Current Issue : October - December Volume : 2013 Issue Number : 4 Articles : 5 Articles
The aim of the study was to evaluate mechanical behavior of implants inserted in three substrates, by measuring the pullout strength and the relative stiffness. 32 implants (Master Porous-Conexao, cylindrical, external hexagon, and surface treatment) were divided into 4 groups (n=8): pig rib bone, polyurethane Synbone, polyurethane Nacional 40 PCF, and pinus wood. Implants were installed with the exact distance of 5?mm of another implant. The insertion torque (N�·cm) was quantified using the digital Kratos torque meter and the pullout test (N) was performed by an axial traction force toward the long axis of the implant (2?min/mm) through mount implant devices attached to a piece adapted to a load cell of 200?Kg of a universal testing machine (Emic DL10000). Data of insertion torque and maximum pullout force were submitted to one-way ANOVA and Bonferroni tests (a =0.05). Polyurethane Nacional 40 PCF and pinus wood showed the highest values of insertion torque and pullout force, with significant statistical difference (p< 0.05) with other groups. The analysis showed stiffness materials with the highest values for primary stability....
A case of implant-bone prosthetic rehabilitation, after the fracture of the maxillary central incisors, which had been treated with\r\ngrafting of a bone substitute, is reported. This case was followed by the normal procedures of implantology within the traditional\r\ntimeframe for bone regeneration. However, a barrier membrane was not used which shows that even along with the use of graft\r\nmaterial a sufficient amount of bone could be achieved for a subsequent rehabilitation. Therefore, after a five-year follow-up period,\r\nosseointegration was maintained with no marginal bone loss....
Despite the predictable longevity of implant prosthesis, there is an ongoing interest to continue to improve implant prosthodontic\r\ntreatment and outcomes. One of the developments is the application of computer-aided design and computer-aided manufacturing\r\n(CAD/CAM) to produce implant abutments and frameworks from metal or ceramic materials. The aim of this narrative review\r\nis to critically evaluate the rationale of CAD/CAM utilization for implant prosthodontics. To date, CAD/CAM allows simplified\r\nproduction of precise and durable implant components.The precision of fit has been proven in several laboratory experiments and\r\nhas been attributed to the design of implants. Milling also facilitates component fabrication from durable and aesthetic materials.\r\nWith further development, it is expected that the CAD/CAM protocol will be further simplified. Although compelling clinical\r\nevidence supporting the superiority of CAD/CAM implant restorations is still lacking, it is envisioned that CAD/CAM may become\r\nthe main stream for implant component fabrication....
Purpose. This in vitro study investigates how unilateral and bilateral occlusal loads are transferred to an implant assisted removable\r\npartial denture (IARPD). Materials and Methods. A duplicate model of a Kennedy class I edentulous mandibular arch was made\r\nand then a conventional removable partial denture (RPD) fabricated. Two Straumann implants were placed in the second molar\r\nregion, and the prosthesis was modified to accommodate implant retained ball attachments. Strain gages were incorporated into\r\nthe fitting surface of both the framework and acrylic to measure microstrain (??Strain).TheIARPD was loaded to 120Ns unilaterally\r\nand bilaterally in three different loading positions. Statistical analysis was carried out using SPSS version 18.0 (SPSS, Inc., Chicago,\r\nIL, USA) with an alpha level of 0.05 to compare the maximum ??Strain values of the different loading conditions. Results. During\r\nunilateral and bilateral loading the maximum ??Strain was predominantly observed in a buccal direction. As the load was moved\r\nanteriorly the ??Strain increased in the mesial area. Unilateral loading resulted in a twisting of the structure and generated a strain\r\nmismatch between the metal and acrylic surfaces. Conclusions. Unilateral loading created lateral and vertical displacement of the\r\nIARPD.The curvature of the dental arch resulted in a twisting action which intensified as the unilateral load was moved anteriorly....
A dental crown material,Nickel-Chrome-Molybdenum alloy, is manufactured using precision castingmethod froma polyurethane\r\nfoammodel in a regular and open-pore form, as a hard tissue implant for orthopedic applications.Thesamples produced have 10, 20,\r\nand 30 (�±3) pores per inch of pore densities and 0.0008, 0.0017, and 0.0027 g/mm3 densities, respectively. Samples were implanted\r\nin six dogs and observed for a period of two, four, and six months for the histopathological examinations.The dogs were examined\r\nradiologically in 15-day intervals and clinically in certain intervals. The implants were taken out with surrounding tissue at the end\r\nof these periods. Implants and surrounding tissues were examined histopathologically in terms of biocompatibility. As a result, it\r\nis seen that new bone tissue was formed, in pores of the porous implant at the head of the tibia in dogs implanted. Any pathology,\r\ninflammation, and reaction in old and new tissues were not observed. It was concluded that a dental alloy (Ni-Cr-Mo alloy) could\r\nalso be used as a biocompatible hard tissue implant material for orthopedics....
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