RESUMO
Stimulation of neoosteogenesis is the main mechanism of osseointegration during installation of dental implants, bone tissue recession, and alveolar process augmentation in adentia. In experiments on miniature pigs, we used the technology of two-stage splitting of the ridge of the alveolar process of the mandible in combination with a xenograft that was placed between the fragments of the split bone plate. The morphology of the reparative process and the distribution of osteogenic differentiation markers in the compact and trabecular bone of the alveolar crest were studied. Signs of reparative osteogenesis were observed in the bone regenerate that had a lamellar structure, formed osteons, and foci of woven tissue. It was found that the xenograft was replaced by newly formed trabecular bone tissue. These sites were characterized by increased expression of osteocalcin and CD44. Augmentation technology through two-stage splitting provides trophic relationship of osteoprogenitor cells and is an effective method of osteogenesis stimulation in the alveolar process.
Assuntos
Aumento do Rebordo Alveolar , Humanos , Animais , Suínos , Aumento do Rebordo Alveolar/métodos , Osteogênese/fisiologia , Transplante Ósseo/métodos , Processo Alveolar/cirurgia , Osseointegração/fisiologia , Mandíbula/cirurgiaRESUMO
We examined alveolar bone samples in the area of on-bone fixation of a free gingival graft performed during surgery in patients aged 37-55 years with a diagnosis of secondary partial adentia of the upper and lower jaws. Six months after fixation of the graft in the alveolar bone, foci of neoosteogenesis were found in the contact zone. They were characterized by the appearance of appositional lines, cords of basophilic osteoblasts, and growing osteons. An immunohistochemical study revealed an increase in the number of CD44+, CD29+, and osteocalcin+ cells in the layer of the outer circumferential lamellae, primary osteons, and the lining of the Haversian canals. TGF-ß1+ cells were located in the intertrabecular reticular tissue and wall of microvessels. The results indicate activation of mesenchymal stem cells in the area of localization of the graft and differentiating osteoblasts. The observed osteoinductive effect of free gingival graft is associated with its participation in reorganization in MSC and induction of morphogenetic molecules.
Assuntos
Processo Alveolar/fisiologia , Implantação Dentária/métodos , Gengiva/transplante , Arcada Parcialmente Edêntula/terapia , Osseointegração/fisiologia , Adulto , Enxerto de Osso Alveolar/métodos , Processo Alveolar/citologia , Aumento do Rebordo Alveolar/métodos , Remodelação Óssea/genética , Diferenciação Celular/genética , Feminino , Retalhos de Tecido Biológico/fisiologia , Gengiva/metabolismo , Gengiva/patologia , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Arcada Parcialmente Edêntula/genética , Arcada Parcialmente Edêntula/patologia , Arcada Parcialmente Edêntula/fisiopatologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Pessoa de Meia-Idade , Osseointegração/genética , Osteocalcina/genética , Osteocalcina/metabolismo , Osteogênese/genética , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismoRESUMO
We studied immunolocalization of CD29, CD44, osteocalcin, and TGF-ß1 in the bone tissue of the mandible of miniature pigs with extra-bone fixation of a free gingival graft. Three months after surgery, neoosteogenesis foci with high expression of the studied markers were found in the contact area of the free gingival graft with the alveolar bone. The markers were localized in the layer of external circumferential lamellae, on the surface of concentric lamellae of the growing osteons, and in the connective tissue of the Haversian canals. TGF-ß1-immunopositive cells predominated in the connective tissue of the Haversian and Volkmann canals and in the adventitia and inner lining of the vascular wall. The established morphochemical patterns of osteogenous cells indicate significant reparative capabilities of a free gingival graft and allows considering it as an effective osteoinductive factor.
Assuntos
Enxerto de Osso Alveolar/métodos , Gengiva/transplante , Mandíbula/cirurgia , Osteogênese/genética , Regeneração/genética , Transplantes/fisiologia , Enxerto de Osso Alveolar/instrumentação , Animais , Biomarcadores/metabolismo , Pinos Ortopédicos , Expressão Gênica , Gengiva/cirurgia , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Masculino , Osteocalcina/genética , Osteocalcina/metabolismo , Dispositivos de Fixação Cirúrgica , Suínos , Porco Miniatura , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Transection of the maxillary nerve initiates apoptosis of the maxillary sinus mucosa cells in rats. Significant activation of apoptosis and proapoptotic factor p53 was found in the epithelium during week 1 after nerve transection. In delayed period after injury, apoptotic cells predominated in the submucosa against the background of Bcl-2 hypoexpression.
Assuntos
Apoptose/fisiologia , Nervo Maxilar/fisiopatologia , Seio Maxilar/citologia , Mucosa Nasal/lesões , Traumatismos do Nervo Trigêmeo/fisiopatologia , Animais , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Nervo Maxilar/lesões , Seio Maxilar/lesões , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Proteína Supressora de Tumor p53/metabolismoRESUMO
Histotopography of the maxillary sinus in the nasal compartment of the rat head was studied. Anatomical parameters of the sinus were determined, histological structure of the mucosa described, and similarity with organization of human maxillary sinus was revealed.
