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1.
J Oral Implantol ; 49(1): 85-92, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35446964

RESUMO

This systematic review addressed the implant success rate after mandible reconstruction with vascularized fibula bone graft. Therefore, preferred reporting items for systematic review and meta-analysis guidelines were used to perform the systematic review, and the search included following databases: PubMed, Lilacs, Google Scholar, Open Gray, Science Direct and Cochrane. A search of medical subject headings (MeSH) and related terms (fibula) OR (vascularized) OR (microvascularized) AND (implant) OR (rehabilitation) OR (osseointegrated) AND (mandible) OR (jaw) OR (maxillofacial), without any language or time restrictions until October 2017 was carried out. The eligible studies primarily consisted of clinical cohorts designed to evaluate the feasibility of mandible reconstruction using vascularized fibula bone grafts and implant-supported rehabilitations, with a minimum observation period of 12 months. After screening, 13 eligible cohort studies for this review were selected (3 retrospective and 10 prospective). Of 285 vascularized fibular reconstructions, only 6 failures were reported with a success rate of approximately 98% after a mean follow-up period of 40 months. In total, 910 implants were placed in vascularized fibular grafts with a success rate of 92.6% (range, 82%-100%) after 40 months. Also, similar success rates for primary (95%; range, 93%-100%) and secondary (91%; range, 83%-100%) implant surgeries have been demonstrated. Considering risk factors, implant survival in irradiated patients was usually lower (76%; range, 38%-88%) than nonirradiated patients (90%; range, 83%-94%); however, it was significantly different in only 1 study. Alcohol and tobacco use has shown no significant association with implant failure in any study. Hence, implant placement in vascularized fibula bone graft presented similar success rates relative to native mandible bone rehabilitations.


Assuntos
Implantes Dentários , Humanos , Retalhos Cirúrgicos , Estudos Retrospectivos , Estudos Prospectivos , Fíbula/transplante , Mandíbula/cirurgia , Transplante Ósseo
2.
J Dent ; 100: 103436, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32738285

RESUMO

OBJECTIVES: To evaluate the clinical outcomes, histological parameters, and bone nanomechanical properties around implants retrieved from healthy and metabolic syndrome (MS) patients. METHODS: Twenty-four patients with edentulous mandibles (12/condition), received four implants between the mental foramina. An additional implant prototype was placed for retrieval histology. The following clinical outcomes were evaluated: insertion torque (IT), implant stability quotient (ISQ) values at baseline and after 60 days of healing, and implant survival. The prototype was retrieved after the healing and histologically processed for bone morphometric evaluation of bone-to-implant contact (%BIC) and bone area fraction occupancy (%BAFO), and bone nanoindentation to determine the elastic modulus (Em) and hardness (H). Descriptive statistical procedures and survival tests were used to analyze the data. RESULTS: The final study population was comprised of 10 women and 11 men (∼64 years). A total of 105 implants were placed, 21 retrieved for histology. Implant survival rates were similar between groups (>99 %). Similarly, IT and ISQ analyses showed no significant association with systemic condition (p > 0.216). Histological micrographs depicted similar bone morphology, woven bone, for both conditions. While MS (33 ±â€¯5.3 %) and healthy (39 ±â€¯6.5 %) individuals showed no significant difference for %BIC (p = 0.116), significantly higher %BAFO was observed for healthy (45 ±â€¯4.6 %) relative to MS (30 ±â€¯3.8 %) (p < 0.001). No significant differences on bone nanomechanical properties was observed (p > 0.804). CONCLUSIONS: Although no significant influence on clinical parameters and bone nanomechanical properties was observed, MS significantly reduced bone formation in the peri-implant area in the short-term. CLINICAL SIGNIFICANCE: A lower amount of bone formation in the peri-implant area was observed in comparison to healthy patients, although the other short-term clinical outcomes were not significantly different. Considering the escalating prevalence of MS patients in need for implant treatment, it becomes crucial to understand bone-to-implant response to determine the ideal loading time in this population.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Feminino , Humanos , Masculino , Osseointegração
3.
J Craniofac Surg ; 30(6): 1873-1874, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31756876

RESUMO

Bone graft augmentation in the anterior maxilla has a high successful rate. However, suture dehiscence and consequent bone graft exposure can compromise and fail this procedure. Therefore, this article presents a new strategy of closure technique to guarantee the bone graft augmentation. The sutures occur in muscular and mucous planes to avoid suture tension, thus decreasing complications of bone graft augmentation in the anterior maxilla.


