Abstract: Objective: To investigate the digital design and fabrication method for preformed resin crowns in deciduous incisors, and to evaluate their clinical suitability. Methods: The 3D data of the clinical crowns of four maxillary deciduous incisor teeth from a children's deciduous teeth teaching model were obtained using a dentition model scanner. Reverse engineering software Geomagic Wrap 2021 was utilized, with reference to Professor Wang Huiyun's measurement and statistical data on Chinese children's deciduous teeth. Based on the scanned 3D data of maxillary deciduous incisors, adjustments were made to size ratios and 3D shapes. A standard-sized digital model for pre-coronation of deciduous incisors was constructed, incorporating design parameters with incisal end thickness of 0.8mm and lip/palatine surface thicknesses of 0.3mm. Taking into account the size ratio relationship observed in commonly used transparent resin crowns for maxillary incisors in pediatric stomatology departments, digital models for preformed crowns were designed with three types and four positions (51, 52, 61, and 62). Temporary preformed resin crowns were then fabricated using five-axis CNC cutting technology and subjected to trial evaluations in clinical cases. Results: A digital design and fabrication method for preformed resin crowns in maxillary deciduous incisors across four tooth positions was successfully developed. Initial clinical application demonstrated that these preformed resin crowns met the appearance, coloration, and strength requirements necessary for dental pediatrics practice according to evaluations conducted by senior pediatric experts. Conclusion: The digitally designed and fabricated preformed resin crowns presented in this study exhibit superior anatomical shape restoration compared to traditional transparent resin crown fillings while also achieving better aesthetic outcomes.

Key words: deciduous incisors, preformed crowns, computer-aided design and manufacturing, CAD/CAM resin