Design: Randomised controlled trial.
Intervention: Patients from hospital waiting lists who had been edentulous for at least two years and required replacement of conventional dentures were recruited. Baseline quality of life and satisfaction measures were taken and all patients were provided with new conventional complete dentures (CCDs) that they wore for three months, at which point they were reassessed using the same measures. Patients were then randomly assigned either to continue with CCDs (control) or to have implant-retained overdentures (IODs) made (test group). The control group was assessed after a further three months (six months after receiving CCDs). The test group was assessed three months after receiving IODs.
Outcome measure: The outcome measures used were the Oral Health Impact Profile-49 (OHIP-49) Denture Satisfaction Questionnaire (DSQ) and the Schedule for the Evaluation of Individual Quality of Life (SEIQoL).
Results: Three months after receiving CCDs patients reported significant improvements in satisfaction and quality of life (P < 0.05). However no further improvements were seen in the control group at six months for any measure. Following placement of IODs the test groups had significant additional improvements in the functional limitation, physical pain, psychological discomfort, physical disability, social disability, psychological disability and handicap scales of the OHIP and on 10 of the 11 scales of the Denture Satisfaction Questionnaire (P < 0.05, ANOVA).
Conclusions: The findings show that, controlling for expectancy bias and variability in baseline levels, IODs significantly increase patient satisfaction, dental function and quality of life over and above those achieved with good quality CCDs.