Assuntos
Transplante Ósseo/métodos , Maxila/cirurgia , Implantação Dentária Endóssea , Implantes Dentários , Humanos
4.
J Mech Behav Biomed Mater ; 97: 288-295, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31146202

RESUMO

This study evaluated the effect of alumina-blasted/acid-etched (AB/AE) or microabrasive blasting (C3-Microblasted) surface treatment on the osseointegration of commercially-pure Ti (grade II) and Ti-6Al-4V alloy (grade V) implants compared to as-machined surfaces. Surface characterization was performed by scanning electron microscopy and optical interferometry (IFM) to determine roughness parameters (Sa and Sq, n = 3 per group). One-hundred forty-four implants were placed in the radii of 12 beagle dogs, for histological (n = 72, bone-to-implant contact - BIC and bone-area-fraction occupancy -BAFO) and torque to interface failure test at 3 and 6 weeks (n = 72). SEM and IFM revealed a significant increase in surface texture for AB/AE and C3-Microblasted surfaces compared to machined surface, regardless of titanium substrate. Torque-to-interface failure test showed significant increase in values from as-machined to AB/AE and to C3-Microblasted. Considering time in vivo, alloy grade, and surface treatment, the C3-microblasted presented higher mean BIC values relative to AB/AE and machined surfaces for both alloy types. BAFO levels were significantly higher for both textured surfaces groups relative to the machined group at 3 weeks, but differences were not significant between the three surfaces for each alloy type at 6 weeks. Surface treatment resulted in roughness that improved osseointegration in Grade II and V titanium substrates.


Assuntos
Condicionamento Ácido do Dente/métodos , Óxido de Alumínio/química , Implantes Dentários , Osseointegração , Titânio/química , Ligas , Animais , Cães , Interferometria , Masculino , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Resistência à Tração , Torque
5.
Implant Dent ; 25(5): 650-5, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27540838

RESUMO

PURPOSE: To evaluate the bone response to grade IV commercially pure titanium (G4) relative to Ti-6Al-4V (G5). MATERIALS AND METHODS: Implant surface topography was characterized by optical interferometry and scanning electron microscopy (SEM). Thirty-six implants (Signo Vinces, n = 18 per group) were installed in the radius of 18 dogs. The animals were killed at 1, 3, and 6 weeks, resulting in 6 implants per group and time in vivo for bone morphology, bone-to-implant contact (BIC), and bone area fraction occupancy (BAFO) evaluation. RESULTS: SEM depicted a more uniform topography of G4 than G5. Surfaces were statistically homogeneous for Sa, Sq, and Sdr. At 1 week, new bone formation was observed within the healing connective tissue in contact with the implant surface. At 3 weeks, new bone in direct contact with the implant surface was observed at all bone regions. At 6 weeks, the healing chambers filled with woven bone depicted an onset of replacement by lamellar bone. No significant effect of substrate was detected. Time presented an effect on BIC and BAFO (P < 0.001). CONCLUSION: Both titanium substrates were biocompatible and osseoconductive at the bone tissue level.


