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

Evaluation of shear bond strength of two resin-based composites and glass ionomer cement to pure tricalcium silicate-based cement (Biodentine®)

Objectives: Tricalcium silicate is the major constituent phase in mineral trioxide aggregate (MTA). It is thus postulated that pure tricalcium silicate can replace the Portland cement component of MTA. The aim of this study was to evaluate bond strength of methacrylate-based (MB) composites, silorane-based (SB) composites, and glass ionomer cement (GIC) to Biodentine® and mineral trioxide aggregate (MTA). Material and Methods: Acrylic blocks (n=90, 2 mm high, 5 mm diameter central hole) were prepared. In 45 of the samples, the holes were fully filled with Biodentine® and in the other 45 samples, the holes were fully filled with MTA. The Biodentine® and the MTA samples were randomly divided into 3 subgroups of 15 specimens each: Group-1: MB composite; Group-2: SB composite; and Group-3: GIC. For the shear bond strength (SBS) test, each block was secured in a universal testing machine. Results: The highest (17.7±6.2 MPa) and the lowest (5.8±3.2 MPa) bond strength values were recorded for the MB composite-Biodentine® and the GIC-MTA, respectively. Although the MB composite showed significantly higher bond strength to Biodentine (17.7±6.2) than it did to MTA (8.9±5.7) (p<0.001), the SB composite (SB and MTA=7.4±3.3; SB and Biodentine®=8.0±3,6) and GIC (GIC and MTA=5.8±3.2; GIC and Biodentine=6.7±2.6) showed similar bond strength performance with MTA compared with Biodentine (p=0.73 and p=0.38, respectively). Conclusions: The new pure tricalcium-based pulp capping, repair, and endodontic material showed higher shear bond scores compared to MTA when used with the MB composite

Outcome of non-surgical re-treatment

The purpose of this review was to critically analyze the relevant literature in order to synthesize an overview on the clinical outcomes (radiographically judged periapical healing and tooth survival) following root canal re‐treatment and the factors influencing them. A further aim was to explain the findings on the basis of current knowledge and understanding. The relevant literature was captured and critiqued using the principles of a systematic review. The data were classified into a coherent structure for analyses and presentation but are not presented as a systematic review; rather, the authors have chosen a narrative style to enable integration of the clinical outcomes with relevant findings from laboratory and animal studies. Overall, the outcomes were similar to those for teeth undergoing primary treatment with common factors influencing the outcomes. The major differences between the outcomes of primary and secondary root canal (re‐)treatment reside only in the ability to predictably access and negotiate the root canal system to the (residual) apical infection. The data offer a very favorable prognosis for non‐surgical root canal re‐treatment performed to guideline standards

Canal configuration of mandibular first premolars in an Egyptian population

AbstractThe purpose of this study was to investigate canal configuration of mandibular first premolars in an Egyptian population. Two hundred fifty human extracted mandibular first premolars were collected from Egyptian patients and a small hole in the center of the occlusal surface of each tooth was made perforating the roof of the pulp chamber. Teeth were decalcified by immersing in nitric acid and dehydrated in ascending concentrations of ethyl alcohol. A waterproof black ink was passively injected from the occlusal hole into pulp system and stained teeth were immersed in methyl salicylate solution for clearing. Standardized pictures of the cleared teeth were obtained and anatomical features of the root canal were observed. The average length of the mandibular first premolar teeth was 22.48±1.74mm, one-rooted teeth were 96.8% and the two-rooted were 3.2%. Vertucci Type I canal configuration represented the highest percentage (61.2%) followed by Type V (16.4%), Type IV (13.2%), Type II (5.6%) and Type III (2.8%). Vertucci Type VI canal configuration represented the lowest percentage (0.4%) and a complex configuration was found in one tooth. Accessory canals were detected in 22.8% and inter-canal connections were observed in 24.8% while 54% showed apical delta. Such knowledge is clinically useful for localization and negotiation of canals of mandibular first premolar, as well as their subsequent management in Egyptian population

Marginal adaptation in vitro and clinical outcome of Class V restorations

OBJECTIVES: We examined the correlation between the quantitative margin analysis of two laboratory test methods (Berlin, Zurich) and the clinical outcome in Class V restorations. METHODS: Prospective clinical studies with an observation period of at least 18 months were searched in the literature, for which laboratory data were also available. The clinical outcome variables were retention loss, marginal discoloration, detectable margins and secondary caries. Forty-four clinical studies matched the inclusion criteria, including 34 adhesive systems for which laboratory data were also present. For both laboratory test methods and the clinical studies, an index was formulated to better compare the in vitro and in vivo results. Linear mixed models which included a random study effect were calculated. As most clinical data were available for 12 and 24 months, the main analysis was restricted to these recall intervals. RESULTS: The comparative analysis revealed a weak correlation between the clinical index and both in vitro indices. The correlation was statistically significant for the Berlin method but not for the Zurich method and only present if studies were compared which used the same composite in the in vitro and in vivo study. When defining specific cut-off values, the prognosis for the good clinical performance of an adhesive system based on in vitro results was 78% (Berlin) or 100% (Zurich). For poor performance it was 67% and 60%, respectively. No correlation was found between both in vitro methods. SIGNIFICANCE: The surrogate parameter "marginal adaptation" of restorations placed in extracted teeth has a mediocre value to predict the clinical performance of an adhesive system in cervical cavities. The composite is an important factor for a successful prediction. The comparison between in vitro/in vivo is sometimes hampered by the great variability of clinical results on the same adhesive system