Impact of Implant Mesiodistal Distance on Peri‐Implant Bone Loss: A Cross‐Sectional Retrospective Study
Wenwen Liu, Fangyu Zhu, Lu Han, Pei Li, Hom‐Lay WangABSTRACT
Purpose
The purpose of this study was to verify the effect of our previously proposed mesiodistal distance for multiple posterior implants on preserving peri‐implant bone, and to provide a measurable criterion for predicting implant prognosis.
Methods
One hundred and two patients with dental implants placed in the posterior free‐end edentulous arches were recruited in this cross‐sectional study. Calibrated X‐rays (peri‐apical [PA] or bite‐wing x‐ray) were collected to measure the mesiodistal space as well as the corresponding bone resorption of implants after prosthesis placement. Implants were assigned to the test/control group according to whether their mesiodistal distance following our proposed algorithm. After adjusting covariates, logistic multivariate regression analyses were performed to examine the relationship between inter‐implant distance and marginal bone loss (MBL) during each follow‐up interval. The effect of smoking habits was also analyzed.
Results
Every observation period exhibited great significance between experimental and control group on peri‐implant bone level (p = 0.006, 0.005, 0.001, 0.025, 0.001, correspondingly) and the difference had a tendency to grow as time went by except 4‐year (MD = −0.19, −0.39, −0.43, −0.30, −1.26, correspondingly). While no significant difference was observed between smokers and nonsmokers in the same group (p > 0.05).
Conclusion
The mesiodistal algorithm of 4–4.6 mm (implant to adjacent canine tooth), 7–7.4 mm, 8–8.5 mm, and 9–9.5 mm was proved to be effective for maintaining peri‐implant bone level. It was also observed in our study that the impact of inter‐implant distance outweighed that of smoking. This study provided clinicians predictable prognostic outcomes for implants and reference for deciding treatment plans.