Objective: This prospective study assessed the number and reasons for post-treatment visits due to prosthodontic complications in patients treated with three types of implant treatment for the edentulous mandible.

Methods: Study groups comprised patients treated with single-implant overdenture (G-I; n = 11), 2-implant overdenture (G-II; n = 13), and 4-implant fixed prosthesis (G-III; n = 13). Programmed recall visits occurred at the 6-, 12- and 36-month follow-ups. The management of prosthodontic complications occurred continuously in unscheduled appointments. Data analysis included calculation of incidence rates, chi-square and Kruskal-Wallis tests, and Poisson regression with robust error variance to model the occurrence of visits due to prosthodontic complications.

Results: There were 89 unscheduled appointments during the entire follow-up period, ranging from 0 to 7 (mean = 2.41; SD = 2.2) per patient. No between-group differences were found regarding the frequency of unscheduled visits. However, the duration of the appointments (scheduled and unscheduled) was significantly higher for G-III (p < .001). The length of follow-up was the only predictor of the number of post-insertion visits (p = .004). The frequency of prosthodontic events was higher for G-I and G-II compared to G-III (p < .001). Nearly half of the events in G-I and G-II were matrix replacements, and artificial teeth fracture was more frequent in G-III.

Conclusions: All patients were at risk of post-delivery prosthodontic complications and required regular recall visits to achieve satisfactory function and to prevent further problems. Overdentures required higher rates of maintenance visits, particularly for replacement of the retentive inserts, while fixed implant prostheses required longer clinical times for management of complications when compared to overdentures.