Impression evaluation and laboratory use for single-unit crowns

Abstract

Background Objectives were to: (1) determine the likelihood that a clinician accepts an impression for a single-unit crown; and (2) document crown remake rates. Methods A questionnaire was developed that asked dentists about techniques used to fabricate single-unit crowns. Dentists were shown photographs of 4 impressions and were asked to accept or reject the impression. Answers were correlated with dentist and practice characteristics. Other questions pertained to laboratory usage and crown remake rates. Results Response rate was 83% (1,777 of 2,132 eligible dentists). Of the impressions evaluated, 3 received consistent responses, with 85% agreement. One impression was more equivocal; 47% accepted the impression. The likelihood of accepting an impression was significantly associated with the clinician’s sex, race, ethnicity, and practice busyness. Clinicians produce 18 crowns per month on average, and 9% used in-office milling. Most (59%) reported a remake rate of less than 2%, while 17% reported a remake rate >4%. Lower remake rates were significantly associated with more-experienced clinicians, optical impressions, and not using dual-arch trays. Conclusions While dentists were largely consistent in their evaluation of impressions (greater than 85%), non-clinical factors were associated with whether an impression was accepted or rejected. Lower crown remake rates were associated with more-experienced clinicians, optical impressions, and not using dual-arch trays. Practical Implications These results provide a snapshot of clinical care considerations among a diverse group of dentists. Clinicians can compare their own remake rates and impression evaluation techniques to this sample when developing best practice protocols.

Preparation Techniques Used to Make Single‐Unit Crowns: Findings from The National Dental Practice‐Based Research Network

“…35–38 However, it is unclear as to why females use more shoulder preparations than males, for both anterior and posterior crowns. It is tempting to speculate that females use all-ceramic materials more often than males, but results from this survey suggested the opposite.…”