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Clinical investigation of CAD/CAM crowns on premolars after two years progress

Purpose: This study evaluated by the questionnaire to dentist about the use situation and prognosis of the CAD/CAM crown for the purpose to make the CAD/CAM crown successful, and at application expansion to molars or anteriors. Methods: Questionnaire was randomly carried out to CAD/CAM crowns for 2,000 dental clinics all over the country. Survey contents are disconnection of the clinical application, debonding and breakage, a future view of CAD/CAM crowns, patient evaluation, etc. Results: Total debonding ratio was found to be 8.0% and slightly decreased from previous paper (9.1%). Cross sectional analysis in bonding problem cause, there were high correspondence again to no sandblasting treatment in this study. This could be expected since a lot of dental clinic newly started to implement CAD/CAM crown in their daily treatment and diffusion on adhesion step is still on the way. The other thing to be mentioned was either debonding ratio or breakage ratio is lower than the ones with the manufacturer recommended priming/cementing system. Patient evaluation was a reply which 98.9% has satisfied very highly. Conclusions: Although there seems to be a lot of debondings, debonding ratio itself is decreasing nevertheless it is usually understandable for new NHI coverage would take some time. This fact would be worth to focus and specially be mentioned. While improving material strength and color reproducibility in the application expansion to molars or anteriors from now on further.