• Journal of Korea Multimedia Society
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• 제12권1호
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• pp.147-155
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• 2009

Occlusion force measuring and analysis is a diagnostic method of tooth dynamics through the related force analysis. In this paper, we design and implement a series of occlusion force measuring software and evaluate its utility as a base system for a new occlusion force measure and analysis system development. For the reason, we developed a group of tools to measure the normal and abnormal occlusion force. Firstly, we have visualized the occlusion force distribution with quantitative figures. The center of force (COF) variation was visualized the path of marker according to teeth dynamics and the distribution of occlusion forces in 14 tooth regions. Secondly, we have implemented a left and right tooth force balance measurement ratio tool to estimate a specific tooth region force. Furthermore, the measured occlusion force variation recorded in the software each 0.5 second. As the result of the physical examination by the accessed hardware of sensor sheet method, we confirmed the distribution and balance of forces effectively.

• Journal of Oral Medicine and Pain
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• 제14권1호
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• pp.81-88
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• 1989

저자는 정상 치열을 가지며 두개하악장애의 증상 및 병력이 없는 성인 21명을 대상으로 computerized occlusal analysis system인 T-Scan system을 이용하여 교합력에 따른 치아접촉수와 총치아접촉시간을 측정한 후 정량적인 분석을 시도하여 다음과 같은 결론을 얻었다. 1. 최대 측두근 전부 근활성도의 약 20%, 50%, 80% 수준의 교합력에서 치아접촉수의 평균은 각각 1.6개, 8.8개, 16.7개로 교합력이 증가할수록 유의하게 증가하였다. 2. 최대 측두근 전부 근활성도의 약 20%, 50%, 80% 수준의 교합력에서 치아당 치아접촉수이 평균은 대구치에서는 0.2, 1.4, 2.2 개였으며 소구치에서는 0.1, 0.5, 1.1개였고, 전치에서는 0.1, 0.2, 0.6개로 교합력이 증가함에 따라 유의하게 증가하였다. 3. 치아접촉분포로 구분된 대칭군과 비대칭군간의 총치아접촉시간에는 유의한 차이가 없었다.

• Journal of Dental Rehabilitation and Applied Science
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• 제38권4호
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• pp.204-212
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• 2022

Purpose: The aim of this study was to compare changes of bite force, occlusal contact area, and dynamic functional occlusion analysis after occlusal stabilization splint therapy during sleep for one month in a patient with bruxism. Materials and Methods: From October 2021 to July 2022, sleep bruxism of 30 patients who visited the Department of Oral Medicine at Yonsei University College of Dentistry Hospital were recruited. The participants were divided into two groups: using an occlusal stabilization splint during sleep (treatment; n = 15) and not using an occlusal stabilization splint (control; n = 15). Before using the occlusal stabilization splint and one month after, bite force, occlusal contact area and dynamic functional occlusion analysis (ratio of left/right bite forces, average bite forces, maximum bite forces, and maximum contact areas during lateral and anterior and posterior mandibular movements) were performed. Results: There was no difference in bite force and occlusal contact area between the treatment group using the occlusal stabilization splint and the control group not using the occlusal stabilization splint during sleep for one month. However, there were significant differences in the average bite force and maximum bite force in the lateral and anterior and posterior mandibular movements and the maximum contact areas in the anterior and posterior mandibular movements. Conclusion: The occlusal stabilization splint is helpful for sleep bruxism patients who lateral and anterior and posterior mandibular movements. In addition, further studies are needed a double-blind study with a large population.

• Journal of Dental Rehabilitation and Applied Science
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• 제29권1호
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• pp.59-68
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• 2013

The objective of this study was to analyze occlusal contact pattern of 33 young adult males with normal occlusion during lateral excursion using T-scan III system which can measure the dynamic occlusion. Occlusal contact patterns were examined and categorized in non-working side disclusion point(more functionally acceptable position) not canine-to-canine position. Disclusion time, occlusal force, and occlusal force distribution ratio of upper canine at disclusion point during lateral excursion movement was also measured and compared among the groups divided according to contact patterns. The results showed that group function was clearly more dominant than canine guidance and other occlusal contact patterns different with existing patterns were found. There were significantly difference between groups in variables of T-scan measurement. T-scan III system is effective tools to analyze and evaluate occlusal contact patterns, disclusion time, occlusal force, and occlusal force distribution ratio of upper canine at disclusion point.