Assuntos
Interface Osso-Implante/patologia , Implantes Dentários , Titânio , Ligas , Animais , Implantação Dentária Endóssea , Implantes Dentários/efeitos adversos , Cães , Masculino , Microscopia Eletrônica de Varredura
6.
Implant Dent ; 25(6): 739-743, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27513163

RESUMO

PURPOSE: This study investigated the effect of the osteotomy diameter for implant placement torque and its effect on the osseointegration. MATERIALS AND METHODS: Eight male beagle dogs received 48 implants (3.75 mm × 10 mm) in their right and left radius, 3 implants per side and allowed to heal for 3 weeks. Three experimental groups were evaluated. Group 1: implant with an undersized osteotomy of 3.0 mm; group 2: osteotomy of 3.25 mm, and group 3: osteotomy of 3.5 mm. The insertion torque was recorded for all implants. Histological sectioning and histometric analysis were performed evaluating bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). RESULTS: Implants of group 1 presented statistically higher insertion torque than those of groups 2 and 3 (P < 0.01). No differences in BIC or BAFO were observed between the groups. From a morphologic standpoint, substantial deviations in healing mode were observed between groups. CONCLUSION: Based on the present methodology, the experimental alterations of surgical technic can be clinically used with no detrimental effect over the osseointegration process.


Assuntos
Implantação Dentária Endóssea/métodos , Osseointegração , Osteotomia/métodos , Cicatrização , Animais , Cães , Masculino , Rádio (Anatomia)/transplante , Torque
7.
J Oral Maxillofac Surg ; 74(3): 505-14, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26433041

RESUMO

PURPOSE: Recombinant human bone morphogenetic protein type 2 (rhBMP-2) has been used to promote bone regeneration. In contrast, some reports have suggested rhBMP-2 does not provide advantages over autogenous bone grafting owing to the undesirable postoperative symptoms of this growth factor. Because the undesirable symptoms of rhBMP-2 are usually promoted by inflammation, this study evaluated the in vivo effect of human adipose-derived stem cells (ASCs) incorporated into polylactic co-glycolic acid (PLGA) scaffolds in decreasing the inflammatory response induced by a low dose of rhBMP-2. MATERIALS AND METHODS: PLGA scaffolds were characterized and loaded with rhBMP-2 1, 2.5, or 5 µg per scaffold (n = 6) and the in vitro released protein amounts were quantified at 7 hours and 1, 7, and 21 days after loading (n = 3). The muscle tissue of 6 beagles received the following treatments: PLGA, PLGA plus rhBMP-2 (2.5 µg), and PLGA plus rhBMP-2 plus ASCs (1 × 10(6) ASCs). The samples were evaluated 45 days after surgery. Statistical analyses were performed and the P value was set at .05. RESULTS: PLGA plus rhBMP-2 plus ASCs yielded the smallest number of inflammatory foci (P < .001) and giant cells (P < .001) and the largest number of angiogenesis sites (P < .001). CONCLUSIONS: Human ASCs administered in vivo into PLGA scaffolds with a low dose of rhBMP-2 decrease tissue inflammation and increase angiogenesis in muscular sites.


Assuntos
Tecido Adiposo/citologia , Proteína Morfogenética Óssea 2/uso terapêutico , Células-Tronco Mesenquimais/fisiologia , Fator de Crescimento Transformador beta/uso terapêutico , Implantes Absorvíveis , Animais , Materiais Biocompatíveis/química , Proteína Morfogenética Óssea 2/imunologia , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Cães , Células Gigantes/efeitos dos fármacos , Células Gigantes/patologia , Humanos , Inflamação , Ácido Láctico/química , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/cirurgia , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/fisiologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , Fatores de Tempo , Alicerces Teciduais/química , Fator de Crescimento Transformador beta/imunologia , Adulto Jovem
8.
J Biomed Mater Res B Appl Biomater ; 104(6): 1091-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26034012

