Fracture resistance and failure pattern of endodontically treated maxillary premolars restored with transfixed glass fiber post: an in vitro and finite element analysis

The aims of the study were to determine the effect of different types of endodontic sealers and the presence of a horizontal glass fiber post (HGFP) on the fracture resistance and fracture pattern of mesio-occluso-distal (MOD) restored upper premolars and to analyze the stress distribution. Sixty extracted upper premolars received root canal treatment (RCT) and a MOD cavity preparation. All MOD cavities were restored with the same composite resin (CR). The 60 teeth were divided randomly into 6 groups (n = 10); Group1= AH Plus sealer; Group 2= TotalFill BC sealer; Group 3= BioRoot RCS sealer; Group 4= AH plus sealer + HGFP; Group 5= TotalFill BC sealer + HGFP; and, Group 6= Bio Root RCS sealer + HGFP. All specimens were thermocycled and subjected to cyclic loading. Next, the specimens were subjected to a static load using a universal testing machine. Data were analyzed using two-way ANOVA. Two micro-CTs of the same upper premolar, one without the HGFP and later one with HGFP inserted were made and used to create two finite element (FE) models. For the fracture resistance, two-way ANOVA revealed significant differences for the effect of HGFP (p = 0.029), but no differences for the effect of root canal sealer type (p = 0.561). The HGFP groups showed higher restorable fracture compared to groups without HGFP (p = 0.013). Finite element analysis showed that the inclusion of HGFP reduces stress concentration at the occlusal interface and cervical region. Therefore, it can be concluded that HGFP significantly increased the fracture resistance of endodontically treated upper premolars with MOD cavities and reduced the risk for non-restorable fractures. The FE analysis supports the mechanical test results.

The Potential Association Between Inflammatory Bowel Diseases and Apical Periodontitis: A Systematic Review and Meta-Analysis

Recent literature has suggested a potential association between inflammatory bowel diseases (IBD) and apical periodontitis (AP). The present systematic review and meta-analysis sought to analyse and appraise the available evidence regarding the reported association. Following 2020 PRISMA guidelines, a comprehensive search of multiple online databases (PubMed, Scopus, Web of Science, and Google Scholar) was conducted for all relevant studies published from the date of inception until 27 April 2023 using various relevant keywords. All observational studies that assessed the association between IBD and AP in humans were eligible for inclusion. The quality of the selected studies was carried out independently by two reviewers, and meta-analysis was performed using Comprehensive Meta-Analysis Version 2.2.064. Six studies (five case-control studies and one cohort study) were included. A total of 657 patients (277 with IBD) were included in 5 case-control studies, and 48,223 subjects (35,740 with AP) were included in the cohort study, where 188 developed IBD on follow-up. The pooled data from the five case-control studies revealed that IBD was significantly associated with a higher risk of AP (OR=1.71, 95% CI: 1.21-2.42; I2=10.337%, fixed-effect, p=0.002). The qualitative analysis also showed that most of the included studies found a higher mean number of teeth with AP in IBD groups than the healthy controls. Newcastle-Ottawa Scale (NOS)-based quality appraisal results demonstrated that five studies were of high quality, and one was of moderate quality. The results suggest a potential association between IBD and AP. Large-scale and prospective studies are required to further confirm and elucidate the nature of such an association.

The impact of periodontal disease on the clinical outcomes of COVID-19: A systematic review and meta-analysis

BACKGROUND

A possible relationship between periodontitis (PD) and COVID-19 and its adverse outcomes has been suggested. Hence, the present systematic review and meta-analysis aimed to investigate the available evidence regarding the potential association between periodontitis (PD) and COVID-19 and its adverse outcomes.

MATERIALS AND METHODS

PubMed, Scopus, Web of Science, and Google Scholar were searched for relevant studies published up to April 15th, 2023. Studies that evaluated the association between PD and COVID-19 were included. Risk of bias was evaluated by two reviewers, and meta-analyses were performed using RevMan 5.3 software.

