ABSTRACT
Background: It is known that a large number of mediators involved in osteogenesis can influence bone development and repair; however, whether these mediators could be used as markers of bone maturity has yet to be determined. Aim: To evaluate the expression of osteocalcin (OC) and Runt-related transcription factor 2 (Runx2) in bone biopsies obtained during the reconstruction of atrophic anterior maxillae using particulate bone xenografts with or without association of autogenous bone marrow aspirate concentrate (BMAC). Materials and Methods: Ten patients were distributed into two groups (n = 5), according to the type of grafting material used: Control group (CG), particulate bone xenograft alone, and test group (TG), particulate bone xenograft combined with BMAC. A bone specimen was removed from the graft area 4 months after grafting, before implant placement. The specimens were processed and submitted to immunohistochemical analysis for detection of OC and Runx2. Histomorphometry was used to ascertain the percentage of stained areas in both groups. The Wilcoxon Mann-Whitney U-Test was used in the statistical analysis (P < 0.05). Results: The immunohistochemical analysis revealed a significantly higher OC expression in the TG than in the CG, namely 27.40 ± 1.34% and 11.40 ± 2.70%, respectively (P < 0.05), and a significantly higher Runx2 expression in the TG than in the CG, namely 2.80 ± 0.84% and 0.40 ± 0.55%, respectively (P < 0.05). Conclusion: The OC and Runx2 expression levels were higher when BMAC was associated with the bone xenograft than when it was not.
ABSTRACT
A busca de técnicas e de materiais para reconstrução do tecido ósseo é constante. Atualmente, o osso autógeno é considerado o padrão ouro. Enxertos ósseos homógenos surgiram como alternativa, principalmente quando é necessária grande quantidade de material para enxertia e quando da impossibilidade de um segundo sítio cirúrgico. Já a técnica de tunelização modificada visa o restabelecimento da estrutura óssea, com menores danos aos tecidos e com menor tempo cirúrgico, o que não ocorre nas demais técnicas. Paciente de 64 anos, sexo masculino, apresentava reabsorção avançada da maxila e não desejava submeter-se a cirurgias em nível hospitalar e/ou remover tecido ósseo autógeno de regiões doadoras possíveis. Decidiu-se pela realização de enxertia óssea maxilar total através da Técnica de Tunelização modificada com a utilização de osso homógeno proveniente de banco de ossos. Após 10 meses da intervenção cirúrgica foi observado clínica e tomograficamente ganho ósseo considerável em altura e largura permitindo o planejamento cirúrgico para a colocação de implantes dentários. Concluiu-se que na impossibilidade do uso de osso autógeno a utilização de osso homógeno é um procedimento possível e que deve ser levado em consideração, porque possibilita uma menor morbidade devido a não necessidade de um segundo sítio cirúrgico e possibilita a obtenção de grande quantidade de material enxertivo. Já a técnica de tunelização modificada é de fácil execução permitindo menor tempo cirúrgico e pequena morbidade, o que revela o grande significado desta técnica e a importância de sua incorporação ao rol de procedimentos enxertivos já existentes...
The search for techniques and materials for reconstruction of bone tissue is constant. Currently, autogenous bone is considered the golden standard, but homogenous bone grafts have emerged as an alternative, especially when a large amount of material for grafting is needed and when a second surgical site is not viable. The modified tunnelling technique aims to restore the bone structure, with less tissue damage and lower surgical time, which is not possible through other techniques. A 64 year-old male patient had advanced resorption of the maxilla and did not want to undergo a surgery performed in a hospital and/or obtain autogenous bone tissue from possible donor regions. Thus, the choice for full maxillary bone grafting was made, and the modified tunnelling technique was applied using homogenous bone from a bone tissue bank. Ten months after surgery, a considerable bone gain, both bone height and bone width, was observed clinically and tomographically, thus allowing a better surgical planning for the placement of dental implants. Given the impossibility of obtaining autogenous bone, the use of homogenous bone is a viable alternative that should be taken into account. Not only does it enable lower morbidity, since there is no need for a second surgical site, but it also enables the acquisition of large amounts of grafting materials. Moreover, the modified tunnel technique shows a number of advantages: it is an easy, minimally invasive procedure, allowing less surgical time, and low morbidity, which demonstrates the significant importance of its incorporation into the list of existing grafting techniques...
