• PNF and Movement
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• v.18 no.3
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• pp.333-341
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• 2020

Purpose: The purpose of this study was to investigate the effect of open and closed kinetic chain exercises with a sling on neck flexor thickness during chin-in movement in office workers with forward head posture. Methods: Thirty-one selected subjects randomly performed chin-in movement in open kinetic chain and closed kinetic chain exercises using a sling. All subjects were measured for their neck flexor thickness using ultrasound measurement equipment during the performance of chin-in movement in open and closed kinetic chain exercised. A paired t-test was used to compare the thickness of the total neck flexor, superficial, and deep neck flexor, respectively, between open and closed kinetic chain exercises with chin-in movement. Results: The thickness of the superficial neck flexor diminished in size more greatly during the chin-in movement with the closed kinetic chain than the open kinetic chain, but this was not a statistically significant difference (p > 0.05). On the other hand, the thickness of the total neck flexor and deep neck flexor had more greatly increased during the chin-in movement with the closed kinetic chain than the open kinetic chain, and this was a statistically significant differences (p < 0.05). Conclusion: This study suggested that chin-in movement with a closed kinetic chain is more effective in activating the deep neck flexor than the open kinetic chain. Thus, we believe that the closed kinetic chain exercise using a sling is an effective intervention to correct the postural alignment of individuals with forward head posture.

• The Journal of the Korean dental association
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• v.25 no.9 s.220
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• pp.847-854
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• 1987

Genioplasty may considerably change a person's face which needs surgical correction of deformed chin. Comprehensive treatment planning is therefore decisive for the treatment to be successful. A three-dimensional analysis of chin relative to cranial base, upper and lower jaws using the frontal and lateral facial photographs and cephalographs permits classification of the defective chin position and provides a basis for operation planning and deciding upon the operation method. A chin miniplate system has been developed for intraoperative registration securing the sagittal, vertical and horizontal position of the osteotomized chin and ould reduce the relapse rate.

• The korean journal of orthodontics
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• v.43 no.4
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• pp.168-177
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• 2013

Objective: In this study, we aimed to examine the relationship between chin deviation and the positional and morphological features of the mandible and to determine the factors that contributed to chin deviation in individuals with a unilateral cleft lip and palate (UCLP). Methods: Cone-beam computed tomography (CBCT) images of 28 adults with UCLP were analyzed in this study. Segmented three-dimensional temporomandibular fossa and mandible images were reconstructed, and angular, linear, and volumetric parameters were measured. Results: For all 28 individuals, the chin was found to deviate to the cleft side by 1.59 mm. Moreover, among these 28 individuals, only 7 showed distinct (more than 4 mm) chin deviation, which was toward the cleft side. Compared to the non-cleft side, the mandibular body length, frontal ramal inclination, and vertical position of the condyle were lower and inclination of the temporomandibular fossa was steeper on the cleft side. Furthermore, the differences in inclination of the temporomandibular fossa, mandibular body length, ramus length, and condylar volume ratio (non-deviated/deviated) were positively correlated with chin deviation. Conclusions: UCLP individuals show mild chin deviation to the cleft side. Statistical differences were noted in the parameters that represented positional and morphological asymmetries of the mandible and temporomandibular fossa; however, these differences were too small to indicate clinical significance.

• Journal of Oral Medicine and Pain
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• v.36 no.4
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• pp.253-259
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• 2011

Numb chin syndrome, is a rare neuropathy, characterized by facial and oral numbness restricted to the distribution of the mental nerve. Even though this neuropathy is uncommon, but this still has an important clinical meaning because it can be related with a malignancy. Because orofacial symptoms can even present the first clinical feature of a malignancy, dentists should pay careful attention to their meaning and importance to detect the malignant tumor early. Moreover, patients who present with a sudden numbness on chin should be investigated for the undiagnosed malignancy. In this report, we described a patient with stabbing orofacial pain and numbness of chin who was diagnosed with diffuse large B-cell lymphoma and placed the importance on the diagnosis of NCS.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.2
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• pp.199-202
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• 1991

Chin is located on most prominent portion of the face, so make more important esthetic value in impression. So historicaly, many authors had made efforts on correction of deformed chin, termed genioplasty. But those technique have been performed on limited cases, which have normal shape or width of chin. In the cases with more narrow or short chin, location of mental foramen or root of incisors restrict the use of such technique. But modified genioplasty technique we used can be performed without any restriction and change of frontal profile of chin. So we report a case that was performed with modified horizontal step osteotomy for advancement genioplasty, which had been reported by Hinds and Kent, with some complications.