RESULTS

A total of 22 studies involving 92,535 patients from USA, Europe, Asia, the Middle East and South America were included; of these, 12 were pooled into the meta-analysis. Most of the studies (19 studies) reported a significant association between PD and COVID-19. The pooled data found a significant association between PD and COVID-19 outcomes: more severe symptoms (OR = 6.95, P = 0.0008), ICU admissions (OR = 3.15, P = 0.0001), and mortality (OR = 1.92, P = 0.21). Additionally, compared to mild PD, severe PD was significantly associated with higher risks of severe COVID-19 outcomes: severe symptoms (P = 0.02); ICU admission (P = 0.0001); and higher mortality rates (P = 0.0001). The results also revealed 58% higher risk for COVID-19 infection in patients with PD (P = 0.00001).

CONCLUSIONS

The present findings suggest a possible association between poor periodontal health and the risk of poor COVID-19 outcomes. However, owing to the observed methodological heterogeneity across the included studies, further prospective cohort studies with standardized methodologies are warranted to further unravel the potential association between periodontal disease and COVID-19 and its adverse outcomes.

The influence of horizontal glass fiber posts on fracture strength and fracture pattern of endodontically treated teeth: A systematic review and meta-analysis of in vitro studies

PURPOSE

This systematic review and meta-analysis aimed to summarize available evidence regarding the effect of horizontal glass fiber posts (HGFPs) on fracture strength and fracture pattern of endodontically treated teeth (ETT) compared to controls without HGFP. The review protocol was registered on the OSF registries.

METHODS

Literature searches were conducted in MEDLINE/PubMed, Scopus, Web of Science, Embase, Google Scholar, and ProQuest for all relevant studies published up to February 2022. All in vitro studies that assessed the influence of HGFPs on fracture strength and fracture pattern of ETT whether mesio-occluso-distal or mesio-occlusal or DO cavities were considered eligible. Review Manager (RevMan) was used for the meta-analysis. Subgroup and funnel plot analyses were also performed. Quality assessment was conducted by two independent reviewers.

RESULTS

A total of 12 articles met the inclusion criteria, and 10 studies underwent quantitative evaluation. The pooled effect showed that fracture resistance of molar teeth restored with HGFP was significantly higher than teeth without HGFP (standardized mean difference [SMD]: 1.61, 95% confidence interval [CI]: 0.14, 3.09, p = 0.03), whereas marginally significant for premolars (SMD: 1.36, 95% CI: -0.00, 2.73, p = 0.05). Regarding fracture patterns, the presence of an HGFP significantly increased the occurrence of restorable fracture patterns for premolars (odds ratios [OR]: 4.15, 95% CI: 1.60, 10.82, p = 0.004) compared to controls, whereas the difference was not significant for molars (OR: 1.09, 95% CI: 0.43, 2.77, p = 0.85). Moderate risk of bias was identified in 9/12 studies; one study showed a high risk of bias and two studies showed a low risk of bias.

CONCLUSIONS

Within the limitations of this study, there is evidence from in vitro studies that the use of HGFP increases the fracture resistance of the ETT when compared to teeth without HGFP and also reduces the occurrence of non-restorable fractures for premolars. However, well-conducted in vitro and prospective clinical studies are warranted to validate this finding.

Antibacterial and anti-inflammatory efficacy of N-acetyl cysteine in endodontic treatment: a scoping review

Background

This scoping review systematically summarized the available evidence about the efficacy of N-acetyl cysteine (NAC) as an intracanal antibacterial and/or anti-inflammatory.

Methods

PubMed, Scopus, Web of Science, and Google scholar search engines/databases were searched up to February 2022 to retrieve relevant studies. The studies were evaluated for eligibility criteria, and identifying relevant studies.

Results

Out of 193 studies, 15 fulfilled the inclusion criteria and were processed for data extraction. Thirteen in vitro studies assessed antibacterial/antibiofilm efficacy of NAC, and reported good and promising efficacy: NAC was found as efficacious as the comparators (chlorhexidine, sodium hypochlorite, calcium hydroxide), or even showed higher efficacy. Regarding the anti-inflammatory efficacy of NAC, one in vitro study found it equivalent to, while one clinical trial revealed it more efficacious than calcium hydroxide.

