ИН-ВИТРО ЕВАЛУАЦИЈА НА ДЛАБОЧИНА И КВАЛИТЕТ НА ПРОСТОР ЗА КОЛЧЕТО ВО КОРЕНСКИОТ КАНАЛ КОРИСТЕЈЌИ ИНТРА ОРАЛЕН (ИОС) СПОРЕДЕНО СО ЛАБОРАТОРИСКИ СКЕНЕР
IN-VITRO EVALUATION OF DEPTH READING AND QUALITY OF POST SPACE IN THE ROOT CANAL USING INTRAORAL (IOS) COMPARED TO A LABORATORY SCANNERFOR CAD/CAMPOST AND CORE

Summary/Abstract: In everyday clinical practice we often meet patients who have residual (fractured or decayed) endodontically treated teeth that have lost or reduced coronary tooth structure, necessary for retention of future definitive restoration.Objectives: The purpose of this in-vitro study was to assess the depth and quality of the post space reading in the root canal using an intraoral (IOS), compared to a laboratory scanner.Matherials and Methods: To make the reference master model, we used a mandibular factory model (Study Model KaVoTM), with movable acrylic teeth. At 37 teeth we have cut the coronary part 2mm above the gingival part. Then, with a burr for preparation in the root part of the movable teeth, we prepared two channels with a length of 8 and 10mm. After preparing the space for the posts from the post and core of the master model, we proceeded to take a digital impression using a Medit intraoral scanner (IOS) and scan with a 3-D optical laboratory scanner (NeWay, Open Technologies, Rezzato, Italy), connected to a computer software (Exocad). With this procedure we created a virtual working model for making the first group of post and core/endocrown. We transferred the digital impression in the form of a stl file to the Dental CAD software of EXOCAD and made a virtual working model for making the second group of post and core/endocrown.We designed post and core/endocrown on the virtual models. Then, we superimposed the data from the scanned master model with a laboratory scanner in the form of STL-file with superposition with the data in the form of STL-file from the scanned master model with intraoral scanner so that the stay measurements are always between the same points. Then, we measured the depth and quality of the post space in the root channels of the virtual models with a digital measurement tool, comparing the results of both scanners with the results of the lengths of the fighters for the preparation of the post space of the master model.Results: The reading depth expressed in mm shows that the reading of the depth and quality of the post space in the root canal using intra oral (IOS) compared to a laboratory scanner has 40 to 50% higher values. In two cases the digital technique achieved less than a 30% difference compared to the actual length of the post space. Larger values were measured in the distal prepared space with a wider opening.Conclusions: In this in vitro study, the virtual dimensional analysis proved that using iOS reading space compared to a lab scanner has significantly better results, but there are still limitations to the reading depth for the narrow channels of the model, compared with the length of the dental burs for preparation with the help of a measuring instrument the micrometer screw indirectly with an accuracy of reading the measured value of 0.01 mm.

• Details
• Contents