• Imaging Science in Dentistry
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• 제51권4호
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• pp.351-361
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• 2021

Purpose: The clivus is a region in the anterior section of the occipital bone that is commonly imaged on large-volume cone-beam computed tomography (CBCT). There have been several reports of incidental clivus variations and certain pathological entities that have been attributed to the variations. This study aimed to evaluate the effects of these variations within the scope of dentistry. Materials and Methods: Medical databases (PubMed, Scopus, and Web of Science) were searched using a controlled vocabulary (clival anomalies, cone-beam CT, canalis basilaris medianus, fossa navicularis magna, clival variation). The search was limited to English language, humans, and studies published in the last 25 years. The articles were exported into RefWorks^® and duplicates were removed. The remaining articles were screened and reviewed for supporting information on variations of the clivus on CBCT imaging. Results: Canalis basilaris medianus and fossa navicularis magna were the most common anomalies noted. Many of these variations were asymptomatic, with most patients unaware of the anomaly. In certain cases, associated pathologies ranged from developmental (Tornwaldt cyst), to acquired (recurrent meningitis). While no distinct pathognomonic aspects were noted, there were unique patterns of radiographic diagnosis and treatment modalities. Most patients had a normal course of follow-up. Conclusion: Interpretation of CBCT volumes is a skill every dentist must possess. When reviewing large-volume CBCT scans, the clinician should be able to distinguish pathology from normal anatomic variations within the skull base. The majority of clivus variations are asymptomatic and will remain undetected unless incidentally noted on radiographic examinations.

• Journal of Oral Medicine and Pain
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• 제14권1호
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• pp.57-66
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• 1989

66 patients with temporomandibular disorders were selected for experimental group, and 45 normal subjects who were Dental students were selected for control group. Average age of experimental group was 30.5 years, Male to Female ratio was 2 : 3, and their age distribution were teen-ages to seventh decades. Transcranial radiography (TR) with Denar Accurad 100 was used for each group to get the values of width in joint spaces and to investigate the bony changes of articular surfaces and relative condylar position to articular fossa. In addition to TR, clinical interview and routine charting about amount of mandibular movements and occlusal variations were carried out in experimental group. The obtained results were as follows : 1. The mean values of joint space with in control group were 2.15mm to anterior, 2.98mm to superior and 2.29mm to posterior and the value of relative condylar position to the deepest portion of articular fossa was 0.21mm to anterior. In experimental group, those values were 2.01mm, 2.14mm 2.22mm and 0.12mm to posterior in sequence, respectively. Joint spaces in experimental group, therefore, were inclined to decreased, and relative condylar position was inclined to retrude. Joint space in control group showed symmetric condylar position, but in experimental group showed asymmetry. 2. Non-affected joints with no bony changes in experimental group showed the narrowest joint spaces which were thought to manifest the abnormal stress to non-affected side to dysfunctional state of contralateral affected joints. 3. Amount of mandibular movements in experimental group were within normal values in lateral movements and in protrusive movement but in opening movement with or without passive stretch, those were lower than normal values. Frequency of occlusal variation, for example, protrusive posterior contacts, open bite, median line shift to lateral side were inclined to increase with bony changes and with crepitus.

• 치과방사선
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• 제19권1호
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• pp.105-121
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• 1989

