• 구강회복응용과학지
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• 제27권3호
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• pp.285-292
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• 2011

이번 연구는 전산화단층촬영법 (computed tomography)을 이용하여 상악동 측벽의 두께를 측정하고, 상악동 거상술을 위한 측벽창 (lateral wall window)형성 시 가장 적절한 수직적 위치를 평가하고자 한다. 상악동 거상술이 필요한 30명 환자의 전산화단층촬영 방사선영상을 대상으로 분석하였다. 상악동 측벽의 두께는 상악동 하연을 기준으로 수직적 위치에 따라 분류하고, 3회 반복 측정하여 평균을 구하였다. 상악동 측벽의 두께는 상악동 하연 (sinus inferior border, SIB)을 기준으로 상방 2 mm (SIB + 2) 까지는 2 mm 이상으로 관찰되었고, 상악동의 하연을 기준으로 3 mm 상방 (SIB + 3)에서는 2 mm 미만으로 나타났다. 이번 연구에서 근거하여 측방 접근법을 이용한 상악동 거상술에서 측벽창의 위치는 상악골의 하연을 기준으로 약 3 mm 상방에서 형성하는 것이 적절할 것으로 사료된다.

• 치과방사선
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• 제14권1호
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• pp.81-87
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• 1984

This study was performed to observe the secondary images and to analyse the relationships between the primary and secondary images in panoramic radiograph. Using the Moritta's Panex-EC panoramic x-ray machine and the human dry skull, the author analysed 17 radiographs which were selected from 65 radiographs of the dry skull that attached the radiopaque materials, and the attached regions of the radiopaque materials were the normal anatomical structures which were important and selected as a regions for the evaluation of the secondary images effectively. The results were as follows; 1. The cervical vertebrae showed three images. The midline image was the most distorted and less clear, and bilateral images were slightly superimposed over the posterior border of the mandibular ramus. 2. In mandible, the secondary image of the posterior border of the ramus was superimposed on the opposite ramus region, and this image was elongated from the anterior border of the ramus to the lateral side of the posterior border of the ramus. The secondary image of the condyle was observed on the upper area of the coronoid process, the sigmoid notch and the condyle in opposite side. 3. In maxilla, the posterior region of the hard palate showed the secondary image on the lower part of the nasal cavity and the medial wall of the maxillary sinus. 4. The primary images of the occipital condyle and the mastoid process appeared on the same region, and only the secondary image of the occipital condyle was observed symmetrically on the opposite side with similar shape to the primary one. 5. In the cranial base, the anatomical structures of the midsagittal portions like a inferior border of the frontal sinus, sella turcica, inferior borderr of the sphenoid sinus and inferior border of the posterior part of the occipital bone showed the simillar shape between the primary and secondary images symmetrically. 6. The petrous portion of the temporal bone showed the secondary image on the lateral side of the sella-turcica, and the secondary images of the posterior border of lesser wing, superior border of greater wing of the sphenoid bone and posterior border were observed on the anterior-superior and inferior region of the sella-turcica.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권6호
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• pp.513-517
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• 2008

Purpose: This study aimed to evaluate distribution and maximal value of mechanical stresses on the reconstruction plate, bridging mandibular symphysis defect, and to optimize the most appropriate locations of the plate to distribute the stress causing the fracture of the plate. Materials and methods: Four types of reconstruction were constructed by different number and location of the reconstruction plates on the 3 D finite element model (FEM) of a human edentulous mandible; Type I: one plate on the inferior border of the anterior mandible, Type II: one plate on the middle of the anterior mandible, Type III: one plate on the superior border of the anterior mandible, and Type IV: two plates on the inferior and superior border of the anterior mandible. Results: The results showed that the maximal stress of type I (234.29 Mpa) was lower than that of type II (260.91 Mpa) and type III (247.37 Mpa), but higher than that of type IV (186.64 Mpa). We could also observe that the stresses are tending to focus on the inner side and inferior part of the plate which connected proximal segment from the vertical load. Conclusions: On the basis of the findings, it was concluded that using a plate on the inferior border of mandible or two plates on the inferior and superior border of mandible are more favorable to distribute mechanical stresses, which could reduce the fracture of the plate.

