RESUMO
The aim of this study was to compare implant stability after maxillary sinus floor augmentation using small- or large-sized particles of Bio-Oss. Ten partially edentulous patients requiring bilateral maxillary sinus floor augmentation were enrolled. The subjects were assigned randomly to one of two experimental groups: maxillary sinus was filled with 0.25-1mm particle size (small particles) and the contralateral side was filled with 1-2mm particle size (large particles). After 8 months, a total of 25 implants were placed in the two maxillary sinuses. Primary implant stability was measured immediately after implant placement (T0) using a torque controller and resonance frequency analysis (RFA). Six months after implant placement (T1), the implant stability was measured again. There were no postoperative complications in either particle size group, and the success rate for implant survival was 100%. All implants showed good primary stability as evidenced by high torque for the implant insertion in both groups. RFA revealed high ISQ values for all implants installed in both groups at T0 and T1. These results indicate that the size of the Bio-Oss particles (small and large) did not influence implant stability in the maxillary sinus. Indeed, small and large particles of Bio-Oss presented optimal properties, supporting their possible use as osteoconductive grafts.
Assuntos
Substitutos Ósseos/uso terapêutico , Seio Maxilar/cirurgia , Minerais/uso terapêutico , Levantamento do Assoalho do Seio Maxilar/métodos , Adulto , Idoso , Animais , Transplante Ósseo , Bovinos , Implantação Dentária Endóssea , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Estudos ProspectivosRESUMO
AIM: Clinical data are scarce on flapless-guided surgery in the mandible using the all-on-four concept. In addition, limited documentation exists on the latter under immediate loading conditions with a pre-fabricated implant bridge. The aim was to provide detailed documentation focusing on clinical and radiographic outcome and complications. MATERIAL AND METHODS: Sixteen systemically healthy non-smoking patients (10 women, 6 men, average age 59 years) with sufficient bone volume in the mandible were operated via flapless-guided surgery using the all-on-four concept. Clinical and radiographic data and complications were registered at 3, 6 and 12 months. RESULTS: The overall implant survival rate was 90% with a trend for higher failure of short implants (P = 0.098). The mean bone level after 12 months of function was 0.83 mm with a maximum of 1.07 mm. Technical complications were common (15/16 patients). These mainly related to a misfit between the pre-fabricated prosthesis and abutment(s) (13/16 patients). CONCLUSION: If immediate loading of implants is pursued fabrication of the implant bridge should be based on actual impression of the implants at the time of surgery and not on their virtual position.
Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário/métodos , Mandíbula/cirurgia , Idoso , Dente Suporte , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Radiografia , Resultado do TratamentoRESUMO
OBJECTIVE: The aim of this study was to assess vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in maxillary sinus augmentation with autogenous bone and different graft materials for evaluating their angiogenic potential. METHODS: Biopsies were harvested 10 months after sinus augmentation with a combination of autogenous bone and different graft materials: hydroxyapatite (HA, n = 6 patients), demineralized freeze-dried bone allograft (DFDBA, n = 5 patients), calcium phosphate (CP, n = 5 patients), Ricinus communis polymer (n = 5 patients) and control group--autogenous bone only (n = 13 patients). RESULTS: In all the samples, higher intensities of VEGF expression were prevalent in the newly formed bone, while lower intensities of VEGF expression were predominant in the areas of mature bone. The highest intensity of VEGF expression in the newly formed bone was expressed by HA (P < 0.001) and CP in relation to control (P < 0.01) groups. The lowest intensities of VEGF expression in newly formed bone were shown by DFDBA and polymer groups (P < 0.05). When comparing the different grafting materials, higher MVD were found in the newly formed bone around control, HA and CP (P < 0.001). CONCLUSION: Various graft materials could be successfully used for sinus floor augmentation; however, the interactions between bone formation and angiogenesis remain to be fully characterized.
