세라믹 브라켓의 제거 시 Er:YAG 레이저의 효능
Efficiency of ceramic bracket debonding with the Er:YAG laser
1
조회
0
다운로드
2
인용
0
참고문헌
키워드
초록
본 연구에서는 세라믹 브라켓 제거에 Er:YAG 레이저 조사가 도움이 되는지 알아보고, 브라켓 제거에 적합한 레이저 조사 방법을 연구하였으며, 또 이렇게 적용된 레이저가 치수와 법랑질에 손상을 주는지도 알아보았다. 총 190개의 치아, 단결정 세라믹 브라켓(MISO), 다결정 세라믹 브라켓(Transcend series 6000)과 KEY Laser3를 사용하였다. 실험군은 세라믹 브라켓의 종류(단결정, 다결정)와 레이저의 에너지(140, 300, 450, 600 mJ)에 따라 분류하였으며, 레이저를 브라켓당 두 곳에 1펄스씩 조사하고, 전단 강도를 측정하였다. 대조군은 레이저를 조사하지 않는 군으로 하였다. 레이저 조사에 의한 열 효과는 브라켓 하방 법랑질과 치수강에서 측정하였으며, 전단 강도 측정 후 치면에 남아있는 접착제의 양을 접착제 잔류 지수(adhesive remnant index)를 이용하여 평가하였다. 레이저 조사로 인한 접착제의 파괴 양상과 법랑질 표면 변화를 주사전자현미경으로 관찰하였다. 모든 세라믹 브라켓군에서 레이저 에너지가 증가할수록 전단 강도는 유의하게 감소하였다. 또한, 브라켓 하방 법랑질에서 최대 온도 변화는 평균 3.78oC 상승에 그쳤으며, 치수강에서 최대 온도 변화는 평균 0.9oC 상승에 그쳤다. 주사전자현미경을 이용한 법랑질과 접착제 단면 관찰에서 접착제 표면이 레이저에 의해 붕괴되어 분화구 모양의 구덩이로 관찰되었으며, 일부 시편에서 약 10 - 30μm의 법랑질 손상이 발견되었다. Transbond XT로 부착된 단결정 도재 브라켓(MISO)의 디본딩에 Er:YAG 레이저를 이용할 경우, 300 - 450 mJ의 레이저 에너지를, 그리고 다결정 도재 브라켓(Transcend series 6000)의 경우는 450 mJ 정도의 에너지를 사용하는 것이 효과적이고 안전할 것으로 생각된다.
Abstract
The aim of this study was to find out whether Er:YAG laser can aid in debonding ceramic brackets, and to see what kind of method will be the most appropriate for debonding. Methods: One hundred and ninety teeth, monocrystalline brackets (MISOTM, HT, Ansan-Si, Korea), polycrystalline brackets (TranscendTM series 6000, 3M Untek, Monrovia, CA, USA) and the KEY Laser3 (KavoDental, Biberach, Germany) were used. Experimental groups were classified according to the type of ceramic brackets, and the amount of laser energy (0, 140, 300, 450, 600 mJ). After applying laser on the bracket at two points at 1 pulse each, the shear bond strength was measured. The effect of heat caused by laser was measured at the enamel beneath the bracket and pulp chamber. After measuring the shear bond strength, adhesive residue was evaluated and enamel surface was investigated using SEM. Results: All ceramic bracket groups showed a significant decrease in shear bond strength as the laser energy increased. The greatest average temperature change was 3.78oC on the enamel beneath the bracket and 0.9oC on the pulp chamber. Through SEM, crater shape holes caused by the laser was seen on the enamel and adhesive surfaces. Conclusions: If laser is applied on ceramic brackets for debonding, 300 - 450 mJ of laser energy will be safe and efficient for monocrystalline brackets (MISOTM), and about 450 mJ for polycrystalline brackets (TranscendTM series 6000).
