Assessment of Bone Loss Around Platform-Switching Subcrestal Implants: A Quasi-Experimental Study

Replacement of lost teeth with implants is a well-known and accepted worldwide treatment. A healthy amount of bone surrounding the implant plays a vital role in osseointegration and is required for implant success. This study aimed to evaluate the efficacy of single-crown rehabilitation of subcrestal implants in terms of bone loss (BL) and overall success.

Twenty healthy patients requiring implant placement to replace single hopeless teeth or extracted teeth were recruited for this prospective study. In these 20 patients, the implants were placed at the subcrestal level. Bone levels around the implant placement (T0) and one year after loading (T1) were estimated in this study. A paired t-test was used for intra-group comparisons, multivariate linear regression analysis was conducted to analyze the effect of independent variables on BL, and a correlation test was used to correlate various variables. Statistical significance was maintained at a p value of 0.05.

The outcomes demonstrated statistically significant BL at the mesial and distal sides of the subcrestal implants at one-year follow-up (p<0.05). Age and sex were not significantly correlated with BL in any region (p>0.05). Brushing frequency, probing depth (PD), and bleeding index (BI) showed statistically significant effects on BL (p<0.05). A weak correlation was observed between age and other variables, with age and mesial BL showing a low correlation of 0.016.

Within the parameters of this prospective study, it could be proposed that subcrestal implants caused significant BL. The PD, BI, and brushing frequency were significant predictors of BL.