The author analysed tomograms and submento-vertex radiograms of 90 temporomandibular joints from 45 asymptomatic young adults. 15 had Angle class Ⅰ malocclusion, 15 classⅡ and 15 class Ⅲ. Corrected lateral tomograms were obtained in three condylar positions; centric occlusion, centric relation and 1 inch mouth opening. The condylar angulation, depth of cut, joint spaces were analysed in each radiogram. The obtained results were as follows; 1. The mean condylar angulation in Angle class Ⅰ, Ⅱ, Ⅲ group was 17.55±5.51° 13.33±8.85° 16.25±6.60° respectively, and there was no significant difference in each group. The mean condylar angulation of right side (16.62±7.23°) was larger than left side (14.80±7.33°). 2. The mean depth of cut in Angle class Ⅰ, Ⅱ, Ⅲ group was 8.13±1.61㎝, 3.05±3.80㎝, 7.75±2.19㎝, respectively. Angle class Ⅰ and class Ⅱ group revealed significant difference in measurement (p<0.0l). 3. The mean height of articular fossa in Angle class Ⅰ, Ⅱ, Ⅲ group was 8.67±3.06㎜, 9.61±2.57㎜, 8.93±2.83㎜, respectively. And the mean width of articular fossa was 19.90±2.80㎜, 19.48±3.83㎜, 20.36±4.82㎜, respectively. 4. The mean height and width of condylar head was 5.11±1.16㎜, 11.20±2.26㎜, respectively. 5. In centric occlusion, the superior joint space was the largest (3.42±1.42㎜), followed by anterior joint space (2.94±1.95㎜) and the posterior joint space (2.64±1.19㎜. In centric relation, the anterior joint space was the largest (3.86±2.17㎜), followed by the superior joint space (3.64±3.68㎜) and the posterior joint space (1.18±0.77㎜). 6. The displaced measurement from centric relation to centric occlusion was 1.10±1.04㎜ anteriorly and 0.24±0.97㎜ inferiorly. In 1 inch mouth opening state, the condylar head displaced posteroinferiorly (2.49±2.49㎜ posteriorly, 1.17±1.34㎜ inferiorly) from the apex of articular eminence. And Angle class Ⅰ and Ⅱ group, Angle class Ⅱ and Ⅲ group revealed significant difference in posterior measurement, respectively (p<0.01).

• Imaging Science in Dentistry
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• 제37권3호
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• pp.133-138
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• 2007

Purpose: The purpose of this study was to evaluate the morphologic features of posterior edentulous mandible for Korean patients using cross-sectional CT images. Materials and Methods: Computed tomographic cross-sectional views taken in 2004 and 2005 at Seoul National University Dental Hospital were analyzed by an oral and maxillofacial radiologist. Four indices were measured to meet the purpose of this study: 1) the horizontal distance between the alveolar crest and mandibular canal (Type), 2) the angle of the mandibular long axis (Angle), 3) the bucco-lingual location of mandibular canal, and 4) the depth of the submandibular fossa. The averages and standard deviations of the measurements were compared according to the location (the first and second molar area) and sex of the patients. Results: Statistically significant difference was found in Type, Angle, and submandibular fossa depth between the first and second molar area (p<0.05). However, there was no significant difference between men and women in any of the measured indices. Most of the mandibular canals were located in lingual side of posterior mandible. Conclusion: More care should be taken when an implant is installed on the mandibular second molar area.

• Clinics in Shoulder and Elbow
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• 제6권1호
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• pp.80-84
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• 2003

We report a patient with an anterior dislocation of the shoulder with uncommon bucket handle type fracture of the anterior glenoid fossa with intact glenoid labrum. The fracture fragment was displaced into the posterior aspect of the glenohumeral joint resulting in prevention of reduction of the shoulder. Excellent fixation was obtained with suture anchors and bioabsorbable interfragmentary screws. This allowed stable range of motion exercises, optimizing the patient's functional outcome.

• 한국수산과학회지
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• 제36권6호
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• pp.641-645
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• 2003

Spermatogenesis, ultrastructure, and sperm morphology of the Pacific oyster (Crassostrea gigas) were investigated with TEM and SEM. C. gigas sperm were primitive consisting of a head midpiece and tail. Sperm size (head and midpiece) was about 1.78 ${\mu}m$. Sperm morphology was similar to a sharp of a small water jar with a rough surface. Sperm had both anterior nuclear fossa (anf) and posterior nuclear fossa (pnf). Acrosome forms had a hat-like shape. The axial rod was projected in front of the acrosome. C. gigas sperm had four large mitochondria in the midpiece.

• 대한치과교정학회지
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• 제47권5호
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• pp.277-288
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• 2017

