Three dimensional accuracy analysis of dental stone casts fabricated using irreversible hydrocolloid impressions

알지네이트 인상체에서 제작된 치과용 석고 모형의 정확도에 대한 삼차원 디지털 분석

  • Joo, Young-Hun (Department of Prosthodontics, Daejeon Dental Hospital, Wonkwang University) ;
  • Lee, Jin-Han (Department of Prosthodontics, Daejeon Dental Hospital, Wonkwang University)
  • 주용훈 (원광대학교 대전치과병원 보철과) ;
  • 이진한 (원광대학교 대전치과병원 보철과)
  • Received : 2015.10.23
  • Accepted : 2015.12.03
  • Published : 2015.12.31


Purpose: The objects of this study was to evaluate the accuracy of the dental stone casts made from alginate impressions according to storage condition and stone pouring time. Materials and Methods: Each of upper and lower impressions of dental model was taken. The dental stone models were made immediately, 10, 30, 60, 180, 360 minutes after the impressions were taken at each storage condition. 3D models were constructed by scanning the stone model using 3D laser scanner. With Reference points, positioned on digital models, linear measurements of the dimensional change were compared by 3D metrology software, 3D average models were made and superimposition to identify the specific site of dimensional change and to measure surface deviation (mm). Results: Dental stone models which were made immediately after taking the impression showed the smallest linear dimensional change. As the stone pouring time was prolonged, the linear dimensional change was increased. More than 180 minutes after impression taking, linear dimensional change and surface distortion increased in the posterior molar region, regardless of the storage condition. Conclusion: For the optimum accuracy of the dental stone casts, alginate impression should be poured as soon as possible. If there were a need for storing, a humidor with 100% relative humidity must be used and be stored less than 180 minutes to fabricate the accurate dental model.


alginate impression;dimensional stability;3D superimposition


Supported by : 원광대학교


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