Assuntos
Processo Alveolar/fisiologia , Substitutos Ósseos/uso terapêutico , Maxila/fisiologia , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Processo Alveolar/irrigação sanguínea , Processo Alveolar/cirurgia , Aumento do Rebordo Alveolar/métodos , Materiais Biocompatíveis/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Transplante Ósseo/métodos , Fosfatos de Cálcio/uso terapêutico , Humanos , Hidroxiapatitas/uso terapêutico , Maxila/irrigação sanguínea , Maxila/cirurgia , Seio Maxilar/irrigação sanguínea , Seio Maxilar/fisiologia , Seio Maxilar/cirurgia , Microvasos/efeitos dos fármacos , Microvasos/crescimento & desenvolvimento , Neovascularização Fisiológica/fisiologia , Osseointegração/fisiologia , Resinas Vegetais/uso terapêutico , RicinusRESUMO
BACKGROUND AND OBJECTIVE: Cyclosporine A is an immunosuppressive drug that is widely used in organ transplant patients as well as to treat a number of autoimmune conditions. Bone loss is reported as a significant side-effect of cyclosporine A use because this can result in serious morbidity of the patients. As we have shown that cyclosporine A-associated bone loss can also affect the alveolar bone, the purpose of this study was to evaluate the effect of the concomitant administration of alendronate on alveolar bone loss in a rat model. MATERIAL AND METHODS: Forty Wistar rats (10 per group) were given cyclosporine A (10 mg/kg, daily), alendronate (0.3 mg/kg, weekly), or both cyclosporine A and alendronate, for 60 d. The control group received daily injections of sterile saline. The expression of proteins associated with bone turnover, including osteocalcin, alkaline phosphatase and tartrate-resistant acid phosphatase (TRAP), and also the calcium levels, were evaluated in the serum. Analysis of the bone volume, alveolar bone surface, the number of osteoblasts per bone surface and the number of osteoclasts per bone surface around the lower first molars was also performed. RESULTS: The results indicate that cyclosporine A treatment was associated with bone resorption, represented by a decrease in the bone volume, alveolar bone surface and the number of osteoblasts per bone surface and by an increase in the number of osteoclasts per bone surface and TRAP-5b. These effects were effectively counteracted by concomitant alendronate administration. CONCLUSION: It is concluded that concomitant administration of alendronate can prevent cyclosporine A-associated alveolar bone loss.
Assuntos
Alendronato/uso terapêutico , Perda do Osso Alveolar/induzido quimicamente , Conservadores da Densidade Óssea/uso terapêutico , Ciclosporina/efeitos adversos , Imunossupressores/efeitos adversos , Fosfatase Ácida/sangue , Alendronato/administração & dosagem , Fosfatase Alcalina/sangue , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Processo Alveolar/efeitos dos fármacos , Processo Alveolar/patologia , Animais , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Cálcio/sangue , Contagem de Células , Modelos Animais de Doenças , Isoenzimas/sangue , Masculino , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteocalcina/sangue , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Fosfatase Ácida Resistente a TartaratoRESUMO
OBJECTIVES: The administration of cyclosporin A has been associated with significant bone loss and increased bone remodeling. The present investigation was designed to evaluate the effects of cyclosporin A on alveolar bone of rats subjected to experimental periodontitis, using serum, stereometric and radiographic analysis. METHODS: Twenty-four rats were divided into one of the following groups with six animals each: group I, control rats; group II, in which the animals received a cotton ligature around the lower first molars; group III, in which the rats received a cotton ligature around the lower first molars and were treated with 10 mg/(kg body weight day) of cyclosporin A; group IV, in which the rats were treated with 10 mg/(kg body weight day) of cyclosporin A. At the end of experimental period, at 30 days, animals were killed and the serum calcium and alkaline phosphatase levels were measured in all groups. The distance from the alveolar bone crest to the cemento-enamel junction was measured radiographically for each mesial surface of the lower first molars of each rat. After histological processing, the stereological parameters: volume densities of multinucleated osteoclasts (V(o)), alveolar bone (V(b)), marrow (V(m)), and relation of eroded surface/bone surface (Es/Bs) were assessed at the mesial region of the alveolar bone. RESULTS: Significant decreases in serum calcium were observed in those groups that received cyclosporin A therapy. No significant changes in serum alkaline phosphatase were observed. The therapy with cyclosporin A combined with the ligature placement decreased the V(b) and increased the V(o), V(m) and Es/Bs at the mesial surface of lower first molars. On the other hand, the radiographic data showed that cyclosporin A therapy diminished the alveolar bone loss at the mesial surface of the lower first molars. CONCLUSIONS: Therefore, within the limits of this study, we suggest that cyclosporin A at immunosuppressive levels can bring about an imbalance in the alveolar bone homeostasis in rats. However, in the presence of inflammatory stimulation, the inhibition of the immune system by cyclosporin A may decrease the initial periodontal breakdown.
