• Journal of Oral Medicine and Pain
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• v.23 no.4
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• pp.369-377
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• 1998

A patient with TMJ osteoarthritis and anterior open bite was treated with an intermaxillary traction device. Pretreatment examination revelaed a pain in both TMJ during mouth opening, moderate tendernesso f left sternocleidomastoid and right trapezius muscles. Anterior open Bite was aobserved with interincisal distance of 2mm. Tomograms and MRI showed anterior disc displacement withouit reductoin of both temporomandibular joints, and the condyles were flattened and slightly eroded. A pair of full-coverage occlusal appliances was made on both maxillary and mandibular dentition, with pivoting fulcrum on the site of the second moalr. Traction force was gained by the intermaxillary orthodontic elastics which were hooked by orthodontic brackets on the labial surfaces of the upper and lower anterior and premolar teeth. After 8 weeks of traction treatment, the joint pain was subsided completely and the anterior open bite was closed to get an edge to edge relationship of anterior teeth.

• Imaging Science in Dentistry
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• v.47 no.4
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• pp.241-246
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• 2017

Purpose: The aim of this study was to compare the root surface areas of the maxillary permanent teeth in Thai patients exhibiting anterior normal overbite and in those exhibiting anterior open bite, using cone-beam computed tomography (CBCT). Materials and Methods: CBCT images of maxillary permanent teeth from 15 patients with anterior normal overbite and 18 patients with anterior open bite were selected. Three-dimensional tooth models were constructed using Mimics Research version 17.0. The cementoenamel junction was marked manually. The root surface area was calculated automatically by 3-Matic Research version 9.0. The root surface areas of each tooth type from both types of bite were compared using the independent t-test (P<.05). The intraclass correlation coefficient was used to assess intraobserver reliability. Results: The mean root surface areas of the maxillary central and lateral incisors in individuals with anterior open bite were significantly less than those in those with normal bite. The mean root surface area of the maxillary second premolar in individuals with anterior open bite was significantly greater than in those with normal bite. Conclusion: Anterior open-bite malocclusion might affect the root surface area, so orthodontic force magnitudes should be carefully determined.

• Journal of the korean academy of Pediatric Dentistry
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• v.6 no.1
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• pp.27-33
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• 1979

The author studied the response to the stimulation of an electric pulp stimulator of healthy 854 permanent anterior teeth in 122 children aged from six to eleven years old, during different stages of tooth development. The results were as followings: 1) In completely open apices, 13.1% (18 teeth) showed positive responses, and 86.9% (120 teeth) showed negative responses. In two-thirds open apices 33.1% (75 teeth) showed positive responses, and 66.9% (152 teeth) showed negative responses. In one-third open apices 57.8% (118 teeth) showed positive responses, and 42.2% (86 teeth) showed negative responses. In closed apices 80.0% (228 teeth) showed positive responses, and 20.0% (57 teeth) showed negative responses. 2) The number of positive responses increased in each upper and lower central incisors during the stages of root development, but not in upper lateral incisors. 3) There were no significant differences statistically in responses between the teeth of the right and left sides and the upper and the lower jaw, in the same stages of root development.

• The Korean Journal of Zoology
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• v.6 no.1
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• pp.15-20
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• 1963

The characteristics of the pharyngeal bones and their teeth in Korean Cyprinids fishes, as a rule, are summarized as follow : 1. The materials 13 genera and 17 species from Nak Dong River. 2. Breadth of bone about 2.8(Cyprinus carpio) to 4.9(Culter brevicauda) in bone length. Length of bone about 8.5(Carassius carassius ) to 20.2 (Pseudogobio esocinus ) in body length. Breadth of pitted surface about 66%(Carassius carassius) to 85%(Acanthorhodeus asmussi ) of breadth of bone. 3. The position and distinct ratio of anterior angle correlated. 4. Posterior limb always longer than anteriro, but posterior edentulous process not shorter than anterior's or equal. 5. Zacco platypus with pitted surface on anterior limb , but Z.temmincki without it. 6. Teeth one to three rowed in accordance with the differences of each genus : a. one rowed genera ..... Carassius , Pseudorasbora, Sarcocheilichthys (Sakiyae), Pungtungia, Acheilognathus, Acanthorhodeus. b. two rowed genera ........ Pseudogobio, Gnathopogon, Tribolodon. c. Three rowed genera .... Cyprinus, Hemibarbus, Zacco , Culter 7. Teeth of main (primary ) row with four or five teeth is symmetrized exceptive three genera (Tribolodon, Zacco, Culter). 8. Grinding surface and bill type correlated. 9. In Acheilognathus, A.Yamatsutae have one or two indistinct serration but each individual is unlike.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.45-51
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• 1982

