Accuracy and feasibility of 3D-printed custom open trays for impressions of multiple implants: A self-controlled clinical trial

Abstract

Statement of problem: Three-dimensionally printed custom open trays have become a popular option in clinical implant dentistry because of advantages such as individualization, efficiency, and effectiveness. However, clinical evidence on their accuracy and feasibility is lacking.

Purpose: The purpose of this clinical study was to evaluate the accuracy and feasibility for impressions of multiple implants by using 3D-printed custom open trays versus conventional custom open trays.

Material and methods: Twenty-two partially edentulous individuals needing impression making for restorations supported by multiple implants were enrolled. Two types of custom open trays were made for each participant, a 3D-printed tray (test) and a conventional tray (control). With a splinted technique, silicone definitive impressions were obtained with the 2 custom open trays and poured with Type IV dental stone. Impression accuracy (primary outcome) was evaluated by measuring linear distances and the marginal gaps between the implant replicas and verification devices on the test and control casts. Clinical tray fit, impression quality, and cast quality were rated by an independent technician through a visual analog scale (VAS). The fabrication time and cost of the 2 types of custom open trays were recorded. The feasibility of 3D-printed trays was determined from these outcomes. The paired Student t test and Wilcoxon rank-sum tests were used for statistical analysis (α=.05).

Results: For impression accuracy, no statistically significant difference was found between test and control groups (P>.05). In terms of clinical tray fit, impression quality, and cast quality, no statistically significant difference was found (all P>.05). Regarding fabrication time and cost, the test group (57.65 ±6.49 minutes, 0.37 ±0.07 United States dollars [USD]) exhibited superiority over the control group (101.96 ±2.92 minutes, 4.41 ±0.37 USD) (both P<.001).

Conclusions: Within the limitations of this study, the 3D-printed custom open trays were clinically accurate, efficient, and cost-effective for impressions of multiple implants.