Preloading peri‐implant crestal bone loss: A retrospective study of incidence and related factors

Abstract Background The aim of this study was to evaluate the incidence of preloading crestal bone loss (PLCBL) and to identify the patient‐related and implant‐related factors associated with PLCBL. Methods This retrospective cohort examined the dental records of patients who received at least one dental implant. PLCBL was defined as a reduction ⩾0.5 mm and severe PLCBL (primary variable) as a reduction ⩾1.5 mm in mesial and/or distal bone level, measured from the day of implant placement to uncovering or abutment installation/crown delivery. The incidence of PLCBL and patient and implant variables were recorded. Bivariate analysis and binary logistic regression identified factors associated with PLCBL ⩾0.5 mm and ⩾1.5 mm. Results A total of 746 dental implants placed in 361 patients from January 2011 to July 2021 was included in the analyses. Of the implants assessed, 24.4% ( n = 182) exhibited PLCBL ⩾ 0.5 mm and 10.5% ( n = 78) presented severe PLCBL (i.e., ⩾1.5 mm). Males (odds ratio [OR] = 1.85, 95% confidence interval [CI] = 1.11–3.07), patients with diabetes (OR = 3.33, 95% CI = 1.73–6.42), and those allergic to penicillin (OR = 3.13, 95% CI = 1.57–6.22) were more likely to experience severe PLCBL ( p < 0.05). Implants placed in the anterior area (OR = 2.08, 95% CI = 1.16–3.73), with bone‐level platform‐abutment connection (OR = 4.73, 95% CI = 1.94–11.49) and inserted supracrestally (OR = 3.77, 95% CI = 1.84–7.72), presented a greater risk of developing severe PLCBL ( p < 0.05). Implants placed in a previously grafted area presented a lower likelihood of developing severe PLCBL (OR = 0.489, 95% CI = 0.28–0.84). Conclusion The incidence of PLCBL ⩾ 0.5 mm and ⩾1.5 mm was 24.4% and 10.5%, respectively. Male sex, diabetes, allergy to penicillin, anterior location, bone‐level platform‐abutment connection, and supracrestal implant placement are potential risk factors for severe PLCBL. A previously grafted area is a potential protective factor.