• Journal of Dental Rehabilitation and Applied Science
• /
• v.23 no.3
• /
• pp.187-195
• /
• 2007

Temporomandibular disorders have been defined as a collective term embracing a number of clinical problems that involve the temporomandibular joint, the masticatory muscles, and associated structures. Since Dr. James Costen has mentioned about the relationship between TMD and posterior bite collapse, there have been many controversies about the etiology and comorbidities of TMD. The purpose of this study was to investigate the relationship between TMD and hearing acuity in 158 volunteers with or without TMD symptoms. The subjects were examined clinically about TMJ sound, missing teeth, tinnitus, TMJ pain and masticatory muscle pain and the hearing acuity were measured by Audiometer(ITO AE-1000, Japan). The result of this study indicated that there was no significant differences between TMD symptoms and hearing acuity relatively.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.36 no.2
• /
• pp.80-87
• /
• 2020

Purpose: This study aims to measure the mandibular movement using JT-3D system and provide a range of mandibular movement that can serve as a good reference for diagnosing the temporomandibular disorder. Materials and Methods: This study was conducted in 60 young male and female adults. The maximum opening and closing movement was recorded using JT-3D system, and by regarding 5 times of repetitive movement as 1 cycle of movement, total 3 cycles of movement were recorded. During the maximum opening, vertical position of lower jaw, antero-posterior position, lateral deflection position, and maximum opening distance were recorded. To evaluate the reproducibility of JT-3D system, statistical analysis were conducted (α = 0.05). Results: During the maximum opening, the average value appeared at 31.56 mm vertically and 24.42 mm rearwardly, lateral deflection position 0.72 mm, and maximum opening distance 40.32 mm. There was no statistical significance in all measured values for three cycles of movement recorded with JT-3D system (P > 0.05). Conclusion: During the maximum opening, the average value appeared at 0.72 mm in lateral deflection position and the maximum opening distance at 40.32 mm, and the analysis on the maximum opening of lower jaw using JT-3D system showed sufficiently reproducible results.

• Korean Journal of Cognitive Science
• /
• v.16 no.4
• /
• pp.305-322
• /
• 2005

Watermarking is a widely employed method tn protecting copyright of a digital image, the owner's unique image is embedded into the original image. Strengthened level of watermark insertion would help enhance its resilience in the process of extraction even from various distortions of transformation on the image size or resolution. However, its level, at the same time, should be moderated enough not to reach human visibility. Finding a balance between these two is crucial in watermarking. For the algorithm for watermarking, the predefined strength of a watermark, computed from the physical difference between the original and embedded images, is applied to all images uniformal. The mean brightness or contrast of the surrounding images, other than the absolute brightness of an object, could affect human sensitivity for object detection. In the present study, we examined whether the detectability for watermark noise might be attired by image statistics: mean brightness and contrast of the image. As the first step to examine their effect, we made rune fundamental images with varied brightness and control of the original image. For each fundamental image, detectability for watermark noise was measured. The results showed that the strength ot watermark node for detection increased as tile brightness and contrast of the fundamental image were increased. We have fitted the data to a regression line which can be used to estimate the strength of watermark of a given image with a certain brightness and contrast. Although we need to take other required factors into consideration in directly applying this formula to actual watermarking algorithm, an adaptive watermarking algorithm could be built on this formula with image statistics, such as brightness and contrast.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.23 no.2
• /
• pp.315-322
• /
• 1993

