Journal of dental hygiene science (치위생과학회지)

The Korean Society of Dental Hygiene Science (한국치위생과학회)
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The Influence of Different Gypsum Materials on the Accuracy from Complete Arch Digital Impression

전악의 디지털 인상 채득 시 치과용 모형재가 디지털 모형 정확성에 미치는 영향

  • Kim, Ki-Baek (Department of Health Science Specialized in Dental Lab. Science & Engineering, Graduate School, Korea University) ;
  • Lee, Gyeong-Tak (Department of Health Science Specialized in Dental Lab. Science & Engineering, Graduate School, Korea University) ;
  • Kim, Hae-Young (Department of Health Science Specialized in Dental Lab. Science & Engineering, Graduate School, Korea University) ;
  • Kim, Jae-Hong (Department of Health Science Specialized in Dental Lab. Science & Engineering, Graduate School, Korea University)
  • 김기백 (고려대학교 일반대학원 보건과학과 치의기공전공) ;
  • 이경탁 (고려대학교 일반대학원 보건과학과 치의기공전공) ;
  • 김혜영 (고려대학교 일반대학원 보건과학과 치의기공전공) ;
  • 김재홍 (고려대학교 일반대학원 보건과학과 치의기공전공)
  • Published : 2012.12.31
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Abstract

This study was performed to measure the accuracy of different gypsum materials by a white light dental scanner. A master model with the prepared lower full arch tooth was used. The type IV and scannable stone were used for 20 stone casts (10 casts each) duplicated a master model of mandible. The distance between the reference points were measured and analyzed by the Delcam $Copycad^{(R)}$ (Delcam Plc, UK) 3D graphic software. The t-student test for paired samples were used for statistical analysis. The mean differences to master model for type IV stone and scannable stone model were 0.29~0.56 mm, and 0.17~0.35 mm, respectively. There were statistical differences in dimensional accuracy for full arch impression between the master model and type IV/scannable stone (p<0.05). Two different gypsum materials showed clinically acceptable accuracies of full arch digital impression produced by them. Besides, in both gypsum materials, the differences to the master model detected appear to provide enough accuracy for clinical application.

본 연구는 치과용 모형재 중 4형(type IV)석고와 스캔용(scannable)석고를 이용하여 작업모형을 제작한 후, 치과용 백색광 스캐너를 이용하여 3차원 디지털 모형으로 전환한 데이터의 계측지점간 거리를 측정하여, 그 결과 값을 토대로 이종의 치과용 석고가 3차원 디지털 모형의 크기재현 시 정확성여부를 비교하였다. 본 실험을 통하여 치과용 모형재에 따른 3차원 디지털 모형의 정확도를 확인함으로써 임상 적용의 가능성을 평가하였으며, 제한된 조건 하에서 수행된 본 연구에서 다음과 같은 결론을 얻었다. 1. 치과용 백색광 스캐너를 사용하여 주 모형과 두 종류의 모형재로 제작한 작업모형을 3차원 디지털 모형으로 전환한 후, 선계측의 값을 비교한 결과 전체적인 계측지점에서 모두 모형재로 제작된 작업모형이 작게 계측되는 경향을 보였다. 2. 각 모형별 동일한 계측지점의 계측값의 차이가 있는지 알아보기 위해 paired t-test의 시행결과, 모든 계측지점에서 통계적으로 유의한 차이를 보였다(p<0.05). 결론적으로 두 가지 석고 모두 통계적으로 적정한 수준의 정확성을 나타내지 않았으나, 오차 수준이 선행연구에 비추어 볼 때 임상적으로 수용 가능한 수준이라 생각된다. 전악 인상채득을 통한 디지털 모형의 정확성은 검증이 되었으나, 스캔용(scannable)석고에 대한 임상 효용성을 판단하기 위해 타 제품과의 성분 분석 비교연구나 실질적인 보철물 제작을 통한 적합도 평가를 통해 CAD/CAM 보철물 제작 시장점을 부각할 수 있는 연구가 뒷받침되어야 할 것으로 사료된다.

