O elevado número de cirurgias de enxertia óssea impulsiona o desenvolvimento de novos biomateriais de preenchimento. Materiais a base de hidroxiapatita sintética e tendão bovino mineralizado foram preparados para servirem de arcabouço para regeneração óssea. Este estudo teve como objetivo avaliar a osteocondutibilidade desses materiais, comparando-os ao Bio-Oss/Geistlich. Foram criados defeitos de tamanho crítico (circular / 8 mm) na calvária de ratos Wistar, preenchidos com os biomateriais e, após 30 dias, ocorreu o sacrifício, análise não invasiva por microtomografia computadorizada (micro-CT/ microtomógrafo SkyScan 100kV - 100\'mü\'A) com reconstituição de imagem em três dimensões (3D) e análise histológica convencional para avaliar a neoformação óssea e comparar os métodos. Os resultados da micro-CT mostraram que o Bio-Oss apresentou maior volume, densidade e porcentagem de tecido ósseo que os demais grupos. Nas imagens reconstituídas em 3D notou-se no grupo Bio-Oss as menores taxas de reabsorção, permanecendo em maior quantidade no interior do defeito aos trinta dias. No grupo da hidroxiapatita sintética notou-se uma intensa reabsorção do material e uma leve neoformação óssea nas margens do defeito, deixando-o com um contorno irregular. O grupo do tendão bovino mineralizado apresentou discretíssima neoformação óssea e o material foi totalmente reabsorvido. Já na avaliação da presença do material, de vasos sanguíneos e das células osteoblásticas no interior do defeito obtidos através da análise histológica, os grupos Bio-Oss e hidroxiapatita sintética obtiveram resultados semelhantes e maiores que o tendão bovino mineralizado. Constatou-se através da análise histológica que a hidroxiapatita sintética mostrou-se presente no interior do defeito exibindo propriedades osteocondutoras semelhantes a marca comercial Bio-Oss. Já o tendão bovino mineralizado não teve boa osteocondução, sendo contra-indicado na manutenção do espaço ósseo. Na comparação dos dois métodos, constatou-se que a micro-CT apresenta baixa especificidade, ou seja, não foi capaz de distinguir o tecido ósseo do Bio-Oss e alta sensibilidade, pois quantifica de uma forma muito precisa os valores com alta resolução. Já a análise histológica consegue distinguir com precisão os materiais e o tecido adjacente, porém não consegue quantificá-los de maneira fácil e precisa. Portanto, conclui-se que a hidroxiapatita sintética tem grande potencial de ser utilizada no preenchimento de defeitos ósseos, diferentemente do tendão bovino mineralizado. Quanto aos métodos de avaliação, eles são complementares e novos aprimoramentos devem ser feitos na técnica de micro-CT para melhorar sua capacidade de distinguir diferentes materiais. / Biodegradable bone grafts have been widely employed on bone regeneration. The purpose of this study was to evaluate the osteoconductive potential of hydroxyapatite, mineralized bovine tendon and Bio-Oss/Geistlich in a rat critical-size calvaria defect model through non-destructive three-dimensional (3D) micro-tomographic (\'mü\'CT) imaging and histological evaluation. Two experimental biomaterials were developed: synthetic hydroxyapatite (particles size < 0,2 mm) and mineralized bovine tendon. Bio-Oss/Geistlich was employed as a control group. A critical size defect (8 mm) was created in the skull of Wistar rats (weight 200 - 300 g) and treated with the biomaterials and one group was left untreated in the control group (n = 5). After 30 days, the animals were killed and the calvaria removed for \'mü\'CT and histological analysis. No adverse reactions were noted. No bone repair was observed in untreated surgical defects. The results of micro-CT showed that BioOss showed higher volume, density and percentage of bone tissue than the other groups. In the images reconstructed in 3-D was noted in the group Bio-Oss the lowest rates of resorption, staying in larger quantities within thirty days of the defect. In the group of synthetic hydroxyapatite noticed an intense resorption of the material and a slight bone formation at the margins of the defect, leaving him with an irregular contour. The bovine tendon mineralized group presented discreet bone formation and the material was completely resorbed. In the evaluation of the presence of the material, blood vessels and osteoblastic cells within the defect obtained by histological analysis, the groups Bio-Oss and synthetic hydroxyapatite showed similar results and larger than the mineralized bovine tendon. We verified by histological analysis that the synthetic hydroxyapatite is present within the defect displaying osteoconductive properties similar to trademark BioOss. Already the mineralized bovine tendon, again, did not have good osteoconduction and is contraindicated in maintaining the bone. When comparing the two methods observed that the micro-CT has low specificity, ie, was not able to distinguish the bone tissue to Bio-Oss and high sensitivity, as quantified in a very accurate values with high resolution. Already histological analysis can accurately distinguish materials and tissues, but can not quantify them easily and accurately. Therefore, we conclude that the synthetic hydroxyapatite has great potential to be used to fill bone defects, unlike mineralized bovine tendon. When comparing the methods, we found that still are complementary and new enhancements must be made in micro-CT technique to improve their ability to distinguish different materials.

