Accuracy of photogrammetric technique versus conventional impression technique for implant-supported fixed complete dentures.

内容摘要

Photogrammetry technique may provide a promising approach compared to conventional techniques for multiple implants. However, the accuracy of photogrammetric technique for implant-supported fixed complete dentures in clinical scenarios remains unclear. This study aimed to evaluate the accuracy of photogrammetric technique in horizontal impressions for implant-supported fixed complete dentures compared to conventional impression technique in edentulous jaws. Between March and December 2023, twenty edentulous arches (10 maxillary and 10 mandibular), each consisting of four to eight dental implants, were selected. For the photogrammetric technique, specialized scan bodies were placed on dental implants, followed by a digital scan using a photogrammetric camera. An intraoral scanner was then applied to obtain the information of soft tissue, which was subsequently aligned with photogrammetric data in the software using a best-fit algorithm. After one month, half of the participants were selected to repeat the procedure to assess the precision of photogrammetric technique. For conventional impressions, a two-step technique was employed. The initial impression was first completed using polyvinyl siloxane impression material to create a model. After pouring dental stone, several impression posts were attached to analogs, and a perforated custom tray was subsequently fabricated to facilitate the open-tray splinted final impressions. The final impressions, made with polyvinyl siloxane impression material, were subsequently poured with dental stone and scanned using a laboratory scanner. The deviations in distances and angles between photogrammetric technique and conventional impression were measured in the software. Distance deviations were recorded as the main outcome, while angular deviations were calculated as the secondary outcome. Deviations between photogrammetric technique versus conventional impression technique were compared using the Wilcoxon test. The significance level was set at 0.05. The overall deviation in distance was 34.46&#x2009;&#xb1;&#x2009;24.65&#xa0;mm for the maxilla and 49.80&#x2009;&#xb1;&#x2009;39.09&#xa0;mm for the mandible. In terms of angular parameters, deviation was 0.36&#x2009;&#xb1;&#x2009;0.28 degrees for the maxilla and 0.44&#x2009;&#xb1;&#x2009;0.33 degrees for the mandible. The results of the Wilcoxon test indicated no significant differences in distance and angles between photogrammetric technique and conventional impression technique, demonstrating the acceptable trueness of the photogrammetric technique for implant-supported fixed complete dentures (P&#x2009;<&#x2009;0.05). Additionally, no significant difference was found between two measurements using the photogrammetry technique over a one-month interval, indicating the promising precision of the technique (P&#x2009;<&#x2009;0.05). The photogrammetric technique could serve as a promising alternative for implant-supported fixed complete dentures in edentulous patients, demonstrating acceptable trueness and precision in the clinical environment.