Prajapati Paranjay, Sethuraman Rajesh, Naveen Y G, Patel Jayanti
Department of Prosthodontics, Crown and Bridge and Oral Implantology, K. M. Shah Dental College and Hospital, Sumandeep Vidyapeeth, Vadodara, Gujarat, India.
Contemp Clin Dent. 2013 Apr;4(2):162-9. doi: 10.4103/0976-237X.114859.
For mounting the maxillary cast to articulator, minimum three reference points not on single line, decide the plane to which maxillary cast is mounted. Variations exist in condylar guidance when different anterior reference points are used to mount the cast. Type of articulator may have influence on condylar guidance. A clinical study was planned to evaluate the effects of different anterior points of reference and two different articulator systems on condylar guidance.
Total 15 subjects were selected. Six sets of maxillary casts were obtained. Face bow record was made using orbitale as anterior point of reference and the record was transferred to the Arcon and Non-Arcon articulator. The second and third mounting on Arcon and Non-Arcon articulator were done using Superior and inferior annular groove on incisal pin of articulator. Protrusive interocclusal records were made for all the subjects. Two lateral cephalograms one in maximum intercuspation and the other in protrusion for left and right side were taken. Anatomic condylar guidance of the subject were obtained from radiograph tracing. Arcon and Non-arcon articulator were programmed with Protrusive interocclusal record of the subjects and the condylar guidance was tabulated for right and left side. The procedure was repeated for all three mountings for both the articulators.
The orbitale is the best reference point which mounts maxillary cast closer to anatomic position. Inferior annular groove can also be used as anterior point of the reference. The superior annular groove is not recommended anterior point of reference.
为了将上颌模型安装到牙合架上,至少需要三个不在同一直线上的参考点来确定上颌模型所安装的平面。当使用不同的前参考点来安装模型时,髁导存在差异。牙合架的类型可能会对髁导产生影响。计划进行一项临床研究,以评估不同前参考点和两种不同牙合架系统对髁导的影响。
共选取15名受试者。获取六套上颌模型。以眶点作为前参考点进行面弓记录,并将记录转移到Arcon和Non-Arcon牙合架上。在Arcon和Non-Arcon牙合架上的第二次和第三次安装使用牙合架切针上的上下环形凹槽。为所有受试者制作前伸牙合记录。拍摄左右两侧在最大牙尖交错位和前伸位的两张侧位头影测量片。从X线片描迹中获取受试者的解剖髁导。根据受试者的前伸牙合记录对Arcon和Non-arcon牙合架进行编程,并将左右两侧的髁导制成表格。对两种牙合架的所有三次安装重复该过程。
眶点是将上颌模型安装得更接近解剖位置的最佳参考点。下环形凹槽也可作为前参考点。不建议将上环形凹槽作为前参考点。