What is the evidence base for the efficacies of different complete denture impression procedures? A critical review

Objectives: Many procedures used in prosthodontics, including the materials and methods used for complete denture impressions, lack support of good evidence. The aims were to systematically, and critically, review the literature on complete denture impression materials and methods to identify an impression procedure that can be considered expedient for achieving a satisfactory clinical outcome for complete denture wearers. Data and sources: MEDLINE/PubMed and the Cochrane Library were searched for studies on impression procedures used in the clinical fabrication of complete dentures. The search focused on best available evidence with respect to clinical outcome. Study selection: PubMed listed 1201 titles for the combination terms of complete denture and impression. Five relevant randomized controlled trials were identified. No review of complete denture impressions was found in the Cochrane Library. Results: Two-step procedures for complete denture impressions dominate all textbooks, teaching and specialist practice, despite an absence of convincing evidence of its superiority. No controlled studies supporting the use of border moulding, post-dam, and functional and mucostatic impressions, were identified. Two studies showed that a one-step method using alginate in a stock tray offers a similar clinical result to more complicated, expensive and time-consuming two-step material and technique combinations. Conclusions: There was no support for the frequent textbook statement that the two-step procedure is necessary and superior to the one-step method. While some special clinical situations may benefit from other combinations of materials and techniques, the results suggest that the simple and inexpensive one-step procedure can serve the needs of the majority of edentulous patients. Clinical significance: In spite of the fact that two-step procedures for complete denture impressions dominate textbooks, teaching and specialist practice, the results of this review suggest that a simple and inexpensive one-step procedure can serve the needs of the majority of edentulous patients. (C) 2012 Elsevier Ltd. All rights reserved.