• Journal of the Korean Academy of Esthetic Dentistry
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• v.32 no.1
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• pp.8-15
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• 2023

In case with severely atrophied mandibular ridges, it may be difficult to achieve adequate retention and stability of dentures through the normal functional impression process of complete dentures. In these patients, an approach using the neutral zone raising technique may be an effective alternative. The neutral zone is defined as the area where the pressure of the tongue towards the outside of the mouth and the pressure of the cheek and lips towards the inside are balanced during the normal oral function of the muscular-nervous system. Complete dentures made through neutral zone impression not only improve retention and stability, but also provide adequate tongue space in the posterior teeth area. Additionally, food residues are reduced in the area around artificial teeth, and aesthetics are improved through appropriate facial support.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.121-134
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• 2004

This article describes a clinical protocol for the conventional rehabilitation of patient diagnosed with partial anodontia. A combined dental therapy approach was used and included endodontic therapy and root capping on the maxillary central incisors, fabrication of a maxillary overdenture, and fabrication of mandibular konus overdenture supported by 3 konus abutments. Within this protocol, tooth-supported overdenture prostheses are used for 2 purposes: first, to obtain the most rigid retention and function at an established maxillary-mandibular relationship; and second, to continuously maintain function and esthetic appearance applying immediate dentures after teeth extraction. The idea behind this protocol and its associated clinical procedures is presented along with a discussion compared with implant therapy. In the case introduced, and after 7 years of observation, the therapy can be seen as a success. We increased the occlusal vertical height in this case, but it would be more appropriate to see this as recovering the occlusal vertical height that was lost. The process of increasing the occlusal vertical height, that is restoration of the face, modification of the extrinsic occlusion of the incisors, and retraction of the mandible is very difficult and important. Ultimately, class III malocclusion is fixed, adequate occlusal vertical height is gained, and the retracted posterior anodontial portion is restored by prosthodontic dentures based on the rigid support theory. The result of the therapy done on the later-achieved malocclusion with partial anodontia on the posterior portion must consider the following in order to maintain the safety of the esthetics of the tooth and face for a period of time: 1) occlusal restoration with an ideal occlusal vertical height, 2) allowance of the final occlusion induced by the functional relationship of the upper and lower jaw, 3)final occlusion functionally induced by the lip competence limit.

• Journal of Oral Medicine and Pain
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• v.30 no.1
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• pp.121-129
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• 2005

In this experiment, eleven volunteers were followed up for 15 months after the injection of botulinum toxin type A on right and left masseter muscles. The measurement of masseter muscle atrophy for each volunteer was performed by CT(computed tomography) three times: before the injection, three and fifteen months after the injection. The thickness and area of muscle were measured in three positions which are 10 (position 1), 20 (position 2), and 40 mm (position 3) above the inferior border of mandible(the injection site was nearest the position 1). The thickness of masster muscle was decreased in all three positions three months after the injection, but no significant change was observed fifteen months after the injection. On the other hand, the area of masster muscle was decreased in all three positions three months after the injection. Furthermore, the area was decreased significantly in positions 1 and 2, but not in position 3 fifteen months after the injection. As a result, toxin is still in effect even fifteen months after the injection. Finally, the present study shows that the measurement of muscle area provides more precise informations than that of muscle thickness does.

• Korean Journal of Animal Reproduction
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• v.23 no.1
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• pp.69-73
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• 1999

A calf with derodidymus was delivered from a 3-year old Korean-native cow with abortion last ime at Jangheong area in Chonnam Province. The anomaly with body weight of 35 kg was born t the normal time of parturition. During the parturition, however, the calf with twin head was onfirmed and the complete amputation between fore and hind limb was inevitably carried out or safety of the dam. The calf had normal skeleton and extremities but had two heads and cervical vertebrae divided from upper thoracic part. At necropsy, there were found totally 3 pairs of ore limbs including two pairs of hypoplastic ones hided in the thoracic limb and also found one air of sternum. One head had incomplete torsion or unilateral hypoplasia of mandible with artly hypoplastic skull. There were marked fusion and torsion from cervical to 3rd thoracic vertebra. No abnormality was found on all organs in the pleural and abdominal cavities except a rectal stricture formed at 5 cm away from the atresia ani.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.3
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• pp.266-275
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• 2008

Dental endosseous implants require sufficient alveolar bone volume and quality for complete bone coverage and initial stability. But, atrophy or resorption of alveolar bone height and width according to patient's age and period of tooth loss can prevent ideal implant placement. Bone graft procedure has been proposed before or simultaneously with the placement of dental implants in patients with insufficient alveolar bone volume. While allografts, xenografts, and alloplastic bone grafts have been proposed and studied for alveolar ridge augmentation, the use of autogenous bone grafts represents the 'gold standard' for bone augmentation procedures. Conventional bone grafts are usually harvested from distant sites such as the ilium or ribs. Recently there is a growing use of intraoral bone grafts from intraoral donor sites such as mandibular symphysis, mandibular ramus and maxillary tuberosity. We recommend that the mandibular ramus is a safe autogenous bone graft donor site for bone harvesting with low morbidity. We report various effective autogenous bone graft procedures from mandibular ramus for the implant placement on various atrophic alveolar ridges.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.2
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• pp.154-165
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• 2006

Objectives : It is difficult to place implants at a severely atrophied edentulous mandible because of vertical and horizontal alveolar defect. The autogenous and allogenic bone graft and guided bone regeneration are useful, but there are some limitations such as the resorption and infection of the grafted bone, and insufficiency of soft tissue. Distraction osteogenesis has recently evolved a challenging technique to overcome major draws of conventional augmentation procedures, we, therefore, report the four applications of implant placement after vertical alveolar distraction osteogenesis. Patients and Methods : Four patients(all female, mean age: $60{\pm}6$ years) with severe alveolar ridge deficiencies at their anterior mandible were treated with vertical alveolar distraction osteogenesis by intraoral device(Track 1.5, 15 mm model, KLS Martin, Tuttlingen, Germany) and placement of implants (Branemark MK III, TiUnite). After the latency periods of 5, 7, 8 days, distraction rhythm and rate were $0.5\;mm{\times}2\;times/day$ in the case of good bone quality, and $0.25\;mm{\times}3\;times/day$ in the case of poor bone quality. After consolidation periods of mean fifteen weeks, five implants for each patients were placed at the interforaminal area. Results : On average, a vertical gain of $11.38{\pm}1.38\;mm$ was obtained by distraction. And all distraction zone showed complete ossification by panoramic radiography. There were no postoperative complications other than numbness of lower lip in one case. Total twenty implants in four patients were placed and their outcomes were satisfactory. Conclusion : It is a useful method to place five implants after vertical distraction osteogenesis of the severely atrophied mandible for the implant-supported fixed prosthesis.