RESUMO

Healing chambers present at the interface between implant and bone have become a target for improving osseointegration. The objective of the present study was to compare osseointegration of several implant healing chamber configurations at early time points and regions of interest within bone using an in vivo animal femur model. Six implants, each with a different healing chamber configuration, were surgically implanted into each femur of six skeletally mature beagle dogs (n = 12 implants per dog, total n = 72). The implants were harvested at 3 and 5 weeks post-implantation, non-decalcified processed to slides, and underwent histomorphometry with measurement of bone-to-implant contact (BIC) and bone area fraction occupied (BAFO) within healing chambers at both cortical and trabecular bone sites. Microscopy demonstrated predominantly woven bone at 3 weeks and initial replacement of woven bone by lamellar bone by 5 weeks. BIC and BAFO were both significantly increased by 5 weeks (p < 0.001), and significantly higher in cortical than trabecular bone (p < 0.001). The trapezoidal healing chamber design demonstrated a higher BIC than other configurations. Overall, a strong temporal and region-specific dependence of implant osseointegration in femurs was noted. Moreover, the findings suggest that a trapezoidal healing chamber configuration may facilitate the best osseointegration. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1091-1097, 2016.


Assuntos
Interface Osso-Implante , Fêmur/metabolismo , Implantes Experimentais , Osseointegração , Desenho de Prótese , Animais , Cães , Fêmur/patologia
9.
Adv Exp Med Biol ; 881: 111-28, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26545747

RESUMO

Endosteal dental implants have been utilized as anchors for dental and orthopedic rehabilitations for decades with one of the highest treatment success rates in medicine. Such success is due to the phenomenon of osseointegration where after the implant surgical placement, bone healing results into an intimate contact between bone and implant surface. While osseointegration is an established phenomenon, the route which osseointegration occurs around endosteal implants is related to various implant design factors including surgical instrumentation and implant macro, micro, and nanometer scale geometry. In an implant system where void spaces (healing chambers) are present between the implant and bone immediately after placement, its inherent bone healing pathway results in unique opportunities to accelerate the osseointegration phenomenon at the short-term and its maintenance on the long-term through a haversian-like bone morphology and mechanical properties.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Osseointegração/fisiologia , Cicatrização/fisiologia , Animais , Remodelação Óssea/fisiologia , Materiais Revestidos Biocompatíveis/química , Materiais Dentários/química , Planejamento de Prótese Dentária , Módulo de Elasticidade/fisiologia , Humanos , Osteogênese/fisiologia , Propriedades de Superfície , Fatores de Tempo
10.
Biomed Res Int ; 2015: 761718, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26090443

RESUMO

This study assessed the osseointegrative effects of atmospheric pressure plasma (APP) surface treatment for implants in a canine model. Control surfaces were untreated textured titanium (Ti) and calcium phosphate (CaP). Experimental surfaces were their 80-second air-based APP-treated counterparts. Physicochemical characterization was performed to assess topography, surface energy, and chemical composition. One implant from each control and experimental group (four in total) was placed in one radius of each of the seven male beagles for three weeks, and one implant from each group was placed in the contralateral radius for six weeks. After sacrifice, bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were assessed. X-ray photoelectron spectroscopy showed decreased surface levels of carbon and increased Ti and oxygen, and calcium and oxygen, posttreatment for Ti and CaP surfaces, respectively. There was a significant (P < 0.001) increase in BIC for APP-treated textured Ti surfaces at six weeks but not at three weeks or for CaP surfaces. There were no significant (P = 0.57) differences for BAFO between treated and untreated surfaces for either material at either time point. This suggests that air-based APP surface treatment may improve osseointegration of textured Ti surfaces but not CaP surfaces. Studies optimizing APP parameters and applications are warranted.


