Effect of Clinical Experience on Acquisition Time and Chairside CAD Design Accuracy: An In Vitro Study

AIM

This in vitro study aimed to assess the influence of clinical experience on two key aspects of the digital chairside workflow: intraoral scanning efficiency and the morphological accuracy of CAD-designed prosthetic crowns, by comparing three operator groups with different levels of experience.

MATERIALS AND METHODS

Thirty dental operators were divided into three homogeneous groups: ten sixth-year dental students (S), ten general practitioners (O), and ten prosthodontic specialists with advanced clinical expertise (P). The reference model featured the lower left second premolar, prepared with a horizontal finish line and supragingival margin (Fig. 1). Each operator performed three digital scans of the model following a standardized scanning strategy (Fig. 2), and completed a CAD design of a crown on the prepared tooth (Fig. 3). Digital impressions were acquired using the Primescan intraoral scanner (Dentsply Sirona), and designs were created with CEREC 5.3 software. Scan time was manually measured with a stopwatch. Three expert prosthodontists independently assessed the CAD crown quality using a Visual Analogue Scale (VAS).

RESULTS

Mean scan times were group S = 231.80 s; group O = 174.40 s; group P = 70.00 s. Mean VAS scores were S = 7.60; O = 9.00; P = 9.60 (Table 1). The Shapiro–Wilk test indicated a non-normal distribution (p > 0.005). The Kruskal–Wallis test revealed significant differences between students and prosthodontists in both scan time (p = 0.002) and CAD quality (p = 0.012) (Table 2). No significant differences emerged between students and general practitioners, nor between practitioners and prosthodontists.

CONCLUSION

Despite all operators producing clinically acceptable results, a positive correlation was found between clinical experience and performance in terms of scanning efficiency and CAD design quality.