Assessment of complications in adjacent natural teeth compared to contralateral teeth in single posterior implant cases

Osseointegrated dental implants represent a successful treatment modality for partial and complete edentulism. However, concerns persist regarding their impact on adjacent natural teeth. Conflicting literature exists regarding complications such as caries, mobility, and fractures in neighboring teeth, with few studies comparing these effects with those observed in contralateral natural teeth. This retrospective study aimed to assess the impact of single posterior implant-supported rehabilitation on adjacent natural teeth compared to contralateral teeth. We retrospectively screened and analyzed electronic records of all patients who underwent treatment with a single posterior implant-supported restoration (premolar or molar) at a single public dental clinic between August 2010 and August 2020. We evaluated adjacent natural teeth for four potential complications: primary caries, secondary caries, tooth cracks or fractures, and tooth mobility. Chi-square tests compared the occurrence and rates of complications between teeth adjacent to single implants and contralateral teeth. Additionally, we conducted statistical comparisons to analyze the types of complications observed in teeth adjacent to single implants. Among the 1100 patients who received posterior single implants during the study period, 167 patients (15.1%) experienced complications in a tooth adjacent to the implant. The majority of these complications were attributed to either primary (41.3%) or secondary (53.3%) caries. A significant correlation was observed between the type of complication in the adjacent tooth and the status of the control tooth (χ2 = 21.73, p = 0.01). Specifically, in cases of primary caries, the majority (68.1%) of control teeth remained classified as intact. Furthermore, in a comparison between teeth with crack/fracture complications and control teeth, 83.3% of control teeth remained intact (p = 0.01). Mobility complications were significantly associated with diabetic patients (p = 0.041) and a longer duration until implant rehabilitation (p = 0.006). Patients experiencing crack/fracture and mobility complications required a higher number of dental implants compared to other categories (p = 0.043). This study revealed a significant correlation between posterior single implants and the occurrence of complications in adjacent teeth, while most of the contralateral teeth remained intact. Clinical relevance. Meticulous monitoring of implant patients is crucial for assessing the condition of adjacent teeth and effectively manage potential complications, particularly in high-risk patients.