Influence of periodontal tissue thickness on buccal plate remodelling on immediate implants with xenograft.

AIM: To evaluate the influence of gingival thickness and bone grafting on buccal bone plate remodelling after immediate implant placement in sockets with thin buccal bone, using a flapless approach. MATERIALS AND METHODS: The gingiva of eight dogs was thinned at one side of the mandible, mandibular premolars were extracted without flaps, and four implants were installed on each side at 1.5 mm from the buccal bone. The sites were randomly assigned into: TG (test group) = thin gingiva; TG + GM (TG with grafting material); CG (control group) = normal gingiva; and CG + GM (CG with grafting material). After 12 weeks the dogs were sacrificed and the samples were processed for histological analysis. RESULTS: All animals exhibited a thin buccal bone initially. In all the experimental groups the buccal gap was filled with newly formed bone and the buccal bone level was slightly apical to the implant shoulder. There were no statistically significant differences among the groups for the histomorphometric parameters. CONCLUSIONS: The thickness of the buccal bone was a fundamental factor in buccal bone plate resorption, even with flapless implantation. The gingival thickness or the addition of a biomaterial in the gap did not influence the results.

The influence of the periodontal biotype on peri-implant tissues around immediate implants with and without xenografts. Clinical and micro-computerized tomographic study in small Beagle dogs.

OBJECTIVE: Soft tissues and buccal bone plate remodeling after immediate implantation in sockets with thin buccal bone, using the flapless approach with or without bone graft into the buccal gap, was compared between sites with thin and normal gingiva. MATERIAL AND METHODS: Eight dogs had the gingiva of one side of the mandible thinned, the mandibular premolars were extracted without flaps, and 4 implants were installed in each side, positioned 1.5 mm from the buccal bone. The sites were randomly assigned into: TG (test group) = thin gingiva; TG + GM (TG with grafting material); CG (control group) = normal gingiva; and CG + GM (CG with grafting material). Buccal bone thickness (BBT), thickness of keratinized tissue (TKT), alveolar thickness (AT), gingival recession (GR), and probing depth (PD) were clinically evaluated. Within 12 weeks the dogs were sacrificed and the samples were analyzed by micro-computerized tomography. RESULTS: A thin BBT was observed in all the dogs. The presurgical procedures reduced TKT in the test group, with minimal changes of the AT. There were no statistically significant differences among the groups for the clinical parameters and the tomographic analysis showed similar linear and tri-dimensional bone reduction in all the groups. CONCLUSION: The thickness of the buccal bone was a fundamental factor in buccal bone plate resorption, even with flapless implantation. The decrease in gingival thickness or the addition of a biomaterial in the gap did not influence the results.

Buccal bone plate remodeling after immediate implants with or without synthetic bone grafting and flapless surgery: a histomorphometric and fluorescence study in dogs.

OBJECTIVE: The aim of this study was to evaluate the buccal bone plate remodeling after immediate implantation using the flapless approach with or without bone graft into the gap between the implant and the buccal bone. MATERIAL AND METHODS: Eight dogs had the mandibular bicuspids extracted without flaps, and four implants were installed on each side, totaling eight implants per animal. Randomly, in one side, the implants were positioned at the bone crest level (equicrestal), and on the opposite side, the implants were positioned 2 mm subcrestal. All the implants were positioned 2.0 mm from the buccal bone plate (gap) and associated or not with grafting material. Therefore, the following treatments were performed: implants subcrestal test (SCTG) with bone graft and control (SCCG) without bone graft, and equicrestal test (ECTG) with bone graft and control (ECCG) without bone graft. One week following the surgeries, metallic prostheses were installed. Bone markers were administered 1, 2, 4, and 12 weeks after implant placement for fluorescence analysis. Ground sections were prepared from 12-week healing biopsies, and histomorphometry was performed. RESULTS: The histomorphometric evaluation presents significant better results for the ECTG in the vertical crestal bone resorption, but the other parameters showed better results for the SCCG. The fluorescence evaluation in adjacent areas showed numerically different results between groups with a small decrease at 12 weeks, except for the SCCG, which was higher at this time. The distant area showed a continuous increase in the marked bone. CONCLUSION: The equicrestally placed implants presented little or no loss of the buccal bone wall. The subcrestally positioned implants presented loss of buccal bone, regardless of the use of bone graft. However, the buccal bone was always coronal to the implant shoulder. Both the equicrestal and subcrestal groups were benefited in the early stages of bone healing as evidenced by the fluorescence analysis.