The preclinical imaging method micro-CT (microtomography) allows the visualization and quantification of the structure of samples at a resolution of micrometers. Its' importance is increasing globally. In addition to several advantages (non-destructive, the possibility of direct 3D analysis, time efficiency, etc.), micro-CT also has some significant limitations (problematic validation of results, image artifacts, significant influence of image modifications, etc.). This thesis focuses on the application of micro-CT in the field of research and development of metallic and non-metallic materials promoting bone healing with their possible clinical applications. The first part addresses the limitations of micro-CT through several studies. A comparison of pore sizes in biomaterials utilizing scanning electron microscopy (SEM) and micro-CT was performed, and the complications of pore size evaluation were presented. SEM image analysis leads to significantly higher values than micro-CT (approximately three times), which allows for comparison of the studies using only one of these methods. Validation of micro-CT 3D analysis results based on calibration phantoms with complex structure, to date, is not possible. We therefore developed software generating phantom datasets of 3D objects with well-defined...

Ziel der vorliegenden Arbeit war die biologische Charakterisierung neuartiger nanostrukturierter und für die Knochenregeneration geeigneter Calciumphosphatzemente (CPC). Hierzu wurde ein aus α-Tricalciumphosphat, Calciumhydrogenphosphat, gefälltem Hydroxylapatit und Calciumcarbonat bestehender CPC verwendet, der mit den Biomolekülen Cocarboxylase, Glucuronsäure, Weinsäure, Glucose-1-phosphat, Arginin, Lysin und Asparaginsäure-Natriumsalz modifiziert wurde. Ermittelt wurde dabei der Einfluss der Modifikationen auf die Proteinadsorption und die Biokompatibilität. In Vorversuchen wurden die Zementmodifikationen hinsichtlich ihrer Bindungskapazität für humane Serumproteine und für das knochenspezifische Protein Osteocalcin (OC) sowie hinsichtlich ihrer Eignung für die Adhäsion, Proliferation und osteogene Differenzierung von humanen fötalen Osteoblasten (hFOB 1.19) und humanen mesenchymalen Stammzellen (hMSC) untersucht. Dabei erwiesen sich die Modifikationen mit Cocarboxylase, Arginin und Asparaginsäure-Natriumsalz als besonders günstig. Mit diesen „Favoriten“ erfolgte eine detailliertere Analyse der Adsorption humaner und boviner Serumproteine sowie der knochen-spezifischen Proteine Osteocalcin, BMP-2 und VEGF. Dabei führte sowohl der Zusatz von Cocarboxylase, als auch der von Arginin und Asparaginsäure-Natriumsalz zu einer erhöhten Adsorption von Serumproteinen. Die Bindungsaffinität des Basiszements gegenüber Osteocalcin, BMP-2 und VEGF konnte durch Funktionalisierung mit Arginin gesteigert werden. Während die Modifizierung mit Cocarboxylase nur die VEGF-Adsorption förderte, bewirkte der Zusatz von Asparaginsäure-Natriumsalz eine Erhöhung der Osteocalcin- und BMP-2-Adsorption. Bedingt durch die größere spezifische Oberfläche der noch nicht abgebundenen Zemente, war die Menge adsorbierter Proteine auf frisch hergestellten Zementproben im Vergleich zu abgebundenen und ausgehärteten Zementen signifikant höher. Die Eignung der ausgewählten Zementvarianten als Knochenersatzmaterialien wurde mithilfe humaner mesenchymaler Stammzellen zweier verschiedener Spender getestet. Bei Verwendung abgebundener und ausgehärteter Zemente waren die hMSC in der Lage, auf allen Modifikationen zu adhärieren, zu proliferieren und in die osteogene Richtung zu differenzieren. Eine vorherige Inkubation der Zementproben mit humanem Serum förderte dabei vor allem die Zelladhäsion. Weiterhin konnte gezeigt werden, dass hMSC im Gegensatz zu anderen Studien auch auf frisch hergestellten Zementproben adhärieren, proliferieren und differenzieren können. Die Modifizierung des Basiszements mit Cocarboxylase führte hierbei zu einer gegenüber den anderen Modifikationen signifikant erhöhten Zelladhäsion und -vitalität. Neben den verschieden modifizierten Pulver/Flüssigkeitszementen wurden im Rahmen dieser Arbeit neuartige ready-to-use Zementpasten untersucht. Diese zeigten allerdings im Vergleich zu den herkömmlichen Zementen eine geringere Proteinbindungsaffinität. HMSC, die auf den Pastenzementen kultiviert wurden, war es wiederum möglich zu adhärieren, zu proliferieren und den osteoblastenspezifischen Marker Alkalische Phosphatase zu exprimieren. Hinsichtlich ihrer Biokompatibilität sind sie damit vergleichbar zu den herkömmlichen Pulver/Flüssigkeitszementen.

