Comparative Accuracy of Cone-Beam Computed Tomography and Clearing Technique in Studying Root Canal and Apical Morphology of Mandibular Canines.

Introduction: Knowledge about root canal anatomy improves the long-term prognosis of endodontic treatment. This study aimed to investigate the accuracy of cone-beam computed tomography (CBCT) in assessment of morphology of root canal and apex in mandibular canines compared with the clearing technique. Methods and Material: In this in vitro study, 33 extracted mandibular canines were subjected to CBCT with 0.1 mm voxel size. Number and type of canals, prevalence of accessory canals, anastomosis, apical delta and distance from apical constriction (AC) to apical foramen (AF) and to anatomic apex (AA) and also distance from AF to the AA were determined on CBCT scans. After access cavity preparation, a #8 K file was passed through the main apical foramen. Its direction and distance from anatomic apex was determined under a stereomicroscope. After clearing and staining of teeth, other criteria were determined with stereomicroscope under 16× magnification and served for comparison with CBCT data. The agreement of two methods were evaluated by intra-class correlation and kappa coefficients for quantitative and qualitative data, respectively. Results: Most (93.9%) canine teeth were Vertucci's type I, followed by type III configuration in both CBCT and clearing techniques. The results of both techniques were not in agreement for assessment of accessory canals, however acceptable agreement was noted between them for detection of apical delta and also assessment of apical foramen deviation in buccolingual and mesiodistal directions. Both of two techniques had excellent agreement for evaluating the distances from AF to AA, AC to AF and AC to AA. Conclusions: CBCT is a reliable tool in assessment of root canal and apical topography in mandibular canines, however its use in accessory canal detection is not recommended.

Management of Invasive Cervical Root Resorption in a Mandibular Canine Using Biodentine as a Restorative Material: A Case Report.

Invasive cervical root resorption (ICR) is the reversible/irreversible loss of tooth structure in the connective tissue attachment zone with unclear etiology. In the present case a history of periodontal surgery was presumed to be the predisposing factor. Early diagnosis and proper treatment may lead to long-term retention of the tooth. The tooth is usually asymptomatic and diagnosis is commonly made as a result of a routine radiographic finding. Cone-beam computed tomography (CBCT) is extremely useful in diagnosis and treatment planning of ICR. The treatment should aim toward complete removal of the resorptive defect and reconstruction by placement of a suitable filling material. The present report demonstrates the management of a mandibular canine with invasive cervical root resorption using Biodentine for the defect.

Effect of Postoperative Amoxicillin on Early Bacterial Colonization of Peri-Implant Sulcus: A Randomized Controlled Clinical Trial.

OBJECTIVES: With side effects of antibiotics taken into consideration, the necessity of antibiotic therapy after simple implant placement procedures is still a subject of debate and the existing literature on this topic is widely controversial. The aim of this study was to assess the effect of postoperative amoxicillin therapy on early colonization of peri-implant sulcus after implant placement. MATERIALS AND METHODS: In this randomized controlled clinical trial, 20 patients requiring simple implant placement were randomly allocated to test or control groups and received postoperative amoxicillin or placebo, respectively. Microbiological samples were collected on day 0 and day 7. Mann Whitney and Wilcoxon signed rank tests were utilized to evaluate changes in colony count of identified bacterial species between the test and control groups, and between day 0 and day 7. RESULTS: The decrease in the number of sensitive facultative species and the increase in the number of resistant anaerobes in amoxicillin group were statistically significant as compared to the placebo group (P=0.025 and P=0.005, respectively). The increase in the number of sensitive anaerobes in the placebo group as compared to amoxicillin group, and the decrease in the number of facultative Gram-positive cocci as compared to the placebo group were statistically significant (P=0.011 and P=0.035, respectively). CONCLUSIONS: Postoperative administration of amoxicillin resulted in an increase in the number of resistant anaerobes and a decrease in the number of sensitive facultative bacteria and facultative Gram-positive cocci, as compared to the placebo, but with no sign/symptom of infection in any group.