Effect of time and local factors on the stability of hydrophilic self-tapping tissue-level implants: 1-year prospective study.

Purpose: To evaluate changes in implant stability quotient values of hydrophilic tissue-level implants over time, and to investigate the influence of local factors on variations in these values.

Methods: Fifty tapered, self-tapping, tissue-level implants with a hydrophilic surface were placed and monitored for 12 months. Implant stability quotient values were recorded at the time of insertion (T0) and monthly thereafter for 12 months. All implants were restored with screw-retained restorations 2 months after placement. A repeated measures analysis of variance was used to evaluate the trends in implant stability quotient values over time. A multiple linear regression model was employed to determine the impact of various factors on changes in implant stability quotient values.

Results: Implant stability quotient values decreased from T0 to T1, although this reduction was not statistically significant (P = 0.28). The greatest decrease was observed in implants with initially high implant stability quotient values at T0 (P 0.05). Values increased significantly at each subsequent time point (P 0.001). A significant time effect was noted between immediate and delayed placement protocols (P 0.05), with immediate implants demonstrating lower initial implant stability quotient values but a steeper increase over time. Implants placed in the mandible and wider implants in molar sites showed higher implant stability quotient values compared to those placed in the maxilla and narrower implants (mandible vs maxilla P 0.05; wide molar vs regular premolar P 0.05). Insertion torque was positively correlated with implant stability quotient values at T0 (P 0.001).

Conclusions: The lowest implant stability quotient value was recorded 1 month after implant placement, and then increased consistently throughout the study period without reaching a plateau. Implants placed immediately showed a steeper improvement in implant stability quotient values.

Conflict-of-interest statement: The authors declare there are no conflicts of interest relating to this study.