• Journal of Oral Medicine and Pain
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• 제40권3호
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• pp.115-123
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• 2015

Purpose: The aim of this study was to elucidate the coordination patterns of the sternocleidomastoid and posterior cervical muscles in response to symmetrical and asymmetrical jaw functions in normal adults. Methods: Twenty-seven healthy volunteers (8 females, 19 males; mean age, $30.4{\pm}2.5$ years) participated in this study. Surface electromyography (EMG) was used to record activities in the masseter, suprahyoid, sternocleidomastoid, and posterior cervical muscles at rest and during maximum tooth clenching, biting of a cotton roll with the anterior teeth, unilateral biting of a cotton roll with the posterior teeth, bilateral biting of cotton rolls with the posterior teeth, and jaw opening while seated. Normalized amplitude, activity indices, and asymmetry indices were compared between the muscles and the jaw tasks. Results: During symmetrical jaw functions (e.g., tooth clenching, biting with the anterior teeth, bilateral biting with the posterior teeth, jaw opening), the sternocleidomastoid and posterior cervical muscles showed elevated EMG amplitudes compared with the resting condition. The co-activation pattern of the sternocleidomastoid muscle was more pronounced than those of the posterior cervical muscles during these tasks. During asymmetrical jaw functions (e.g., unilateral biting with the posterior teeth), the ipsilateral sternocleidomastoid and masseter muscles showed higher contraction activity than did the contralateral muscles, but the contralateral posterior cervical muscles were more active than the ipsilateral muscles. Conclusions: The sternocleidomastoid and posterior cervical muscles were shown to be co-activated and coordinated anteroposteriorly or bilaterally according to symmetrical or asymmetrical jaw function. These results suggest an integrated neural control mechanism for the jaw and neck muscles, and provide further evidence supporting the intimate functional coupling between the trigeminal and cervical neuromuscular systems.

• 대한통합의학회지
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• 제8권3호
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• pp.93-101
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• 2020

Purpose : Temporomandibular joint disorder (TMJD) is often accompanied by pain and limited range of motion of the jaw joint, which affect patients' quality of life and result in hypertrophy or hyperactivity of the muscles around the jaw joint. In this study, we compared the muscle thickness and tone of the masseter and sternocleidomastoid (SCM) muscles and the jaw range of motion in individuals with and without TMJD. Correlation comparison was performed on the results of the TMJD group. Methods : This study included 40 patients; 20 patients were assigned to an experimental group (TMJD group) and 20 to a control group (non-TMJD group). Ultrasonography, myotonometry, and measurements performed with digital Vernier calipers were used to determine the changes in muscle thickness, muscle tone, and maximum jaw opening, respectively. The independent t-test was used for intergroup comparison of data, and Pearson correlation coefficients were used to compare correlations in the TMJD group results. Results : We observed a significant intergroup difference in the masseter and SCM thickness during the relaxed and clenched phases (p<.05). A significant intergroup difference was also observed in maximum jaw opening (p<.05). With regard to muscle tone, we observed a significant intergroup difference in frequency (p=.011) and stiffness (p=.011) of the masseter, as well as in the frequency (p=.009) and stiffness (p=.026) of the SCM. We observed a moderate negative correlation (r=-.524) between maximum jaw opening and the frequency of the masseter. Additionally, we observed a moderately negative correlation between jaw opening and muscle stiffness (r=-.321). Conclusion : Planning exercise programs to treat patients with TMJD who present with pain should focus on efforts to reduce muscle thickness and achieve muscle relaxation (to reduce muscle tension) for improved jaw range of motion.

• Journal of Multimedia Information System
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• 제6권2호
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• pp.67-74
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• 2019

Bone density is one of the factors in the early failure of dental implants and doctors should make a preoperative assessment of jaw bone density using patient's CT data before dental implant surgery in order to find out whether the patient has osteoporosis and osteopenia. The main goal of this study was to propose a method that based on image processing techniques in order to provide accurate information about where to drill and place an abutment screw of implants in the jaw bone for doctors and reduce human activity for the estimation of the local cancellous bone density of mandible using CT data. The experiment was performed on a computed tomography data of the jaw bone of two different individuals. We assumed that the result of the estimation of jaw bone density depends on the angle of drilling and average HU (Hounsfield Unit) values were used to evaluate the quality of local cancellous bone density of mandible. As a result of this study, we have been developed a toolbox that can be used to estimate jaw bone density automatically and found a positive correlation between the angle of the drill and time complexity but a negative correlation between the diameter of the drill and time complexity.

• 대한치과의사협회지
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• 제49권7호
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• pp.372-377
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• 2011

Bisphosphonates are widely used in the management of osteoporosis patients. Many reports and clinical studies have published a relationship between necrotic bone lesions localized to the jaw and the use of chronic bisphosphonate therapy. This osteonecrosis named bisphosphonate-related osteonecrosis of the jaw(BRONJ). This article described the mechanism, chemical structure, indication, risk factor of the bisphosphonate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권6호
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• pp.360-364
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• 2023

Xanthogranulomatous inflammation (XGI) is an uncommon type of chronic inflammation and is histologically characterized by foamy histiocytes and giant cells. The most common sites of occurrence are kidneys and gallbladder. The etiology remains controversial. Involvement of the lower jaw bone is rare. In this study, we report a case of XGI presenting in the lower jaw.