Buccal bone plate remodeling after immediate implant placement with and without synthetic bone grafting and flapless surgery: radiographic study in dogs.

Recent studies in animals have shown pronounced resorption of the buccal bone plate after immediate implantation. The use of flapless surgical procedures prior to the installation of immediate implants, as well as the use of synthetic bone graft in the gaps represent viable alternatives to minimize buccal bone resorption and to favor osseointegration. The aim of this study was to evaluate the healing of the buccal bone plate following immediate implantation using the flapless approach, and to compare this process with sites in which a synthetic bone graft was or was not inserted into the gap between the implant and the buccal bone plate. Lower bicuspids from 8 dogs were bilaterally extracted without the use of flaps, and 4 implants were installed in the alveoli in each side of the mandible and were positioned 2.0 mm from the buccal bone plate (gap). Four groups were devised: 2.0-mm subcrestal implants (3.3 × 8 mm) using bone grafts (SCTG), 2.0-mm subcrestal implants without bone grafts (SCCG), equicrestal implants (3.3 × 10 mm) with bone grafts (ECTG), and equicrestal implants without bone grafts (ECCG). One week following the surgical procedures, metallic prostheses were installed, and within 12 weeks the dogs were sacrificed. The blocks containing the individual implants were turned sideways, and radiographic imaging was obtained to analyze the remodeling of the buccal bone plate. In the analysis of the resulting distance between the implant shoulder and the bone crest, statistically significant differences were found in the SCTG when compared to the ECTG (P = .02) and ECCG (P = .03). For mean value comparison of the resulting linear distance between the implant surface and the buccal plate, no statistically significant difference was found among all groups (P > .05). The same result was observed in the parameter for presence or absence of tissue formation between the implant surface and buccal plate. Equicrestally placed implants, in this methodology, presented little or no loss of the buccal bone. The subcrestally positioned implants presented loss of buccal bone, even though synthetic bone graft was used. The buccal bone, however, was always coronal to the implant shoulder.

Influence of interimplant distances and placement depth on peri-implant bone remodeling of adjacent and immediately loaded Morse cone connection implants: a histomorphometric study in dogs.

OBJECTIVES: The aim of this study was to histomorphometrically evaluate the influence of interimplant distances (ID) and implant placement depth on bone remodeling around contiguous Morse cone connection implants with 'platform-shifting' in a dog model. MATERIAL AND METHODS: Bilateral mandibular premolars of six dogs were extracted, and after 12 weeks, each dog received 8 implants, four placed 1.5 mm subcrestally (SCL) on one side of the mandible and four placed equicrestally (ECL) on the other side, alternating the ID of 2 and 3 mm. The experimental groups were SCL with IDs of 2 mm (2 SCL) and 3 mm (3 SCL) and ECL with IDs of 2 mm (2 ECL) and 3 mm (3 ECL). Metallic crowns were immediately installed. After 8 weeks, the animals were euthanized and histomorphometric analyses were performed to compare bone remodeling in the groups. RESULTS: The SCL groups' indices of crestal bone resorption were significantly lower than those of ECL groups. In addition, the vertical bone resorption around the implants was also numerically inferior in the SCL groups, but without statistical significance. No differences were obtained between the different IDs. All the groups presented similar good levels of bone-to-implant contact and histological bone density. CONCLUSION: The subcrestal placement of contiguous Morse cone connection implants with 'platform shifting' was more efficient in preserving the interimplant crestal bone. The IDs of 2 and 3 mm did not affect the bone remodeling significantly under the present conditions.

The relationship between interimplant distances and vascularization of the interimplant bone.

BACKGROUND: Long-term success of the implant restorations is based upon the biology and vasculature of the bone surrounding the implants, especially for the bone between two implants. PURPOSE: The aim of this study was to evaluate how loaded implants placed 2 or 3 mm apart influence bone vessel organization. MATERIAL AND METHODS: Six mongrel dogs were used for the study. The four mandibular premolars were extracted and 3 months later, four 4.5 x 10 mm implants were placed on each side of the mandible. The implants were placed so that two adjacent implants were 2 mm (group 1) or 3 mm (group 2) distant from each other. After 12 weeks, the implants were loaded with provisional prostheses, then metallic crowns were placed 4 weeks later. Both temporary and metallic restorations were made so that the distance between the contact point and the bone crest was 5 mm. The animals were sacrificed after 8 weeks. The hemi-mandibles were removed and prepared for analysis. The interimplant bone vasculature of the two groups was studied using scanning electron microscopic images fractal analysis. The fractal dimension (D(f)) was calculated using the box-counting method. RESULTS: The values of the D(f) for the blood vessels were significantly higher (P<.05) in the specimens of the group 2 (1.969+/-0.169) than the group 1 (1.556+/-0.246). CONCLUSION: The presence of more blood vessels in the group 2 is another indication that 3 mm is a preferable distance for contiguous implants than the 2 mm distance.