Objective: Treating Class II subdivision malocclusion with asymmetry has been a challenge for orthodontists because of the complicated characteristics of asymmetry. This study aimed to explore the characteristics of dental and skeletal asymmetry in Class II subdivision malocclusion, and to assess the relationship between the condyle-glenoid fossa and first molar. Methods: Cone-beam computed tomographic images of 32 patients with Class II subdivision malocclusion were three-dimensionally reconstructed using the Mimics software. Forty-five anatomic landmarks on the reconstructed structures were selected and 27 linear and angular measurements were performed. Paired-samples t-tests were used to compare the average differences between the Class I and Class II sides; Pearson correlation coefficient (r) was used for analyzing the linear association. Results: The faciolingual crown angulation of the mandibular first molar (p < 0.05), sagittal position of the maxillary and mandibular first molars (p < 0.01), condylar head height (p < 0.01), condylar process height (p < 0.05), and angle of the posterior wall of the articular tubercle and coronal position of the glenoid fossa (p < 0.01) were significantly different between the two sides. The morphology and position of the condyle-glenoid fossa significantly correlated with the three-dimensional changes in the first molar. Conclusions: Asymmetry in the sagittal position of the maxillary and mandibular first molars between the two sides and significant lingual inclination of the mandibular first molar on the Class II side were the dental characteristics of Class II subdivision malocclusion. Condylar morphology and glenoid fossa position asymmetries were the major components of skeletal asymmetry and were well correlated with the three-dimensional position of the first molar.

• 치과방사선
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• 제20권2호
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• pp.299-313
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• 1990

The author analysed tomographic and cephalometric radiographs of 82 temporomandibular joints from 41 symptomatic patients and 40 temporomandibular joints from 20 asymptomatic young adults. The results were as follows; 1. The mean condylar angulation in control group and patient group was 21.72±6.48° 20.13±9.14° respectively and there was no significant difference between two groups. 2. The mean depth of cut was 6.63±0.38㎝ in control group and 6.57±0.46㎝ in patient group. 3. Mean height and width of condylar head were 6.66±1.83㎜, 12.42±0.49㎜ in control group and 6.22±1.36㎜, 11.93±l.92㎜ in patient group. 4. The mean height of articular fossa was 10.20±2.04㎜ in control group and 9.89±1.98㎜ in patient group. The mean width of articular fossa was 21.08±2.08㎜ in control group and 21.24±3.03㎜ in patient group. 5. In centric occlusion the superior joint space was largest (4.15±0.93㎜), followed by the posterior joint space (2.99±0.97㎜) and the anterior joint space (2.70±0.73㎜) in control group. The superior joint space (3.47±1.31㎜) and posterior joint space (3.47±7.07㎜) were same in patient group. There was significant difference in left superior joint spaces between two groups (p<0.05). 6. The condylar position in articular fossa was displaced anteroinferiorly (0.99±3.65㎜ anteriorly, 1.75±1.01㎜ inferiorly) in control group and posteroinferiorly (3.20±4.69㎜ posteriorly, 1.25±1.87㎜ inferiorly) in patient group with 1 inch opening. In maximum opening, it was displaced anteroinferiorly (6.09±3.55㎜ anteriorly, 1.38±2.47㎜ inferiorly) in control group and anteroinferiorly (1.70±5.96㎜ anteriorly, 1.37±1.85㎜ inferiorly) in patient group. There was significant difference in anteroposterior position of both condyles with 1 inch opening and maximum opening between two groups (p<0.01). 7. The mean inclination of upper central incisor and the posterior inclination of articular eminence in control group was 65.60±6.04° 58.88±9.18° in control group, and 67.14±8.41°, 59.70±9.08° in patient group respectively. There was no significant correlation between two groups.

• 대한견주관절학회:학술대회논문집
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• 대한견주관절학회 1999년도 학술대회
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• pp.38-40
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• 1999

$\cdot$ Arthroscopic management is the effective method with acceptable results for coronoid impingement of stiff elbow contributing to the functional improvement and pain relief. $\cdot$ The functional improvement and pain relief seem to be affected by the severity of a degenerative change of the elbow joint. $\cdot$ Excision of coronoid process is required in a marked limitation of further flexion in addition to deeping of the coronoid fossa and anterior capsular release. $\cdot$ Excision of olecranon tip or posterior capsular release are effective method in severe flexion contracture.

• Journal of Korean Neurosurgical Society
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• 제55권3호
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• pp.164-166
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• 2014

Ganglioglioma is an infrequent tumor of the central nervous system (CNS); mostly supratentorial region. But, they can occur anywhere in the central nervous system such as brainstem, cerebellopontine angle (CPA), thalamus, optic nerve and spinal cord. Although it occurs rarely, ganglioglioma should be included in the differential diagnosis of a posterior fossa mass because early recognition is important for treatment and patient counseling.