Assuntos
Pressão Atmosférica , Implantes Dentários , Osseointegração/fisiologia , Animais , Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Cães , Humanos , Masculino , Propriedades de Superfície , Titânio/química
11.
Dent Traumatol ; 31(1): 42-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25336206

RESUMO

BACKGROUND/AIM: Some cases of tooth loss related to dental trauma require bone-grafting procedures to improve the aesthetics before prosthetic rehabilitation or to enable the installation of dental implants. Bone regeneration is often a challenge and could be largely improved by mesenchymal stem cells therapy. However, the appropriate scaffold for these cells still a problem. This study evaluated the in vivo effect of human adipose-derived stem cells incorporated into autogenous platelet-rich plasma in bone regeneration and maturation. MATERIAL AND METHODS: Adipose-derived stem cells were isolated from lipoaspirate tissues and used at passage 4. Immunophenotyping and multilineage differentiation of cells were performed and mesenchymal stem cells characteristics confirmed. Bicortical bone defects (10 mm diameter) were created in the tibia of six beagle dogs to evaluate the effect of adipose-derived stem cells incorporated into platelet-rich plasma scaffolds, platelet-rich plasma alone, autogenous bone grafts, and clot. Samples were removed 6 weeks postsurgeries and analyzed by quantification of primary and secondary bone formation and granulation tissue. RESULTS: Adipose-derived stem cells incorporated into platelet-rich plasma scaffolds promoted the highest bone formation (primary + secondary bone) (P < 0.001), the highest bone maturation (secondary bone) (P < 0.001), and the lowest amount of granulation tissue (P < 0.001). CONCLUSIONS: Adipose-derived stem cells incorporated into platelet-rich plasma scaffolds promote more bone formation and maturation, and less granulation tissue in bone defects created in canine tibia. Therefore, platelet-rich plasma can be considered as a candidate scaffold for adipose-derived stem cells to promote bone regeneration.


Assuntos
Tecido Adiposo/citologia , Regeneração Óssea/fisiologia , Transplante Ósseo/métodos , Células-Tronco Mesenquimais/fisiologia , Plasma Rico em Plaquetas , Tíbia/cirurgia , Animais , Diferenciação Celular , Sobrevivência Celular , Cães , Humanos , Imunofenotipagem
12.
J Biomed Mater Res B Appl Biomater ; 103(6): 1328-32, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25367155

RESUMO

Although preclinical and sparse human histology retrieval studies have shown that the interface between implant and bone is constantly remodeling, no human retrieval database has been developed to determine the effect of functional loading time and other clinical/implant design variables on osseointegration. The present study tested the hypothesis that bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) increase over functional loading time around dental implants. Due to prosthetic retreatment reasons, 93 human implant retrievals from the same manufacturer (Bicon LLC, Boston, MA, USA) were obtained over a period of approximately 15 years. The retrieved implants were under functional loading from 120 days to ∼18 years and were histomorphologic/metrically evaluated. BIC/BAFO were assessed as a function of multiple independent variables: implant surface type, diameter, length, jaw (maxilla/mandible), region (anterior/posterior), and time of functional loading. The results showed that both BIC and BAFO increased over time independently of implant design/clinical variables, supporting the postulated hypothesis.


Assuntos
Interface Osso-Implante/patologia , Implantação Dentária Endóssea , Implantes Dentários , Feminino , Humanos , Masculino , Fatores de Tempo , Suporte de Carga
13.
Mater Sci Eng C Mater Biol Appl ; 45: 484-90, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25491854

RESUMO

Bone graft materials are utilized to stimulate healing of bone defects or enhance osseointegration of implants. In order to augment these capabilities, various surface modification techniques, including atmospheric pressure plasma (APP) surface treatment, have been developed. This in vivo study sought to assess the effect of APP surface treatment on degradation and osseointegration of Synthograft™, a beta-tricalcium phosphate (ß-TCP) synthetic bone graft. The experimental (APP-treated) grafts were subjected to APP treatment with argon for a period of 60s. Physicochemical characterization was performed by environmental scanning electron microscopy, surface energy (SE), and x-ray photoelectron spectroscopy analyses both before and after APP treatment. Two APP-treated and two untreated grafts were surgically implanted into four critical-size calvarial defects in each of ten New Zealand white rabbits. The defect samples were explanted after four weeks, underwent histological analysis, and the percentages of bone, soft tissue, and remaining graft material were quantified by image thresholding. Material characterization showed no differences in particle surface morphology and that the APP-treated group presented significantly higher SE along with higher amounts of the base material chemical elements on it surface. Review of defect composition showed that APP treatment did not increase bone formation or reduce the amount of soft tissue filling the defect when compared to untreated material. Histologic cross-sections demonstrated osteoblastic cell lines, osteoid deposition, and neovascularization in both groups. Ultimately, argon-based APP treatment did not enhance the osseointegration or degradation of the ß-TCP graft. Future investigations should evaluate the utility of gases other than argon to enhance osseointegration through APP treatment.