참고문헌 (31)
- Bishara SE, "Ceramic bracket and the need to develop national standards", Am J Orthod Dentofacial Orthop, 117, pp.595~597 (2000)
- Arici S, "The force levels required to mechanically debond ceramic brackets: an in vitro comparative study", Eur J Orthod, 22, pp.327~334 (2000)
- Bishara SE, "Comparisons of different debonding techniques for ceramic brackets: an in-vitro study. Part 1. Background and methods", Am J Orthod Dentofacial Orthop, 98, pp.145~153 (1990)
- Storm ER, "Debonding ceramic brackets", J Clin Orthod, 24, pp.91~94 (1990)
- Bishara SE, "Comparisons of different debonding techniques for ceramic brackets: an in-vitro study. Part II. Findings and clinical implications", Am J Orthod Dentofacial Orthop, 98, pp.263~273 (1990)
- Krell KV, "Orthodontic bracket removal using conventional and ultrasonic debonding techniques, enamel loss, and time requirements", Am J Orthod Dentofacial Orthop, 103, pp.258~266 (1993)
- Rueggeberg FA, "Thermal debracketing of orthodontic resins", Am J Orthod Dentofacial Orthop, 98, pp.56~65 (1990)
- Larmour CJ, "An ex vivo investigation into the effects of chemical solvents on the debond behaviour of ceramic orthodontic brackets", Br J Orthod, 25, pp.35~39 (1998)
- Strobl K, "Laser-aided debonding of orthodontic ceramic brackets", Am J Orthod Dentofacial Orthop, 101, pp.152~158 (1992)
- Tocchio RM, "Laser debonding of ceramic orthodontic brackets", Am J Orthod Dentofacial Orthop, 103, pp.155~162 (1993)
- Mimura H, "Comparison of different bonding materials for laser debonding", Am J Orthod Dentofacial Orthop, 108, pp.267~273 (1995)
- Rickabaugh JL, "Ceramic bracket debonding with the carbon dioxide laser", Am J Orthod Dentofacial Orthop, 110, pp.388~393 (1996)
- Ma T, "In vitro comparison of debonding force and intrapulpal temperature changes during ceramic orthodontic bracket removal using a carbon dioxide laser", Am J Orthod Dentofacial Orthop, 111, pp.203~210 (1997)
- Obata A, "Super pulse CO2 laser for bracket bonding and debonding", Eur J Orthod, 21, pp.193~198 (1999)
- 김유정, "레이저를 이용한 도재 브라켓 제거 술식 후 치수의 조직학적 변화", 대한치과교정학회지, 34(4), pp.343~350 (2004), 대한치과교정학회
- Hayakawa K, "Nd:YAG laser for debonding ceramic orthodontic brackets", Am J Orthod Dentofacial Orthop, 128, pp.638~647 (2005)
- Coluzzi DJ, "Fundamentals of dental lasers: science and instruments", Dent Clin North Am, 48, pp.751~770 (2004)
- Guttenberg SA, "Laser physics and tissue interaction", Oral Maxillofacial Surg Clin North Am, 16, pp.143~147 (2004)
- Masato M, "CO2 laser technique", pp.2~23 (2001), Tohan Co
- Moritz AF, "Oral laser application", pp.38~55 (2007), Quintessence Pub Co
- International Standards Organization, "ISO", TR 106, WG 11. Dentistry: Dental materials - Testing of adhesive to tooth structure, 2003[DOI]
- Graber TM, "Risk management in orthodontics. 1st ed", pp.20~42 (2003), Quintessence Pub Co
- Chirila TV, "Laser- induced damage to transparent polymers: chemical effect of short-pulpsed (Q-switched) Nd:YAG laser radiation on ophthalmic acrylic biomaterials", I. A review. Biomaterials, 11, pp.305~312 (1990)
- Eliades T, "Direct light transmittance through ceramic brackets", Am J Orthod Dentofacial Orthop, 107, pp.11~19 (1995)
- Zach L, "Pulp response to externally applied heat", Oral Surg Oral Med Oral Pathol, 19, pp.515~530 (1965)
- Chang JC, "Laser-induced thermal events in empty and pulp-filled dental pulp chambers", Lasers Surg Med, 22, pp.46~50 (1998)
- Attrill DC, "Thermal effects of the Er:YAG laser on a simulated dental pulp: a quantitative evaluation of the effects of a water spray", J Dent, 32, pp.35~40 (2004)
- Proffit WR, "Contemporary orthodontics. 4th ed", pp.415~ (2007), Mosby Co
- Delfino CS, "Effect of Er:YAG laser energy on the morphology of enamel", adhesive system interface, 2006, pp.252, 8476~8481
- Pus MD, "Enamel loss due to orthodontic bonding with filled and unfilled resins using various clean-up techniques", Am J Orthod, 77, pp.269~283 (1980)
- Al Shamsi AH, "Three-dimensional measurement of residual adhesive and enamel loss on teeth after debonding of orthodontic brackets: an in-vitro study", Am J Orthod Dentofacial Orthop, 131, pp.301.e9~301.e15 (2007)