1β were detected at higher levels in the severe inflammatory cell infiltration subgroup than in the mild-inflammatory cell infiltration subgroup (P < 0.05), and IL-1β expression was also higher in the moderate inflammatory cell infiltration subgroup than in the mild inflammatory cell infiltration subgroup (P < 0.01). A significant positive correlation was observed between the protein expression levels of IL-1α and IL-1β and the inflammation grade in periapical granulomas from primary teeth (P < 0.05).

CONCLUSION

Expression levels of the cytokines IL-1α and IL-1β in periapical granulomas from primary teeth increased with increasing inflammatory severity and appeared to be a contributing factor to the progression of periapical lesions.

[Association of fimA genotype to kgp genotype in Porphyromonas gingivalis from infected root canals of primary apical periodontitis]

Objective: To investigate the distribution of fimA and kgp genotypes as well as the common genotype combination of Porphyromonas gingivalis (Pg) in infected root canals of primary apical periodontitis for virulent isolates screening in future. Methods: Thirty-four samples harboring Pg were selected from infected root canals of primary apical periodontitis from patients of the Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine from June 2013 to September 2015. FimA type-specific primers were used to amplify the samples, revealing the distribution of various fimA genotypes. The genotypes of kgp were obtained by using Mse Ⅰ restriction endonuclease. The prevalence of each genotype and common genotype combinations were then calculated. Pearson's chi-squared test was performed to analyze the correlation between genotype combinations and clinical symptoms and major signs of apical periodontitis. In addition, the bioflim architectures between Pg isolates with different fimA and kgp genotype combinations were observed compared using confocal laser scanning microscope. Results: Among the 34 Pg-positive samples, fimA Ⅱ was the most prevalent genotype [47% (16/34)] followed by fimA Ⅰ [26% (9/34)], while fimA Ⅴ was detected in only one sample. The prevalence of kgp Ⅰ [56% (19/34)] was slightly higher than that of kgp Ⅱ [44% (15/34)]. Both fimA Ⅱ+kgp Ⅰ and fimAⅡ+kgp Ⅱ were the most prevalent genotype combinations [24% (8/34) each]. No significant correlation was found between specific genotype combination and such major clinical manifestations as gingival swelling and sinus tract of dental origin (P>0.05). Three Pg isolates with different genotype combinations were acquired. Isolate A (fimAⅠ+kgpⅠ) formed densest biofilm, while the biofilm of isolate C (fimAⅤ+kgp Ⅰ) was much looser. The biofilm feature of isolate B (fimAⅢ+kgp Ⅱ) fell in between A and C. Conclusions: Pg with fimA Ⅱ was most frequently detected in infected root canals of primary apical periodontitis. The prevalence of Pg with kgp Ⅰ was slightly higher than that with kgp Ⅱ, and fimAⅡ+kgp Ⅰ as well as fimA Ⅱ+kgp Ⅱ were the commonest genotype combinations. According to the comparison of Pg biofilms formed by clinical isolates, it might be possible that different genotype combinations may lead to distinct biofilm architectures.

[Effect of exogenous stem cells from apical papillae in the pulp revascularization treatment for the immature permanent tooth with periapical periodontitis]

Objective: To evaluate the effect of exogenous stem cells from apical papillae (SCAP) in the pulp revascularization treatment for the immature permanent tooth with periapical periodontitis in animal model. Methods: After the SCAP were isolated and cultured from the Beagle dogs, stem cell properties of these cells were characterized by analyzing their colony-forming ability, the expression of mesenchymal stem cell markers and the multidifferentiation characteristics including osteogenic, adipogenic, and chondrogenic potentials. Models of young permanent tooth with periapical periodontitis were established in dogs and the infection in each of the model tooth was eliminated by root canal irrigation and intracanal medication. After that, all of the model teeth were randomly divided into 4 groups: Group 1: normal developing teeth with no treatment applied;Group 2: teeth that periapical tissues were irritated to induce blood flowing into the root canals;Group 3: teeth that peripheral blood was delivered into the root canals;Group 4: teeth that SCAP were resuspended in peripheral blood and delivered into the root canals. In Group 2-4, firm coronal seal was performed after revascularization procedure and radiographs were taken periodically in order to observe the development of roots. After a 12-week-period, alveolar samples were collected and observed histologically. Results: The isolated SCAP showed clonogenic ability and multilineage differentiation ability including osteogenic, adipogenic and chondrogenic potentials. These cells also expressed the mesenchymal stem cell markers such as STRO-1 and CD146, while no cytokeratin was detected. The thickening of canal wall was observed radiographically 12 weeks after procedures of infection control and revascularization. Histologically, the newly formed tissues on the inner canal wall were found bone lacuna like structure in Group 2 and 3, and the new tissue formed in the Group 3 seemed easy to separate from the canal wall. The newly formed tissues in Group 4 were much thicker compare to those in the Group 2 and 3, and the dentine tubule like structure instead of bone lacuna was noticed although the orientation of these tubules were various. Conclusions: SCAP seem to play an important role in the tissue regeneration procedure when infection is well controlled in young permanent teeth with periapical periodontitis. It is difficult to achieve real tissue regeneration due to the lack of endogenous SCAP in apical area, therefore delivering adequate exogenous SCAP isolated and cultured in vitro could be a promising approach to overcome the challenge.

