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.