A Preliminary Study On Occlusal Vertical Rising In Incisor Caused By Occlusal Interference On Post Teeth

Objective:To study the occlusal vertical rising in incisor caused by occlusal interference on post teeth, explore the correlation of the occlusal vertical rising and occlusal interference,and analyze the effect of inclination of condylar path and height on the occlusal vertical rising in order to guide occlusion adjustment exactly and quickly in clinical practice. Methods: The occlusal interferences in height1mm,1.5mm,2.0m,2.5mm were made respectively on the mandibular second premolar,mandibular first molar and mandibular second molar in complete dentures.The occlusal vertical rising dimension under the different inclination of condylar path, bite high height and the distance from front teeth were measured and the relationships among the occlusal vertical rising dimension, the condylar path and the distance from front teeth were analyzed. Then the mathematical relationships between occlusal interferences on post teeth and the occlusal vertical rising dimensions in incisor were deduced. Results:(1) The same heights of occlusal interferences in different ICOP caused different occlusal vertical rising in mandibular incisor occlusal vertical rising with ICOP of0°,15°,30°,45°,60°obviously higher than that of IOCP of-15°and the difference was statistically significant (P <0.05); Different heights of occlusal interferences in the same ICOP caused different occlusal vertical rising in incisor.As the height decreased,occlusal vertical rising was declining and the differences were statistically significant (P <0.05). With the position of occlusal interferences changed from front to back in the same height of occlusal interferences and ICOP, the occlusal vertical rising in turn increased and the difference was statistically significant.(P<0.05).(2)There was a positive correlation between the height of occlusal interference on the posterior teeth and the occlusal vertical rising,with the correlation coefficient0.8943,0.9865,0.9930respectively from the second premolar, first molar and second molar.(3) Relational expression:Conclusions:within this research (1)Apart from IOCP of-15°,the inclination of condylar path has no significant effect on the occlusal vertical rising in incisor caused by occlusal interference on post teeth.(2)There is positive correlation between the occlusal vertical rising in incisor caused by height and distance to the incisor of occlusal interference on post teeth.(3) The occlusal vertical rising in incisor caused by occlusal interference on post teeth are related to other factors such as the distance of condylar point to the incisor point, the angle between the line of condylar point to incisor point and the occlusal plane,and the position of occlusal interference.