To evaluate of the relationship between the TMJ disorder and the vertical mandibular asymmetry, the author analyzed the differences between condylar heights, ramus heights and mandibular heights of both sides. All measurements were performed with a digital micrometer on the panoramic radiographs of 36 TMJ disorder patients and 30 normal control group. The differences were expressed in millimeters and percentage using the following formula; ｜(R-L)/(R+L)｜×100% The results were as follows : 1. The condylar height difference was greater of in patient group (1.86±1.66㎜) than that of in control group (1.22±0.85㎜)(p<0.05). But there was no significant difference in the condylar height ratio difference between patient group (11.67㎜11.44%) and control group (7.64±621%) (p>0.05). 2. The ramus height difference and ramus height ratio difference of patient group (4.52±3.70㎜, 4.39±3.49%) were greater than those of control group (2.64±2.13㎜, 2.46±2.02%)(p<0.05, p<0.01). 3. The mandibular height difference and mandibular height ratio difference of patient group (4.32±3.52㎜, 3.59±2.81%) were greater than those of control group (2.57±2.46㎜, 2.01±1.95%) (p<0.05). 4. The ratio difference in condylar height to ramus height and condylar height to mandibular height of patient group (5.01±4.13%, 3.36±2.88%) were greater than those of control group (2.33±1.78%, 1.90±1.40%) (p<0.01).

• Journal of Korean Physical Therapy Science
• /
• v.7 no.2
• /
• pp.653-662
• /
• 2000

A single experimental design (alternating treatment design) was used to compare the effects of the mobilization and heat therapy on the pain and mouth opening in patient with temporo-mandibular disorder (TMD). In the mobilization sessions, the physiotherapist performed two methods of the mobilization on the temporo-mandibular joints. In the heat therapy sessions, the patient received infrared and ultrasono on the temporo-mandibular joint. The mobilization and heat therapy were performed on alternate days during 10 days. Pain was measured by visual analogue scale (VAS) and mouth opening was measured by caliper. The results showed that mobilization and heat therapy were effective in pain reduce and mouth opening increase, and mobilization was superior to heat therapy in mouth opening increase and pain reduce.

• Journal of Oral Medicine and Pain
• /
• v.36 no.4
• /
• pp.235-243
• /
• 2011

Personal characteristics of female lichen planus patients were analyzed psychologically using the SCL-90-R. The subjects were 51 female lichen planus patients who visited Orofacial pain clinic of the Department of Oral Medicine, Pusan National University Yangsan Dental Hospital from 2009 to 2010. The female control group were collected from Pusan Kyungnam area. 45 female burning mouth syndrome patients, 36 female temporomandibular joint disorder patients, 23 female trigeminal neuralgia patients were subjected at Orofacial pain clinic of the Department of Oral Medicine, Pusan National University Hospital from 1998 to 2010. 1. Lichen planus patients group, burning mouth syndrome patient group, temporomandibular joint disorder patients group, trigeminal neuralgia patients group and the control group were within normal range. 2. The T-Scores of O-C, IS, DEP, ANX, HOS, PHOB in lichen planus patients group were significantly higher than in the control group. 3. The T-Scores of O-C, IS, DEP, ANX, PAR, PSY in chronic group was significantly higher than in acute group. 4. The T-Scores of SOM, O-C, DEP, ANX, in burning mouth syndrome patients group was significantly higher than in lichen planus patient group. 5. There was no significant T-score difference between lichen planus group and temporomandibular joint disorder patient group. 6. There was no significant T-score difference between lichen planus group and trigeminal neuralgia patient group.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.26 no.2
• /
• pp.157-168
• /
• 2010

Many athletes have been using occlusal stabilization appliances to improve their performance. Few studies have examined the benefits of such an appliance in golf. We determined the effect of such appliances on the masticatory muscle activities and driving distances of professional golf players. The appliances were customized for each player and adjusted using a computerized device. The electromyographic muscle activities and driving distances with and without the appliance were measured and compared using the K7 Analyzer and the GolfAchiever II assembly. A paired t-test was used for statistical analysis. The muscle activities of the temporo-frontal and masseter muscles with the appliance were significantly more stable than those without the appliance, and the driving distances with the appliance were significantly different from those without it. Although there were intra-individual differences, professional golf players with temporomandibular disorders showed a greater improvement in performance.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.35 no.6
• /
• pp.403-410
• /
• 2009

