Evaluation of Torque Maintenance in Implant abutment interface using a Novel Sealant: An In Vitro Study

Abstract

Aim and Objective: Implant abutment microgap being one of the major problem leading to screw loosenings. The aim of this study was to evaluate the effect of chitosan-based sealant on the implant abutment interface by evaluating the abutment screw torque loss.Materials and Methods: CH/GP (chitosan β glycerophosphate) hydrogel was fabricated. Two experimental groups with thirty implant abutment internal connections (ADIN,Isreal) were used. Each system was divided into two groups with and without sealant(N=30). The sealant group was loaded with hydrogel while the control were bare implants. The abutments were tightened to the fixtures with a torque of 30 N.cm for all samples. Additionally, metal ceramic crowns were cemented onto each abutment. The implants underwent cyclic loading in chewing simulator, with 500,000 cycles at a force of 75 N and a frequency of 2 Hz applied along the longitudinal axis of each sample. The detorque value was measured for all samples using a digital torque meter. Data were analysed using an independent samples t-test, with significance set at P < 0.05.Results: The mean reversed torque of the study group (23.64 ± 1.69 N.cm) was significantly higher than the control group (17.34 ± 1.57 N.cm;P <0.0001). The difference between the initial tightening torque value (TTV) and RTV in the study group was significantly lower than that in the control group .Conclusion: The application of the hydrogel was found to minimize torque loss at the implant–abutment interface, suggesting its potential use in clinical practice to decrease the likelihood of screw loosening.Clinical Implication: The chitosan hydrogel tested shows a potential to reduce the risk of mechanical complication for implant system and may extend their longevity.