Effect of different maintenance time of torque application on detorque values of abutment screws in full-arch implant-supported fixed prostheses.

BACKGROUND: The effect of different maintenance time of torque application and screw loosening in full-arch implant-supported prosthesis remains uninvestigated. PURPOSE: To examine the effect of different maintenance time of torque application on detorque values of implant abutment screw in full-arch implant-supported fixed complete denture. MATERIALS AND METHODS: Passively fitting framework supported by four implants stabilized on resin model torqued to 35 N-cm and maintained for different times; instant torque application (protocol A), 10 seconds (protocol B), and 30 seconds (protocol C) were used. Detorque values were recorded during removal of the screws. Comparison between mean torque and detorque values were made using paired sample t-test. The mean removal torque values of each protocol were compared using three-way analysis of variance (ANOVA). RESULTS: The mean removal torque values were lower than the applied torque for all the protocols. The highest mean removal torque value was found in the immediate protocol (A) (24.44 ± 1.7), followed by the 30 seconds protocol (C) (23.37 ± 1.75), and then by the 10 seconds protocol (B) (23.35 ± 1.6). All these differences were found to be statistically significant between torque and detorque values (P = .001). However, the differences among detorque values were not statistically significant (P > .05). CONCLUSION: The application of 35 N-cm for different maintenance time of torque application on implant abutment screw did not appear to affect the detorque value in a multiple implant-supported fixed prosthesis. Maintaining the torque for prolonged time (10 seconds or 30 seconds) was not significantly associated with higher preload than instant torque application in full-arch implant-supported prosthesis.

Adherence of Candida to complete denture surfaces in vitro: A comparison of conventional and CAD/CAM complete dentures.

PURPOSE: The goal of this study was to compare the adhesion of Candida albicans to the surfaces of CAD/CAM and conventionally fabricated complete denture bases. MATERIALS AND METHODS: Twenty discs of acrylic resin poly (methyl methacrylate) were fabricated with CAD/CAM and conventional procedures (heat-polymerized acrylic resin). The specimens were divided into two groups: 10 discs were fabricated using the CAD/CAM procedure (Wieland Digital Denture Ivoclar Vivadent), and 10 discs were fabricated using a conventional flasking and pressure-pack technique. Candida colonization was performed on all the specimens using four Candida albicans isolates. The difference in Candida albicans adhesion on the discs was evaluated. The number of adherent yeast cells was calculated by the colony-forming units (CFU) and by Fluorescence microscopy. RESULTS: There was a significant difference in the adhesion of Candida albicans to the complete denture bases created with CAD/CAM and the adhesion to those created with the conventional procedure. The CAD/CAM denture bases exhibited less adhesion of Candida albicans than did the denture bases created with the conventional procedure (P<.05). CONCLUSION: The CAD/CAM procedure for fabricating complete dentures showed promising potential for reducing the adherence of Candida to the denture base surface. Clinical Implications. Complete dentures made with the CAD/CAM procedure might decrease the incidence of denture stomatitis compared with conventional dentures.

Botulinum Toxin for the Treatment of Gummv Smile.

AIM: The aim was to evaluate the effect of botulinum toxin (Botox) injections as a conservative treatment for gummy smile. MATERIALS AND METHODS: An experimental in vivo study was conducted at a dermatology clinic in Riyadh in January 2016. The study included 23 female patients who ranged from 20 to 50 years and were treated with Botox injections due to excessive maxillary gingival display. The patients with short clinical crowns or long maxilla, those who were pregnant or breastfeeding, and patients with neuromuscular disorders were excluded. Patients received Botox type I, injected 3 mm lateral to the alar-fascial groove at the level of the nostril opening at the insertion of the levator labii superioris alaeque nasi muscle. Photos were taken of the patient's smile before and after the treatment and were then uploaded to the SketchUp program to calculate improvements in gingival display. The distance from the lower margin of the upper lip to the gingival margin was calculated pre- and posttreatment. The amount of improvement was calculated as (pre-Botox treatment - post-Botox treatment/pre-Botox treatment × 100). The mean percentage of the total improvement was analyzed. RESULTS: A total of 23 female patients received treatment to improve their gummy smile. Improvement was clear 2 weeks after Botox injection. The mean percentage of improvement in the gingival display was 99.6%. CONCLUSION: Botox type I is an effective conservative technique to improve gummy smile caused by muscular hyperfunction. CLINICAL SIGNIFICANCE: Patients' retention highly indicated that they were satisfied with the provided treatment by Botox injections. Improving the quality of life with least painful experience and immediate results was the major advantage for Botox type I.

Antibiotic prophylaxis against infective endocarditis in adult and child patients. Knowledge among dentists in Saudi Arabia.

OBJECTIVES: To evaluate dentists' knowledge regarding the prevention of infective endocarditis in Saudi Arabia and their implementation of the 2007 American Heart Association guidelines. METHODS: In this cross-sectional study, in March 2014, 801 dentists who practice in different regions of Saudi Arabia completed a questionnaire regarding the need for antibiotic prophylaxis for specific cardiac conditions and specific dental procedures, prophylaxis regimens in adults and children, and recommendations for patients on chronic antibiotics, and in dental emergencies. The data were analyzed using one-way analyses of variance (ANOVAs) and independent t-tests, and a p-value less than 0.05 was considered statistically significant. RESULTS: The total knowledge level regarding antibiotic prophylaxis among all participants was 52.2%, with a significant difference between dentists who graduated before and after 2007. Comparing the level of knowledge among different dental specialists, surgeons and periodontists had the highest level of knowledge regarding the use of antibiotic prophylaxis. Amoxicillin was prescribed as the drug of choice by 63.9% of the participants. CONCLUSION: This study emphasized the need for continuous education and for formal inclusion of the guidelines in the students' curriculum, as well as for strategic placement of the guidelines in locations throughout dental clinics.

Volumetric measurements of removed tooth structure associated with various preparation designs.

The amount of tooth structure that is removed as a consequence of tooth preparation has rarely been quantified. The aim of this study was to quantify the volume of reduction of tooth structure associated with different commonly used preparation designs. Eighty extracted teeth were divided into eight groups according to the type of preparation design and tooth type. Each specimen underwent pre- and post preparation scanning using microcomputed tomography. The volume of the resultant tooth structure removed was analyzed. Significant differences in the amount of tooth structure removal were noted between types of coverage and types of teeth.