Assuntos
Perda do Osso Alveolar/induzido quimicamente , Remodelação Óssea/efeitos dos fármacos , Ciclosporina/administração & dosagem , Imunossupressores/administração & dosagem , Periodontite , Fosfatase Alcalina/sangue , Perda do Osso Alveolar/sangue , Perda do Osso Alveolar/diagnóstico por imagem , Análise de Variância , Animais , Densidade Óssea/efeitos dos fármacos , Cálcio/sangue , Ciclosporina/efeitos adversos , Modelos Animais de Doenças , Imunossupressores/efeitos adversos , Ligadura , Periodontite/tratamento farmacológico , Radiografia , Ratos , Ratos Sprague-Dawley , Estatísticas não ParamétricasRESUMO
BACKGROUND: Major surgical procedures are performed with increasing frequency in elderly persons, but the impact of age on resource use and outcomes is uncertain. OBJECTIVE: To evaluate the influence of age on perioperative cardiac and noncardiac complications and length of stay in patients undergoing noncardiac surgery. DESIGN: Prospective cohort study. SETTING: Urban academic medical center. PATIENTS: Consecutive sample of 4315 patients 50 years of age or older who underwent nonemergent major noncardiac procedures. MEASUREMENTS: Major perioperative complications (cardiac and noncardiac), in-hospital mortality, and length of stay. RESULTS: Major perioperative complications occurred in 4.3% (44 of 1015) of patients 59 years of age or younger, 5.7% (93 of 1646) of patients 60 to 69 years of age, 9.6% (129 of 1341) of patients 70 to 79 years of age, and 12.5% (39 of 313) of patients 80 years of age or older (P < 0.001). In-hospital mortality was significantly higher in patients 80 years of age or older than in those younger than 80 years of age (0.7% vs. 2.6%, respectively). Multivariate analyses indicated an increased odds ratio for perioperative complications or in-hospital mortality in patients 70 to 79 years of age (1.8 [95% CI, 1.2 to 2.7]) and those 80 years of age or older (OR, 2.1 [CI, 1.2 to 3.6]) compared with patients 50 to 59 years of age. Patients 80 years of age or older stayed an average of 1 day more in the hospital, after adjustment for other clinical data (P = 0.001). CONCLUSIONS: Elderly patients had a higher rate of major perioperative complications and mortality after noncardiac surgery and a longer length of stay, but even in patients 80 years of age or older, mortality was low.
Assuntos
Fatores Etários , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Tempo de Internação , Complicações Pós-Operatórias/mortalidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Análise de Regressão , Estatísticas não ParamétricasRESUMO
Titanium alloys are hoped to be used much more for applications as implant materials in the medical and dental fields because of their basic properties, such as biocompatibility, corrosion resistance and specific strength compared with other metallic implant materials. Thus, the Ti-6Al-7Nb alloy that has recently been developed for biomedical use, that is, primarily developed for orthopaedic use, is to be studied in this paper, for application in dental implants. The biocompatibility test in vivo was carried out in dogs and the osseointegration was verified through histological analysis of the samples of the Ti-6Al-7Nb alloy with and without hydroxyapatite coating that were inserted in the alveoli. Within the controlled conditions the samples did not show any toxic effects on the cells.