• Imaging Science in Dentistry
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• 제36권2호
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• pp.81-88
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• 2006

Purpose : To review developmental salivary gland defect based on 12 reported cases and literature, and to guide radiographic diagnosis of this entity. Materials and Methods : The 12 cases of developmental salivary gland defect of Chosun University Dental Hospital in the last 4 years were analyzed and compared with previous reported cases. Result : 11 of the 12 cases were found in men, indicating a very strong male predilection. The peak age was in the 6th decade. These defects were situated just above or at the inferior border of mandible between the first molar and the mandibular angle, and always Inferior to the mandibular canal. Only one case was superimposed with the mandibular canal, 6 cases were superimposed with the inferior border of the mandible. Conclusion : Characteristically, these defects had a special radiographic features such as ovoid shaped well-defined radiolucency located just above or at the inferior border of the mandible between the first molar and the mandibular angle, and always inferior to the mandibular canal. The recognition of these radiographic features were diagnostically valuable.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권5호
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• pp.428-434
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• 2001

After miniplate fixation of mandibular angle fractures, fracture line stability during functional loading was evaluated. Using panoramic radiographs, 15 mandibular angle fracture patients who were treated by open reduction and one miniplate fixation along the external oblique ridge, were evaluated at postoperative 1, 4 and 8 weeks. At each time, 2 radiographs were taken: one taken during maximum biting of hardened silicone sheet on the affected side molar area and the other on the non-affected side. The distraction gap of inferior border of mandible at each time and each side was measured and these data were analysed statistically with clinical findings. The differences of inferior border distraction gap during hardened silicone sheet biting on the affected side molar area and on the non-affected side molar area at 4 week radiographs were smaller than those of 1 week's except one case. At 8 week's radiographs, the fracture lines were so stabilized that it was almost impossible to find the gap differences except one case and there were increased radiopacity along the entire fracture lines. Clinically, bony union was confirmed in all cases during plate removal performed at postoperative 6 month. By statistical analysis(paired t-test), the inferior border distraction gap during biting of hardened silicone sheet on the affected side was significantly reduced during 1 and 4 week interval(p<0.01). The differences of inferior border distraction gap during biting on the affected side molar area and on the non-affected side molar area were also significantly reduced at 1 and 4 week interval(p<0.01). But the inferior border distraction(compression) gap during non-affected side biting was not significantly changed. From these findings, it could be concluded that fracture line stability during functional loading after one miniplate fixation of mandibular angle fractures stems mainly from reduction of inferior border distraction gap during affected side biting on time interval. According to these radiographic and clinical findings, the clinical superiority of one miniplate fixation technique in mandibular angle fracture treatment could be confirmed.

• 구강회복응용과학지
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• 제28권4호
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• pp.349-357
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• 2012

이번 연구의 목적은 콘빔형 전산화단층촬영술(cone-beam computed tomography)을 이용하여 상악동 측벽의 두께를 측정하고, 이를 바탕으로 상악동 거상술을 위한 측벽창(lateral wall window)형성 시 가장 적절한 수직적 위치를 평가하는 것이다. 2010년 7월부터 2012년 6월까지 경북대학교 치과병원에 내원한 53명(남 : 36명, 여 : 17명, 평균나이 : 51.5세)의 상악동거상술 예정 환자의 콘빔형 전산화단층영상을 대상으로 하였다. 상악동 측벽의 두께는 상악 제2소구치, 제1대구치, 제2대구치 부위에서 상악동 하연을 포함하여 상악동 하연을 기준으로 수직적으로 1 mm 간격으로 6 mm 까지 측정하였고, 2회 반복 측정하여 평균을 구하였다. 상악동 측벽의 두께는 상악동 하연(Sinus Inferior Border, SIB)을 기준으로 상방 2 mm (SIB+2)까지는 2 mm 이상으로 관찰되었고, 상악동의 하연을 기준으로 3 mm 상방 (SIB+3)에서는 2 mm 미만으로 나타났으며, 상악동 하연을 기준으로 4 mm 상방에서는 두께가 거의 일정한 것으로 나타났다. 이번 연구 결과를 바탕으로 측방 접근법을 이용한 상악동 거상술에서 측벽창의 하방 위치는 상악동 측벽의 두께를 고려할 때 상악동의 하연을 기준으로 약 3 mm 상방에서 형성하는 것이 적절할 것으로 생각된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권1호
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• pp.34-39
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• 2021

Objectives: The purpose of the study was to assess the occurrence, location, and dimensions of the intraosseous vascular canal in the lateral wall of the maxillary antrum using cone-beam computed tomography (CBCT). Materials and Methods: In this retrospective study, we examined 400 CBCT scans from our archive of patients who had earlier reported to a dental teaching hospital in the United Arab Emirates. The prevalence, location, and dimensions of the lateral antral intraosseous canal (LAIC) in the maxillary antrum were evaluated by 2 examiners using standardised methods. A third examiner was consulted in cases of disagreement. Results: The prevalence of LAIC was 62.3% (249 maxillary antra) among the study population. The mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC in the posterior maxillary region was 19.83±3.12 mm. There was a significant difference (P=0.05) between the maxillary molar and premolar regions in mean distance from the most inferior point of the alveolar bone and the inferior border of the LAIC. There was no statistically significant difference in mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC between dentulous and edentulous areas (P=0.1). The G3-intrasinusal type canal less than 1mm in diameter was the most common type of LAIC. Conclusion: This study established the approximate location of the LAIC in a United Arab Emirates cohort, which will assist the oral surgeon in selecting the appropriate site for sinus lift procedures with reduced risk of surgical hemorrhage.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권3호
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• pp.214-216
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• 2010

