应用脱细胞真皮基质修复口腔黏膜缺损22例报道

目的：评价脱细胞异体真皮基质组织补片用于口腔黏膜缺损修复的临床效果。方法：对22例因肿瘤手术、外伤、瘢痕、不良增生物切除术及修复前外科等原因引起的口腔黏膜的缺损,应用脱细胞异体真皮基质口腔组织补片进行修复。缺损部位主要为软硬腭、舌、口底、颊部、牙龈、前庭沟等。使用的口腔组织补片面积为1cm×1cm～4cm×6cm。术后随访1周～6个月。结果：共修复22例口腔黏膜缺损,其中2例患者2周后失访。随访的20例病例中,成活18例,脱落2例。术后补片收缩发生在2～4周。2个月后补片较稳定,未发生进一步挛缩。结论：脱细胞真皮基质作为一种黏膜缺损替代品,应用于口腔内各种原因引起的黏膜缺损修复,效果满意。     

釉基质蛋白体外诱导大鼠外胚间充质细胞骨桥素和骨钙素mRNA的表达

目的：了解体外培养环境中，大鼠外胚间充质细胞在两种不同形式釉基质蛋白(粗提型EMPs及纯化型EMD)诱导条件下，成骨分化标志骨桥素及骨钙素mRNA的表达水平。方法：酶消化法原代培养SD大鼠颌突外胚间充质细胞，在含釉基质蛋白(EMPs或EMD或EMPs EMD)的培养液中进行体外诱导培养，提取总RNA，采用RT-PCR法，以β-actin cDNA为内参照，检测骨桥素及骨钙素mRNA的表达水平。结果：1)各诱导实验组细胞均出现骨桥素mRNA的表达；2)仅EMPs EMD组出现骨钙素mRNA的表达。结论：外胚间充质细胞经釉基质蛋白特别是粗提型EMPs及纯化型EMD体外复合和诱导培养，可向成骨或成牙骨质方向分化，出现骨桥素及骨钙素mRNA的表达。     

Dentin induction by implants of autolyzed antigen-extracted allogeneic dentin on amputated pulps of dogs

Abstract Implantation of autolyzed antigen-extracted allogeneic (AAA) dentin matrix gelatin powder caused homeoinduction on amputated dental pulps. This event began with migration of spindle-shaped mesenchymal cells into the cavity on the amputated pulp. This was followed by proliferation of undifferentiated large cells concomitantly with vascular invasion and attachment of spindle-shaped cells and large cells to the AAA dentin. The adhering cells differentiated into osteodentinoblasts and/or preodontoblasts to form osteodentin matrix and predentin respectively. Osteodentinocytes and odontoblasts, then, formed osteodentin and tubular dentin. The healing of pulp dressed with inactivated AAA dentin using guanidine HCl was delayed. These results suggested that AAA dentin matrix powder may have chemotactic and mitogenic activity for undifferentiated mesenchymal cells and may provide a suitable scaffolding for fixation of these cells. Compartments of microenvironment formed by AAA dentin and the enveloping hard substances may play some role in differentiation into odontoblasts.     

Histopathological changes in collagen and matrix metalloproteinase levels in articular condyle of experimental model rats with jaw deformity

OBJECTIVE: To investigate the dynamics of the cartilage matrix in the articular condyle after removal of a side shift plate; Emergence of type I, II, and III collagen in the matrix as well as changes in levels of matrix metalloproteinase (MMP)-1, -8, and -13 that degrade collagen were studied histopathologically and immunohistochemically. DESIGN: Lateral displacement of the mandible was achieved by attaching a side shift plate to the anterior teeth of the maxilla in male rats at 6 weeks. The wearing period of the side shift plate was 8 weeks. Observations were made at 0, 1, 2, 4 and 8 weeks after removal. RESULTS: In histopathological findings, the timing of proliferation of the layer of hypertrophy varied between the bilateral sides. In immunohistochemical findings a significant decline in the expression of type II collagen in the displacement side was observed immediately after removal. Moreover, the expressions of MMPs were elevated in both sides on 0 weeks. At 1 week after removal, a significant elevated in the expression of type II collagen, MMPs was decline in both sides. CONCLUSIONS: After removal, the levels of MMP-1, -8, and 13 were reduced and the emergence of type II collagen increased. Thus, cellular outgrowth was initiated to trigger intracartilaginous ossification to restore the cartilage matrix.     

A clinical study evaluating the treatment of supra-alveolar-type defects with access flap surgery with and without an enamel matrix protein derivative: a pilot study

Aim: There is evidence that regenerative treatment of intra-bony and mandibular class II furcation defects with access flap and an application of an enamel matrix protein derivative (EMD) can result in a clinical benefit compared with access flap alone. The aim of this pilot study was to check if the results of access flap surgery in suprabony defects are improved by additional application of EMD.
Material and Methods: Thirty-nine adult subjects with supra-alveolar-type defects were randomly assigned to a test ( n =25) and a control group ( n =14). Seventy teeth were treated with EMD; 28 teeth were treated by access flap. Probing depth (PD), clinical attachment level and bleeding on probing were evaluated at baseline and after 12 months.
Results: PD of the operated teeth was improved in both groups ( p <0.001 to p =0.041) but always better in the test group. The attachment gain was 2.72±1.80 mm at sites with an initial PD 7 mm in the test group and 0.78±0.62 mm in the control group ( p =0.004). In the test group the mean attachment gain was 0.97±0.92 mm ( p <0.001); the mean reduction of PD was 1.55±0.90 mm ( p <0.001).
Conclusions: The data suggest a significant clinical benefit of supplementary application of EMD during surgical treatment of periodontitis of supra-alveolar pockets, especially in deeper pockets.     