Bone remodeling adjacent to Morse cone-connection implants with platform switch: a fluorescence study in the dog mandible.

PURPOSE: The aim of this study was to evaluate, through fluorescence analysis, the effect that different interimplant distances, after prosthetic restoration, will have on bone remodeling in submerged and nonsubmerged implants restored with a "platform switch." MATERIALS AND METHODS: Fifty-six Ankylos implants were placed 1.5 mm subcrestally in seven dogs. The implants were placed so that two fixed prostheses, with three interimplant contacts separated by 1-mm, 2-mm, and 3-mm distances, could be fabricated for each side of the mandible. The sides and the positions of the groups were selected randomly. To better evaluate bone remodeling, calcein green was injected 3 days before placement of the prostheses at 12 weeks postimplantation. At 3 days before sacrifice (8 weeks postloading), alizarin red was injected. The amounts of remodeled bone within the different interimplant areas were compared statistically before and after loading in submerged and nonsubmerged implants. RESULTS: Statistically significant differences existed in the percentage of remodeled bone seen in the different regions. Mean percentages of remodeled bone in the submerged and nonsubmerged groups, respectively, were as follows: for the 1-mm distance, 23.0% +/- 0.05% and 23.1% +/- 0.03% preloading and 27.0% +/- 0.03% and 25.2% +/- 0.04% postloading; for the 2-mm distance, 18.2% +/- 0.05% and 18.1% +/- 0.04% preloading and 21.3% +/- 0.07% and 19.9% +/- 0.03% postloading; for the 3-mm distance, 18.3% +/- 0.03% and 18.3% +/- 0.03% preloading and 18.8% +/- 0.04% and 19.8% +/- 0.04% postloading; for distal-extension regions, 16.6% +/- 0.02% and 17.4% +/- 0.04% preloading and 17.0% +/- 0.04% and 18.4% +/- 0.04% postloading. CONCLUSIONS: Based upon this animal study, loading increases bone formation for submerged or nonsubmerged implants, and the interimplant distance of 1 mm appears to result in more pronounced bone remodeling than the 2-mm or 3-mm distances in implants with a "platform switch."

Replacement of hopeless retained primary teeth by immediate dental implants: a case report.

Hopeless retained primary teeth without permanent successors represent a restorative challenge for clinicians, along with esthetic and functional problems for patients. While various treatment approaches for congenitally missing teeth have been proposed, the replacement of a missing tooth with a dental implant offers specific advantages, such as preservation of the alveolar crest and elimination of the need to restore the adjacent teeth, over other options for tooth replacement. The aim of this article was to illustrate the surgical and prosthetic treatment with implants of a patient with primary teeth without permanent successors.

Influence of interimplant distances and placement depth on papilla formation and crestal resorption: a clinical and radiographic study in dogs.

Among the factors that contribute to the papilla formation and crestal bone preservation between contiguous implants, this animal study clinically and radiographically evaluated the interimplant distances (IDs) of 2 and 3 mm and the placement depths of Morse cone connection implants restored with platform switch. Bilateral mandibular premolars of 6 dogs were extracted, and after 12 weeks, the implants were placed. Four experimental groups were constituted: subcrestally with ID of 2 mm (2 SCL) and 3 mm (3 SCL) and crestally with ID of 2 mm (2 CL) and 3 mm (3 CL). Metallic crowns were immediately installed with a distance of 3 mm between the contact point and the bone crest. Eight weeks later, clinical measurements were performed to evaluate papilla formation, and radiographic images were taken to analyze the crestal bone remodeling. The subcrestal groups achieved better levels of papillae formation when compared with the crestal groups, with a significant difference between the 3 SCL and 3 CL groups (P = .026). Radiographically, the crestal bone preservation was also better in the subcrestal groups, with statistically significant differences between the 2SCL and 2CL groups (P = .002) and between the 3SCL and 3CL groups (P = .008). With the present conditions, it could be concluded that subcrestal implant placement had a positive impact on papilla formation and crestal bone preservation, which could favor the esthetic of anterior regions. However, the IDs of 2 and 3 mm did not show significantly different results.