No description available.

Mammals cannot re-form heavily damaged bones as in large fracture gaps, whereas zebrafish efficiently regenerate bones even after amputation of appendages. However, the source of osteoblasts that mediate appendage regeneration is controversial. Several studies in zebrafish have shown that osteoblasts are generated by dedifferentiation of existing osteoblasts at injured sites, but other observations suggest that de novo production of osteoblasts also occurs. In this study, we found from cell-lineage tracing and ablation experiments that a group of cells reserved in niches serves as osteoblast progenitor cells (OPCs) and has a significant role in fin ray regeneration. Besides regeneration, OPCs also supply osteoblasts for normal bone maintenance. We further showed that OPCs are derived from embryonic somites, as is the case with embryonic osteoblasts, and are replenished from mesenchymal precursors in adult zebrafish. Our findings reveal that reserved progenitors are a significant and complementary source of osteoblasts for zebrafish bone regeneration.

No description available.

This doctoral work was developed in the frame of bone tissue engineering, dealing with the fabrication of scaffolds for the regeneration of bones. At this purpose, calcium phosphates derived from natural sources are very interesting because they are more similar to the bone mineral and possess better bioactivity. Indeed, the bone mineral is different from synthetic hydroxyapatite as it is non-stoichiometric, nanosized, it presents a high degree of disorder and contains many additional ions and impurities such as CO32-, Mg2+, Sr2+, Na+, etc. These characteristics can be easily obtained by synthesizing hydroxyapatite from natural sources, such as corals, starfishes, seashells, animal bones, bird eggshells etc. The natural sources used in the present work are three types of biogenic calcium carbonate, i.e. calcium carbonate that is produced by living organisms in the form of aragonite or calcite. Among the different sources, three biogenic calcium carbonates were chosen: cuttlefish (Sepia Officinalis) bones, mussel (Mytilus Galloprovincialis) shells and chicken eggshells. Besides their abundance and availability, they were selected because of their different composition: aragonite in cuttlebones, calcite in eggshells and a mixture of aragonite and calcite in mussel shells. After the first chapter, which is a theoretical introduction, this thesis is divided into other five chapters. Chapter 2 contains a careful characterization of the three biogenic raw materials while Chapter 3 deals with the synthesis of hydroxyapatite starting from these natural sources. The process developed here takes place entirely at nearly room temperature, which allows the organic part of the biological materials to be preserved. This synthesis process is basically a wet mechanosynthesis followed by a mild heat treatment (up to 150°C). The study focuses on the influence of several process parameters on the synthesis efficiency: temperature, milling time, pH and raw material. The temperature used to dry the slurry after the wet ball-milling was found to be the most important parameter, the higher the temperature the faster the conversion of CaCO3 into hydroxyapatite. Moreover, aragonite was found to transform more easily into hydroxyapatite with respect to calcite, and also to follow a different reaction path. The synthesis process described in Chapter 3 allowed to produce different bio-derived powders that were found to be