An endodontically treated tooth is likely to be brittle than a vital tooth. Internal structure of the tooth has been weakened due to a significant removal of dentin by coronal access, canal preparation. There are many controversies concerning with various methods of reinforcing an intact anterior tooth that has endodontic treatment. In this experiment, 128 extracted maxillary anterior teeth were endodontically treated, and prepared with 4 methods of restorations; Composite resin filling with zinc phosphate cement, composite resin filling without zinc phosphate cement, composite resin filling with post, and metal crown with post. An Instron testing machine was used to measure the fracture loads of the specimens. The means of the failure loads for the 4 groups were compared by F-test statistically and the failure modes were observed. The results were as follows; 1. There were no statistically significant difference between the failure loads of the four methods of restoration. 2. Teeth without post were fractured in a horizontal or oblique plane through upper or middle third of the root. 3. In the posted teeth, fractures were occurred around the post. 4. In the metal crowned teeth with post, the fracture were occurred around the post or coronal area.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.1
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• pp.119-125
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• 1999

Conventional interproximal stripping using abrasive strips is normally limited to the anterior teeth. The strips must be forced between the contact points of the teeth creating patient discomfort and the risk of cutting gingival tissue. Air-rotor stripping(ARS) with Essix anterior anchor enables the clinician to remove a precise amount of interproximal enamel to create space, primarily in the buccal quadrants, for aligning or retracting teeth. In selected cases, ARS can resolve significant differences in ratios of tooth site to arch length, and the technique can become an alternative to extraction or expansion. ARS can create substantially more space than that is usually obtained by conventional interproximal stripping, and it can be done at any time during treatment without discomfort to the patient and without adversely affecting the function of the dentition, interocclusal relations, or tooth form.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.135-141
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• 2004

Statement of problem: Arrangement and angulation of clinical crown is very important for esthetic restoration in the upper anterior dentition. However, there was no clinical criteria to mesial angulation of the crown for Korean. Purpose: This study was undertaken to estimate the mesial angulation of the crown of the anterior teeth and the Oh's E-triangle made of the inter-pupillary line and the mesial inclination lines of the canines. Material and Method: 270 portraits of Korean were used for this study. The mesial angulation of the upper anterior teeth and the relationship of the inter-pupillary line and the mesial inclination lines of the canines were measured with the tools of PhotoShop software on the scanned images. Results: The angulation between the clinical crowns having a same name in the upper anterior dentition were $3.6^{\circ}$ between the central incisors, $8.6^{\circ}$ between the lateral incisors, and $13.6^{\circ}$ between the canines. There was no significance according to occupation and gender( P > 0.05). The ratio of height to base line of Oh's E-triangle was 4.47. 81.6% of the subjects showed the mesial inclination line of the canine passed by mesial border area of pupil. Conclusion: These data for Korean would be useful clinically to give the esthetic arrangement and to make the contour of upper anterior teeth.

• The Korean Journal of Malacology
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• v.27 no.2
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• pp.91-97
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• 2011

This study examines the morphological features of larval and postlarval shells of the paedomorphic bivalve Crenella decussata Montagu, 1808 from the Sea of Japan. During the early morphogenesis of the shell of C. decussata the following characteristics appear: prodissoconch I -the anterior and posterior provincular teeth, a broad primary ligament pit located on the chondrophore; nepioconch - the anterior and posterior juvenile teeth,primary lateral teeth, fine commarginal and radial sculpture. Larvae of C. decussata distinctly differ from other mytilid larvae by a D-shaped shell, absence of umbo, astraight hinge margin, and homogeneous fine-grained sculpture without co-marginal lines of growth. These shell characters indicate lecithotrophic development of this species. Some morphostructures are revealed which might be used in crenellin taxonomy.

• The Journal of Advanced Prosthodontics
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• v.2 no.3
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• pp.106-110
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• 2010

The severe wear of anterior teeth facilitates the loss of anterior guidance, which protects the posterior teeth from wear during excursive movement. The collapse of posterior teeth also results in the loss of normal occlusal plane and the reduction of the vertical dimension. This case report describes 77-year-old female, who had the loss of anterior guidance, the severe wear of dentition, and the reduction of the vertical dimension. Occlusal overlay splint was used after the decision of increasing vertical dimension by anatomical landmark, facial and physiologic measurement. Once the compatibility of the new vertical dimension had been confirmed, interim fixed restoration and the permanent reconstruction was initiated. This case reports that a satisfactory clinical result was achieved by restoring the vertical dimension with an improvement in esthetics and function.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.9 no.1
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• pp.19-23
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• 1979

A study was made primarily to investigate vertical and horizontal distortion of the image at the apical region of the dental roots in orthopantomographs. The subjects consisted of two dry skulls with radiopaque materials attached to root surface. Measuring of the width and length of each predetermined point at 23 teeth was performed in dry skulls and radiographic films. The results obtained were as follows; 1. There was overall magnification of image in the vertical dimension. And anterior portion had greater magnification rate than posterior portion, while lower anterior portion had less magnification rate than upper anterior portion. 2. There was reduction of the image in the horizontal dimension of the teeth, because of the position relation between dry skull and image layer of the orthopantomograph. 3. There was a significant difference in distortion rate between the oposite teeth. 4. Cervical portion of the tooth had more decreased rate of horizontal distortion than apical portion.