The aim of this paper is to review the literature on root canal configuration (RCC) and the frequency of occurrence of a second mesiobuccal canal (MB) in human permanent maxillary first molars where cone-beam computed tomography (CBCT) is used. Online electronic databases such as PubMed-Medline, Embase, Scopus and Cochrane Library were searched using appropriate keywords from the earliest available date until 12th June 2022, without restriction on language. In the mesiobuccal root, type I was the most frequent (33.29%), followed by types II and IV (27.18% and 26.36%, respectively). Moreover, 68.2% of maxillary first molars had a second MB canal. For both the distobuccal and palatal roots, type I was the most prevalent, with 99.08% and 97.83% occurrence, respectively. All other types were infrequent. Type I RCC is most frequent in all the roots of the maxillary first molars. Hence, care must be taken during biomechanical preparation of the MB roots.
The aim of this systematic review was to summarize the results of the studies that have compared the physical and mechanical properties of lithium disilicate (LDS) endocrowns constructed for posterior teeth to those retained by post-and-core retention systems. The review was conducted following the PRISMA guidelines. The electronic search process was conducted on PubMed-Medline, Scopus, Embase and ISI Web of Knowledge (WoS) from the earliest available date till 31 January 2023. Additionally, the studies were assessed for their overall quality and risk of bias using the Quality Assessment Tool For In Vitro Studies (the QUIN). The initial search resulted in 291 articles, out of which, only 10 studies met the eligibility criteria. In all studies LDS endocrowns were compared with various kinds of endodontic posts and crowns made from other materials. There were no definite pattern or trends observed in the fracture strengths of tested specimens. There was no predilection observed in failure patters among the experimental specimens. No predilection was observed in the fracture strengths of LDS endocrowns when compared to post-and-core crowns. Furthermore, no differences in failure patterns could be observed when both types of restorations were compared. The authors propose standardized testing of endocrowns against post-and-core crowns in future studies. In conclusion, long-term clinical trials are advocated to compare the survival, failure and complication rates of LDS endocrowns and post-and-core restorations.
Hesitancy about receiving vaccines has been deemed a global danger to public health by WHO. The sociocultural backgrounds of the people have an impact on vaccine acceptance. The purpose of this study was to examine the effect of sociodemographic factors on COVID-19 vaccination hesitancy as well as to identify the factors that contributed to COVID-19 vaccine hesitancy. Methods: A cross-sectional study was carried out to determine the primary variables causing COVID-19 vaccination hesitancy among residents of Pune. The general population was sampled through simple random sampling. The minimum sample size was determined to be 1246. The questionnaire inquired about the individuals’ sociodemographic information, vaccination status, and reasons for vaccine hesitancy. Results: In total, there were 5381 subjects, 1669 of whom were unvaccinated and 3712 of whom were partially vaccinated. Fear of adverse effects (51.71%), fear of losing a few days of work (43.02%), and inability to secure a vaccine slot online (33.01%) were the most frequently cited reasons. An older population (>60 years, p = 0.004), males (p = 0.032), those who were literate (p = 0.011), those of lower middle socioeconomic status (p = 0.001), and smokers were significantly associated with fear and mistrust of the COVID-19 vaccine, while mistrust of the vaccine was greatest among individuals from the upper and lower middle classes (p = 0.001). Conclusion: Vaccine hesitancy due to concerns about the side effects and long-term complications was prevalent among the elderly, males, those from the lower middle class, and smokers. This study emphasizes the importance of communicating effectively about the vaccine’s efficacy, its distribution, and vaccination sites.
Objectives Sterilization eliminates microbial viability by decreasing the biological load, but likewise have the ability to deteriorate the mechanical properties of an implant material. This study intended to evaluate the effect of repeated moist heat sterilization on implant–abutment interface using two different implant systems. Materials and Methods Forty screw-retained titanium implant–abutment combinations (fixture 3.5 ×10 mm, abutment 2 mm diameter), twenty each from Genesis (Aktiv Implant Systems, United States) and Bredent (SKY, Germany), were divided into four different groups (n = 10) and placed in a computer-aided diagnostic model. The abutments from each group were exposed to first and second autoclave cycle (121°C for 30 minutes), connected back to the fixture and analyzed under scanning electron microscope for marginal gap and surface roughness. Results Genesis group showed higher marginal gaps on both sides (buccal/mesial [2.8 ± 0.47]; lingual/distal [2.8 ± 0.33]), while Bredent implant–abutment system (IAS) did not show any changes in marginal gaps after autoclaving. Differences within and between the group were found to be statistically significant. Surface roughness for Genesis (243.7 ± 70.30) and Bredent groups (528.9 ± 213.19) was highest at second autoclave, with Bredent implant–abutment showing higher values for surface roughness than Genesis IAS. Conclusion Marginal vertical gap increased with autoclaving for Genesis IAS, while Bredent implant abutments were more stable. Surface roughness increases with autoclaving for both Genesis and Bredent group of IAS.