Replacement of Unesthetic Posterior Metal Crowns with Monolithic Zirconia Crowns: A Case Report

Advances in metal-free materials and the popularization of Computer-Aided Design and Manufacturing (CAD/CAM) have led to the wide clinical use of all-ceramic crowns for esthetic restorations. A 72-year-old woman presented to our hospital with unesthetic restorations on the right upper and lower posterior teeth. Intraoral examination revealed poorly fitting metal crown margins. Defective prostheses were removed, and provisional restorations were provided to stabilize the mandibular position. Optical impressions and the maxillomandibular relationship were recorded using an intraoral scanner, and monolithic zirconia crowns were fabricated using CAD/CAM technology for complete veneer crown restorative treatment. Occlusal examination revealed an improvement in occlusal force distribution at initial examination (right side: 33.5%, left side: 66.5%) after placement of the zirconia crowns (right side: 54.9%, left side: 45.1%). Occlusal force and occlusal force distribution area also showed an increasing trend. The Oral Health Impact Profile short form (OHIP-14) score decreased from 7 points at initial examination to 0 points after prosthodontic treatment. Appropriate diagnosis and treatment planning contributed to the increased occlusal force and balanced occlusal force distribution. Therefore, the present case indicates the potential of monolithic zirconia crowns to achieve both esthetic and stable functional outcomes.

无金属材料的进步以及计算机辅助设计与制造（CAD/CAM）技术的普及，使得全瓷冠在美学修复中得到了广泛的临床应用。一名72岁女性因右上和右下后牙修复体不美观前来我院就诊。口腔内检查发现金属冠边缘贴合不良。拆除不良修复体，并提供临时修复体以稳定下颌位置。使用口腔扫描仪记录光学印模和上下颌关系，并利用CAD/CAM技术制作整体式氧化锆全冠进行修复治疗。咬合检查显示，在放置氧化锆冠后，初始检查时的咬合力分布（右侧：33.5%，左侧：66.5%）得到改善（右侧：54.9%，左侧：45.1%）。咬合力和咬合力分布面积也呈上升趋势。口腔健康影响程度量表简表（OHIP - 14）评分从初始检查时的7分降至修复治疗后的0分。恰当的诊断和治疗计划有助于提高咬合力并使咬合力分布平衡。因此，本病例表明整体式氧化锆冠在实现美观和稳定的功能效果方面具有潜力。