Optimization in multi-implant placement for immediate loading in edentulous arches using a modified surgical template and prototyping: a case report.

Immediate loading of dental implants shortens the treatment time and makes it possible to give the patient an esthetic appearance throughout the treatment period. Placement of dental implants requires precise planning that accounts for anatomic limitations and restorative goals. Diagnosis can be made with the assistance of computerized tomographic scanning, but transfer of planning to the surgical field is limited. Recently, novel CAD/CAM techniques such as stereolithographic rapid prototyping have been developed to build surgical guides in an attempt to improve precision of implant placement. The aim of this case report was to show a modified surgical template used throughout implant placement as an alternative to a conventional surgical guide.

The effects of interimplant distances on papilla formation and crestal resorption in implants with a morse cone connection and a platform switch: a histomorphometric study in dogs.

BACKGROUND: Implant esthetics have been the focus of attention for the last few years, and one of the most important points is the effect that interimplant distances can have on papilla formation and bone loss. The aim of this study was to evaluate the effect that distances of 1, 2, and 3 mm between implants after prosthetic restoration will have on crestal bone resorption (from the top of the implant to the bone crest [TI-BC]) and bone resorption (from the top of the implant to the first bone-to-implant contact TI-BIC) in two-stage implants used in a submerged and non-submerged protocol. METHODS: The mandibular bilateral premolars of seven dogs were extracted, and after 12 weeks, each dog received eight implants. The implants were placed so that three interimplant contact points were created, with 1-mm (group 1), 2-mm (group 2), and 3-mm (group 3) distances constructed on each side. The sides and the position of the groups were randomly selected. After 12 weeks, the implants received metallic prostheses with 5 mm between the contact point and the bone crest. After 8 weeks more, the animals were sacrificed. RESULTS: The TI-BC was 0.20 and 0.18 mm for group 1, 0.15 and 0.14 mm for group 2, and 0.15 and 0.15 mm for group 3 for non-submerged and submerged implants, respectively. At the proximal region, the TI-BC was 0.16 mm for non-submerged and 0.16 mm for submerged implants. The TI-BIC was 0.32 and 0.30 mm for group 1, 0.19 and 0.21 mm for group 2, and 0.30 and 0.24 mm for group 3 for non-submerged and submerged implants, respectively. At the proximal region, the TI-BIC was 0.26 mm for non-submerged and 0.25 mm for submerged implants. There was no statistical difference for any of the parameters (analysis of variance [ANOVA]). CONCLUSION: Distances of 1, 2, and 3 mm between implants do not result in statistically significant differences on TI-BC and TI-BIC around submerged or non-submerged implants with a Morse cone connection and a platform switch.

Preprosthetic periodontal surgery in the proximal area with modification of the col area: results following the reestablishment of the contact point.

BACKGROUND: Anatomic characteristics of interproximal areas are dependent on the anatomy, position, and proximal contact of adjacent teeth. The objective of this study was to investigate the influence of the reestablishment of the interproximal contact following the restorative alveolar interface (RAI) procedure on the interproximal gingival COL and formation of the interdental gingival papilla. METHODS: Six mongrel dogs received bilateral apically positioned flaps, crown lengthening, and the RAI procedure on the maxillary fourth bicuspid and first molar. After 2 weeks, in a randomized manner, one side was prepared to receive metallic crowns and the opposite side remained as the control. The crowns were cemented at the 4-week postoperative period, and the dogs were sacrificed after another 4 weeks, totaling a period of 4 weeks with the full crowns in position and a total of 8 postoperative weeks. Histologic specimens were stained with hematoxylin and eosin and Mallory dyes. Sections 6 micro m thick were obtained in a bucco-lingual plane allowing ample visualization of the interproximal area. RESULTS: Clinical measurements revealed that, in the restored sides, four animals had complete fill of the interdental spaces with gingival papilla, whereas the other two dogs had a distance from the contact point to the tip of papilla varying from 0.02 to 0.021 mm. In the control group, papillae were totally reepithelialized with keratinized epithelium and a convex form. The epithelium completely covered the connective tissue and showed both epithelial projections and surface desquamation. On the test group, despite the presence of the prosthesis, the COL morphology modified by preprosthetic surgery was not altered, presenting a convex papilla with a triangular form and with a keratinized epithelium. Additional histologic characteristics were the same as found in the control group. CONCLUSION: Based on the results of this study, the reestablishment of the contact point does not revert what was obtained with the RAI procedure; the interproximal tissues remain convex and keratinized.

