Qualitative and quantitative analysis of the tensions generated by metaloplastic fixed crowns, splinted and non-splinted, in the posterior region of the mandible, rehabilitated with regular and short implants, by digital image correlation method.
The use of dental implants in dentistry to restore function and aesthetics of partial edentulous patients has been increasing. In cases of severe vertical bone loss, especially in mandible's posterior areas, using short implants and reduced diameter associated with metaloplastic fixed crowns and united can be an alternative to bone graft surgery and better force transmission to the adjacent bone, respectively. Many methods have been used to verify tensions generated around the dental implants, however, the digital image correlation (DIC) has advantages as regards the possibility of evaluating the the tensions' dynamic in three dimensions (3D) and continuously using images taken over time, during occlusal loading. Due to low amount of studies that verify the stress distribution around the implant by the method of DIC, this study aims to evaluate qualitatively and quantitatively the biomechanical performance of splinted and non-splinted metaloplastic fixed crowns, screwed on cone Morse implants of different lengths positioned on the mandible posterior regions, by DIC method. Four photoelastic models (Araldite) will be made simulating a mandibular free end saddle, with the tooth 44 in resin (Luxatemp) and the teeth 45, 46 and 47 replaced by implants with 4 mm in diameter. Group 1 (G1) will be formed by two conventional length implants (11 mm; Titamax Cortical CM, Neodent) replacing the teeth 45 and 46, and one short implant (5 mm; Ws Cortical CM; Neodent) replacing 47. Group 2 (G2) will have one implant with 11 mm (45) and two implants with 5 mm (46 and 47). Group 3 (G3) will be rehabilitated by three implants of 5 mm and the group 4 (G4) for three implants of 11 mm in length. Splinted and non-splinted metaloplastic crowns will be screwed on the abutments. Different occlusal loads will be performed over the crowns: 100N in punctiform (45 mesial and 47 distal) and 150N in occlusal distributed. Surface tensions (horizontal [xx] and shear [xy]) will be calculated based on displacement and compared qualitatively and quantitatively by image correlation software (Davis 7.2, LaVision Inc.).
News published in Agência FAPESP Newsletter about the scholarship: