• 한국임상수의학회:학술대회논문집
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• 한국임상수의학회 2008년도 춘계학술대회
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• pp.133-133
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• 2008

• Restorative Dentistry and Endodontics
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• 제2권1호
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• pp.27-31
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• 1976

Eighty mandibular first premolars were injected with china ink, decalcified, cleared and used in an in vitro study to determine the number of root canals, the frequency and location of lateral canals, the location of apical foramens, the frequency of apical deltas, and the curvature of root canals. The results were as follows: 1. Most of the teeth demonstrated single canal, but 22.5% of the teeth were found to have bifurcated or trifurcated canals. 2. Of the 99 canals studied, 37.3% of the canals were found to have lateral canals and these ramifications were usually located in the apical third of the root. 3. 27 apical foramens were located directly on the root apex and 66 foramens laterally. 4. 6 canals showed mesial curvature, 49 canals distal curvature, 11 canals buccal curvature, and 25 canals lingual curvature.

• Restorative Dentistry and Endodontics
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• 제8권1호
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• pp.139-145
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• 1982

Eighty four human maxillary second premolars were injected with china. ink, decalcified, cleared and used in study, in vitro, to determine the number of root canals, the frequency and location of lateral canals, the frequency and location of transverse ansatomoses, the curvature of root canals, the location of apical foramens, and the frequency of apical deltas. The results were as follows: 1. Most of the teeth demonstrated one canals, but the only tooth was found to have two canal. 2. Of the 101 canals studied, 85.1% of the canals were found to have lateral canals and these ramifications were usually located in the apical third of the root. 3. Of the two root canals in one root, 25.4% of the canals were found to have transverse anastomoses and were usually located in the middle third of the root 4. 33.3% of apical foramens were located directly on the root apex and 66.7% of them laterally, and 46.5% of canals showed distal curvature.

• Restorative Dentistry and Endodontics
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• 제3권1호
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• pp.12-16
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• 1977

One hundred human maxillary first molars were injected with china ink, decalcified, cleared, and used in vitro study to determine the number of root canals, the frequency and location of lateral canals, canals per root, and frequency of apical deltas. The results were as follows; 1. The mesiobuccal root was found to contain a single primary canal in 53% of the teeth studied and two canals in 47 % of the teeth studied. 2. In mesiobuccal roots with two canals, the seperated apical foramen appeared 32% of the specimens and the common apical foramen 15% of the specimens. 3. Of the 347 canals studied, 26.9% of the canals were found to contain lateral canals and these ramifications were mainly located in the apical third of the root.

• Restorative Dentistry and Endodontics
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• 제6권1호
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• pp.83-86
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• 1980

Fifty human maxillary second molars were injected with china ink, decalcified, cleared, and used in vitro study to determine the number of root canals, the frequency and location of lateral canals, canals per root, and frequency of apical deltas. The results were as follows. 1. The mesiobuccal root was found to contain a single primary canal in 62% of the teeth studied and two canals in 38% of the teeth studied. 2. In mesiobuccal roots with two canals, the seperated apical foramen appeared 24% of the specimens and the common apical foramen 14% of the specimens. 3. Of the 169 canals studied, 23.1% of the canals were found to contain lateral canals and these ramifications were mainly located in the apical third of the root.

• Restorative Dentistry and Endodontics
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• 제7권1호
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• pp.139-144
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• 1981

Eighty four human maxillary first premolars were injected with china ink, decalcified, cleared and used in study, in vitro, to determine the number of root canals, the frequency and location of lateral canals, the frequency and location of transverse anastomoses, the curvature of root canals, the location of apical foramens, and the frequency of apical deltas. The results were as follows: 1. Most of the teeth demonstrated two canals, but 20.2% of the teeth were found to have one canal. 2. Of the 151 canals studied, 38.4% of the canals were found to have lateral canals and these ramifications were usually located in the apical third of the root. 3. Of the two root canals in one root, 35.7% of the canals were found to have transverse anastomoses and were usually located in the middle third of the root. 4. 15.2% of apical foramens were located directly on the root apex and 84.8% of them laterally, and 52.3% of canals showed distal curvature.

• Imaging Science in Dentistry
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• 제51권1호
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• pp.17-25
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• 2021

Purpose: This study was performed to investigate mandibular canal displacement in patients with ameloblastoma using a 3-dimensional mirrored-model analysis. Materials and Methods: The sample consisted of computed tomographic scans of patients with ameloblastoma (n=10) and healthy controls (n=20). The amount of mandibular canal asymmetry was recorded as a continuous variable, while the buccolingual (yaw) and supero-inferior (pitch) directions of displacement were classified as categorical variables. The t-test for independent samples and the Fisher exact test were used to compare groups in terms of differences between sides and the presence of asymmetric inclinations, respectively (P<0.05). Results: The length of the mandibular canal was similar on both sides in both groups. The ameloblastoma group presented more lateral (2.40±4.16 mm) and inferior (-1.97±1.92 mm) positions of the mental foramen, and a more buccal (1.09±2.75 mm) position of the middle canal point on the lesion side. Displacement of the mandibular canal tended to be found in the anterior region in patients with ameloblastoma, occurring toward the buccal and inferior directions in 60% and 70% of ameloblastoma patients, respectively. Conclusion: Mandibular canal displacement due to ameloblastoma could be detected by this superimposed mirrored method, and displacement was more prevalent toward the inferior and buccal directions. This displacement affected the mental foramen position, but did not lead to a change in the length of the mandibular canal. The control group presented no mandibular canal displacement.

• The Korean Journal of Physiology
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• 제21권1호
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• pp.91-101
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• 1987

The present experiment was carried out, in the rabbit and cat, in order to explore functional interrelationship between the vestibular semicircular canals and extraocular muscles, which are involved in the vestibulooculomotor reflex as the receptor and effector organ respectively. Semicircular canals were subjected to electrical stimulation, lymphatic fluid flow or acute freezing, and responses of the extraocular muscles were recorded in terms of changes in electromyographic activity and isometric tension. Electrical stimulation of a unilateral canal elicited contraction of the superio-medial muscle group (superior oblique, superior rectus and medial rectus muscles) in the ipsilateral eye and the inferio-lateral muscle group (inferior oblique, inferior rectus and lateral rectus muscles) in the contralateral eye. Thus a simple and distinct axiom was found in the pattern of the reflex-response of the extraocular muscles. Inhibition of the unilateral canals elicited the extraocular muscle responses contrary to those observed by excitation of the canal. Based on the present experimental results, it was demonstrated that the functional interrelations between the semicircular canals and extraocular muscles are rather equivalent in the frontal eyed cats (with binocular vision) and lateral eyed rabbits (with monocular vision). Therefore the previous thesis that the vestibuloocular relations vary from species to species awaits experimental reevaluation.

• 대한두개안면성형외과학회지
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• 제12권1호
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• pp.37-42
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• 2011

Purpose: Cancer arising from the external auditory canal is a rare disease. A lesion that seems harmless in someway, can be lethal when inadequately excised, the tumor may infiltrate nerves, the parotid and auditory tissues before re-invading the skin. Wide resection of the lesion surrounding the structure and reconstruction with an adequate plan is crucial for the treatment of this disease. Methods: Two patients with external auditory canal cancer were treated with muscle flaps and skin grafts. Lateral temporal bone resection (LTBR) was performed for complete resection of the cancer. The defect cavity was obliterated with highly vascularized tissue using pedicled sternocleidomastoid muscle, and temporalis muscle individually, combined with full thickness skin graft for covering the skin defect of the ear. Results: Clear resection margin was obtained, and both patients showed disease free survival during the follow up. There was no complications of hematoma, infection, flap loss, or wound problem in both patients. Both patient received radiation therapy, there was no osteoradionecrosis or any other complication related to radiation therapy. Conclusion: Utilizing pedicled muscle flaps for managing defects after wide resection of the external auditory canal cancer is an effective method for managing this difficult disease.

• Imaging Science in Dentistry
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• 제52권4호
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• pp.359-364
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• 2022

Purpose: The aim of this study was to investigate the prevalence of infraorbital canal protrusion in an Egyptian subpopulation using cone-beam computed tomography and to describe its radiographic representation. Materials and Methods: This retrospective cross-sectional study was conducted using the records of 77 patients and 123 maxillary sinuses. The full lengths of the sinuses were visible for the detection of infraorbital canal protrusion. The infraorbital canals were classified into 3 types based on their relation to the sinus. If the septum was present, its length and its distance from the sinus floor were measured. Qualitative and quantitative variables were described as percentages and means with standard deviations, respectively. Results: The infraorbital canal most commonly presented as the normal confined type (detected in 78.1% of sinuses), whereas the suspended (or protruded) variant was found in 14.6% of the examined sinuses. The septal length ranged from 0.9 to 5.1 mm, with a mean of 2.8±1.1 mm. The distance to the sinus floor ranged from 5.2 to 29.6 mm depending on the sinus shape and size. Conclusion: The present study indicates that protrusion of the infraorbital canal is not rare, and surgeons that use the maxillary sinuses as corridors for their procedures must be more cautious, especially in the upper lateral confines of the sinus.