Objective: To observe the changes of forward displacement of maxillary complete denture during centric occlusion, three different methods were used to record the changes of vertical overlap and the comfort level of patients before and after the selective grinding of the three dentures made according to maxillo-mandibular horizontal relationship record.
Methods: Twelve edentulous patients with normal stomatognathic system were recruited in this study. Three types of complete dentures for these 12 edentulous patients were made according to their different maxilla-mandibular horizontal relationship record methods. The amount of displacement of the maxillary complete denture, the vertical overlap of the anterior teeth as well as patient comfort level were recorded before and after selective grinding. Statistical analysis was performed using the SPSS 17.0 software package.
Results: Before selective grinding, the amount of displacement of denture A was significantly larger than those of dentures B and C (P<0.05). After selective grinding, there was no statistical difference among the three dentures (P>0.05). During selective grinding, the vertical overlap variation of denture A was significantly greater than those of dentures B and C (P<0.05). Before selective grinding, the comfort level of the denture A was the lowest (P<0.05), and no statistical difference was found between dentures B and C (P>0.05). After selective grinding, no statistical difference was found among the three dentures (P>0.05).
Conclusions: Among the complete dentures with anatomical teeth, the dentures whose horizontal relationship was recorded at 1 mm before the apex of the Gothic arch apex and with checkbite are more in line with clinical repair requirements. Complete dentures whose horizontal relationship was recorded at the apex of Gothic arch need to be adjusted with selective grinding to meet the clinical restoration requirements.
目的 通过观察3种方法确定水平颌位关系的全口义齿在选磨前及选磨后正中咬合时，上颌全口义齿近中移位的变化、前牙区覆牙合的变化及患者舒适度差异，探寻确定无牙颌水平颌位关系的最佳方法。方法 在适宜垂直距离条件下，对12例口颌系统基本正常的无牙颌患者同时制作由哥特式弓轨迹顶点、哥特式弓轨迹顶点前1 mm以及直接咬合法确定水平颌位关系的3副全口义齿（分别记作义齿A、B和C），记录每副全口义齿义齿选磨前及选磨后正中咬合时上颌全口义齿近中移位量、前牙区的覆牙合以及患者的舒适度，通过SPSS 17.0软件包对全口义齿近中移位量、前牙区的覆牙合变化量以及患者的舒适度进行统计学分析。结果 选磨前，义齿A的近中移位量最大，明显大于义齿B和义齿C（P<0.05），选磨后，三者之间的差异无统计学意义（P>0.05）。选磨前后义齿A的覆牙合变化量明显大于义齿B和义齿C（P<0.05）。选磨前，义齿A的舒适度最低（P<0.05），义齿B与C舒适度之间的差异无统计学意义（P>0.05）。选磨后，义齿A、B、C之间舒适度的差异无统计学意义（P>0.05）。结论 在解剖式牙排列的三维牙合全口义齿中，哥特式弓轨迹顶点前1 mm以及直接咬合法确定水平颌位关系的全口义齿是更符合临床的修复做法，哥特式弓轨迹顶点确定水平颌位关系的全口义齿需要配合调磨，都能达到临床的修复要求。.
Keywords: accuracy; comfort; complete denture; displacement; maxillo-mandibular horizontal relationship record; selective grinding.