Creeping attachment após enxerto gengival livre: relato de caso / Creeping attachment after autogenous free gingival grafting: case report

Introdução: As técnicas de enxerto gengival livre têm como principal objetivo a criação/aumento da faixa de mucosa ceratinizada. Quando se utiliza o tratamento químico da raiz e o correto posicionamento do enxerto no leito receptor podem acarretar em um fenômeno incomumdenominado de Creeping Attachment. Objetivo: descreverum caso de recobrimento radicular apósum enxerto gengival livre e Creeping Attachment. Relato do caso: Paciente sexo masculino, 28 anos de idade, não fumante e sem alterações sistêmicas apresentouse a faculdade de odontologia Universidade Federal de Santa Catarinacom a queixa principal de comprometimento estético e hipersensibilidade dentinária na região anterior-inferior. No exame clínico verificou-se uma recessão gengival unitária no dente 41, classificada como classe I de Miller. Logo indicou-se a cirurgia de enxerto gengival livre, obtido da região de palato duro, visandouma melhora estética efuncional, bem como a remissão da hipersensibilidade. Conclusão: Diante dos resultados clínicos podemos concluir que o enxerto gengival livre é uma técnica previsível e de fácil realização para o aumentoda faixa de mucosa queratinizada para posterior recobrimento radicular, contudo apesar de incomum o fenômeno Creeping Attachment deve ser esperado como alternativa a etapade recobrimento radicular. (AU)

Introduction: Free gingival graft techniques have as main objective the creation / increase of the keratinized mucosa band. When using the chemical treatment of the root surfaceand the correct positioning of the graft in the recipiente bed can lead to anuncommon phenomenon calledCreeping Attachment. Objective: This scientific paper describes a clinical case of root coverage after a free gingival graft and Creeping Attachment. Case Report: A 28-year-old male patient, non-smoker, was assisted in the Federal University of Santa Catarina by students and teachers of dentistry presented the main complaint the aesthetic impairment and dentin hypersensitivity in the anterior region of the jaw. In the clinical examination was observed an unitary gingival recession in tooth 41, classified as Miller class I. The gingival graft surgery, obtained from the hard palate region, was then indicated to improve the esthetic and functional condition, as well as to promove the end of symptoms of hypersensitivity. Conclusion: Inview of the clinical results we can conclude that the free gingival graft is a predictable and easy to perform technique to increase the line of keratinized mucosa for the subsequent root coverage. However, although the Creeping Attachment phenomenon is uncommon, it should be expected as an alternative to the root coverage (AU)

Preparation and characteristics of drug loaded PLGA chitosan/nano-hydroxyapatite membrane for guided periodontal tissue regeneration in surgical implanting / 第二军医大学学报

Objective To prepare the porous drug-conlaining membrane by poly (ladic-co-glycolic acid) (PLGA)/ chitosan (CS)/nano-hydroxyapatitc for guided periodontal tissue regeneration in surgery, and lo evaluate its performance in vitro. Methods The samples were divided into four groups by different mass ratios of the PLGA lo CS (100: 0, 90: 10, 80: 20 and 70: 30). The PLGA/CS/nano-hydroxyapatitcporous films were prepared by freeze-drying process, wilh polyvinylpyrrolidone (PVP) used as porogcn. The best ratio was chosen by detecting the porosity, water absorption, mechanical properties and degradation of the films; and then il was used as drug carrier lo prepare membrane material for clindamycin controlled release. The morphology of membrane was observed by scan electronmicroscope, (he porosity was detected by anhydrous ethanol liquid displacement method, water absorption was determined by ratio of wet to dry weight of the film, (he wel mechanical performance was tested by electronic universal material testing, (he degradation was determined by weight loss and swelling degree, and the release character was investigated by ultraviolet spcctrophotometric method. In the in vitro experiments, periodontal ligament fibroblast cells (PLFs) were cultured in the membrane for 1-7 days, and cell proliferation was measured by CCK-8. Results The optimal porosity and degradation were found when the mass ratio of PLGA lo CS was 90: 10, wilh the porosity being (28. 66il. 35)%, water absorption being (108. 65 ± 2. 27) %, tensile strength being (2. 36 ± 0. 04) MPa, elongation at break of films being (203.64±3. 89)%, breaking power being (45. 98 ± 2. 46) N, and degradation being (17. 60 ± 0. 86)%. The maximum drug release was 150 μg • mL-1 • d-1, and the effective drug release concentration lasted for 15 d, which could promote the proliferation of PLFs. Conclusion The porous PLGA/CS/nano-hydroxyapatite film prepared in the present study has optimal porosity, its degradation in vitro fit well with the tissue growth, and can create and maintain a specific space for guided periodontal tissue regeneration, allowing for steady drug release for a certain period of time.

