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Trial Production of Titanium Orthodontic Brackets Fabricated by Metal Injection Molding (MIM) with Sintering

Department of Orthodontics, materials, Institute of Dental Science, Matsumoto Dental College, 1780 Gohbara Hirooka, Shiojiri, Nagano 399-07, Japan

M. Ito

Department of Biomaterials, Institute of Dental Science, Matsumoto Dental College, 1780 Gohbara Hirooka, Shiojiri, Nagano 399-07, Japan

A. Obata

Department of Orthodontics, Institute of Dental Science, Matsumoto Dental College, 1780 Gohbara Hirooka, Shiojiri, Nagano 399-07, Japan

Y. Koh

Department of Orthodontics, Institute of Dental Science, Matsumoto Dental College, 1780 Gohbara Hirooka, Shiojiri, Nagano 399-07, Japan

T. Yamagishi

Department of Biomaterials, Institute of Dental Science, Matsumoto Dental College, 1780 Gohbara Hirooka, Shiojiri, Nagano 399-07, Japan

Y. Oshida

Dental Materials, Indiana University School of Dentistry, Indianapolis, Indiana 46202, USA

Safety and esthetics are two indispensable factors to consider when fabricating orthodontic brackets. However, these factors are not easily achieved when conventional techniques (including forging and casting) are used in the mass production of titanium brackets, albeit the brackets exhibit excellent biocompatibility. In the present study, orthodontic brackets were manufactured by metal powder injection molding with sintering. Brackets with three different base designs were made and subjected to compression shear tests for evaluation of their bonding strength to enamel substrate. The shapes given to the dimple of the base were spherical, oval, and grooved. The maximum shear forces for each type were 11.1 kgf, 7.6 kgf, and 18.5 kgf, respectively. The bonding strengths of the titanium bracket were equivalent to those obtained with conventional stainless steel brackets. Moreover, uniform distribution of Vickers hardness values (average, 240 ± 40 Hv) measured at three locations indicated that the titanium bracket was uniformly sintered. Accordingly, titanium brackets thus fabricated exhibit a potential for clinical application.

Key Words: metal injection molding • titanium • orthodontic bracket • bonding strength • Vickers hardness

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Journal of Dental Research, Vol. 75, No. 7, 1491-1496 (1996)
DOI: 10.1177/00220345960750070901


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This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Deguchi, T. Articles by Oshida, Y. Search for Related Content PubMed PubMed Citation Articles by Deguchi, T. Articles by Oshida, Y. Social Bookmarking                         What's this?