The consequences and outcomes associated with dental implants encroaching on adjacent teeth

Background: Dental implant placement carries a risk of iatrogenic damage to adjacent root surfaces. Purpose: To classify and understand different types of trauma to the tooth root body by dental implants. Materials and Methods: This prospective case series included 43 implants placed between February 2017 and June 2020 that had primary stability and were in a position that accidentally invaded the adjacent teeth. The type and degree of the injury were evaluated clinically and radiographically. Tenderness, mobility, and sensitivity tests of the injured teeth were conducted at different visits. Implant failure was confirmed by the presence of implant mobility during the healing period. Results: Overall, 43 patients had root injuries due to dental implant surgeries. Regarding the 43 injured roots, 32 developed transient tenderness to percussion, 16 developed variable degrees of resorption in the cementum, three lost pulp sensitivity and one had persistent tenderness to percussion. No injured teeth were lost. In three patients, implant periapical lesions were confirmed radiographically as radiolucency near the apex of the involved implants. Out of the 43 implants, 11 failed and were removed within 6 months, with an implant failure rate of (25%). Conclusions: Root damage after implant surgery varies depending on the type and severity of injury. Periodic clinical and radiographical examination is necessary to monitor root resorption and implant integration and to rule out pulp necrosis.