Advanced search
Start date

"Influence of tray on accuracy of impression using parallel implants in a model Cad-Cam: a comparison in vitro"

Grant number: 11/12717-1
Support type:Scholarships in Brazil - Scientific Initiation
Effective date (Start): March 01, 2012
Effective date (End): December 31, 2012
Field of knowledge:Health Sciences - Dentistry - Dental Materials
Principal researcher:Francisco de Assis Mollo Júnior
Grantee:Camila Cruz Lorenzetti
Home Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil


One of the reasons of failure of the implant-prosthesis is the lack of precision in the adaptation of the system, which confirms the need to obtain a model of faithful work. This process is dependent on such factors as the type of impression material, the technical transfer of prosthetic components and the type of tray used. The precision molding is further expected to CAD / CAM technology, which evaluates the entire surface of the working model in three dimensions, detecting any irregularities between the preparation and the original plaster model, which favors the reliability of the work for making of custom abutments. Any inaccuracy in transferring the dimensional positioning of the implants or abutments for the models of work will result in failure of the prosthesis, thus requiring an impression as perfect as possible. A molding material must be rigid enough to avoid displacement of the transferees for the application of force to remove. At the same time, the union of transferees with square bar steel and acrylic resin is an attempt to stabilize the transferees against rotation and improve the precision of adaptation. The type of tray as well as the material it is made directly interferes with the stability of the impression material. The stock trays suffer less distortion compared to the plastic trays and are frequently used in routine clinical work. Thus, given the need to obtain comparisons of standards and reliable models, the objective of this study is to evaluate the influence of the tray on the dimensional accuracy of impressions for implants parallel models in CAD - CAM in standardized laboratory conditions.