Keywords

References

  1. Tinschert J, et al.: Marginal fit of alumina-and zirconia-based fixed partial dentures produced by a CAD/CAM system. Oper Dent 26: 367-374, 2001.
  2. Rekow ED: High-technology innovations and limitations for restorative dentistry. Dent Clin North Am 37: 513-524, 1993.
  3. Christensen GJ: Impressions are changing: deciding on conventional, digital or digital plus in-office milling. J Am Dent Assoc 140: 1301-1304, 2009.
  4. Beuer F, Schweiger J, Edelhoff D: Digital dentistry: an overview of recent developments for CAD/CAM generated restorations. Br Dent J 204: 505-511, 2008. https://doi.org/10.1038/sj.bdj.2008.350
  5. May KB, et al.: Precision of fit: the procera all-ceram crown. J Prosthet Dent 80: 394-404, 1993.
  6. Miyazaki T, et al.: A review of dental CAD/CAM: current status and future perspectives from 20 years of experience. Dent Mater J 28: 44-56, 2009. https://doi.org/10.4012/dmj.28.44
  7. Khalid AA, Ayman E: The effect of adding a stone base on the accuracy of working casts using different types of dental stones. J Contemp Dent Pract 7: 575-586, 2006.
  8. Anusavice KJ. Phillip's science of dental material. 11th ed. WB Saunders, Philadelphia, pp.621-654, 2003.
  9. Millstein PL: Determining the accuracy of gypsum casts made from Type IV dental stone. J Oral Rehabil 19: 239-243, 1992. https://doi.org/10.1111/j.1365-2842.1992.tb01098.x
  10. Moser JB, Stone DG, Willoughby GM: Properties and characteristics of resin die material. J Prosthet Dent 34: 297-304, 1975. https://doi.org/10.1016/0022-3913(75)90107-9
  11. Kasier DA, Nicholls JI: A study of distortion and surface hardness of improved artifical stone casts. J Prosthet Dent 36: 373-381, 1976. https://doi.org/10.1016/0022-3913(76)90157-8
  12. Linke BA, Nicholls JI, Faucher RR: Distortion analysis of stone casts made from impression materials. J Prothet Dent 54: 794-802, 1985. https://doi.org/10.1016/0022-3913(85)90473-1
  13. Gordon GE, Johnson Gh, Drennor DG: The effect of tray selection on the accuracy of elastomeric impression materials. J Prothet Dent 63: 12-15, 1990. https://doi.org/10.1016/0022-3913(90)90257-D
  14. Creed B, et al.: Comparison of the accuracy of linear measurement obtained from cone beam computerized tomography images and digital models. Semin Orthod 17: 49-56, 2011. https://doi.org/10.1053/j.sodo.2010.08.010
  15. American Dental Association: Council on dental materials, ANSI/ADA specification No. 25 for Dental Gypsum Products. Am Dent Assoc, Chicago, pp.640-644, 1987.
  16. Duke PD, et al.: Study of the physical properties of type IV gypsum, resin-containing and epoxy die materials. J Prosthet Dent 83: 466-473, 2000. https://doi.org/10.1016/S0022-3913(00)70043-6
  17. Delong R, et al.: Accuracy of a system for creating 3D computer models of dental arches. J Dent Res 90: 434-440, 2003.
  18. Christensen GJ: The state of fixed prosthodontics impressions: room for improvement. J Am Dent Assoc 136: 343- 346, 2006.
  19. Santoro M, et al.: Comparison of measurements made on digital and plaster models. Am J Orthod Dentofacial Orthop 124: 101-105, 2003. https://doi.org/10.1016/S0889-5406(03)00152-5
  20. Stevens DR, et al.: Validity, reliability, and reproducibility of plaster vs digital study models: comparison of peer assessment rating and Bolton analysis and their constituent measurements. Am J Orthod Dentofacial Orthop 129: 794-803, 2006. https://doi.org/10.1016/j.ajodo.2004.08.023
  21. Keating AP, et al.: A comparison of plaster, digital and reconstructed study model accuracy. J Orthod 35: 191-201, 2008. https://doi.org/10.1179/146531207225022626
  22. Quimby ML, et al.: The accuracy and reliability of measurements made on computer-based digital models. Angle Orthod 74: 298-303, 2004.
  23. Zilberman O, Huggare JA, Parikakis KA: Evaluation of the validity of tooth size and arch width measurements using conventional and three-dimensional virtual orthodontic models. Angle Orthod 73: 301-306, 2003.