non-stoichiometric, nanosized, carbonated hydroxyapatites, containing also additional ions, especially Mg2+ in the eggshell-derived material and Sr2+ in the cuttlebone-derived one. These powders were then used as a starting point for the studies presented in the next three chapters. Chapter 4 shows a very preliminary evaluation of the interaction with human cells in vitro. First, the as-synthesized powders were consolidated by uniaxial pressing and sintering at temperatures between 900°C and 1100°C and their crystallographic composition was analyzed. Then, after having established the non-cytotoxicity of the sintered pellets, osteoblasts from human osteosarcoma cell line were seeded on the pellets and their behavior after 1, 3 and 5 days of culture was observed by confocal microscopy. In general, all materials promoted good cell adhesion and proliferation, especially the eggshell-derived one. At this point, the bio-derived materials were found to induce a good cellular response but, in order to foster the regeneration of bones, a scaffold must also contain a large amount of interconnected porosity. Among the numerous methods to fabricate porous structures, additive manufacturing is surely very attractive due many advantages, such as the possibility of customizing the shape based on tomography images from the patients, the fact that no mold is needed and the freedom of fully designing the porosity. Indeed, not only the size and the amount of porosity are important, but also the shape of the pores and their position and orientation have a deep effect on the interaction with the cells. Therefore, Chapter 5 and Chapter 6 deal with the fabrication of scaffolds by 3D printing, following two different approaches. In the study presented in Chapter 5, the powders synthesized from cuttlebones, mussel shells and eggshells were used in combination with a thermoplastic polymer (PCL, polycaprolactone) to obtain bioactive composites. Composite materials made of 85 wt% PCL and 15 wt% bio-derived hydroxyapatite were used to fabricate porous scaffolds by extrusion 3D printing. The biological in vitro tests showed that the composite scaffolds possess better bioactivity than the pure PCL ones, especially those containing mussel shell- and cuttlebone-derived powders, which promoted the best cell adhesion, proliferation and metabolic activity of human osteosarcoma cells after 7 days of culture. In addition, the elastic compressive modulus, which was found to be between 177-316 MPa, thus in the range of that of trabecular bone, was found to increase of about ∼50% with the addition of the bio-derived nanopowders. Finally, in Chapter 6, the cuttlebone-derived powder was used to fabricate porous bioceramic scaffolds by binder jetting 3D printing. Due to serious technical issues related to the printing of a nanosized powder, 10 wt% of bio-derived powder was mixed with a glass-ceramic powder with bigger particle size. Moreover, the organic part of the cuttlebone had to be previously eliminated by a heat treatment at 800°C. Thanks to the great freedom of design that is allowed by the binder jetting process, scaffolds with two different pore geometries were fabricated: with pores of uniform size and with a size-gradient. Indeed, natural bone possesses a gradient in porosity from the core to the surface, from porous trabecular bone to dense cortical bone. The sintered scaffolds showed a total porosity of ∼60% for the pure glass-ceramic and ∼70% for the glass-ceramic with 10 wt% of cuttlebone-derived nanoparticles, which most probably slowed down the densification by limiting the contact between the glassy particles. All the bioceramic scaffolds promoted good adhesion and proliferation of human bone marrow-derived mesenchymal stem cells in vitro, without any significant difference between the different samples. However, the scaffolds with the cuttlebone-derived powder and with gradient porosity showed the greatest decrease of metabolic activity after 10 days of culture, which could be accounted as a sign of differentiation of stem cells.