Influence of interimplant distance on papilla formation and bone resorption: a clinical-radiographic study in dogs.

Implant esthetics has been the focus of attention for the past decade, and one vital issue is the effect of interimplant distance on interimplant papilla formation and crestal bone loss. The aim of this study was to evaluate the effect of 1, 2, and 3 mm of interimplant distance on papilla formation and crestal resorption in submerged and nonsubmerged Ankylos implants after prosthetic restoration. Bilateral mandibular premolars of 7 dogs were extracted, and after 12 weeks each dog received 8 implants. Implants were placed so that 3 interimplant distances were created at 1 mm (group 1), 2 mm (group 2), and 3 mm (group 3). The sides and the position of the groups were randomly selected. Twelve weeks after placement, the implants received metallic prostheses that allowed 5 mm of space between the prosthetic contact point (CP) and the crestal bone (CB). After 8 weeks, the distance between the CP and the papilla (CP-P) and the gingival height at the distal proximal aspect of the prosthesis (CP-DE) was clinically measured. Radiographic images were obtained to measure the distance of the CP to the CB within the interimplant surfaces (CP-IP) and adjacent to the edentulous surfaces (CP-ED). The clinical measurement of CP-P for submerged and nonsubmerged implants was 3.57+/-1.17 mm and 3.10+/-0.82 mm for group 1, 3.57+/-0.78 mm and 3.16+/- 0.87 mm for group 2, and 3.35+/- 0.55 mm and 3.07+/-0.93 mm for group 3. The CP-DE was 3.25+/-0.77 mm for submerged and 2.78+/- 0.64 mm for nonsubmerged implants. The CP-IP for the submerged and nonsubmerged implants was 6.91+/-0.95 mm and 7.68+/-2.73 mm for group 1, 7.46+/-1.43 mm and 5.87+/-1.71 mm for group 2, and 7.72+/-0.81 mm and 7.59+/-1.33 mm for group 3. The CP-ED was 6.77+/-1.33 mm for submerged implants and 6.03+/-1.58 mm for nonsubmerged implants. There were no statistical significant differences for any of the measured parameters. We conclude that when the distance from the CP to the CB was 5 mm, interimplant distances of 1 to 3 mm did not affect papilla formation or crestal resorption of submerged or nonsubmerged implants in the dog model.

Immediate implant in extraction socket with acellular dermal matrix graft and bioactive glass: a case report.

A buccal plate destroyed as a result of a longitudinal root fracture was completely restored by the use of a Frialit-2 implant placed in the alveolus of the fractured maxillary left first bicuspid. An acellular dermal matrix material was used as a membrane barrier to cover the implant, and a bioactive glass was used as grafting material. After 6 months, the defect around the implant was completely filled by mineralized tissue.

Aumento da espessura do rebordo ósseo com um novo enxerto sintético particulado. Caso clínico com avaliação microtomográfica / Horizontal alveolar ridge augmentation with a new particulate bone substitute: a case report with micro-CT evaluation

As limitações anatômicas do rebordo alveolar residual podem impedir a instalação de um implante osseointegrado. Nesses casos, procedimentos de regeneração óssea guiada são necessários para proporcionar osso alveolar suficiente em altura e/ou espessura para a inserção de implantes dentais. Este relato piloto de caso clínico apresenta um procedimento de aumento horizontal do rebordo ósseo usando um novo substituto ósseo aloplástico para proporcionar volume ósseo necessário para a colocação de um implante, avaliando também por meio de microtomografia o osso neoformado. O paciente do sexo masculino, 58 anos, não fumante, sem condições sistêmicas que pudessem afetar o procedimento cirúrgico, apresentava a ausência de um dente (primeiro pré-molar superior direito) e optou por instalar um implante para a reabilitação cirúrgico-protética desta área. A tomografia computadorizada pré-operatória mostrou que o osso residual tinha espessura insuficiente para a instalação de um implante, sendo necessária a realização de um procedimento cirúrgico para aumento ósseo horizontal. O paciente assinou um consentimento informado autorizando a realização dos procedimentos bem como a documentação científica do caso. Foi realizada cirurgia de regeneração óssea guiada (ROG) utilizando substituto ósseo particulado (Reprobone®) e uma membrana colágena (Biomend), para aumentar a espessura óssea vestíbulo-palatal. O paciente foi apropriadamente medicado e a cicatrização ocorreu sem intercorrências. Após 6 meses, a área foi reaberta e antes da instalação do implante uma biópsia óssea foi coletada para análise microtomográfica. A técnica de ROG proporcionou volume ósseo adequado para a colocação do implante. A análise microtomográfica da biópsia óssea resultou em 40,85% de volume ósseo cortical e 17,08% de biomaterial residual...