Conclusions

There is accumulating evidence on the anti-microbial and anti-inflammatory efficacy of NAC in context of endodontics. However, further clinical trials with robust methodology and objective and reliable clinical, biological and microbial outcomes are warranted to translate its use for clinical practice on humans.

Association between dental diseases and history of stroke in the United States

Objective

This study aimed to determine the potential association between the dental diseases and self‐reported history of stroke in the United States based on data from the Third National Health and Nutrition Examination Survey (NHANES III).

Methods

Data were extracted from NHANES III. Dental variables were carious tooth surfaces, number of missing teeth, gingival bleeding, and periodontal pockets. Multiple logistic regression modeling was used to estimate the effect of these dental diseases on the self‐reported history of stroke with intent to adjust for the other potential determinants: age, sex, race, marital status, health insurance, education, exercise, body mass index, smoking, alcohol, hypertension, high serum cholesterol, and diabetes.

Results

Number of missing teeth was found to be significantly associated with the self‐reported history of stroke. Associations between the self‐reported history of stroke and caries, gingival bleeding, or periodontal pockets were not statistically significant.

Conclusions

Number of missing teeth was an independent determinant of the self‐reported history of stroke.

Association between serum zinc levels and recurrent aphthous stomatitis: a meta-analysis with trial sequential analysis

OBJECTIVES

The present meta-analysis sought to investigate the potential association between zinc levels and recurrent aphthous stomatitis (RAS).

METHODS

A comprehensive search of online databases (PubMed, Scopus, Web of Science, and China National Knowledge Infrastructure (CNKI)) was conducted to identify all English and Chinese studies published up to August 2020. All case-control studies that assessed plasma/serum zinc levels were eligible for inclusion. Data were analyzed using Comprehensive Meta-Analysis software version 2.2.046 (Biostat, Englewood, NJ, USA). Trial sequential analysis (TSA) was conducted with the trial sequential analysis program.

RESULTS

Nineteen case-control studies, involving 1079 RAS cases and 965 controls, were included in the meta-analysis. The pooled results of 19 studies showed that zinc level was significantly lower in RAS patients than in healthy controls (weighted difference in means = - 21.092, 95% CI - 26.695 to - 15.490, I² = 95.375%, P < 0.001). Upon subgroup analysis by geographic distribution of the sample (Chinese vs. others), the association remained significant in each individual subgroup, although the association was more pronounced among Chinese populations. TSA indicated that the current studies surpassed the required information size, confirming that the differences were reliable.

CONCLUSION

The results suggest a significant association between low serum zinc levels and the occurrence of RAS. Although TSA confirmed a solid conclusion, conducting large-scale studies with the highest standards of quality is encouraged.

CLINICAL RELEVANCE

Determining zinc levels should be considered in diagnosis, management, and prevention of RAS.

Management of cracked tooth using simvastatin as intracanal medicament

Cracked tooth syndrome is presented as pain associated with biting and sensitivity. Intracanal medication with simvastatin stimulates hard tissue formation at crack line, and the tooth was functioning on the follow-ups.

Orofacial manifestations of COVID-19: a brief review of the published literature

Coronavirus disease 2019 (COVID-19) has spread exponentially across the world. The typical manifestations of COVID-19 include fever, dry cough, headache and fatigue. However, atypical presentations of COVID-19 are being increasingly reported. Recently, a number of studies have recognized various mucocutaneous manifestations associated with COVID-19. This study sought to summarize the available literature and provide an overview of the potential orofacial manifestations of COVID-19. An online literature search in the PubMed and Scopus databases was conducted to retrieve the relevant studies published up to July 2020. Original studies published in English that reported orofacial manifestations in patients with laboratory-confirmed COVID-19 were included; this yielded 16 articles involving 25 COVID-19-positive patients. The results showed a marked heterogeneity in COVID-19-associated orofacial manifestations. The most common orofacial manifestations were ulcerative lesions, vesiculobullous/macular lesions, and acute sialadentitis of the parotid gland (parotitis). In four cases, oral manifestations were the first signs of COVID-19. In summary, COVID-19 may cause orofacial manifestations that might be the initial features in several cases. However, the occurrence of orofacial manifestations in COVID-19 seems to be underreported, mainly due to the lack of oral examination of patients with suspected and/or confirmed COVID-19. Oral examination of all suspected and confirmed COVID-19 cases is crucial for better understanding and documenting COVID-19-associated orofacial manifestations.