Revitalization of necrotic mature permanent incisors with apical periodontitis: a case report

Despite considerable focus on the regenerative endodontic treatment of immature teeth with necrotic infected pulps and apical periodontitis, little data exist with regard to its possible implementation in necrotic permanent teeth with complete apical and radicular development. The present report describes the procedures and outcome of a regenerative endodontic treatment approach in 2 previously-traumatized incisors with closed apex with apical periodontitis. A 2-visit treatment procedure was employed. At initial visit, the root canals were copiously irrigated, followed by placement of a triple antibiotic paste containing ciprofloxacin, metronidazole, and clindamycin into the root canals. After 4 weeks, the antibiotic paste was removed, and apical bleeding was initiated with size 10 hand files beyond the apices. The root canals were coronally sealed with mineral trioxide aggregate, and the access cavities were restored with bonded resin composite. At post-operative 60 months, both teeth were remained asymptomatic, with the recall radiographs showing complete resolution of apical radiolucency and reestablishment of periradicular tissues. In both teeth, the dimensions of root space remained unchanged as verified by image analysis. The revitalization protocol utilizing root canal disinfection and induced apical bleeding in necrotic, closed-apex incisors may offer a clinically acceptable alternative to conventional root canal treatment.

Clinical efficacy of main radiological diagnostic methods for odontogenic maxillary sinusitis

The objective of the study was to compare the ability of dental, ENT and radiology specialists to identify the dental cause of maxillary sinusitis with conventional computed tomography, dental and panoramic radiographs. Out of 34 dental records from subjects treated at ENT and Oral and Maxillofacial Surgery Department, LUHS Kaunas Clinics, 22 females and 12 males with the diagnosis of odontogenic maxillary sinusitis, periapical (DPA), panoramic (DPR) and computed tomography (CT) images of posterior maxilla were selected for further studies. In total, 39 sinuses with an odontogenic and 37 sinuses with only rhinogenic cause (control group) were included in the study. Sinuses with mucosal thickening less than 3 mm were excluded from the research. Each image was evaluated by 5 endodontologists, 5 oral surgeons, 6 general dentists, 6 otorhinolaryngologists and an experienced oral radiologist. DPR and DPA views were not evaluated by ENT specialists. The dental cause of maxillary sinusitis was marked according to the given scale. Intraclass correlation coefficient and ROC curve statistical analysis were performed. The best accuracy was observed when CT views were evaluated by experienced oral radiologist and oral surgeons: the AUC was 0.958 and 0.859, respectively. DPR views showed the best accuracy when evaluated by oral surgeons (0.763) and DPA-by endodontologists (0.736). The highest inter-rater agreement was observed between experienced oral radiologist and oral surgeons/otorhinolaryngologists (0.87/0.78) evaluating CT. Sensitivity and specificity of CT were 89.7 and 94.6%, DPR-68.2 and 77.3%, DPA-77.9 and 67%. Identification of dental cause of maxillary sinusitis sometimes is a challenge, which depends on radiological method and, more importantly, on evaluator's experience.

Pro-Inflammatory Cytokine TNF-α Attenuates BMP9-Induced Osteo/ Odontoblastic Differentiation of the Stem Cells of Dental Apical Papilla (SCAPs)

BACKGROUND/AIMS

Periapical periodontitis is a common oral disease caused by bacterial invasion of the tooth pulp, which usually leads to local release of pro-inflammatory cytokines and osteolytic lesion. This study is intended to examine the effect of TNF-α on BMP9-induced osteogenic differentiation of the stem cells of dental apical papilla (SCAPs).

METHODS

Rat model of periapical periodontitis was established. TNF-α expression was assessed. Osteogenic markers and ectopic bone formation in iSCAPs were analyzed upon BMP9 and TNF-α treatment.

RESULTS

Periapical periodontitis was successfully established in rat immature permanent teeth with periapical lesions, in which TNF-α was shown to release during the inflammatory phase. BMP9-induced alkaline phosphatase activity, the expression of osteocalcin and osteopontin, and matrix mineralization in iSCAPs were inhibited by TNF-α in a dose-dependent fashion, although increased AdBMP9 partially overcame TNF-α inhibition. Furthermore, high concentration of TNF-α effectively inhibited BMP9-induced ectopic bone formation in vivo.

CONCLUSION

TNF-α plays an important role in periapical bone defect during the inflammatory phase and inhibits BMP9-induced osteoblastic differentiation of iSCAPs, which can be partially reversed by high levels of BMP9. Therefore, BMP9 may be further explored as a potent osteogenic factor to improve osteo/odontogenic differentiation in tooth regeneration in chronic inflammation conditions.

Host-derived biomarkers in gingival crevicular fluid for complementary diagnosis of apical periodontitis

Apical periodontitis (AP) develops as a result of the host’s immune inflammatory response to pulpal infection of the dental root canals that leads to the generation of an apical lesion of endodontic origin (ALEO) and potentially to systemic metabolic alterations. Misdiagnosed ALEO is not infrequent due to the lack of diagnostic tools to differentiate apical lesions of different natures. Despite the conservative endodontic treatment shows a high success rate, there are refractory cases that can not be identified early enough during follow up. This evidences the need to develop complementary diagnostic tools, such as oral fluid biomarker analysis. Gingival crevicular fluid (GCF) is a serum transudate that becomes an exudate under inflammatory conditions, carrying molecules from local periodontal tissues and general circulation than can be harvested non-invasively. We aimed to review the available literature analyzing GCF composition in AP patients to evaluate whether GCF has any potential for complementary diagnosis. To the date, only few studies addressing changes of GCF components in AP are available. Most studies support GCF modifications in specific components in AP-affected teeth, suggesting that it might reflect periapical inflammation. GCF has potential for diagnostic tool, treatment follow-up and eventually to assess systemic comprise.