A randomized prospective clinical trial on the effectiveness of three treatment modalities for patients with lower denture problems. A 10 year follow-up study on patient satisfaction.

Treatment of lower denture complaints of patients with an edentulous mandible with a height of at least 15 mm can consist of meticulous construction of a new set of dentures (CD), construction of a new set of dentures following preprosthetic surgery to enlarge the denture-bearing area (PPS), or construction of an implant-retained mandibular overdenture (IRO). The aim of this prospective randomized controlled clinical trial was to evaluate the satisfaction of the above mentioned treatment modalities in resolving lower denture related complaints. Ninety edentulous patients (Cawood class IV and V, mean mandibular height 20.7 +/- 2.7 mm) were randomly assigned to one of these treatment modalities. The main outcome parameters were denture satisfaction and chewing ability, which were assessed using validated self-administered questionnaires focusing on denture-related complaints and problems with chewing different types of food. These parameters were measured before treatment, and 1, 5 and 10 years after treatment. Differences among the three groups were tested by applying a one way analysis of variance and a Tukey's test for multiple comparison. At the 1 year evaluation, significantly better scores were observed in the two surgical groups (IRO, PPS) than in the CD group (P<0.05). At 5 year evaluation the 'complaints of the lower denture' showed a significantly better score in the IRO group when compared to the PPS and CD groups (P<0.05). No significant differences were observed between the PPS and CD group. At 10 year evaluation, the intention to treat analysis revealed no significant differences between the three groups, while a per protocol analysis showed that the IRO group was the most satisfied. From this study it is concluded that both on the short and long term denture satisfaction appears most favourable in the IRO group when compared to the PPS and CD groups. Implant-retained overdentures are, therefore, a favourable treatment modality for edentulous patients with lower denture problems.