Bone is a remarkable multifunctional tissue with the ability to regenerate and remodel without generating any scar tissue. However, bone loss due to injury or diseases can be a great challenge and affect the patient significantly. Autologous bone grafting is commonly used throughout the world. Autograft both fills the void and is bone inductive, housing the particular cells that are needed for bone regeneration. However, a regenerative complement to autograft is of great interest as the use of biomaterials loaded with bioactive molecules can avoid donor site morbidity and the problem of a limited volume of material. Two such regenerative products that utilise bone morphogenetic protein (BMP)-7 and -2 have been used for more than a decade clinically. Unfortunately, several side effects have been reported, such as severe swelling due to inflammation and ectopic bone formation. Additionally, the products require open surgery and use of supra physiological doses of the BMPs due to poor localisation and retention of the growth factor. The purpose of this thesis was to harness the strong inductive capacity of the BMP-2 by optimising the carrier of this bioactive protein, thereby minimising the side effects that are associated with the clinical products and facilitating safe and localised bone regeneration. We focused on an injectable hyaluronan-based carrier developed through polymer chemistry at the University of Uppsala. The strategy was to use the body’s own regenerative pathway to stimulate and enhance bone healing in a manner similar to the natural bone-healing process. The hyaluronan-based carrier has a similar composition to the natural extracellular matrix and is degraded by resident enzymes. Earlier studies have shown improved properties when adding hydroxyapatite, a calcium phosphate that constitutes the inorganic part of the bone matrix. In Paper I, the aim was to improve the carrier by adding other forms of calcium phosphate. The results indicated that bone formation was enhanced when using nano-sized hydroxyapatite. In Paper II, we discovered the importance of crushing the material, thus enhancing permeability and enlarging the surface area. We wished to further develop the carrier system, but were lacking an animal model with relatively high throughput, facilitated access, paired data, and we were also committed to the 3Rs of refinement, reduction, and replacement. To meet these challenges, we developed and refined an animal model, and this is described in Paper III. In Paper IV, we sought to further optimise the biomaterial properties of the hydrogel through covalent bonding of bisphosphonates to the hyaluronan hydrogel. This resulted in exceptional retention of the growth factor BMP-2. In Paper V, SPECT/PET/µCT was combined as a tri-modal imaging method to allow visualisation of the biomaterial’s in situ action, in terms of drug retention, osteoblast activity and mineralisation. Finally, in Paper VI the correlation between existing in vitro results with in vivo outcomes was observed for an array of biomaterials. The study identified a surprisingly poor correlation between in vitro and in vivo assessment of biomaterials for osteogenesis.

Introdução: As periodontites agressivas (PAg) compõem um grupo de formas rapidamente progressivas da doença periodontal. A restauração do periodonto é um objetivo da terapia periodontal, sendo a regeneração tecidual guiada (RTG) e o uso de substitutos ósseos técnicas bem documentadas. Em pesquisas recentes, foi demonstrado o envolvimento de uma cadeia de 15 aminoácidos do colágeno (P-15) na diferenciação celular de fibroblastos e osteoblastos. A associação de matriz óssea inorgânica bovina com o P-15 (MOI/P-15) tem apresentado bons resultados. O objetivo dessa pesquisa foi avaliar a eficácia da MOI/P-15 no tratamento de defeitos periodontais infra-ósseos em pacientes com periodontite agressiva, tendo como controle o uso de membrana de PTFEe com