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Among the causes of tooth loss in dogs are the periodontal disease and trauma, particularly those caused by bites into hard objects, fights, falls and trampling, among others (Caiafa, 2007; Roza 2007). For absences of genetic background, Pavlica et al. (2001) identified hypodontia how the high prevalence among dogs.
The effective use of the implants was initiated by Branemark in 1960, when it began the development of an implant for the function that depended on clinical osseointegration, or anchoring in bone structural alive. This phenomenon has been difficult for methodological weaknesses to be proven at the time, since it was not possible to cut the implant without removing it from the bone. Therefore, it was not universally accepted until the 70's, when Schroeder and colleagues have, with newly developed techniques to time, perform the procedure (Albrektsson et al., 2005).
Regarding factors that influence the osseointegration of the implant, Albrektsson et al. (1981) related 1) the biocompatibility, 2) the design of the implant, 3) conditions of the implant surface, 4) the surgical site, 5) the surgical technique for fixing the implant, and 6) the loading conditions applied on the implant after its installation.
The two main prerequisites for proper treatment involving implants is the careful preoperative examination and a complete planning of treatment. In part, the result also depends on the patient's medical conditions, but also the integrity of local and bone morphology of the area selected for the installation of the implant. The positioning and direction of the implants should be designed to create the best possible function and aesthetics (Lekholm, 2004).
Since the beginning of its use, the implants have been modified in order to obtain better performance in surgery and prosthetics restoration. The goal of research in biomaterials has been and remains the development of materials that induce healing predictable, controlled, guided and rapidly to the tissue interfaces (Brunski et al., 2000).
Endosseous implants are usually made of commercially pure titanium, a reactive metal that on exposure to air forms titanium oxide on its surface offering a corrosion resistant. The threaded portion of the implant offers a larger surface area for engaging the bone to provide initial stability of the implant. Secondary stability is achieved by osseointegration in which bone directly contacts the implant surface. Treatment of the implant surface (with sand blasting and/or acid etching) within a surface roughness range of 1-2μm has been shown to increase the rate of osseointegration thereby improving early stability of the implant. This improvement is thought to be due to a combination of factors, including increasing the surface area of the implant for integration to occur, modulating cellular activity to promote migration and differentiation of osteoblasts, and to improve fibrin adhesions and stabilization of the blood clot. Alterations in surface morphology through acid etching provides a bioactive surface with good wettability through increased surface area and protein absorption. There is increased adsorption of fibrinogen and concentration of complement factor 3. There is early bone apposition onto its surface with increased bone to implant contact (Abrahamsson et al. 2004, Caiafa, 2007). Further improvements to the rate of osseointegration may be obtained by altering the surface chemistry of the implant surface (Buser et al. 2000).
In selecting a system of implants in particular, one should bear in mind a number of factors such as the site of implantation and the underlying anatomy, need for graft, bone quality and design of the prosthetic component. Understanding it and using the biomechanical theories that affect the design of the endosseous implant, you can increase the success of these implants in various loading conditions (Lee et al., 2005).
Until few months ago there was not another method for diagnosis and planning the installation of dental implants in dogs that were not the intra-oral radiography, when Roza et al. (2008) standardized cone beam computed tomography (CBCT) as the method of choice for this type of examination.
The CBCT is a diagnostic mode where the system tube-detector X-ray holds a spin of the 360th around the patient's head and capture images that will be analyzed in specific software (Garib et al., 2002; Scarfe et al., 2006). One of its advantages is that the specific software for the reconstruction of the images can be installed on common computers, no need for a workstation coupled to tomography, reducing costs and space (Scarfe et al., 2006).
To evaluate the bone structure, the cone beam computed tomography measurements and allows simulation of the implant, facilitating thus the choice of the appropriate size implant to the patient, minimizing thus the risk of injury or bone trepanation of the mandibular canal. In human dentistry, many studies referred the CBCT as a gold standard for this purpose (Iplikçioglu et al., 2002; Guerrero et al., 2006).
Since the patient is under general anesthesia, the established protocol starts with gingival incision of the bone height, and soft tissue clearance. The drilling sequence is done, always with abundant water, and at max speed of 1500rpm (Lekholm, 2005), with spherical bur, and proceeding with the sequential burs, 2mm cylindrical bur, that determines the height and width of the implant, pilot bur, that makes the transition from 2 to 3mm, and 3mm cylindrical bur always with caution regarding deepness reference of the burs in relation to the top of the bone height. Having determined the height and width of the drill the counter sink bur is used, that gives it the format of the top of the implant, followed by the making of the screw (for type 1 bone) and the placement of the implant, connected to the reduction contra angle, at the speed of 15-20rpm, with maximum initial stability. The implant should be locked with a force of 20-25 Newtons (N) for procedures where osseointegration is expected, and 45 N for implants submitted to immediate load (Lorenzoni et al, 2003, Roza et al., 2007).
The postoperative period is to antibiotics and pain control. The owner of the dog should be directed to the needs of post-operative, as proper oral hygiene. The techniques used to install dental implants in humans can used in dogs, with some modifications. The choice of adequate implant is fundamental in the success of the procedure.
The technique described is safe to execute with the proper instruments and equipment and has shown to be effective in implants submitted to immediate load in dogs, therefore being eligible for routine dentistry in dogs.
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