Evaluation and development of digital device for measuring proximal tooth contact tightness / 대한치과보철학회지

STATEMENT OF PROBLEM: The proper contact relation between adjacent teeth in each arch plays an important role in the stability and maintenance of the integrity of the dental arches. Proximal contact has been defined as the area of a tooth that is in close association, connection, or touch with an adjacent tooth in the same arch. PURPOSE: The aim of this study was to develop a digital device for measuring the proximal tooth contact tightness by pulling a thin stainless steel strip (2mm wide, 0.03mm thick) inserted between proximal tooth contact. MATERIAL AND METHOD: This device consists of measuring part, sensor part, motor part and body part. The stainless steel strip was connected to a stain gauge. The strain gauge was designed to convert the frictional force into a compressive force. This compressive force was detected as a electrical signal and the electrical signal was digitalized by a A/D converter. The digital signals were displayed by a micro-processor. The pulling speed was 8mm/s. RESULTS: For testing reliability of the device in vivo, two healthy young adults (A, B) participated in this experiment. The tightness of proximal tooth contact between the second premolar and the first molar of mandible (subject A) and maxilla (subject B) was measured fifteen times for three days at rest. We double-checked the accuracy of the device with a Universal Testing Machine. Output signals from the Universal Testing Machine and the measuring device were compared. Regression analysis showed high linearity between these two signals. In vivo test, no significant differences were found between measurements. CONCLUSION: This device has shown to be capable of producing reliable and reproducible results in measuring proximal tooth contact. Therefore, it was considered that this device was appropriate to apply clinically.

A study on the changes of tooth contacts following orthodontic treatment by use of the T-Scan system / 대한치과교정학회지

This study was undertaken to investigate the changes of tooth contacts following orthodontic treatment, using T-Scan system. Occlusal contacts in maximum intercuspation were examined in 26 patients at the end of the active phase of orthodontic treatment and again 3 months into the retention phase to assess the initial posttreatment occlusal changes. The obtained results of this study were as follows: 1. The mean total number of contacts increased from 11.27 at the end of orthodontic treatment to 13.15 at the follow up visit, which was found to be statistically significant (P0.05). 6. The number of post. teeth in contact significantly increased, which was statistically significant (P<0.05). 7. A statistically significant relationship was found between the total number of contacts at the end of treatment and the change in the contacts over time. The fewer the number of tooth contact was at the end of orthodontic treatment, the greater number of tooth contact increased over time(r=-0.38, P<0.05).