Survival of narrow diameter implants in supporting single crowns in the molar region of the jaw

Purpose: The present investigation assessed the success of narrow diameter implants (NDI) supporting a single crown in the molar region of the jaw. Materials and Methods: A total of 40 patients (>20 years) requiring implant supported crown in the molar region were recruited. A total of 20 patients received NDI (3.5 millimeter (mm), and another 20 received standard diameter implants (SDI), ≥3.75 mm. Crestal bone level, probing depth (PD), implant mobility, and bleeding on probing (BOP) were recorded at baseline, 6, and 12 months. Results: The control group showed 0.29 ± 0.17 of mean crestal bone loss at 6 months and 0.51 ± 0.21 at 12 months ( P < 0.001). In the test group, mean crestal bone loss of 0.18 ± 0.15 at 6 months ( P = 0.001) and 0.48 ± 0.27 ( P < 0.001) at 12 months was observed. Intergroup comparison at 12 months was nonsignificant ( P = 0.13). An increase of 0.24 ± 0.24 PD at 6 months and of 0.44 ± 0.32 at 12 months was seen in the control group ( P = 0.001). The test group revealed an increase of 0.42 ± 0.26 and 0.63 ± 0.42 PD from baseline to 6 and 12 months, respectively ( P < 0.001). Comparison between groups did not show a significant difference at the study end ( P = 0.06). Regarding BOP, a difference of 0.03 ± 0.76 ( P = 0.15) at 6 months and of 0.13 ± 0.20 ( P = 0.01) at 12 months from baseline was observed in the control group. In the test group, the difference of 0.01 at 6 months ( P = 0.31) and 0.20 at 12 months ( P = 0.006) from baseline was seen. Intergroup comparisons were nonsignificant at the end of the research ( P = 0.44). Conclusions: NDI supporting single crown functioned similarly and successfully to SDI when subjected to high masticatory loads.