Those composing temporomandibular joint (TMJ) complex such as the temporal bone, the disc and the mandibular condyle perform their own functions with organic relation. The retrodiscal tissue is the main area of pain induction and contributes to compositional change of synovial fluid. If displacement of the disc lasts long time, not only adaptive changes, but also destructive or degenerative changes may happen. It was reported that these changes and symptoms appear mostly to female rather than male and especially, in the case of patients suffering from TMJ disorder, a large quantity of female sex hormone is found in the joint synovium. And that may play a role in bone resorption and inflammation. Also, the frequency and the intensity of pain perception for female is reported to be much more than for male. In this study, we investigated the expression extents of estrogen receptors (ER) and progesteron receptors (PR) in retrodiscal tissue with immunohistochemistry among the patients received TMJ surgery and compared with MRI findings and surgical findings. We report the relations between the expression of ER in retrodiscal tissue and the pathological change in TMJ, such as inflammation, internal derangement and osteoarthritis.

• Journal of Oral Medicine and Pain
• /
• v.36 no.1
• /
• pp.71-79
• /
• 2011

Aim: Disc displacement without reduction of the temporomandibular joint (TMJ) has been managed by mandibular manipulation to reduce the displaced disc but with a low success rate. The purpose of this study was to determine whether auriculotemporal nerve block anesthesia had an effect on the reduction of the displaced disc and to analyze the factors that influenced the result. Methods: 112 patients were diagnosed with disc displacement without reduction and treated by mandibular manipulation. Disc was recaptured in 35 patients. Among the 77 patients with whom disc recapture had failed, the auriculotemporal nerve was blocked with a local anesthetic in the 49 patients (mean $age \;{\pm}\; SD\; =\; 34.4\;{\pm}\; 15.1$; male 24, female 25) and then mandibular manipulation was performed again. Factors including age, elapsed time from the onset, and opening amount were analyzed in association with disc reduction rate with the auriculotemporal nerve block. Results: Among 49 patients who did not respond to manipulation only, manual reduction with auriculotemporal nerve block anesthesia was successful in 19 patients (38.8%). Maximum unassisted opening amount significantly increased in the 19 patients with successful recapture of the disc ($mean \;{\pm}\; SD\; =\; 46.1 \;{\pm}\; 4.5\; mm$), in contrast to the limited opening amount of the 49 patients before local anesthesia of the auriculotemporal nerve ($mean \;{\pm}\; SD\; =\; 25.7 \;{\pm}\; 6.0\; mm$). Age, elapsed time after the onset, and preoperative opening amount were not associated with the reduction rate. Conclusion: The results of this study suggest that auriculotemporal nerve block anesthesia increases the reduction rate of the disc displacement without reduction of the TMJ when combined with mandibular manipulation, and such anesthesia should be applied at the first stage of manual treatment of disc displacement without reduction.

• Journal of Oral Medicine and Pain
• /
• v.37 no.1
• /
• pp.61-72
• /
• 2012

Temporomandibular disorder(TMD) is relatively prevalent disease, and quality of life may be impaired in TMD patients. Like general population, dental hospital workers are also exposed to the risk of TMD. But, many of them tend to overlook or tolerate their symptoms for lack of time and interest. Therefore, problems may become more serious, causing interference of performing task and decrease of quality of life. The aim of this study were to obtain data for TMD prevalence in dental hospital workers and to evaluate quality of life according to TMD symptoms. Subjects were recruited from Wonkwang University Dental Hospital. After consent, subjects completed quality of life questionnaire and were evaluated for subjective and objective signs and symptoms of TMD. Subjects were classified into 4 groups : (1) normal group (2) joint disorder group, (3) local myalgia group, and (4) myofascial pain group. The result of the study indicated that TMD negatively influences the quality of life in dental hospital worker. TMD symptoms can deteriorate quality of life in dental hospital worker. Future effort to make protocol for proper management is needed.