Gary Hack1, Leila Liberman2, Kirstin Vach3, Joerg P Tchorz4, Ralf J Kohal5, Sebastian B M Patzelt6. 1. Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD, USA. 2. Central Texas Veterans Health Care System, Temple, TX, USA. 3. Institute for Medical Biometry and Statistics, Faculty of Medicine and, Medical Center, University of Freiburg, Germany. 4. Department of Operative Dentistry, Periodontology, and Endodontology, University of Dental Medicine and Oral Health, Danube Private University, Krems, Austria. 5. Department of Prosthetic Dentistry, Center for Dental Medicine, Medical Center - University of Freiburg, Freiburg, Germany. 6. Department of Prosthetic Dentistry, Center for Dental Medicine, Medical Center - University of Freiburg, Freiburg, Germany. Electronic address: sebastian@patzelt.dental.
Abstract
PURPOSE: Within the specialty of prosthodontics, oral impressions are ubiquitous tools utilized to transfer intraoral characteristics such as teeth, implants, and soft tissue into a physical state (stone cast) that is processable in a laboratory setting for the fabrication of dental restorations. In recent years, optical impression systems have become ubiquitous in clinical practice replacing the conventional method of impression making. The purpose of the present study was to evaluate the feasibility and accuracy of computerized optical impression making of edentulous jaws in an in vivo setting. METHODS: 29 edentulous patients (27 maxillae and five mandibles) underwent conventional impressions as well as computerized optical impressions. The conventional impressions and the resulting stone casts were digitized and superimposed over the computerized/digitized optical impressions in order to obtain information on differences between the two datasets. Statistical analyses were performed to identify relevant deviations. RESULTS: The overall mean difference between the stone cast, digital scans and the computerized optical scans were 336.7 ± 105.0 µm (n = 32), 363.7 ± 143.1 µm (n = 24), and 272.1 ± 168.5 µm (n = 29), respectively. The visual evaluations revealed highest deviations (≥ 500 µm) in the areas of the soft palate, the sublingual areas, and the vestibule (peripheral seal zone). CONCLUSIONS: Within the limitations of the present study, the investigated scanners were not able currently to fully replace a conventional impression for the fabrication of a complete denture.
PURPOSE: Within the specialty of prosthodontics, oral impressions are ubiquitous tools utilized to transfer intraoral characteristics such as teeth, implants, and soft tissue into a physical state (stone cast) that is processable in a laboratory setting for the fabrication of dental restorations. In recent years, optical impression systems have become ubiquitous in clinical practice replacing the conventional method of impression making. The purpose of the present study was to evaluate the feasibility and accuracy of computerized optical impression making of edentulous jaws in an in vivo setting. METHODS: 29 edentulouspatients (27 maxillae and five mandibles) underwent conventional impressions as well as computerized optical impressions. The conventional impressions and the resulting stone casts were digitized and superimposed over the computerized/digitized optical impressions in order to obtain information on differences between the two datasets. Statistical analyses were performed to identify relevant deviations. RESULTS: The overall mean difference between the stone cast, digital scans and the computerized optical scans were 336.7 ± 105.0 µm (n = 32), 363.7 ± 143.1 µm (n = 24), and 272.1 ± 168.5 µm (n = 29), respectively. The visual evaluations revealed highest deviations (≥ 500 µm) in the areas of the soft palate, the sublingual areas, and the vestibule (peripheral seal zone). CONCLUSIONS: Within the limitations of the present study, the investigated scanners were not able currently to fully replace a conventional impression for the fabrication of a complete denture.