reforço de titânio Metodologia: Foram selecionados 15 pacientes com PAg, com pelo menos dois defeitos periodontais infra-ósseos (profundidade de sondagem (PS)&ge;4mm e componente infra-ósseo&ge;3mm). Foi adotado o modelo boca dividida, sendo realizadas cirurgias regenerativas com MOI/P-15 (GT) de um lado e membrana de PTFEe (GC) do outro. As medidas clínicas de PS, nível de inserção relativo (NIR) e recessão gengival (RG) foram registradas no exame inicial e após 6 meses. Exames radiográficos padronizados foram feitos no exame inicial e após 3 e 6 meses e radiografias de subtração foram realizadas. Medidas lineares e de área foram registradas. Foram colhidas amostras do fluido gengival antes da cirurgia e aos 3 e 6 meses pós-operatórios e a presença de interleucina 1 beta (IL-1&beta;) e interleucina 6 (IL-6) foi quantificada através de ensaio imunoenzimático. Resultados: Houve redução significativa na PS, de 2,27±0,96 mm (P<0,001) para o GT e de 2,57±1,06 mm para o GC (P<0,001); aumento significativo no NIR, de 1,87±0,94 mm (P<0,001) para o GT e 2,09±0,88 mm (P<0,001) para o GC; e aumento significativo na RG, de 0,58±0,29 mm (P<0,001) para GT e 0,64±0,47 mm (P<0,001) para o GC. Não foram observadas diferenças estatisticamente significantes entre os grupos em nenhum dos parâmetros, tanto no exame inicial quanto após 6 meses. Na análise radiográfica, as radiografias de subtração apresentaram ganho médio de área radiopaca em relação ao defeito inicial de 93,16% para o GT, contra 62,03% para o GC. O preenchimento radiográfico do defeito foi maior (P=0,002). para GT (2,49 mm) que para GC (0.,73 mm). Houve um aumento progressivo da densidade radiográfica para ambos os grupos, sem diferenças estatisticamente significantes. Na análise das citocinas, não foram observadas diferenças estatisticamente significantes nas comparações intra e entre os grupos. Conclusão: No tratamento de defeitos infra-ósseos em pacientes com PAg-G, em um período de 6 meses, não foram observadas diferenças significantes entre as duas modalidades terapêuticas avaliadas (MOI/P-15 e RTG) quanto aos parâmetros clínicos e quantificação de citocinas. GT apresentou preenchimento radiográfico do defeito superior ao apresentado por GC. / Background: Intrabony periodontal defects present a particular treatment problem, especially in patients with Generalized Aggressive Periodontitis (G-AgP).Researches have been performed in order to improve the results of regenerative procedures. Material and Methods: The aim of this study was to compare outcomes of intrabony periodontal defects following treatment with anorganic bone matrix/cell binding peptide (ABM/P-15) to guided tissue regeneration (GTR) in patients with GAgP. Fifteen patients, with two infrabony defects &ge;3 mm deep, were selected for the present study. Patients were allocated randomly to be treated with ABM/P-15 or GTR. At baseline and at 6 months after surgery, clinical and radiographic parameters and IL-1&beta; and IL-6 gingival fluid concentrations were recorded. Results: There was a significant PD reduction (P<0.001) for both groups (2.27±0.96 mm for ABM/P-15 group and 2.57±1.06 mm for GTR group) A CAL gain (1.87±0.94 mm for ABM/P-15 group and 2.09±0.88 mm for GTR group) was observed. In between-group comparisons, there were no statistical significant differences in clinical parameters. The radiographic bone fill was more expressive in ABM/P-15 group (2.49 mm) than in GTR group (0.73 mm). In subtraction radiographs, the areas representing gain in density were 93.16% of the baseline defect for ABM/P-15 group versus 62.03% in GRT group. There were no statiscally significant differences in between and intra-group comparison with regard to IL-1&beta; and IL-6 quantification. Conclusion: Treatment of infrabony periodontal defects in patients with G-AgP with ABM/P-15 and GTR significantly improved clinical outcomes. The use of ABM/P-15 promoted a better radiographic bone fill.

