Thermo-mechanical properties in bending of a multizone nickel-titanium archwire: A retrieval analysis

• 영문명: Thermo-mechanical properties in bending of a multizone nickel-titanium archwire: A retrieval analysis
• 발행기관: 대한치과교정학회
• 저자명: Panagiotis Roulias Ioulia-Maria Mylonopoulou Iosif Sifakakis Christoph Bourauel Theodore Eliades
• 간행물 정보: 『The Korean Journal of Orthodontics』제53권 제2호, 89~98쪽, 전체 10쪽
• 주제분류: 의약학 > 기타의약학
• 파일형태: PDF
• 발행일자: 2023.03.31

영문 초록

Objective: This study aimed to compare the mechanical and thermal properties in the anterior and posterior segments of new and retrieved specimens of a commercially available multizone superelastic nickel-titanium (NiTi) archwire. Methods: The following groups of 0.016 × 0.022-inch Bioforce NiTi archwires were compared: a) anterior and b) posterior segments of new specimens and c) anterior and d) posterior segments of retrieved specimens. Six specimens were evaluated in each group, by three-point bending and bend and free recovery tests. Bending moduli (Eb) were calculated. Furthermore, the new specimens were evaluated with scanning electron microscopy/energy-dispersive X-ray spectrometry. A multiple linear regression model with a random intercept at the wire level was applied for data analysis. Results: The forces in the posterior segments or new specimens were higher than those recorded in the anterior segments or retrieved specimens, respectively. Accordingly, Eb also varied. Higher austenite start and austenite finish (Af) temperatures were recorded in the anterior segments. No statistically significant differences were found for these temperatures between retrieved and new wires. The mean elemental composition was (weight percentage): Ni, 52.6 ± 0.5; Ti, 47.4 ± 0.5. Conclusions: The existence of multiple force zones was confirmed in new and retrieved Bioforce archwires. The retrieved archwires demonstrated lower forces during the initial stages of deactivation in three-point bending tests, compared with new specimens. The Af temperature of these archwires may lie higher than the regular intraoral temperature. Even at 2 mm deflections, the forces recorded from these archwires may lie beyond biologically safe limits.

목차

INTRODUCTION

MATERIALS AND METHODS

RESULTS

DISCUSSION

CONCLUSIONS

ACKNOWLEDGEMENTS

AUTHOR CONTRIBUTIONS

CONFLICTS OF INTEREST

FUNDING

REFERENCES

키워드

Archwire Biomaterial science Nitinol Transformation temperature