• Journal of Dental Rehabilitation and Applied Science
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• 제32권1호
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• pp.1-7
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• 2016

Mastication is the process to help digestion by chewing or grinding food. Masticatory system consists of maxilla, mandible, temporomandibular joints, ligaments, dentitions, and musculatures. Assessing the bite force can be one of the methods to estimate the masticatory system. Bite force is influenced by facial morphology, age, sex, periodontal status, temporomandibular joint disorder and dental condition, and so forth. In general, higher maximum bite force is seen in those who have a square-shaped face and in male rather than female. In addition, bite force tends to be increased by age 20, maintained constantly until age 40 - 50, and then decreased. Periodontal disease is known as a causative factor for decreased bite force while temporomandibular disorder (TMD) remains controversial as to whether it affects the force. The status of teeth is considered as an important factor to determine the maximum bite force.

• The korean journal of orthodontics
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• 제25권4호
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• pp.487-495
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• 1995

This study was undertaken to compare each maximum biting force and to investigate its relationship with the facial skeketal form, number and position of tooth contact between anterior openbite and normal occlusion adults, using the T-scan system and the lateral cephalogram. The subjects of this study consisted of a group of 25 individuals with normal occlusion and another group of 14 with anterior openbite. The obtained results of this study were as follows : 1. The maximum biting force of anterior openbite adults was less than that of normal occlusion adults. 2. In anterior openbite adults, there were negative correlations between the maximum, biting force and SN/MP, FMA, PP/MP mesurement of lateral cephalogram. 3. In anterior openbite adults, as the mesial angulation of lower first molar against the occlusal plane increased, the more the biting force decreased. 4. In both groups, the greater the number of tooth contact, the more the biting force increased. 5. In both groups, the center of effort for anteroposterior occlusal contact was located on the first molar region.

• Journal of Dental Rehabilitation and Applied Science
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• 제32권1호
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• pp.47-59
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• 2016

Purpose: The aim of this study was to investigate the changes in occlusal force after loss of the lower first molar depending on the inclination and extrusion of the adjacent and opposing teeth by using a strain gauge. Materials and Methods: Anatomic teeth were used to reconstruct the normal dental arch with loss of the lower right first molar. A uniformly thick layer of silicone was applied to the root to mimic the periodontal ligament. Four stages of dies with varying degrees of inclination and extrusion of the adjacent and opposing teeth were constructed and attached to master model interchangeably by using a CAD/CAM fabricated customized die system. The strain gauges were attached to teeth and a universal testing machine was used to determine the changes in occlusal force. An independent t-test and one-way ANOVA were performed (${\alpha}=.05$). Results: While simulating chewing food, the upper first, second premolar and lower second molar showed greater occlusal force than before extraction. When the change of adjacent teeth's occlusal force with their progressive movement after molar loss was evaluated, the difference among four die models was significant and was in the decreasing aspect (P < 0.05). Conclusion: When the lower first molar was lost and the adjacent teeth did not move yet, the occlusal force in adjacent teeth was higher than that when the lower first molar still existed. In addition, the occlusal force in the upper premolars and lower second molar decreased significantly with the progressive movement of adjacent teeth.