Critical features of periodontal flaps with regard to blood clot stability: A review

BackgroundWound healing is a multifactorial procedure involving different cell types and biological mediators. The principles of wound healing are also applicable to periodontal tissues. The formation and stability of blood clots play a vital role in successful healing of wounds in periodontal tissues. The aim of the present review was to highlight the vital factors of periodontal flaps associated with blood clot stability.HighlightThe data on periodontal regeneration and wound healing have evolved greatly in light of several factors, including space for blood clots and blood clot stabilization. In periodontal osseous defects, the stability of blood clots seems critical to wound healing. If mechanical forces can be managed by wound stabilization, the gingival flap-tooth root interface may show connective tissue repair. However, compromised adhesion is susceptible to mechanical forces and can cause wound breakage and epithelialization.ConclusionThe presence of a thick blood clot may hinder the plasmatic circulation between the recipient bed and graft during the initial stage of healing, which is critical in cases of mucogingival surgery. Root conditioning can also determine the healing consequence by enhancing blood clot adhesion.     

Five-year results following treatment of intrabony defects with enamel matrix proteins and guided tissue regeneration

BACKGROUND: Treatment with enamel matrix proteins (EMD) or guided tissue regeneration (GTR) has been shown to enhance periodontal regeneration. However, until now there are limited data on the long-term results following these treatment modalities. Aim: The aim of the present clinical study was to present the 5-year results following treatment of intrabony defects with EMD, GTR, combination of EMD and GTR, and open flap debridement (OFD). MATERIAL AND METHODS: Forty-two patients, each of whom displayed one intrabony defect of a probing depth of at least 6 mm, were randomly treated with one of the four treatment modalities. The following parameters were evaluated prior to surgery, at 1 year and at 5 years after: plaque index, gingival index, bleeding on probing, probing pocket depth (PPD), gingival recession, and clinical attachment level (CAL). No statistically significant differences in any of the parameters were observed at baseline between the four groups. RESULTS: The sites treated with EMD demonstrated a mean CAL gain of 3.4+/-1.1 mm (p<0.001) and of 2.9+/-1.6 mm (p<0.001) at 1 and 5 years, respectively. The sites treated with GTR showed a mean CAL gain of 3.2+/-0.8 (p<0.001) at 1 year and of 2.7+/-0.9 mm (p<0.001) at 5 years. The mean CAL gain at sites treated with EMD+GTR was 3.0+/-1.0 mm (p<0.001) and 2.6+/-0.7 mm (p<0.001) at 1 and 5 years, respectively. The sites treated with OFD demonstrated a mean CAL gain of 1.6+/-1.0 mm (p<0.001) at 1 year and 1.3+/-1.2 mm (p<0.001) at 5 years. At 1 year, the only statistically significant difference between the four different treatments was found in terms of PPD reduction and CAL gain between EMD and OFD (p<0.05). However, at 5 years there were no statistically significant differences in any of the investigated parameters between the four different treatments. CONCLUSION: Within the limits of the present study, it may be concluded that the short-term clinical results following treatment with EMD, GTR, EMD+GTR, and OFD can be maintained over a period of 5 years.     

Autogenous bone graft in conjunction with enamel matrix derivative in the treatment of deep periodontal intra-osseous defects: a report of 13 consecutively treated patients

AIM: The purpose of the present study was to investigate the effectiveness of a regenerative procedure based on supra-crestal soft tissue preservation in association with combined autogenous bone (AB) graft/enamel matrix derivative (EMD) application in the treatment of deep periodontal intra-osseous defects. METHODS: Thirteen consecutively treated patients, seven females and six males, aged 30-65 years, three smokers, were included. A total of 15 deep, one- to two-wall intra-osseous defects were selected. Immediately before surgery and 6 months after surgery, pocket probing depth (PPD), clinical attachment level (CAL), and gingival recession (REC) were recorded. RESULTS: PPD amounted to 9.4+/-1.8 mm before surgery, and decreased to 4.7+/-1.2 mm post-surgery (p<0.0000). CAL varied from 10.5+/-2.0 mm pre-surgery to 6.2+/-1.7 mm post-surgery (p<0.0000), with CAL gain averaging 4.3+/-1.4 mm. Fourteen (93.3%) defects presented CAL gain >/=3 mm. REC change was 0.4+/-0.7 mm. CONCLUSIONS: Results from the present study indicated that a regenerative procedure based on supra-crestal soft tissue preservation and combined AB/EMD treatment leads to a clinically and statistically significant improvement of soft tissue conditions of deep periodontal intra-osseous defects.     

Biomimetic Approach to Perforation Repair Using Dental Pulp Stem Cells and Dentin Matrix Protein 1

Introduction

Dentin regeneration could be an ideal treatment option to restore tissue function. This study was conducted to evaluate the ability of dental pulp stem cells (DPSCs) and dentin matrix protein 1 (DMP1) impregnated within a collagen scaffold to regenerate dentin.

Methods

Simulated perforations were created in 18 dentin wafers made from freshly extracted human molars. Six groups were established. They were (1) empty wafers, (2) mineral trioxide aggregate, (3) collagen scaffold, (4) scaffold with DMP1, (5) scaffold with DPSCs, and (6) scaffold with DPSCs and DMP1. One sample was placed subcutaneously in each mouse with three mice in each group. After 12 weeks, the samples were subjected to radiographic, histological, and immunohistochemical evaluations.

Results

DPSCs impregnated within a collagen scaffold differentiated into odontoblast-like cells forming a highly cellular, vascular, and mineralized matrix in the presence of DMP1.

Conclusions

A triad consisting of DPSCs, DMP1, and a collagen scaffold promotes dentin regeneration in a simulated perforation repair model.