Postgraduate student, Department of Prosthodontics, M R Ambedkar Dental College and Hospital, Bengaluru, Karnataka, India.
Professor, Department of Prosthodontics, M R Ambedkar Dental College and Hospital, Bengaluru, Karnataka, India.
J Prosthet Dent. 2021 May;125(5):753-757. doi: 10.1016/j.prosdent.2020.02.033. Epub 2020 May 15.
Programming semiadjustable and fully adjustable articulators involves time-consuming clinical steps which can be avoided if an accurate radiographic method can accurately determine the condylar guidance angles.
The purpose of this clinical study was to compare the sagittal condylar guidance in dentate individuals as determined by a clinical method, protrusive interocclusal record, and a radiographic method, cone beam computed tomography. If the methods show a correlation, then cone beam computed tomography can be used as a time-saving method of programming an articulator for patients requiring a cone beam computed tomography scan.
A total of 40 participants (20 men and 20 women) within the 20 to 40 years age group were enrolled according to the inclusion and exclusion criteria. Cone beam computed tomography scans were obtained, and by using an appropriate software program, the sagittal condylar guidance was measured for both sides. A protrusive interocclusal record was obtained by using polyvinyl siloxane material. The maxillary cast of each participant was mounted on a semiadjustable articulator with a facebow transfer, and the mandibular cast was mounted with a maximum intercuspal record. The protrusive record was then transferred to the articulator for programming.
The right and left sagittal condylar guidance values obtained from both the protrusive interocclusal record and cone beam computed tomography method were comparable, with no significant differences (P>.05). The difference in condylar inclination values for both sexes obtained from both methods for both sides were not statistically different (P>.05). With increasing age, condylar inclination values obtained from both methods tended to decrease. The values for sagittal condylar guidance obtained from both methods (protrusive interocclusal record and cone beam computed tomography) were comparable and correlated.
Cone beam computed tomography measurement involves stable bony landmarks and can be standardized, whereas clinical methods are time consuming and can provide inaccurate results because of the instability of the materials used to register the maxillomandibular relationship. Thus, cone beam computed tomography can be used to obtain the sagittal horizontal guidance for programming semiadjustable and fully adjustable articulators for patients requiring a cone beam computed tomography scan.
编程半可调式和全可调式牙合架需要耗费时间的临床步骤,如果能够通过一种准确的放射学方法准确确定髁导角,则可以避免这些步骤。
本临床研究的目的是比较有牙个体的矢状髁导通过临床方法、前伸牙合记录和放射学方法——锥形束 CT 的测量结果。如果这些方法具有相关性,则可以将锥形束 CT 用作需要进行锥形束 CT 扫描的患者编程牙合架的省时方法。
根据纳入和排除标准,共招募了 40 名年龄在 20 至 40 岁之间的参与者(20 名男性和 20 名女性)。获得锥形束 CT 扫描,并使用适当的软件程序测量双侧矢状髁导。使用聚硅氧烷材料获得前伸牙合记录。将每个参与者的上颌模型安装在带有面弓转移的半可调式牙合架上,并将下颌模型安装在最大牙尖交错位记录上。然后将前伸记录转移到牙合架上进行编程。
从前伸牙合记录和锥形束 CT 方法获得的右侧和左侧矢状髁导值相当,无显著差异(P>.05)。从两种方法获得的左右两侧两性的髁突倾斜值差异无统计学意义(P>.05)。随着年龄的增长,从两种方法获得的髁突倾斜值都有下降的趋势。从两种方法(前伸牙合记录和锥形束 CT)获得的矢状髁导值相当且具有相关性。
锥形束 CT 测量涉及稳定的骨性标志,可以标准化,而临床方法耗时且由于用于记录颌间关系的材料不稳定,可能会提供不准确的结果。因此,锥形束 CT 可用于获取需要进行锥形束 CT 扫描的患者的矢状水平引导,以编程半可调式和全可调式牙合架。