Occlusal rehabilitation is an effective means of treating tooth wear, edentulous jaws and other oral diseases. Among them, full-mouth fixed occlusal reconstruction can effectively restore aesthetics and function, but the complexity of the clinical process, the high sensitivity of the technique, and the high incidence of various complications have always drawn much attention. With the application and development of digital technology in occlusal rehabilitation, the treatment outcome has been improved compared with traditional treatment. However, there are many kinds of digital technology with different efficacy, how to build an efficiently standardized digital clinical technical solution is a current difficulty. Therefore, combined with the long-term work of the department of prosthodontics in our hospital, in this paper, the minimum (occlusal perception of thickness) and maximum (centric relation) geometric quantities which should be paid attention to during reconstruction are put forward. We systematically organized the clinical procedure of digital full-mouth fixed occlusal rehabilitation used in our department for a long time. In conclusion, a 5-stage 19-step or n-step solution (5-19N for short) characterized by "from large to small" restorative space splitting logic is proposed. It has a certain reference value for the future use of digital technology to deal with complex occlusal rehabilitation cases.
Humans ; Dental Occlusion ; Computer-Aided Design ; Mouth, Edentulous/rehabilitation*

Centric relation(CR)was used in the complete dentures for edentulous jaws firstly.Then,CR was gradual-ly applied in the clinical diagnosis and treatment of dentate jaws.Regarding the application of CR in dentate jaws,there are many doubts about its rationality.For instance,should CR be the core of diagnosis and treatment of temporomandibu-lar disorders?Should CR be used as the jaw position of establishing occlusion in occlusal reconstruction?Should CR serve as the target jaw position in orthodontic treatment?Meanwhile,varieties of CR clinical applications are objective.According to the existing evidence,this paper summarizes the applicable conditions of several main clinical situations with little controversy.We preliminarily put forward the decision tree for the clinical application of CR,which can be used as a reference in clinical practice.

Objective: To compare the hyoid bone position among patients with different sagittal skeletal malocclusions to provide a reference for clinicians to formulate treatment plans. Methods: Lateral cephalograms of 284 orthodontic patients were selected. According to ANB angles, the types of skeletal malocclusion of patients were determined as follows: Class Ⅰ (1° ≤ ANB ≤ 5°), Class Ⅱ (ANB>5°) and Class Ⅲ (ANB<1°). Ten parameters were used to determine hyoid positions. After comparing the hyoid positions of the three groups, stratified analyses based on sex and age were conducted. Results : No significant differences in demographic and vertical facial type features among skeletal Classes Ⅰ, Ⅱ and Ⅲ patients were observed (P>0.05). The angle between the Gonion-hyoid point line and the hyoid point-Menton line (Go-Hy-Me) of Class Ⅱ patients was significantly smaller than that of Class Ⅰ patients, and the angle between the most anterior and inferior point of the third cervical vertebra-hyoid point line and the hyoid point-Sella line (C3-Hy-S) of Class Ⅲ patients was smaller than that of Class I patients (P<0.05). Age-stratified analysis showed that in the juvenile group, the C3-Hy-S of Class Ⅲ patients was significantly smaller than that of Class Ⅰ patients in males and females (P<0.05). In the adult female group, the Go-Hy-Me of Class Ⅱ patients was significantly smaller, and the distance from the hyoid point to the mandibular plane (Hy-MP) was larger than that noted in Class Ⅰ patients (P<0.05); no significant difference in hyoid position between male Class Ⅱ and I patients was observed (P>0.05). Conclusions Compared with Class Ⅰ patients, the hyoid bone of Class Ⅱ patients in adult females was farther away from the mandible and that of Class Ⅲ patients in juveniles was farther away from the cervical vertebra and posterior cranial base.