Assuntos
Argônio/química , Materiais Biocompatíveis/química , Substitutos Ósseos/química , Animais , Pressão Atmosférica , Materiais Biocompatíveis/farmacologia , Substitutos Ósseos/farmacologia , Osso e Ossos/patologia , Fosfatos de Cálcio/química , Linhagem Celular , Masculino , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteogênese/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Próteses e Implantes , Coelhos , Propriedades de Superfície
14.
J Oral Maxillofac Surg ; 72(2): 305.e1-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24438601

RESUMO

PURPOSE: The objective of this study was to evaluate the influence of 4 different amoxicillin administration protocols on osseointegration of dental implants. MATERIALS AND METHODS: Thirty-five Wistar rats received an implant in the right tibia and were divided into 5 groups (n = 7): the control group (G1), a group that received a single dose of amoxicillin suspension (40 mg/kg) hour before surgery (G2), a group that received amoxicillin suspension 1 hour before surgery and a 10-mg/kg dose every 12 hours for 3 days (G3), a group that received amoxicillin suspension 1 hour before surgery and a 10-mg/kg dose every 12 hours for 5 days (G4), and a group that received amoxicillin suspension 1 hour before surgery and a 10-mg/kg dose every 12 hours for 7 days (G5). The animals were sacrificed by anesthesia overdose 28 days after implant placement. The samples were retrieved for bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) analyses. RESULTS: BIC analysis indicated 3 different statistical groups: G1 plus G2, G3, and G4 plus G5. There was no statistical difference between G1 and G2 or between G4 and G5. G3 presented lower values, with statistical difference for G1 plus G2 and G4 plus G5. Also, a statistical difference was found between G1 plus G2 and G4 plus G5. For BAFO evaluation, no statistical difference was found for the experimental groups. CONCLUSION: The results of this study suggest that prolonged use of amoxicillin might have a negative effect on bone formation around implants.


Assuntos
Amoxicilina/efeitos adversos , Antibacterianos/efeitos adversos , Osseointegração/efeitos dos fármacos , Amoxicilina/administração & dosagem , Animais , Antibacterianos/administração & dosagem , Implantes Dentários , Relação Dose-Resposta a Droga , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Tíbia
15.
ImplantNews ; 11(3): 296-301, 2014. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-730877

RESUMO

Objetivo: apresentar os resultados histológicos e histomorfométricos do uso de três substitutos ósseos disponíveis comercialmente, com relação à sua capacidade de regeneração óssea. Material e métodos: foram utilizados três biomateriais para preenchimento de defeitos críticos na calvária de coelhos, e mantidos por quatro e oito semanas in vivo. Resultados: do ponto de vista morfológico, um padrão de cicatrização semelhante foi observado para os três diferentes materiais, em que a formação do osso foi observada a partir das margens para o centro do defeito, nos tempos decorridos in vivo. De um ponto de vista quantitativo, o material NanoSynt apresentou maiores níveis médio de formação óssea, quantidade de biomaterial e de manutenção de espaço do defeito in vivo, quando comparado aos outros dois biomateriais. Conclusão: todos os substitutos ósseos utilizados apresentaram características de biocompatibilidade, não interferindo negativamente no processo de reparo. Entretanto, o biomaterial sintético NanoSynt apresentou maior nível de formação óssea e manutenção do espaço do defeito, quando comparado aos materiais Boneceramic e Bio-Oss durante os dois períodos in vivo do presente estudo (quatro e oito semanas).


