Establishment And Clinical Evaluation Of A Full Digital Workflow Of Presurgical Nasoalveolar Molding For Infants With Cleft Lip And Palate

Objectives: The purpose of this study was to establish a full digital workflow of presurgical nasoalveolar molding(NAM)for infants with complete cleft lip and palate(CLP)based on digital technology,and to evaluate its effect on nose and maxillary alveolar bone.Methods:Thirty unilateral cleft lip and palate(UCLP)digital models and thirty bilateral cleft lip and palate(BCLP)digital models were obtained with an intraoral scanner(Trios,3Shape,Denmark),and compared with the corresponding plaster models.Paired t tests were used to evaluate measurement difference between the two kinds of models,and to evaluate the reproducibility of the intraoral scanned models.Based on the digital model acquired by intraoral scanning,the movement of each alveolar segment was accurately controlled in the virtual environment to reduce the gap of the alveolar cleft and achieve a normal alveolar arch,and the digital model of each decomposition step was completed by computer-aided-design(CAD);and the digital model of the appliance was designed based on the digital model of each treatment stage;3D pringing individualized NAM appliance,a full digital workflow of presurgical nasoalveolar molding for infants with cleft lip and palate was established,and to evaluate the accuracy of 3D pringing appliance.3d MDface system(3d MD,Inc,USA)was utilized to obtain the three-dimensional images of ten infants with UCLP pre-and post-full digital NAM treatment,soft tissue changes were evaluated quantitatively in the nasal area.Twenty infants with UCLP and fifteen infants with BCLP were treated by using full digital NAM appliances,digital models were acquired by intraoral scanning pre-and post-treatment.The maxillary alveolar morphology was measured and evaluated.Results: There was no statistical differences between the measurements of plaster models and the digital models(P>0.05).The repeatability measurements of digital model were favorable,and the Intraclass correlation coefficient(ICC)were all greater than 0.90.Standard deviation of 3D printing NAM appliance compared with the designed 3D model were 0.0544 mm in UCLP and 0.1924 mm in BCLP.Full digital NAM treatment resulted in a statistically significant improvements in nasal deviation of UCLP infants(P<0.01).Significant difference was found in columellar ratio,nostril height ratio,nostril width ratio,and columellar deviation pre-and post-full digital NAM treatment(P<0.001).There were significant differences in the measurement items of alveolar cleft width,alveolar midline deviation and sagittal length of alveolar bone pre-and post-the full digital NAM treatment(P < 0.05).The intertuberosity width increased slightly after treatment,but the difference was not statistically significant(P > 0.05).Conclusions: The digital model of infant with CLP acquired by intraoral scanning can replace the traditional plaster model in clinical and research.The full digital workflow of presurgical nasoalveolar molding for infants with cleft lip and palate established in this study can improve the accuracy and efficiency of diagnosis and treatment,reduce the risk of treatment,it can not only significantly improve the symmetry of the nose,lengthen the columella,mold the nasal cartilage and improve the appearance of the nose;it can also effectively correct the dislocated alveolar segment,narrow the alveolar cleft,and restore the normal arch form.