Static magnetic fields promote osteoblastic/cementoblastic differentiation in osteoblasts, cementoblasts, and periodontal ligament cells

PURPOSE: Although static magnetic fields (SMFs) have been used in dental prostheses and osseointegrated implants, their biological effects on osteoblastic and cementoblastic differentiation in cells involved in periodontal regeneration remain unknown. This study was undertaken to investigate the effects of SMFs (15 mT) on the osteoblastic and cementoblastic differentiation of human osteoblasts, periodontal ligament cells (PDLCs), and cementoblasts, and to explore the possible mechanisms underlying these effects. METHODS: Differentiation was evaluated by measuring alkaline phosphatase (ALP) activity, mineralized nodule formation based on Alizarin red staining, calcium content, and the expression of marker mRNAs assessed by reverse transcription polymerase chain reaction (RT-PCR). Signaling pathways were analyzed by western blotting and immunocytochemistry. RESULTS: The activities of the early marker ALP and the late markers matrix mineralization and calcium content, as well as osteoblast- and cementoblast-specific gene expression in osteoblasts, PDLCs, and cementoblasts were enhanced. SMFs upregulated the expression of Wnt proteins, and increased the phosphorylation of glycogen synthase kinase-3β (GSK-3β) and total β-catenin protein expression. Furthermore, p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK), and nuclear factor-κB (NF-κB) pathways were activated. CONCLUSIONS: SMF treatment enhanced osteoblastic and/or cementoblastic differentiation in osteoblasts, cementoblasts, and PDLCs. These findings provide a molecular basis for the beneficial osteogenic and/or cementogenic effect of SMFs, which could have potential in stimulating bone or cementum formation during bone regeneration and in patients with periodontal disease.

Novel biological activity of ameloblastin in enamel matrix derivative

Objective Enamel matrix derivative (EMD) is used clinically to promote periodontal tissue regeneration. However, the effects of EMD on gingival epithelial cells during regeneration of periodontal tissues are unclear. In this in vitro study, we purified ameloblastin from EMD and investigated its biological effects on epithelial cells. Material and Methods Bioactive fractions were purified from EMD by reversed-phase high-performance liquid chromatography using hydrophobic support with a C18 column. The mouse gingival epithelial cell line GE-1 and human oral squamous cell carcinoma line SCC-25 were treated with purified EMD fraction, and cell survival was assessed with a WST-1 assay. To identify the proteins in bioactive fractions of EMD, we used proteome analysis with two-dimensional gel electrophoresis followed by identification with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Results Purified fractions from EMD suppressed proliferation of GE-1 and SCC-25. LC-MS/MS revealed that ameloblastin in EMD is the component responsible for inhibiting epithelial cell proliferation. The inhibitory effect of ameloblastin on the proliferation of GE-1 and SCC-25 was confirmed using recombinant protein. Conclusion The inhibitory effects of EMD on epithelial cell proliferation are caused by the biological activities of ameloblastin, which suggests that ameloblastin is involved in regulating epithelial downgrowth in periodontal tissues. .

