Constructing 3-dimensional colorized digital dental model assisted by digital photogra-phy / 北京大学学报(医学版)

ABSTRACT

Objective:To explore a method of constructing universal 3-dimensional (3D)colorized digital dental model which can be displayed and edited in common 3 D software (such as Geomagic se-ries),in order to improve the visual effect of digital dental model in 3D software.Methods:The mor-phological data of teeth and gingivae were obtained by intra-oral scanning system (3Shape TRIOS),con-structing 3D digital dental models.The 3D digital dental models were exported as STL files.Meanwhile, referring to the accredited photography guide of American Academy of Cosmetic Dentistry (AACD),five selected digital photographs of patients’teeth and gingivae were taken by digital single lens reflex camera (DSLR) with the same exposure parameters (except occlusal views ) to capture the color data.In Geomagic Studio 201 3,after STL file of 3D digital dental model being imported,digital photographs were projected on 3D digital dental model with corresponding position and angle.The junctions of different photos were carefully trimmed to get continuous and natural color transitions.Then the 3 D colorized digital dental model was constructed,which was exported as OBJ file or WRP file which was a special file for software of Geomagic series.For the purpose of evaluating the visual effect of the 3 D colorized digital model,a rating scale on color simulation effect in views of patients’evaluation was used.Sixteen patients were recruited and their scores on colored and non-colored digital dental models were recorded.The data were analyzed using McNemar-Bowker test in SPSS 20.Results:Universal 3D colorized digital dental model with better color simulation was constructed based on intra-oral scanning and digital photography. For clinical application,the 3D colorized digital dental models,combined with 3D face images,were in-troduced into 3D smile design of aesthetic rehabilitation,which could improve the patients’cognition for the esthetic digital design and virtual prosthetic effect.Conclusion:Universal 3 D colorized digital dental model with better color simulation can be constructed assisted by 3 D dental scanning system and digital photography.In clinical practice,the communication between dentist and patients could be improved as-sisted by the better visual perception since the colorized 3 D digital dental models with better color simula-tion effect.