Assessment of Incidence, Management and Contributory Factors of Root Canal Instrument Separation in an Endodontics Post- Graduate Program: A Retrospective Clinical Study.

BACKGROUND: The successful outcome of nonsurgical root canal treatment (NS-RCT) is largely dependent on the technical quality of the procedure. OBJECTIVE: To investigate the incidence of separated instruments in endodontic postgraduate clinics between January 2018 and December 2021, and to determine the potential contributory factors that increase the risk of instrument separation. MATERIALS AND METHODS: A retrospective observational study was conducted in the Department of Endodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia. Data was collected to determine the incidence of separated instruments and their associated variables. Seven variables were analyzed separately: nonsurgical initial or retreatment case, tooth type, tooth arch, tooth location, canal type, root curvature, level of fracture, and file type. RESULTS: A total of 3150 cases were treated, of which 108 cases had separated instruments. The overall incidence of instrument separation was 3.4% while 53.7% of separated instruments occurred in the mandibular molars, followed by 42.6% in the maxillary molars. The highest frequency of instrument separation was recorded in the mesiobuccal canal (35.2%). The level of separation was found to be statistically significant in relation to the management (P < .001). CONCLUSION: Nickel-titanium instruments tend to separate more inside the root canal system than stainless steel instruments. However, under the limitation of this study, the incidence of instrument separation is still quite low, even with postgraduate endodontic residents with limited experience.

Thumb radial abduction angle and its association with handgrip strength, dexterity and carpel tunnel syndrome susceptibility among saudi dental students.

BACKGROUND: Dental professionals are prone to carpal tunnel syndrome (CTS) and other nerve-related disorders as they perform repetitive wrist work with static physical position for long hours. OBJECTIVES: To evaluate the relationship of thumb radial abduction angle with handgrip strength, hand dexterity, and CTS susceptibility among Saudi senior dental students and interns. The study also intends to compare thumb radial abduction angle based on the gender. METHODS: A convenient sample of 100 Saudi dental students and interns participated in the study. Their handgrip strength, dexterity, and thumb radial abduction angle were measured by the use of Jamar dynamometer, nine-hole peg test, and goniometer, respectively. Questionnaires were distributed among the participants to assess CTS susceptibility and its association with thumb radial abduction angle. Regression analysis, Pearson's correlation, and independent t-test were performed to analyze the data. RESULTS: A significant correlation between thumb radial abduction angle and handgrip strength was observed. An association of handgrip strength with CTS susceptibility was also found. No significant relationships were drawn considering hand dexterity. Handgrip strength and dexterity were found to be higher in males when compared to females, however, females were observed to be more susceptible to CTS. CONCLUSION: The study concludes a significant association between thumb radial abduction angle and handgrip strength that is further related with CTS. The results of the study can be used as a foundation for several academicians' research in this domain.