Chewing efficiency and maximum bite force with different attachment systems of implant overdentures: a crossover study.

PURPOSE: This crossover study aimed to evaluate and compare chewing efficiency and maximum bite force (MBF) with resilient telescopic and bar attachment systems of implant overdentures in patients with atrophied mandibles. MATERIAL AND METHODS: Ten participants with severely resorbed mandibles and persistent denture problems received new maxillary and mandibular conventional dentures (control, CD). After 3 months of adaptation, two implants were inserted in canine region of the mandible. In a quasi-random method, overdentures were connected to the implants with either bar overdentures (BOD) or resilient telescopic overdentures (TOD) attachment systems. Chewing efficiency in terms of unmixed fraction (UF) was measured using chewing gum (after 5, 10, 20, 30 and 50 strokes), and MBF was measured using a bite force transducer. Measurements were performed 3 months after using each of the following prostheses: CD, BOD and TOD. RESULTS: Chewing efficiency and MBF increased significantly with BOD and TOD compared to CD. As the number of chewing cycles increased, the UF decreased. TOD recorded significant higher chewing efficiency and MBF than BOD. CONCLUSION: Resilient telescopic attachments are associated with increased chewing efficiency and MBF compared bar attachments when used to retain overdentures to the implants in patients with atrophied mandibles.

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 implantretained mandibular overdentures. METHOD AND MATERIALS: Thirty-two completely edentulous patients (21 males and 11 females) received two implants in the canine region of the mandible. New maxillary complete dentures and mandibular overdentures were fabricated. Overdentures were connected to the implants either with ball (group 1, n = 16) or telescopic (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 denturewearing. 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 (T0) 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 significantly 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 maxillary denture retention when compared to ball attachments.