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Abstract
OBJECTIVE To compare the clinical performance of brackets bonded to anterior and posterior teeth, including second molars. MATERIALS AND METHODS One operator, using the straight-wire technique, bonded metallic brackets to the teeth of 127 consecutive patients. All patients were observed for 12 months during their regular orthodontic appointments. Bracket failures were recorded and summarized for statistical analysis. The Cox proportional hazards regression analysis was performed to evaluate bracket failure rates. RESULTS Statistically significant differences in survival rates were observed between molar tubes and anterior brackets (P < .05). Twelve-month failure rates of incisor, canine, premolar, and molar brackets were 3.6, 1.6, 4.8, and 11.6%, respectively. The first and second molar did not show significant difference in bond failure. Young patients (age <18 years) showed a higher failure rate than old patients (≥18 years). CONCLUSIONS Brackets directly bonded to the buccal surfaces of molars failed significantly more often than those directly bonded to anterior teeth or premolars, but showed acceptable failure rate especially in adult patients. Bonding on second molars seems to be as reliable as bonding on the first molars.
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Affiliation(s)
- Min-Ho Jung
- a Adjunct Associate Professor, Department of Orthodontics, Dental Research Institute and School of Dentistry, Seoul National University; Private practice, Seoul, Korea
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3
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Nguyen TT, Miller A, Orellana MF. Characterization of the porosity of human dental enamel and shear bond strength in vitro after variable etch times: initial findings using the BET method. Angle Orthod 2011; 81:707-715. [PMID: 21341996 PMCID: PMC8919743 DOI: 10.2319/083010-506.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2010] [Accepted: 12/01/2010] [Indexed: 02/07/2024] Open
Abstract
OBJECTIVES (1) To quantitatively characterize human enamel porosity and surface area in vitro before and after etching for variable etching times; and (2) to evaluate shear bond strength after variable etching times. Specifically, our goal was to identify the presence of any correlation between enamel porosity and shear bond strength. MATERIALS AND METHODS Pore surface area, pore volume, and pore size of enamel from extracted human teeth were analyzed by Brunauer-Emmett-Teller (BET) gas adsorption before and after etching for 15, 30, and 60 seconds with 37% phosphoric acid. Orthodontic brackets were bonded with Transbond to the samples with variable etch times and were subsequently applied to a single-plane lap shear testing system. RESULTS Pore volume and surface area increased after etching for 15 and 30 seconds. At 60 seconds, this increase was less pronounced. On the contrary, pore size appears to decrease after etching. No correlation was found between variable etching times and shear strength. Samples etched for 15, 30, and 60 seconds all demonstrated clinically viable shear strength values. CONCLUSIONS The BET adsorption method could be a valuable tool in enhancing our understanding of enamel characteristics. Our findings indicate that distinct quantitative changes in enamel pore architecture are evident after etching. Further testing with a larger sample size would have to be carried out for more definitive conclusions to be made.
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Affiliation(s)
| | - Arthur Miller
- Professor of Orthodontics, Orthodontic Graduate Program, School of Dentistry, University of California San Francisco, Calif
| | - Maria F. Orellana
- Assistant Professor of Orthodontics, Orthodontic Graduate Program, School of Dentistry, University of California San Francisco, Calif
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6
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Orellana M, Nelson A, Carey J, Heo G, Boychuk D, Major P. Surface Analysis of Etched Molar Enamel by Gas Adsorption. J Dent Res 2008; 87:532-6. [DOI: 10.1177/154405910808700607] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Much research has been devoted to the study of etched enamel, since it is critical to bonding. Currently, there are no precise data regarding the etched-enamel specific surface area. The aim of this study was to characterize, by two different methods, the surface of human dental enamel in vitro after being etched. It was hypothesized that differences would be observed between specimens in terms of specific surface area and grade of etching. Sixteen third molar enamel samples were etched for 30 sec with 37% phosphoric acid prior to being viewed by SEM. Etched enamel surfaces were graded according to the Galil and Wright classification. The total surface area of etched samples was determined by the BET gas absorption method. A substantial variability in total surface area was observed between and among samples. A Pearson’s Correlation Coefficient showed a lack of relationship between etch pattern and total surface area.
