Korean J Orthod.  2008 Apr;38(2):95-103. 10.4041/kjod.2008.38.2.95.

Labial and buccal surface contours of Korean normal occlusion in a three-dimensional digital model

• Chae JH
• Song JW
• Cha JY
• Choi JS
• Park YC

• KMID: 1481497
• DOI: http://doi.org/10.4041/kjod.2008.38.2.95

Abstract

OBJECTVIE: This study was performed to investigate the labio/buccal clinical crown curvatures of Korean permanent teeth and to obtain the curve-ratio data in an attempt to fabricate bracket bases fit for each individual Korean permanent tooth.
METHODS
Three-dimensional digital models were made from 30 sets of dental casts with normal anatomic structures. According to the FA points, horizontal and vertical reference planes were established and lines were drawn on the tooth surfaces in reference to these planes. The curvature was expressed as the coefficient of a quadratic equation. Lines mesial, distal, gingival and occlusal to the horizontal, vertical reference planes and the FA point were drawn.
RESULTS
The curvature measured for each line revealed that there are no significant differences between male and female, except for maxillary canines and maxillary second bicuspids (p > 0.05). There were notable differences in the mesio-distal or gingivo-occlusal curvatures among the mandibular lateral incisors, maxillary canines, maxillary and mandibular first and second bicuspids and first molars (p < 0.05).
CONCLUSIONS
The labial & buccal crown curvatures of teeth in Korean normal occlusion were measured on the mesial and distal, gingival and occlusal sides respectively in this study. Based on these data, a SWA can be developed to fit the individual features of Korean tooth crowns.

Keyword

Curvature; Straight Wire Appliance; Korean

MeSH Terms

Bicuspid
Crowns
Female
Humans
Incisor
Male
Molar
Tooth
Tooth Crown

Figure

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  Fig 1 Orapix KOD-300 scanner.

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  Fig 2 The establishment of horizontal reference plane at maxilla. Some FA points may not be on the horizontal reference plane due to average calculation.

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  Fig 3 The establishment of horizontal and vertical reference plane at maxillary first premolar.

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  Fig 4 The establishment of horizontal and vertical reference curves at maxillary first premolar (A) and first molar (B).

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  Fig 5 The features which forms axis of coordinates on maxillary second premolar. X and Y axes on the horizontal reference plane have the same Z value which is 0.

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  Fig 6 Graphs of crown curvatures in each reference plane. Left, Labial/buccal curvatures; Right, occluso/gingival curvatures. Bar show means, and error bars show 95.0% confidence limit of mean. MB, Mesiobuccal surface; DB, distobuccal surface.

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  Fig 7 Comparison of the ceramic bracket (Miso, HT, Ansan, Korea) curvatures and the mean value curvatures in horizontal (left) and vertical (right) plane at maxillary second premolar.

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