Statins-based prophylactic mouthwash and nasal spray may protect against coronavirus disease 2019

The novel coronavirus 2019 (COVID‐19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), has caused an unprecedented healthcare crisis. SARS‐CoV‐2 gets access into the human body mainly through the nose and the mouth and invades these mucosae in its destination to the pulmonary tissues. Thus, the oral and nasal mucosae serve as the main routes and reservoirs for aerosolized transmission of the viral particles to the external environment and hence infection transmission. Statins have been shown to have antimicrobial, antiviral, antifungal, anti‐inflammatory, immunomodulatory, and antioxidant properties. Therefore, we hypothesize that using statins-based prophylactic mouthwashes will reduce COVID‐19 transmission in dental settings.

N-acetylcysteine versus chlorhexidine in treatment of aphthous ulcers: a preliminary clinical trial

INTRODUCTION

This study sought to assess the efficacy of N-acetyl cysteine (NAC) in the treatment of recurrent aphthous stomatitis (RAS).

METHODS

Fifty-eight patients, aged 28 ± 9.7 years, presented with clinically diagnosed RAS to two oral medicine centers. They were assigned randomly to a single application of either NAC (200 mg dissolved in water, n = 38) or 0.12% chlorhexidine digluconate (CHX, n = 20) mouthwashes for 30 seconds. Pain was measured using a Visual Analog Scale (VAS). The size of the ulcer was measured through its greatest dimension using a periodontal probe. These two measurements were taken pre-application (day 1) and 2nd, 4th, and 6th day post-application. Average time (in days) until complete healing was assessed.

RESULTS

Of all participants, 33 (57%) were females; 34 (59%) married; 29 (50%) reported a family history of aphthae; and 51 (88%) were affected with minor RAS. There were greater improvement in pain from day 1 with NAC on the second day (-3.0 ± 2.0 versus -1.8 ± 1.9; p = .028) and on the fourth day (-5.0 ± 2.6 versus -3.4 ± 2.7; p = .041). The differences with regard to the change in ulcer size and average healing time were not significant between NAC and CHX.

CONCLUSION

Single application of NAC results in a clinically significant reduction of RAS-associated pain within one day of application and is more effective than CHX.

Subgingival microbiome of experimental gingivitis: shifts associated with the use of chlorhexidine and N-acetyl cysteine mouthwashes

This study aimed to demonstrate subgingival microbial changes associated with development, prevention, and treatment of experimental gingivitis using chlorhexidine (CHX) and N-acetylcysteine (NAC) mouthwashes. This randomized clinical trial comprised two parts: a 3-week prevention sub-study in which 30 study subjects were equally assigned to either mouthwash or placebo while developing experimental gingivitis; followed by a 2-week treatment sub-study in which 20 subjects with experimental gingivitis were assigned to either mouthwash. Subgingival samples were collected at the beginning and end of each sub-study for microbial profiling with 16S rRNA gene sequencing. As expected, CHX was effective in both preventing and reversing experimental gingivitis; NAC had a modest effect. Gingivitis was associated with enrichment of TM7 HOT-346/349, Tannerella HOT-286, Cardiobacterium valvarum, Campylobacter gracilis, Porphyromonas catoniae, Leptotrichia HOT-219, and Selenomonas spp. At the phylum/genus level, TM7 showed the strongest association. Gingival health was associated with increased abundance of Haemophilus parainfluenzae, Lautropia mirabilis, Rothia spp., Streptococcus spp., and Kingella oralis. CHX demonstrated largely indiscriminate antimicrobial action, resulting in significant drop in biomass and diversity. Our results substantiate the role of specific oral bacterial species in the development of gingivitis. They also indicate that NAC is not a promising mouthwash at the concentration tested.

