Changes in the edentulous maxilla with ball and telescopic attachments of implant-retained mandibular overdentures: A 4-year retrospective study

Objective: This retrospective study investigated the clinical and radiographic changes in the edentulous maxilla in patients with either ball or telescopic attachments of implant-retained mandibular overdentures. Method and Materials: Thirty-two completely edentu-lous patients (21 males and 11 females) received two implants in the canine region of the mandible. New maxillary complete dentures and mandibular overdentures were fabricat-ed. Overdentures were connected to the implants either with ball (group 1, n = 16) or tele-scopic (group 2, n = 16) attachments. Retention and stability of the maxillary denture as well as mucosal changes of the maxillary ridge were recorded after 4 years of denture-wearing. Traced rotational tomograms were used for measurements of maxillary alveolar bone loss. The proportional value between bone areas and areas of reference not subject to resorption was expressed as a ratio (R). Change in R immediately before (TO) and after 4 years (T4) of overdenture insertion was calculated for the anterior and posterior regions of the maxilla. Results: After 4 years of denture-wearing, maxillary denture retention was significantly higher in group 1 than in group 2, while occurrence of flabby ridges was sig-nificantly higher in group 2 than in group 1. The change in R of the anterior region of the maxilla was significantly higher than the change in the posterior region in both groups. Group 2 showed significant anterior residual ridge resorption compared to group 1. Conclusion: Telescopic attachments for implant-retained mandibular overdentures are associated with increased maxillary ridge resorption and flabbiness, and decreased maxil-lary denture retention when compared to ball attachments. © 2013 by Quintessence Publishing Co Inc.