Anatomic limitations of the residual alveolar bone may impair implant placement. Alveolar ridge augmentation procedures are required in such cases to provide alveolar bone width and/or height for dental implant placement. This case report presents a horizontal ridge augmentation procedure using a new alloplastic bone substitute providing bone volume for implant placement, with micro-CT analysis of the newly formed bone. The patient was a 58-year-old male, non-smoker, with no systemic health conditions that could affect the surgical procedure, and reported the willingness of rehabilitating the edentulous area corresponding to the tooth 14 with an osseointegrated implant. The CBCT analysis revealed that residual alveolar bone width was too narrow for implant insertion, and therefore a bone augmentation procedure was necessary. The patient signed an informed consent form authorizing all procedures and scientific documentation. Guided bone regeneration was performed using ReproBone® granules and a collagen membrane (BioMend®) to increase the buccal-palatal bone width. The patient was properly medicated and healing was uneventful. After 6 months, the area was reopened and before placing an implant a bone biopsy was collected for micro-CT analysis. The bone augmentation procedure provided adequate bone volume for implant placement. The micro-CT results of the bone biopsy showed 40% of bone volume and 17% of remnant particles of the biomaterial after 6 months. It was concluded that this biomaterial may be used in such clinical situations as an alternative to autogenous bone blocks and still avoiding patient morbidity...

Desenvolvimento de bases ósseas padronizadas para avaliação da estabilidade primária de implantes / Development of standardized bone specimens to evaluate primary stability of dental implants

A qualidade óssea do sítio receptor é considerada um dos fatores relevantes para o sucesso de implantes orais. O objetivo deste estudo piloto foi avaliar comparativamente cilindros ósseos de origem suína, de alta e baixa densidades, em modelo in vitro, por meio de análises bidimensional (radiografia digital) e tridimensional (tomografia computadorizada). Os cilindros ósseos foram preparados a partir de osso suíno, retirados do côndilo mandibular ou da cabeça do fêmur, e separados em dois grupos: grupo A: cilindros removidos da cabeça do fêmur (alta densidade óssea); grupo B: cilindros removidos do côndilo mandibular (baixa densidade óssea). Para a certificação dos cilindros (análise 2D) foram realizadas tomadas radiográficas digitais para determinar a densidade radiográfica. Foram realizadas ainda análises tridimensionais, por meio de tomografias computadorizadas, avaliando os seguintes parâmetros tomográficos: área óssea do cilindro, volume ósseo do cilindro, densidade óssea tridimensional, volume total do espaço de poros, porcentagem da porosidade total. O teste t Student foi utilizado para verificar a significância da diferença entre os grupos A e B; em todas as análises foi considerado nível de significância de 5%. Os resultados da análise 2D dos blocos ósseos mostraram que a diferença entre os grupos A e B foi estatisticamente significante (p < 0,0001). As diferenças entre os grupos A e B também foram estatisticamente significantes para todos os parâmetros tomográficos avaliados (p < 0,05). Concluiu-se que a metodologia apresentada gera cilindros ósseos padronizados de alta e baixa densidades, que poderão ser utilizados em estudos futuros para avaliar comparativamente a estabilidade inicial de implantes.

Bone quality is one of most important factors for the success of dental implants. The purpose of this study was to comparatively evaluate porcine bone cylinders, of high and low bone density, using 2D- (digital radiograph) and three-dimensional (computerized tomography) analysis. Bone cylinders were prepared from porcine bone, removed from mandibular condyle or from the femur head, and separated in two groups: Group A: cylinders removed from femur head (high bone density), and Group B: cylinders removed from mandibular condyle (low bone density). Digital radiographs were taken for the certification of bone cylinders (2D analysis), to determine the radiographic bone density. Using computerized tomograms, tri-dimensional analysis were made, evaluating the following tomographic parameters: cylinder bone area, cylinder bone volume, tridimensional bone density, total volume of porosity, total percentage of porosity. The Student´s t test was used to verify the significance of differences between groups A and B (at 5% level). The results showed that for 2D analysis of bone cylinders, the difference between groups A and B was statistically significant (p < 0.0001). The differences between groups were also statistically significant for all the evaluated tomographic parameters (p < 0.05). It was concluded that the methodology evaluated can produce standardized bone cylinders of high and low bone density that should be used in future studies to comparatively evaluate the initial stability of dental implants