RESUMO
BACKGROUND: Various procedures have been proposed to treat gingival recession, but few studies compare these procedures to each other. The purpose of this study was to evaluate a clinical comparison of subepithelial connective tissue graft (SCTG) and guided tissue regeneration (GTR) with a collagen membrane in the treatment of gingival recessions in humans. METHODS: Twenty-four defects were treated in 12 patients who presented canine or pre-molar Miller Class I and/or II bilateral gingival recessions. Both treatments were performed in all patients, and clinical measurements were obtained at baseline and 18 months after surgery. These clinical measurements included gingival recession height (GR), root coverage (RC), probing depth (PD), keratinized tissue width (KT), and final esthetic result. RESULTS: Both SCTG and GTR with a bioabsorbable membrane and bone graft demonstrated significant clinical and esthetic improvement for gingival recession coverage. The SCTG group was statistically significantly better than GTR for height of GR (SCTG = 0.2 mm, GTR = 1.12 mm, P= 0.02) and KT (SCTG = 4.58 mm, GTR = 2.5 mm, P<0.0001). However, PD was statistically significantly better for GTR than SCTG treatment (GTR = 1.66 mm, SCTG = 1.00, P= 0.01). The 2 procedures were statistically similar in root coverage (SCTG = 95.6%, GTR = 84.2%, P= 0.073). The esthetic condition after both treatments was satisfactory (P= 0.024). CONCLUSIONS: It was concluded that the gingival recessions treated with the SCTG group were superior for GR, RC, and KT clinical parameters, while GTR demonstrated better PD reduction. The final esthetic results were similar using both techniques.
Assuntos
Gengiva/transplante , Retração Gengival/cirurgia , Regeneração Tecidual Guiada Periodontal , Procedimentos Cirúrgicos Bucais/métodos , Implantes Absorvíveis , Adulto , Colágeno , Tecido Conjuntivo/transplante , Estética Dentária , Feminino , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Masculino , Membranas Artificiais , Pessoa de Meia-Idade , Satisfação do Paciente , Retalhos Cirúrgicos , Resultado do TratamentoRESUMO
BACKGROUND: The poor predictability of periodontal regenerative treatment of Class III furcation defects stimulates the study of alternatives to improve its results, such as the use of polypeptide growth factors. The objective of this study was to evaluate, both histologically and histometrically, the effects of topical application of basic fibroblast growth factor (b-FGF) associated with guided tissue regeneration (GTR) in the treatment of Class III defects surgically induced in dogs. METHODS: All second and fourth premolars of 5 mongrel dogs were used and randomly assigned to one of three treatment groups: group 1 (control), treated with scaling and root planing, tetracycline hydrochloride (125 mg/ml) conditioning, and GTR with a collagen membrane; group 2, same treatment as group 1 plus 0.5 mg of b-FGF; group 3, same treatment as group 1 plus 1.0 mg of b-FGF. After a 90-day healing period, routine histologic processing and staining with hematoxylin and eosin and Masson trichrome were performed. RESULTS: The descriptive analysis indicated better regenerative results in both groups treated with b-FGF while the histometric data, analyzed by means of analysis of variance (ANOVA), showed greater filling of the defects in group 2 in comparison to the defects in groups 3 and 1, respectively, which was represented by a smaller area of plaque-occupied space (P = 0.004) as well as a greater amount of newly formed cementum (P = 0.002). CONCLUSIONS: These results indicate that b-FGF, especially in smaller doses, may enhance the regenerative results in Class III furcation lesions, leading to greater filling of these defects with both mineralized and non-mineralized tissues.
Assuntos
Regeneração Óssea/efeitos dos fármacos , Cemento Dentário/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Defeitos da Furca/tratamento farmacológico , Regeneração Tecidual Guiada Periodontal/métodos , Análise de Variância , Animais , Cães , Fator 2 de Crescimento de Fibroblastos/farmacologia , Defeitos da Furca/cirurgia , Análise Multivariada , Distribuição Aleatória , Estatísticas não ParamétricasRESUMO
The present study compares the biologic behavior of BioGran and Calcitite as fillers for surgical cavities in the mandibles of 4 adult monkeys (Cebus apella). The surgical cavities were prepared through both mandibular cortices, with a diameter of 5 mm, in the angle region. Two cavities were prepared on the right side and 1 on the left and divided into 3 groups: R1 sites were filled with bioglass (BioGran), R2 sites were not filled, and L sites were filled with hydroxyapatite (Calcitite). After 180 days the animals were sacrificed and the specimens were removed for histologic processing. Results showed no bone formation in group R2 (empty cavities). BioGran-treated sites showed bone formation and total repair of the bone defect, and the bioglass particles were almost totally resorbed and substituted by bone. The few remaining crystals were in intimate contact with newly formed bone. Calcitite did not allow bone formation, and granules inside the cavities were involved by connective tissue. Based upon those results, the authors concluded that bioglass resulted in total obliteration of the surgical cavity with bone and hydroxyapatite was present in a large amount and involved by connective tissue, without bone formation.