• 대한치과교정학회지
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• 제35권3호
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• pp.238-249
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• 2005

악골부조화가 심할수록 기능향상을 위해 악골 및 치아 치조부에서의 보상반응이 현저해진다. 대표적인 현상으로 하악과두의 변위와 상악교합평면의 변화 등을 들 수 있다. 이러한 상하악골에서의 적응성 변화는 안모의 심미성과 교합의 기능 향상을 위해, 술후 안정성을 높이기 위해서 악교정수술을 통해 반드시 수정해야 할 요소이다 적절한 상악골 수술을 위해서 통상적으로 model surgery를 시행하여 왔으나 이의 단점을 보완하기 위해 Surgical Jaw Relator를 고안하였으며 이는 교합기의 mounting plate 대신에 부착함으로써 상하악 모형의 삼차원적 이동과 회전이 가능하도록 설계되어 있으며 기존의 모든 종류(Panadent. Sam, Denar, Hanau 등)의 교합기에 손쉽게 부착하여 수술용 스프린트의 제작 시간을 대폭 줄일 수 있는 장점이 있다 상악골 상방 이동이 필요한 하악전돌 증례와 상악골 하방 이동이 요구되는 하악후퇴 증례 등에 본 기구를 적용한 결과 양호한 수술 결과를 얻었으며, 이로써 정교한 상악 수술을 요하거나 명확한 수술 계획이 설정된 증례 등에서 본 기구를 적절하게 사용할 경우 수술용 스프린트를 효율적으로 제작하는데 다소 도움이 될 것으로 생각된다.

• 한국치위생학회지
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• 제12권6호
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• pp.1232-1240
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• 2012

Objectives : In this study, the treatment method for some college students, due to the misuse of non-therapeutic molding technique non-therapeutic procedure is applied in orthodontics or jaw surgery and therapeutic purposes, such as to properly recognize and to investigate whether. Methods : In this study used, 4 questions, the questionnaire general characteristics (such as gender, major, whether the treatment experience and purpose) Orthodontic and knowledge about the jaw surgery (Corrective jaw surgery hope and reason, or jaw surgery benefits, side effects, etc.) 6 items, calibration and recognition jaw surgery on seven items 17 items was constructed. Results : Of the perception of the majors of the respondents according to the presence or absence of a non-therapeutic procedure for calibration or jaw surgery the correct way, and the purpose appeared to know roughly majors and all students majoring statistically significant (p<.001). The degree of recognition for non-therapeutic procedures according to the gender of the respondents' facial aesthetic improvement, and the most common reason, you want to make a non-therapeutic procedure, correction or contrast, I've found that looks supremacist influence on the non-therapeutic procedure or roughly know the correct way, and jaw surgery for the purpose that appeared to be statistically significant (p<.05). Conclusions : Non-therapeutic procedure for the interest and knowledge to promote oral health as well as esthetic improvements to the original non-therapeutic procedure for therapeutic purposes and how to deliver education and it is very important.

• 구강회복응용과학지
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• 제23권2호
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• pp.171-178
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• 2007

Botulinum toxin type A (BTX-A) has a local effect at the neuromuscular junction by blocking acetylcholine release and thus causing paralysis and atrophy of the affected muscles. In dentistry, Botulinum toxin type A(BTX-A) is used for the treatment of masseteric hypertrophy, temporomandibular disorder, and severe bruxism related neurologic disorder. We hypothesized that the muscle atrophy after BTX-A injection into masseter muscle in growing rats, could affect the jaw growth. The purpose of this study was to determine the effects of the BTX-A injected into the masseter muscle on the jaw growth in rats. Rats were divided into four groups(group 1; control group, group 2; saline injection group, group 3; BTX-A injection group, group 4; baseline control group). Group 4 was sacrificed at the beginning of the experiment to provide baseline values of jaw measurements. The weight, length and width of jaw in those groups were measured every weeks. This study reported that the mandibular body length, condylar length, coronoid process length, anterior region height, coronoid process height and condylar height of the jaw in BTX-A injection group were shorter than those of the control and saline injection groups(P<0.05). In conclusion, BTX-A injected into the masseter muscle may affect the undergrowth of the jaw in rats.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.11.1-11.8
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• 2020

Background: The purpose of this study is to compare the skeletal stability of two-jaw surgery via surgery-first approach with conventional two-jaw surgery in facial asymmetry patients by measuring the skeletal changes after surgery from a three-dimensional analysis. From January 2010 to January 2014, 40 patients with facial asymmetry who underwent two-jaw surgery in Pusan National University Hospital were included in this study. They were classified into experimental group (n = 20) who underwent two-jaw surgery via surgery-first approach and control group (n = 20) who underwent conventional two-jaw surgery. After selection of 24 landmarks and the construction of horizontal and sagittal, coronal reference planes, changes in 10 linear measurements and 2 angular measurements were compared between the surgery-first approach and conventional groups in the preoperative, immediate postoperative, and postoperative periods. The paired t test and Student t test were used for statistical analysis. The mean and standard deviation of the measurement were calculated for the experimental and control groups. Results: The statistical analysis showed that changes in skeletal measurements were similar between the surgery-first approach and conventional groups, according to each period. However, U1-SRP measurement showed statistically significant changes in surgery-first approach groups at postsurgical change (T1 to T2). Also, the mean treatment duration in the treatment group was 15.9 ± 5.48 months whereas that in the control group was 32.9 ± 14.05 months. Conclusion: In facial asymmetry patients, similar results were observed in the postoperative skeletal stability when 2-jaw surgery via surgery-first approach was compared with conventional 2-jaw surgery. However, significant lateral deviation of upper incisor midline was observed. In addition, a shorter average treatment duration was observed. To stabilize the unstable occlusion after surgery, increased wearing of the stent and proactive rubber guidance will be needed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.245-246
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• 2010