• PNF and Movement
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• v.18 no.3
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• pp.403-414
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• 2020

Purpose: This study examined how performing chin tuck exercises in supine, sitting, and standing positions affects changes in the muscle activity of the neck and shoulder. Methods: Seventeen men and three women with forward head posture participated in the study. The subjects performed the chin tuck exercise using a pressure biofeedback unit. After determining the ideal order for performing the chin tuck exercise in supine, sitting, and standing positions through randomized controlled trials, muscle activity was measured in the dominant-side sternocleidomastoid, scalenus anterior, upper trapezius, and levator scapulae. Muscle activity was measured three times in each muscle for each position, and the average of the three measurements was used for analysis. Results: In this study, the chin tuck exercise performed in a supine position reduced muscle activity of the sternocleidomastoid, scalenus anterior, upper trapezius, and levator scapulae significantly more than performing the exercise in either sitting or standing positions (p < 0.05). No significant difference in muscle activity was observed when the exercise was performed in a sitting position versus a standing position (p < 0.05). Conclusion: Performing a chin tuck exercise in a supine position is more effective for stabilizing the neck and shoulder than performing it in a sitting or standing position, as it reduces excessive tension and fatigue in the neck and shoulder.

• Tuberculosis and Respiratory Diseases
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• v.53 no.1
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• pp.46-51
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• 2002

Numb chin syndrome is a rare clinical manifestation, characterized by focal sensory loss and paresthesia of the chin. It is more often associated with cancer than with benign disorders, and can be the first manifestation of a cancer. A 60-year-old man presented with focal numbness of right chin and gingiva for 10 days. Chest computed tomograghy showed a 3 cm sized mass on the distal left main- stem bronchus. Squamous cell carcinoma was diagnosed on bronchoscopic biopsy. However, bony metastasis of mandible was not evident on reontgenogram, CT scan, bone scintigram and positron emission tomography. Despite the chemotherapy with three cycles of paclitaxel and cisplatinum, the cancer was progressed and pain on the right chin was developed 4 months later. Bone scintigram showed multiple bony metastasis including mandible. Here we report this case with a brief review of the appropriate literature.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.12 no.3
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• pp.49-56
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• 1990

Facial balance is the primary detevminant of good facial esthetics and is expressed externally by the shape of facial soft tissues. Balance of the facial skeleton is most important in prediction of orthognathic surgery, however, it is not alwags coincided to soft tissue balance because the soft tissue drapes overlying hard tissue varies in thickness and tones from case to case. So, soft tissue facial balance and esthetics also should always be considered in prediction of hard tissue changes preoperatively. The chin has a paramount importance in the overall appearance of the face and facial profile because it may express individual charactor or image. Therefore positional change of the chin must be considered in any cases as the last and important option to give an overall soft tissue balance. Two cases were referred from orthodontists only for anterior segmental of teortomuy of the chin. Pre-operative evaluation showed poor soft tissue chin profiles which were not coincided to hard tissue chin balance. We altered surgical plans to fulfill balancing soft tissue profile and then could improve overall esthetics after surgery.

• The korean journal of orthodontics
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• v.20 no.1
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• pp.135-156
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• 1990

This study was undertaken to investigate the difference of chin morphology and mandibular form in relation to different mandibular growth direction. The subject was divided into three group i.e., control group, vertical group, and horizontal group, according to the criteria of $Bj{\ddot{o}}rk$ sum, and each group was composed of 15 females and 15 males. Medial axis analysis in addition to the routine cephalometric analysis using P.I.A.S. (personal image analysing system) was carried out to find out the differences of mandibular morphology on each group. The results were as follows: 1. The area of symphysis was larger in horizontal growth group than that of vertical growth group. 2. Protruding chin area was also larger in horizontal growth group than that of vertical growth group. 3. There was a close correlationship between protruding chin area and other form of mandible. 4. Antegonial notch depth and ramus posterior contour depth was deeper in vertical growth group than in horizontal growth group, and antegonial notch depth was more influenced by anterior part of notch than posterior part of notch. 5. Mental medial axis and incisal medial axis length, in relation to corpus medial axis length was larger in vertical growth group than in horizontal growth group.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.2
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• pp.184-199
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• 1996

The challenges to achieve three dimensional facial proportionality and occusal stability in many patients with complex dentofacial deformity have been met by the development and use of the maxilla, mandible, and chin surgery techniques in combination with efficient orthodontic treatment. There is a clinical, biological, and biomechanical foundation for simultaneous surgical repositioning of the maxilla, mandible, and chin in a significant proportion of adult and adolescent patients. A combination of the surgical and orthodontic approach may provide increased treatment efficiencies and optimal esthetic results. Art and science to determine the treatment objectives, specifically, the desired soft tissue changes are firstly established by using the clinician's "esthetic sense" of the facial beauty and proportion aided to a few cephalometric guidelines. In this sense, the dependence on the clinician's "esthetic eye" by Dr. Bell is more important in analyzing the facial proportion than the satisfaction of rigid cephalometric norms. The purpose of this article was to elucidate the indication for simultaneous surgical repositioning of the maxilla, mandible, and chin, and to describe the clinical cephalometric analysis for orthognathic surgery. Representative 6 case reports were presented and discussed to illustrate the esthetic, orthodontic, and surgical treatment objectives with long-term follow-up.