• The Journal of Korean Academy of Prosthodontics
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• 제61권2호
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• pp.160-178
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• 2023

Diagnosis and analysis of occlusal relationships are important factors in prosthetic treatment. A thorough occlusion analysis and evaluation should be performed before treatment to restore a stable interocclusal relationship. Analysis and evaluation are essential during the treatment process and at regular follow-ups. Recently, with the development of dental equipment and digital processing methods, new quantitative analysis methods that can record the patient's occlusal relationship have been introduced. Among them, the T-Scan Novus (Tekscan Inc., S. Boston, MA, USA) displays the strength of the initial contact point and the occlusal contact point of the teeth using a pressure sensor. With this, occlusal contact time of the teeth, anteroposterior and left-right balance of occlusal force can be compared. The Dental prescale II (GC Co., Tokyo, Japan) scans the occlusal contact point using a pressure-sensing film and analyzes the density of the contact point. It can measure the distribution and strength of the occlusal force of the teeth in the most natural occlusion state. Based on this, appropriate prosthetic treatment (four-unit fixed partial denture, removable partial denture, complete denture, and complete oral restoration cases) was performed according to the area and extent of the patient's tooth loss. The patient's occlusion at the first visit, treatment stage, right after treatment, and regular follow-up were compared and evaluated using a quantitative method for appropriate occlusion analysis using T-Scan Novus and Dental prescale II. This report enhances the understanding of occlusion analysis during prosthetic restoration. The results satisfied both the clinician and patients in terms of function and aesthetics.

• Journal of the korean academy of Pediatric Dentistry
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• 제35권3호
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• pp.399-417
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• 2008

The aim of this study was to investigate the relationships between bite force, masseter muscle and craniofacial morphology. 141 individuals were included. Bite forces were measured with a bite force transducer(SKT 2004). The facial morphology of the samples was evaluated on the Lateral and PA cephalometric radiographs(Asahi CX-90 SP). Ultrasonographic images were obtained for 36 individuals(Logiq 500). General status of the subjects were also measured for investigating possible relationships. Their relationships were analyzed by means of t-test, Pearson's correlation coefficients and simple regression analysis. In conclusion, bite force of molar was significantly correlated with craniofacial morphology for males and females, but not to masseter muscles. The masseter muscle for males had a significant correlation with craniofacial morphology. The unexpected negative correlations between size of masseter muscle and maxillary width was revealed for males. One possible way to arrive at a plausible explanation for the correlation between masster muscle, bite force and craniofacial morphology of males were the deep layer of masseter muscle had a great influence on males and the superficial layer of masseter muscle had a great influence on females.

• Journal of Oral Medicine and Pain
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• 제31권4호
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• pp.347-354
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• 2006

Most patients suffering from TMD appear to have unsatisfactory masticatory function and compromised values of bite force. The purposes of this study were to investigate and compare bite force between affected and unaffected sides of patients with unilateral TMD and to evaluate its relation with duration of TMD. 42 patients with unilateral TMD, from Department of Oral Medicine, Dankook University Dental Hospital, were selected for this study. The ratio of men to women was 9:33 and their mean age of $27.2{\pm}10.4$ years. The bite forces were measured over both canines (for anterior bite force) and $1^{st}$ molars (for posterior bite force) using a bite force recorder while all the subjects were asked to clench successively for 3 seconds not until pain was felt. They were compared with those measured from bilateral TMD patients(N=6, M:F=1:5, mean age: $23.0{\pm}27.3$ years). The unilateral TMD patients were divided into time groups according to duration of TMD on the basis of 1 and 6 months, respectively. Paired and unpaired t-tests were used for statistical analysis. Unilateral TMD patients in this study showed that the affected sides had significantly lower bite force than the unaffected sides(force difference of about 7-8 kgf, p<0.05) while there was no significant sides difference in the bilateral patients. Nor did bite force on the affected sides reveal significant difference between unilateral and bilateral TMD patients. With regards to TMD duration, there was significant difference between the patients with TMD < 6 months and $\geq$ 6 months (p<0.05) while no significant difference existed between < 1 month and $\geq$ 1 month. The results of this study indicated that unilateral TMD patients can exhibit more reduced bite force on the affected sides compared with that on the unaffected sides and that bite force on the unaffected sides might be deteriorated more as longer did TMD last.