Management of a failed endodontic treatment for a maxillary second molar with two separate palatal roots

Complexity of root canal system and variations in internal anatomy of teeth require careful analysis of preoperative cone beam computed tomography or multiangle radiographs to locate and identify possible extra roots or canals. A fourth canal in upper molars is expected, and much effort should be made when planning the endodontic treatment to avoid missing a canal.

Effect of Apical Patency on Postoperative Pain: A Meta-analysis

INTRODUCTION

This systematic review and meta-analysis assessed the available evidence regarding the effect of apical patency versus nonpatency on postendodontic pain in adult patients.

METHODS

The study adhered strictly to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PubMed, Scopus, MEDLINE via Ovid, Google Scholar, and the Web of Science databases were searched up to April 2018 to retrieve the most relevant studies. Two authors evaluated the studies for eligibility criteria and assessed the risk of bias using the Cochrane tool. The weighted means were calculated using a fixed effects model. When statistically significant (P < .1) heterogeneity was detected, a random effects model was used to assess the significance of treatment effects.

RESULTS

Five studies were identified for this systematic review; 4 were included in the meta-analyses. Two studies revealed a low risk of bias, whereas 3 studies revealed a high risk of bias. Because of the significant heterogeneity between studies, a random effects model was used. The meta-analysis showed that the apical patency resulted in less postoperative pain compared with nonpatency, but the difference was not statistically significant. Moreover, no statistically significant difference was found with regard to analgesic consumption.

CONCLUSIONS

Considering the limitations of this study, it was concluded that maintaining apical patency during routine endodontic treatment was not associated with an increased incidence of postoperative pain in adult patients.

Effect of adjunctive use of systemic antioxidant therapy (N-acetylcysteine) on soluble receptor activator nuclear factor κB ligand levels in gingival crevicular fluid following surgical periodontal treatment for chronic periodontitis

N-acetylcysteine (NAC) is an anti-oxidant drug that has been used as a mucolytic agent and a paracetamol antidote for many years. This study was designed to determine the efficacy of the adjunctive use of NAC for periodontal treatment. Thirty subjects with moderate-to-severe chronic periodontitis were randomized to surgery with NAC (600 mg; S-NAC), surgery only (S-nonNAC), and healthy control groups. Gingival crevicular fluid (GCF) samples were obtained from all patients and sRANKL levels were determined by enzyme-linked immunosorbent assay at baseline, and 1, 3, and 7 months post-surgery. Plaque and gingival indices, probing depths, and clinical attachment levels were recorded at the same time. There was a significant reduction in probing depth at 3 months in the S-NAC group when compared to the S-nonNAC group (P < 0.05). However, no statistically significant differences in plaque and gingival indices, probing depths, clinical attachment levels, and sRANKL levels in GCF were noted between the surgical treatment groups at the end of 7 months. Hence, the use of adjunctive NAC resulted in a significant reduction in probing depths in the S-NAC group when compared to the S-nonNAC group at 3 months, but no statistically significant differences in GCF sRANKL levels were observed in the sites that underwent surgical treatment with or without NAC at different time intervals.

Influence of Different Obturation Systems on the Fracture Resistance of Endodontically Treated Roots

Objective: This study aimed to compare the fracture resistance of endodontically treated roots filled by different obturation systems. Material and methods: Ninety-six upper central incisors were used and decoronated, retaining 12 mm of the roots. On the basis of obturation systems, the roots were divided into 4 groups (n=24): Group1 (COGR): control group (unprepared, unfilled), Group 2 (AVGR): ActiV GP points/ActiV GP sealer, Group3 (GPGR): Gutta percha points/AH plus sealer, and Group4 (GAGR): Gutta percha points/ActiV GP sealer. The last three groups were obturated with the single cone technique. The roots were then stored in 100% relative humidity at 37 °C for 2 weeks. A vertical compressive force was exerted with a universal testing machine until a fracture occurred. Data were statistically analyzed with one-way ANOVA. Results: Mean (SD) failure loads for groups ranged from 920.51 ± 210.37 to 1113.44 ± 489.42 N. The fracture resistance between the different study groups indicated no statistical difference. Conclusions: ActiV GP system did not exert a significant effect on the fracture resistance of endodontically treated teeth.