An osteochondroma is an osseous protuberance with cartilaginous growth potential, usually arising in skeletal bone and relatively uncommon in the craniofacial bone. Osteochondroma of the craniofacial region usually occurs at the condyle or the tip of the coronoid process, and rarely arises in the mandibular body, symphysis, ramus, and similar areas. Excision of the lesion including the periosteum is curative, and recurrence or malignant change (usually to a chondrosarcoma) after treatment is rare. We present an atypical case of osteochondroma in the left mandibular inferior border with review of literature.

• Journal of Periodontal and Implant Science
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• 제26권4호
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• pp.933-948
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• 1996

The purpose of this study was to examine the anatomic structures of the mandible-inferior alveolar canal, mental foramen, mental canal-with panoramic radiography and conventional tomography and to compare both radiographic techniques in conjunction with endosseous implants. In this study 14 adult dentulous mandibles -27 cases of right and left side of mandibles- were examined and the results were as follows. 1. The distance between superior border of the inferior alveolar canal and the alveolar ridge crest showed a decreasing tendency from the mental foramen to 4cm posterior to the mental foramen. 2. The mean diameter of the inferior alveolar canal was $4.11{\pm}0.50mm$ with panoramic radiography and $3.29{\pm}0.59mm$ with conventional tomography. 3. The inferior border of the inferior alveolar canal and inferior border of the mandible was closest at 2cm posterior to the mental foramen but it was not statistically significant. the mean distance was $1l.64{\pm}2.95mm$ in panoramic radiography and $1l.68{\pm} 2.91mm$ in conventional tomography. 4. The inferior alveolar canal located lingually in bucco-lingual direction 16%(mental foramen), 54%(lcm posterior to the mental foramen), 68%(2cm posterior to the mental foramen), 50%(3cm posterior to mental foramen), 55%(4cm posterior to the mental foramen). 5. Mean length of the anterior loop of the mental canal was 2.73mm, and the loop below 2mm was 35% and 15% of mental canal was invisible in panoramic radiography. 6. The minimum interforaminal distance was 56.7mm, the maximum distance was 73.2mm and the mean distance was 66.42mm in panoramic radiography. 7. The mean distance between midpoint of the mental canal and alveolar ridge crest was 16.24mm and the mean buccolingual angulation of the mental canal was $52.98^{\circ}$ in conventional tomography. 8. In comparison of panoramic radiography and conventional tomography, inferior alveolar canal is better visualized with conventional tomography than panoramic radiography from the mental foramen to the 2cm posterior to the mental foramen, while visiblity of conventional tomography prominently decreased in 4cm posterior to the mental foramen and alveolar ridge crest is better visualized with panoramic radiography than conventional radiography at the mental foramen and at 4cm posterior to the mental foramen. In radiologic examination of anatomic structures of the mandible for endosseous implants, panoramic radiography and conventional tomography can be effectively used when it is used to overcome the anatomic limitations.

• 치과방사선
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• 제25권1호
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• pp.115-125
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• 1995

Forty-four cases of developmental salivary gland defects in 43 patients were analysed radiologically. The obtained results were as follows ; 1. It occurred more frequently in males(86 ％) than in females(14 ％). The age distribution of patients ranged from 20 to 74 years with the average being 52.7 years. 2. All but one were located between the angle of the mandible and the molar tooth. Only one patient showed bilateral occurrence. 3. The shape of the defect was ovoid(15 cases), round(10 cases), or half-ovoid(5 cases) 4. Their size ranged from 5 x 6 mm to 16 x 30 mm with the average around 9 x 14 mm. 5. Twenty-eight cases appeared to be surrounded partially(1/3 - 2/3) by a hyperostotic border. The thickness of the hyperostotic border varied ; thick(14 cases), moderate(l1 cases), thin(9 cases), or mixed(6 cases) 6. Thirteen cases were in contact with the superior border of the mandibular inferior cortex, 11 cases partially eroded the cortical plate, and 7 cases showed discontinuity of the mandibular inferior cortex. 7. Twenty-three cases were located below the mandibular canal, 13 cases overlapped the mandibular canal, and 2 cases showed slight deviation of the mandibular canal.