Prosthetic Outcomes and Denture Satisfaction with Two Implant-retained Mandibular Overdentures

Objective: To evaluate prosthetic maintenance and complications, and denture satisfaction in edentulous patients provided with two implant mandibular overdenture retained by Telescopic and Locator attachment systems. Method: Thirty one complete denture wearers (mean age= 61.4 years; range 48-79 years) had 2 interforaminal mandibular implants placed following a 2-stage surgical procedure. The existing conventional mandibular denture was converted into implant overdenture at abutment connection, 6-8 weeks after first stage surgery. The attachments were intraorally picked up into the existing prosthesis using intraoral reline resin (Kooliner, GC, Japan). Prosthetic complications and maintenance during the 3 years after implants were analyzed at the patient-level. Patients completed denture satisfaction questionaires before and after implants and data analyzed using global scale of score 0 (less satisfied) to 3 (very satisfied). Statistical analyses were carried out using SPSS Software version 12.0. Result:  Seventeen patients (34 implants) received Telescopic (Syncone®, Ankylos, Germany) while 14 patients (28 implants) had the Locator® (Zest Anchors, USA) attachments for overdenture retention. Statistical analysis showed no significant differences in age and gender between the attachment groups (p>0.05).  Twenty out of 31 patients (65%) experienced mandibular overdenture fracture; 7 (23%) required abutment replacement due to retention of the prostheses; 6 (19%) had at least one of the retentive attachments detached. Less frequent complications included abutment screw loosening/abutment dislodged (10%), diminished retentive forces due to wear (6%) and denture teeth detachment (6%). After adjusted for the baseline denture satisfaction  using ANCOVA, patients’ rating of satisfaction 1 year after implants showed significant difference (p=0.001) between groups. Denture Satisfaction mean score  were 2.1 (SD± 0.4) for Telescopic and 1.1 (SD±0.6) for Locator attachment systems. Conclusion: The most frequent prosthetic complication over the 3 years with mandibular implant overdenture was prosthesis fracture and patients were more satisfied with Telescopic compared to Locator attachment system for implant overdenture.