Objective: to present the histological and histomorphometric results on the use of three commercially available bone substitutes with respect to its capacity of bone regeneration. Material and methods: three biomaterials were used to fill critical defects in the calvaria of rabbits kept 4 and 8 weeks in vivo. Results: from the morphological point of view, a similar pattern of healing was observed for three different materials, in which bone formation was observed from the margins to the center of the deffect, according to evaluated periods. From a quantitative point of view, the NanoSynt material exhibited higher mean levels of bone formation, amount of biomaterial, and space maintenance defect in vivo when compared to the other two biomaterials. Conclusion: all bone substitutes used showed biocompatibility and does not interfere negatively in the repair process. However, the synthetic biomaterial NanoSynt showed higher levels of bone formation and maintenance of the area of the defect when compared to materials BoneCeramic and Bio-Oss during the two periods in vivo in the present study (4 and 8 weeks).


Assuntos
Animais , Coelhos , Materiais Biocompatíveis , Regeneração Óssea
16.
Int J Dent ; 2013: 296391, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24285956

RESUMO

Lateral or vertical bone augmentation has always been a challenge, since the site is exposed to constant pressure from the soft tissue, and blood supply only exists from the donor site. Although, for such clinical cases, onlay grafting with autogenous bone is commonly selected, the invasiveness of the secondary surgical site and the relatively fast resorption rate have been reported as a drawback, which motivated the investigation of alternative approaches. This study evaluated the bone-forming capability of a novel nanoHA alloplast infused with collagen graft material made from biodegradable polylactic acid/polyglycolic acid versus a control graft material with the same synthesized alloplast without the nanoHA component and collagen infiltration. The status of newly formed bone and the resorption of the graft material were evaluated at 6 weeks in vivo histologically and three dimensionally by means of 3D microcomputed tomography. The histologic observation showed that newly formed bone ingrowth and internal resorption of the block were observed for the experimental blocks, whereas for the control blocks less bone ingrowth occurred along with lower resorption rate of the block material. The three-dimensional observation indicated that the experimental block maintained the external geometry, but at the same time successfully altered the graft material into bone. It is suggested that the combination of numerous factors contributed to the bone ingrowth and the novel development could be an alternative bone grafting choice.

17.
Implant Dent ; 22(6): 596-603, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24113553

RESUMO

PURPOSE: Commercial implants differ at macro-, micro-, and nanolevels, which makes it difficult to distinguish their effect on osseointegration. The aim of this study was to evaluate the early integration of 5 commercially available implants (Astra OsseoSpeed, Straumann SLA, Intra-Lock Blossom Ossean, Nobel Active, and OsseoFix) by histomorphometry and nanoindentation. MATERIALS AND METHODS: Implants were installed in the tibiae of 18 beagle dogs. Samples were retrieved at 1, 3, and 6 weeks (n = 6 for each time point) and were histologically and nanomechanically evaluated. RESULTS: The results presented that both time (P < 0.01) and implant system and time interaction (P < 0.02) significantly affected the bone-to-implant contact (BIC). At 1 week, the different groups presented statistically different outcomes. No significant changes in BIC were noted thereafter. There were no significant differences in rank elastic modulus (E) or in rank hardness (H) for time (E: P > 0.80; H: P > 0.75) or implant system (E: P > 0.90; H: P > 0.85). CONCLUSIONS: The effect of different implant designs on osseointegration was evident especially at early stages of bone healing.


