METHODS: Ninety-six cavities were prepared in the maxillary first molars of 56 male Wistar rats. The dental pulps were intentionally exposed and randomly divided into four groups according to the application of pulp capping materials: MTAPPL; phosphorylated pullulan (PPL); a conventional MTA (Nex-Cem MTA, NCMTA; positive control); and Super-Bond (SB; negative control). All cavities were restored with SB and observed for pulpal responses at 1-, 3-, 7- and 28-day intervals using a histological scoring system. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U-test with Bonferroni's correction, and the level of significance was set at 0.05. DMP1 and CD34 antigen were used to evaluate odontoblast differentiation and pulpal vascularization, respectively.
RESULTS: On day 1, mild inflammatory cells were present in MTAPPL and NCMTA groups; fewer inflammatory cells were present in the PPL, whereas SB was associated with a mild-to-moderate inflammatory response. A significant difference was observed between PPL and SB (p .05). SB exhibited incomplete mineralized tissue barriers, significantly different from NCMTA, MTAPPL and PPL (p
METHODS: This systematic review was undertaken following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The protocol has been registered with the International Prospective Register of Systematic Reviews (number CRD42019127021). A comprehensive literature search was performed by 2 independent reviewers using a selected search strategy in 2 electronic databases (PubMed and Scopus) until January 28, 2019. A further search was performed manually in endodontic journals. Studies investigating or comparing at least 1 shaping property resulting from root canal instrumentation with a glide path or preflaring in human extracted teeth or clinical studies were included.
RESULTS: The literature shows that the definition of glide path and preflaring procedures remains controversial, which requires an elaboration in the American Association of Endodontists' Glossary of Endodontic Terms. After the removal of irrelevant and duplicated articles, 98 articles were included. The impact of glide path preparation and preflaring on working length determination, apical file size determination, canal transportation, separation of endodontic files, shaping time, dentinal microcrack formation, and extrusion of debris was discussed. Because of heterogeneity among the included studies, quantitative synthesis was not performed for most of the parameters.
CONCLUSIONS: An evidence-based guideline is needed to define and correlate the basic concepts and current applications of each step of contemporary advancements in root canal instruments. Glide path preparation reduces the risk of debris extrusion, has no influence on the incidence of dentinal crack formation, and improves the preservation of the original canal anatomy. The creation of a glide path may have no impact on Reciproc files (VDW, Munich, Germany) in reaching the full working length. Preflaring increases the accuracy of working length determination. Further randomized clinical trials are required to evaluate the effect of a glide path and preflaring on root canal treatment outcomes.
METHODS: Case records of patients who underwent third molar extractions at the Prince Philip Dental Hospital in Hong Kong between 3 July 2012 and 22 June 2017 were evaluated retrospectively. Data extraction was performed for indications, clinical and radiographic findings, antibiotic treatment, postoperative complications, and treatment for postoperative infection. The odds ratio (OR) for postoperative infection was estimated.
RESULTS: In total, 1615 extracted over 5 years from 992 patient records were included in the final analysis. Antibiotics were prescribed postoperatively for 44% of the extractions. The overall infection rate was 2.05%. There was no significant difference in infection rates between the groups which underwent extractions with or without antibiotics (OR = .68; P = .289). We found a significantly higher risk for infections with increasing age (P = .002).
CONCLUSION: Infection rates after third molar extraction is minimal in the current setting, with no significant benefit from postoperative antibiotic prescription.
BACKGROUND: The SDA concept refers to a specific type of dentition with intact anterior teeth and a reduction in posterior occlusal pairs. Dentists' knowledge and perceptions of the SDA concept can influence its application in clinical practice.
METHODS: A self-administered questionnaire on the SDA concept was distributed to 326 government dentists in the states of Selangor and Kuala Lumpur, Malaysia. The data were analysed using SPSS version 22 software.
RESULTS: The response rate was 84.0%. The majority of respondents had good knowledge on five of six knowledge items and good attitudes towards 10 of 17 perception items. However, only one-fifth (20.4%) reported having applied the SDA concept in the clinic. A larger number of participants who graduated locally than who graduated abroad perceived that patients <60 years of age, without molar support, can attain acceptable chewing function and that SDA treatment does not lead to loss of occlusal vertical dimension (P < 0.05). A larger number of participants with ≤5 years of work experience than with >5 years of work experience perceived that the SDA concept enables simpler treatment planning (P < 0.05). Finally, a larger number of participants who graduated abroad than who graduated locally observed that patients without molar support had temporomandibular joint problems (P < 0.05).
CONCLUSION: Although Malaysian government dentists have good knowledge and perceptions of the SDA concept, it is not widely applied in the clinic. Concerted efforts in SDA training of dentists are needed to help to shorten denture waiting lists and reduce costs.
MATERIALS AND METHODS: This is an in vitro study using two extracted sound human mandibular molars. One tooth was prepared to receive the metal onlays and another one for the RNC onlays which were fabricated using the computer-aided design and computer-aided manufacturing (CAD/CAM) technology. Twelve metals and 12 ceramic onlays were fabricated before they were placed at their respective preparation and examined under the Leica stereomicroscope, M125C (Leica Microsystems, Wetzlar, Germany) for a marginal analysis. The gap width was measured at 10 predefined landmarks which included 3 points on the buccal and lingual surfaces each and 2 points each on the mesial and distal surfaces, respectively.
STATISTICAL ANALYSIS: Mann-Whitney post hoc test was used for statistical analysis (P ≤ 0.05).
RESULTS: Overall, the RNC onlays showed significant lower marginal gap with the exception of the landmarks 5 and 6 (on distolingual) and no significant difference at landmark 7 (on midlingual). It was observed that the marginal gap were all within the clinically acceptable limit of 120 μm.
CONCLUSIONS: Based on the results obtained, it can be concluded that the RNC CAD/CAM onlays are a promising alternative to the metal onlays.