Introdução: A regeneração óssea guiada baseia-se no princípio de seletividade celular, utilizando membranas para impedir a migração de células indesejadas dos tecidos moles e guiar a proliferação de células osteogênicas. A MDA é um biomaterial que tem sido amplamente utilizado em procedimentos regenerativos periodontais, não somente por ser biocompatível, mas também pela sua capacidade reconstrutiva em proporcionar um aumento da faixa de tecido queratinizado. Em pesquisas recentes, foi demonstrado o envolvimento de uma cadeia de 15 aminoácidos do colágeno (P-15) na diferenciação celular de fibroblastos e osteoblastos. A associação de matriz óssea inorgânica bovina com o P-15 (MOI/P-15) tem apresentado bons resultados. O objetivo dessa pesquisa foi avaliar a eficácia da MDA associada à MOI/P-15 na preservação da crista alveolar após extração dentária em humanos. Metodologia: Foram selecionados 18 pacientes que necessitavam de exodontia de dentes anteriores da maxila com pelo menos dois dentes não contíguos. Foi adotado o modelo boca dividida. Após as extrações dentárias foram realizadas cirurgias regenerativas de preservação da crista alveolar utilizando MOI/P-15 (GT) em um alvéolo e o coágulo sanguíneo no outro alvéolo (GC). Após a inserção do substituto ósseo, a MDA foi posicionada e fixada com parafusos sobre os dois alvéolos para servir como membrana. O retalho foi suturado deixando 2 mm da MDA expostos na porção central. As medidas clínicas MVEP, MVEV e MAH foram registradas na primeira cirurgia e após 6 meses, na cirurgia de reentrada, tomando-se como pontos de referência os parafusos de titânio. Resultados Na análise intragrupos, após seis meses, houve redução estatisticamente significante nas medidas MVEP, MVEV e MAH para ambos os grupos. Para o grupo teste, houve redução na MVEP de 2,80 ± 1,61 para 1,97 ± 1,67 mm; na MVEV de 5,80 ± 1,74 para 4,60 ± 2,05 mm e na MAH de 7,40 ± 2,16 para 4,87 ± 1,51 mm. Para o grupo controle, a MVEP variou de 2,50 ± 1,24 para 1,63 ± 1,32 mm; a MVEV de 6,27 ± 1,75 para 4,77 ± 1,59 mm e MAH de 7,60 ± 1,18 para 4,20 ± 1,00 mm. Para a comparação entre os grupos, além das medidas iniciais e finais, foram calculadas as diferenças entre elas para cada grupo. No grupo teste, a diferença para MVEP foi de 0,83 ± 1,53 e no controle foi de 0,87 ± 1,13 mm; e para MVEV foi de 1,20 ± 2,02 e 1,50 ± 1,15 mm para os grupos teste e controle, respectivamente. Na medida horizontal (MAH) foi encontrada diferença estatística quando comparadas as diferenças no grupo teste e controle que foi de 2,53 ± 1,81 mm para o grupo teste e 3,40 ± 1,39 mm para o grupo controle (p<0,05). Conclusão: Os resultados deste estudo mostram que a MDA, associada ou não a MOIP-15, pode ser utilizada com sucesso como membrana para preservação do rebordo alveolar após extração dentária de dentes maxilares anteriores. A associação com o enxerto favorece de maneira significativa a manutenção da espessura no sentido horizontal da crista alveolar. / Background: Preventing ridge collapse with the extraction of maxillary anterior teeth is vital to an esthetic restorative result. Several techniques are available to regenerative procedures and are used for socket preservation. The aim of this study was to analyze by clinical parameters the use of acellular dermal matrix (ADM) and anorganic bovine bone matrix (ABM) with a synthetic cell-binding peptide P-15 to preserve alveolar bone after tooth extraction. Methods: Eighteen patients in need of extraction of maxillary anterior teeth were selected and they were randomly assigned to the test (ADM plus ABM/P-15) or control (ADM only). Clinical measurements were recorded at initial and 6 months after ridge preservation procedures. Results: In the clinical measurements - External Vertical Palatal, External Vertical Buccal and Alveolar Horizontal (EVPM, EVBM and AHM) -, the statistical analysis showed no difference between test and control groups in the initial and at six months. The intragroup analysis, after six months, showed a statistically significant reduction in the measurements for both groups. In the comparison between the groups, the differences (mm), in the test group, were: EVLM=0.83±1.53, EVBM=1.20±2.02, AHM=2.53±1.81 and in the control were: EVLM=0.87±1.13, EVBM=1.50±1.15, AHM=3.40±1.39. The differences in EVLM and EVBM measurements were no statistically significant; however, in horizontal measurement (AHM), there was statistically difference (p<0.05). Conclusion: The results of this study show that ADM, with or without ABM/P-15, can be successfully when it is used as a membrane for preservation of alveolar ridge after tooth extraction of maxillary teeth earlier.