Assuntos
Implantação Dentária Endóssea/métodos , Osseointegração , Animais , Fenômenos Biomecânicos , Implantes Dentários , Análise do Estresse Dentário , Cães , Tíbia/cirurgia , Cicatrização
18.
J Oral Implantol ; 39(4): 445-53, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23964778

RESUMO

This study evaluated 3 implant surfaces in a dog model: (1) resorbable-blasting media + acid-etched (RBMa), alumina-blasting + acid-etching (AB/AE), and AB/AE + RBMa (hybrid). All of the surfaces were minimally rough, and Ca and P were present for the RBMa and hybrid surfaces. Following 2 weeks in vivo, no significant differences were observed for torque, bone-to-implant contact, and bone-area fraction occupied measurements. Newly formed woven bone was observed in proximity with all surfaces.


Assuntos
Abrasão Dental por Ar/métodos , Implantes Dentários , Osseointegração , Implantes Absorvíveis , Condicionamento Ácido do Dente , Óxido de Alumínio , Animais , Implantação Dentária Endóssea , Cães , Durapatita , Masculino , Propriedades de Superfície , Tíbia/cirurgia , Torque
19.
Int J Oral Maxillofac Implants ; 28(3): 694-700, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23748299

RESUMO

PURPOSE: The present study was conducted to determine whether biomechanical and histologic parameters would differ between implant surfaces blasted with bioactive ceramic resorbable media (biologic blasting) and blasted with alumina and acid-etched. MATERIALS AND METHODS: Fourteen beagle dogs were used. Eight animals received two implants of each surface per limb, and each limb provided samples that remained in vivo for 3 and 6 weeks. The other six animals received two implants of each surface in one limb, which remained in vivo for 1 week. After euthanization, half of the implants were subjected to torque-to-interface fracture; the other half of the implants were processed for nondecalcified histology to calculate bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). Statistical analysis was performed with the Kruskal-Wallis test (95% level of significance). RESULTS: While no significant differences were observed for BIC and BAFO between surfaces at all three times in vivo and for torque levels at 1 and 3 weeks, a significantly higher torque was observed for the biologic blasting group after 6 weeks in vivo. Bone morphology was similar between groups at all times. CONCLUSION: A significant increase in early biomechanical fixation was observed for implants with the biologic blasting surface. However, no significant differences were observed for BIC and BAFO at any observation point.


Assuntos
Implantes Absorvíveis , Óxido de Alumínio , Implantes Dentários , Titânio , Ligas , Animais , Fenômenos Biomecânicos , Parafusos Ósseos , Cerâmica , Corrosão Dentária/métodos , Falha de Restauração Dentária , Cães , Interferometria/métodos , Masculino , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Torque
20.
Int J Oral Maxillofac Implants ; 28(1): 136-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23377058

RESUMO

PURPOSE: Modifications in implant surface topography and chemistry may alter the early bone response at different levels. This study characterized four implant surfaces and evaluated the biomechanical fixation and histologic response at early implantation times in a canine radius model. MATERIALS AND METHODS: External-hexagon Branemark-type implants were used with four experimental surfaces: microblasted (MI), acid-etched and microblasted (AAM), anodized (A), and discrete crystalline deposition (DCD). Surface topography was assessed by scanning electron microscopy, interferometry, and x-ray photoelectron spectroscopy. The implants were placed in the central region of the radii of eight beagle dogs and remained in vivo for 10 or 30 days. The implants were torqued to interface failure, and a general linear statistical model with torque as the dependent variable and implant surface and time in vivo as independent variables was used. RESULTS: All surfaces presented were textured, and different surface chemistries were observed. No significant differences between implant surfaces were observed for torque at 10 days. However, at 30 days, the AAM surface presented significantly higher torque values compared to the DCD and A surfaces. Significantly higher torque values were observed at 30 days compared to 10 days (P < .001). CONCLUSIONS: Significantly different biomechanical fixation dependent on surface preparation was observed after 30 days, and all surfaces were biocompatible and osteoconductive.


Assuntos
Implantes Dentários , Osseointegração , Rádio (Anatomia) , Torque , Animais , Falha de Restauração Dentária , Remoção de Dispositivo , Cães , Interferometria , Masculino , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Fatores de Tempo
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