There is a continuing need for non-implant prosthodontic treatment yet there is a paucity of high quality randomised controlled trial (RCT) evidence for best practice. The aim was to provide RCT evidence for prosthodontic impressions. Here we report all clinical outcomes.
Method:
This was a double-blind, randomised, crossover trial comparing two impression materials for complete dentures. Using eligibility criteria, 85 patients were recruited at Leeds Dental Institute, UK. Each patient received two sets of dentures made using either alginate or silicone impressions. Unadjusted dentures were worn alternately over 2 weeks, adjusted over 2 sequential periods of 8 weeks then worn side-by-side for a further two weeks. The order of construction and wear of the dentures was randomised. The primary outcome was patient preference for unadjusted dentures. Secondary outcomes were: patients’ quality of life (OHIP-EDENT); patient-centred rating of comfort, stability and chewing efficiency before and after adjustment; patient assessment and preference of the impression materials.
Result:
78 (91.8%) patients completed the primary assessment. There was a 50% difference in preference rates (in favour of silicone) (95%CI 32.7% to 67.3%, p<0.0001). The unadjusted dentures made from silicone impressions were rated more comfortable (p=0.0039), more stable (p=0.0047) and more efficient (p<0.0001). During the two 8 week Adjustment Periods, the OHIP-EDENT score was lower wearing dentures made from silicone impressions (p=0.0014). After the ‘confirmation’ period there was significant evidence that dentures made from silicone impressions were rated as more stable (p=0.0066) and more efficient (p=0.0010) but following adjustment of the dentures there was no difference in comfort between the dentures (p=0.5417). At the end of the trial there was a 33.8% difference in preference rates for the adjusted dentures (in favour of silicone) (95%CI 14.3% to 53.3%, p=0.0016).
Conclusion: There is significant evidence that dentures made from silicone impressions were preferred by patients.