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Affiliation(s)
- M.F. Orellana
- Orofacial Sciences, Division of Orthodontics, School of Dentistry, University of California, San Francisco, 707 Parnassus Ave., D-1011, Box 0438, San Francisco, CA 94143-0438, USA
- Chemical and Materials Engineering, Faculty of Engineering, University of Alberta, Canada, and The Dow Chemical Company, Corporate Research and Development, Midland, MI 48674, USA
- Mechanical Engineering, Faculty of Engineering, and Faculty of Medicine and Dentistry, University of Alberta, Canada
- Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta, Canada; and
- Oral and Maxillofacial Surgery, School of Dentistry, University of California, San Francisco
| | - A.E. Nelson
- Orofacial Sciences, Division of Orthodontics, School of Dentistry, University of California, San Francisco, 707 Parnassus Ave., D-1011, Box 0438, San Francisco, CA 94143-0438, USA
- Chemical and Materials Engineering, Faculty of Engineering, University of Alberta, Canada, and The Dow Chemical Company, Corporate Research and Development, Midland, MI 48674, USA
- Mechanical Engineering, Faculty of Engineering, and Faculty of Medicine and Dentistry, University of Alberta, Canada
- Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta, Canada; and
- Oral and Maxillofacial Surgery, School of Dentistry, University of California, San Francisco
| | - J.P.R. Carey
- Orofacial Sciences, Division of Orthodontics, School of Dentistry, University of California, San Francisco, 707 Parnassus Ave., D-1011, Box 0438, San Francisco, CA 94143-0438, USA
- Chemical and Materials Engineering, Faculty of Engineering, University of Alberta, Canada, and The Dow Chemical Company, Corporate Research and Development, Midland, MI 48674, USA
- Mechanical Engineering, Faculty of Engineering, and Faculty of Medicine and Dentistry, University of Alberta, Canada
- Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta, Canada; and
- Oral and Maxillofacial Surgery, School of Dentistry, University of California, San Francisco
| | - G. Heo
- Orofacial Sciences, Division of Orthodontics, School of Dentistry, University of California, San Francisco, 707 Parnassus Ave., D-1011, Box 0438, San Francisco, CA 94143-0438, USA
- Chemical and Materials Engineering, Faculty of Engineering, University of Alberta, Canada, and The Dow Chemical Company, Corporate Research and Development, Midland, MI 48674, USA
- Mechanical Engineering, Faculty of Engineering, and Faculty of Medicine and Dentistry, University of Alberta, Canada
- Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta, Canada; and
- Oral and Maxillofacial Surgery, School of Dentistry, University of California, San Francisco
| | - D.G Boychuk
- Orofacial Sciences, Division of Orthodontics, School of Dentistry, University of California, San Francisco, 707 Parnassus Ave., D-1011, Box 0438, San Francisco, CA 94143-0438, USA
- Chemical and Materials Engineering, Faculty of Engineering, University of Alberta, Canada, and The Dow Chemical Company, Corporate Research and Development, Midland, MI 48674, USA
- Mechanical Engineering, Faculty of Engineering, and Faculty of Medicine and Dentistry, University of Alberta, Canada
- Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta, Canada; and
- Oral and Maxillofacial Surgery, School of Dentistry, University of California, San Francisco
| | - P.W. Major
- Orofacial Sciences, Division of Orthodontics, School of Dentistry, University of California, San Francisco, 707 Parnassus Ave., D-1011, Box 0438, San Francisco, CA 94143-0438, USA
- Chemical and Materials Engineering, Faculty of Engineering, University of Alberta, Canada, and The Dow Chemical Company, Corporate Research and Development, Midland, MI 48674, USA
- Mechanical Engineering, Faculty of Engineering, and Faculty of Medicine and Dentistry, University of Alberta, Canada
- Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta, Canada; and
- Oral and Maxillofacial Surgery, School of Dentistry, University of California, San Francisco
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9
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Hobson RS, Rugg-Gunn AJ, Booth TA. Acid-etch patterns on the buccal surface of human permanent teeth. Arch Oral Biol 2002; 47:407-12. [PMID: 12015222 DOI: 10.1016/s0003-9969(02)00008-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Since the introduction of acid etching to aid adhesion to enamel, there has been much research into dental materials to improve bond strength, but little into the surface topography of etched enamel, particularly regarding possible variations between tooth types. This study was a systematic investigation into the quality and quantity of etch patterns found on the buccal surfaces of different human permanent teeth. Twenty-nine orthodontic patients had high-resolution silicone impressions taken of the buccal surface of incisor, canine, premolar and molar, upper and lower teeth, following etching for 30s with 37% phosphoric acid. Impressions (n=266) were replicated in epoxy resin and examined under high magnification in a scanning electron microscope. A modification of the classification of Galil and Wright was used, with histometric techniques, to quantify the quality of etch patterns on enamel surfaces where orthodontic brackets are typically bonded. There was no difference between right and left or between upper and lower teeth of the same type (P>0.05). There was a general trend toward the increasing occurrence of no etch (type D) from anterior to posterior teeth, and a trend toward fewer good-quality etches (types A and B) in the same direction. Etch types A and B were found to occupy the smallest area on the etched buccal surface enamel. The greatest amount of type A etch 'ideal' was found on the lower incisors, yet it occupied less than 5% of the etched buccal surface enamel. The greatest area of etched enamel surface was occupied by type C (etched, but enamel prisms not evident). It was concluded that there is a significant difference in the acid-etch patterns achieved on different tooth types, which suggests that bond-strength studies should be performed with a single tooth type or that an equal number of different tooth types be included.
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Affiliation(s)
- R S Hobson
- Child Dental Health, Newcastle Dental School, Framlington Place, Newcastle upon Tyne NE2 4BW, UK.
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Strang R, Whitters CJ, Brown D, Clarke RL, Curtis RV, Hatton PV, Ireland AJ, Lloyd CH, McCabe JF, Nicholson JW, Scrimgeour SN, Setcos JC, Sherriff M, van Noort R, Watts DC, Woods D. Dental materials: 1996 literature review. Part 2. J Dent 1998; 26:273-91. [PMID: 9611932 DOI: 10.1016/s0300-5712(97)00064-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
This critical review of the published literature on dental materials for the year 1996 has been compiled by the Dental Materials Panel of the UK. It continues the series of annual reviews started in 1973 and published in the Journal of Dentistry. Emphasis has been placed upon publications which report upon the materials science or clinical performance of the materials. The review has been divided by accepted materials classifications (fissure sealants, glass polyalkenoate cements, dentine bonding, dental amalgam, endodontic materials, casting alloys, resin-bonded bridges and ceramo-metallic restorations, ceramics, denture base resins and soft lining materials, impression materials, implants materials, orthodontic materials, biomechanics and image processing, resin composites and casting investment materials and waxes). Three hundred and thirteen articles have been reviewed.
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