Dimensional change of the healed periosteum on surgically created defects

PURPOSE: The final goal of regenerative periodontal therapy is to restore the structure and function of the periodontium destroyed or lost due to periodontitis. However, the role of periosteum in periodontal regeneration was relatively neglected while bone repair in the skeleton occurs as a result of a significant contribution from the periosteum. The aim of this study is to understand the histological characteristics of periosteum and compare the native periosteum with the repaired periosteum after elevating flap or after surgical intervention with flap elevation. METHODS: Buccal and lingual mucoperiosteal flaps were reflected to surgically create critical-size, "box-type" (4 mm width, 5 mm depth), one-wall, intrabony defects at the distal aspect of the 2nd and the mesial aspect of the 4th mandibular premolars in the right and left jaw quadrants. Animals were sacrificed after 24 weeks. RESULTS: The results from this study are as follows: 1) thickness of periosteum showed difference as follows (Pflap-elevation group (0.36+/-0.07 mm)>defect formation group (0.26+/-0.03 mm), 2) thickness of gingival tissue showed difference as follows (Pflap-elevation group (2.02+/-0.25 mm)>control group (1.88+/-0.27 mm), 3) higher cellular activity was observed in defect formation group and flap-elevation groups than control group, 4) the number of blood vessles was higher in defect formation group than control group. CONCLUSIONS: In conclusion, prolonged operation with increased surgical trauma seems to decrease the thickness of repaired periosteum and increase the thickness of gingiva. More blood vessles and high cellular activity were observed in defect formation group.

O enxerto de osso em neoformação na era da odontologia baseada em evidências / The newly forming bone autograft in the age of evidence based dentistry

O enxerto de osso em neoformação é uma técnica que visa regeneração periodontal, descrita inicialmente na década de 60 e posteriormente na de 80. Tem a intenção de transportar, em grande quantidade, células vivas capazes de formar osso de um sítio doador, em um alvéolo natural ou artificial, para o defeito ósseo que se deseja tratar. Este trabalho constitui-se em uma revisão da literatura sobre o enxerto ósseo em neoformação, que bjetiva, baseado em evidências científicas, avaliar a eficácia desse tipo de enxerto ósseo, na busca pela regeneração periodontal. Ao buscar referências bibliográficas sobre o assunto, pôde-se perceber que são escassos os estudos que pesquisam o enxerto ósseo em neoformação. Inúmeros são os trabalhos sobre o uso de enxertos ósseos autógenos em periodontia, mas a maioria não chega sequer a citar o enxerto em neoformação. Tal fato nos leva a concluir que esta técnica ainda precisa de comprovação científica acerca de sua real eficácia.

The rewly forming bone autograft is a periodontal regeneration technique described initially in the 60s and later in the 80s. It porposes to carry forming bone cells still alive and in a large amount of a donor site in a natural or artificial socket to a periodontal bone defect. This work is a literature review on the rewly forming bone autograft, which aims, based on scientific evidence, assess the effectiveness of this type of bone graft in the quest for periodontal regeneration. The bibliographic search on the subject, showed that there are few research studies that look at the newly forming bone autograft. Many are the works on other types of bone grafts, but most do not even quote newly forming bone autograft. This fact leads us to conclude that this technique still needs scientific proof of its real effectiveness.

Histological characteristics of newly formed cementum in surgically created one-wall intrabony defects in a canine model

PURPOSE: Periodontal regenerative therapies for defects created by severe periodontitis are mainly focused on bone regeneration. Although cementum regeneration needs to be better understood, it is believed to play an important role in periodontal regeneration. The first step toward a full understanding of cementum regeneration is to compare repaired cementum to pristine cementum. This study, which used histological techniques, was designed to focus on cementum regeneration and to compare pristine cementum to repaired cementum after surgical procedures with 8 and 24 week healing periods in a canine model. METHODS: Buccal and lingual mucoperiosteal flaps of 10 beagle dogs were surgically reflected to create critical-sized defects. Intrabony one-wall defects, of which dimension is 4 mm width and 5 mm depth, were made at the distal aspect of mandibular second premolars and the mesial aspect of mandibular fourth premolars in the right and left jaw quadrants. Animals were sacrificed after 8 and 24 weeks post-surgery for histological specimen preparation and histometric analysis. RESULTS: The repaired cementum was composed mostly of acellular cementum and cellular mixed fiber cementum and was thicker in the apical area than in the coronal area. The acellular cementum of the supracrestal area appeared to be amorphous. The newly formed cellular cementum was partially detached from the underlying circumpulpal dentin, which implied a weak attachment between new cementum and dentin, and this split was observed to a lesser extent in the 24 week group than in the 8 week group. The vertical height of the repaired cementum was greater in the 24 week group than in the 8 week group. CONCLUSIONS: Within the limitations of this study, we can conclude that repaired cementum after root planing was mainly acellular cementum and cementum tissue that matured to a shape similar to pristine cementum as the healing progressed from 8 to 24 weeks.