Evaluation of the effect of oral health care product on the reverse torque value of the titanium prosthetic screw of an implant-supported crown following cyclic loading

Abstract

Purpose of the study: To comparatively evaluate in vitro the effect of oral health care product on the reverse torque value of the titanium prosthetic screw of an implant-supported crown following cyclic loading.

Materials and methods: Ten titanium screw-retained implant Co-Cr crowns without application of oral health care product (Group I) and ten titanium screw-retained implant Co-Cr crowns with the application of oral health care product (GC Tooth Mousse) (Group II) were connected to their respective analogs and prosthetic screws were torqued to 30 Ncm using a digital torque meter. Reverse Torque Values were measured before cycling loading and all the twenty samples were subjected to a cyclic loading simulating six months’ duration of the function. Reverse Torque Values were subsequently measured postcyclic loading. The results were analyzed using the Paired ‘t’ test and the Independent ‘t’ test.

Results: The mean precyclic loading reverse torque values were 26.12 Ncm (Group I) and 26.57 Ncm (Group II) and the mean postcyclic loading reverse torque values were 22.49 Ncm (Group I) and 24.10 Ncm (Group II). There was no significant loss of preload for Group II test samples prior to cyclic loading compared to Group I test samples. Cyclic loading resulted in reduction of reverse torque values for both Group I and Group II test samples, indicating screw loosening. After cyclic loading, Group II test samples showed significantly higher detorque value than Group I test samples.

Conclusion: Cyclic loading resulted in screw loosening in both test groups. Screw loosening was found to be significantly less for Co-Cr prosthetic screw-retained implant crown with the application of GC Tooth Mousse than Co-Cr prosthetic screw-retained implant crown without application of GC Tooth Mousse.