纤维调节素在人类牙周细胞损伤愈合中的免疫组织化学表达

目的研究纤维调节素在牙周细胞损伤愈合中的表达,探讨纤维调节素在牙周损伤愈合中的作用。方法培养人类牙周细胞（牙龈成纤维细胞、牙周膜成纤维细胞和成骨细胞）;在培养了牙周细胞的载玻片上做损伤细胞的圆形创口,建立牙周细胞损伤模型,跟踪观察7 d;用免疫组织化学染色的方法,观察纤维调节素在牙周细胞损伤愈合过程中的表达。结果牙周细胞损伤后第1天,纤维调节素较强表达于损伤边缘新移行的细胞;随后,纤维调节素对损伤区新近移行的细胞的表达强于创口周围的细胞。结论纤维调节素强烈表达于损伤区新近移行的牙周细胞,可能参与牙周损伤愈合的早期活动。     

Relation between wound healing after surgery and susceptibility to periodontal disease

Abstract. In the present investigation wound healing was studied clinically in 8 younger (mean age 33.5 years) and 8 older patients (mean age 48 years), who were surgically treated for the same amount of severe periodontitis. This implies that the patients in the younger age group represented individuals with a higher degree of susceptibility to periodontal disease than the patients in the older age group. After surgery all patients were subjected to a carefully controlled oral hygiene program. Patients were recalled weekly until 8 weeks post surgery and again after 15 weeks for a final examination. At every recall session oral hygiene measurements were carried out and the bleeding tendency of the pockets was determined after probing with a standardized pressure. Bleeding on the basis of mechanical trauma after probing was considered to be a clinical parameter for wound healing in a plaque free environment.
Results indicate that the oral hygiene program resulted in equally low plaque scores in both age groups. However, in a period from 5–15 weeks after surgery younger patients showed significantly more bleeding pockets than older patients. Furthermore it was found in both groups that the more loss of attachment there was, the slower the rate of wound healing.
It was concluded that the time span for wound healing is longer in patients who are more susceptible to periodontal disease, than in those who are less susceptible.     

一种牙周细胞体外创面愈合模型的构建

目的:构建一种可用于牙周组织创面愈合规律研究的体外创面愈合模型,比较牙周膜细胞和牙龈成纤维细胞覆盖体外创面的速度。方法:体外培养人牙周膜、牙龈成纤维细胞至玻片上各自形成单层融合。以机械方法刮除部分融合层细胞,构成25mm×7mm的无细胞区域,即牙周细胞体外创面。创面形成后继续于100mL/L胎牛血清环境下培养2、6、9d。玻片细胞固定后以结晶紫染色。以计算机辅助图像分析系统对创面特定区域采图,进行细胞覆盖面积定量和统计分析。结果:在所构建牙周细胞体外创面上牙龈成纤维细胞的覆盖速度高于牙周膜细胞。创面形成后第9天,牙龈成纤维细胞覆盖采图区域面积的百分比均数为62.26%,牙周膜细胞则为44.15%,差异有显著性(P<0.05)。结论:实验以细胞覆盖创面面积综合衡量细胞增殖和移动能力,在实验构建的牙周细胞体外创面模型上,牙龈成纤维细胞覆盖创面速度高于牙周膜细胞,能够体现两者在覆盖创面能力上的差异。实验构建的体外创面模型可用于牙周细胞创面愈合能力的研究,对探讨牙周组织创面愈合机制及其调控规律有所裨益。     

One-year outcomes of repeated adjunctive photodynamic therapy during periodontal maintenance: a proof-of-principle randomized-controlled clinical trial

Background: Single photodynamic therapy (PDT) has been effective in initial periodontal therapy, but only improved bleeding on probing (BoP) in maintenance patients after a single use. Repeated PDT has not been addressed.
Objectives: To study the possible added benefits of repeated adjunctive PDT to conventional treatment of residual pockets in patients enrolled in periodontal maintenance.
Material and Methods: Ten maintenance patients with 70 residual pockets [probing pocket depth (PPD)5 mm] were randomly assigned for treatment five times in 2 weeks (Days 0, 1, 2, 7, 14) with PDT (test) or non-activated laser (control) following debridement. The primary outcome variable was PPD, and the secondary variables were clinical attachment level (CAL) and BoP. These were assessed at 3, 6 and 12 months following the interventions.
Results: Greater PPD reductions were observed in the test (−0.67 ± 0.34; p =0.01) compared with the control patients (−0.04 ± 0.33; NS) after 6 months. Significant CAL gain (+0.52 ± 0.31; p =0.01) was noted for the test, but not in the control (−0.27 ± 0.52; NS) patients after 6 months. BoP percentages dcreased significantly in test (97–64%, 67%, 77%), but not control patients after 3, 6 and 12 months.
Conclusions: Repeated (five times) PDT adjunctive to debridement yielded improved clinical outcomes in residual pockets in maintenance patients. The effects were best documented after 6 months.     

Periodontal dressing after surgical crown lengthening: A randomized clinical trial

Objective. The aim of the present study was to evaluate the effect of periodontal dressing on post-operative pain and swelling after surgical crown lengthening. Materials and methods. A blind, randomized, clinical trial was carried out with 36 patients. Following surgical crown lengthening, the individuals were randomly allocated to the periodontal dressing group (PDG) and control group (CG, non-placement of periodontal dressing). Pain and discomfort were analyzed using a visual analog scale (VAS), verbal scale (VS) and the number of analgesics consumed in 7 days post-operatively. Post-operative infection, stability of the gingival margin and type of healing were also evaluated. Results. The PDG had a significantly higher percentage of responses of ‘strong pain’ on the VS in the first day post-operatively (33.3% vs 5.3%, p = 0.03) and greater pain on the first and second days post-operatively based on the VAS. Moreover, a significant difference between groups was found regarding gingival swelling after 7 days. However, gingival recession was found in 57.8% of the sites in the CG and only 5.5% of sites in the PDG. No change in condition was found among individuals with conjunctive tissue/bone exposure in the CG in the immediate post-operative period and 80% of the patients in the PDG had healing by first intention after 7 days. Conclusion. The use of periodontal dressing seems to be preferable following surgical crown lengthening with connective tissue/bone exposure. However, adequate post-operative analgesic strategies should be employed due to the possibility of intense pain in the first 24 hours.     

Enamel matrix derivative and low-level laser therapy in the treatment of intra-bony defects: a randomized placebo-controlled clinical trial

Aim: The aim of this study was to evaluate the immediate post‐operative pain, wound healing and clinical results after the application of an enamel matrix protein derivative (EMD) alone or combined with a low‐level laser therapy (LLLT) for the treatment of deep intra‐bony defects. Material and Methods: This study was an intra‐individual longitudinal test of 12 months' duration conducted using a blinded, split‐mouth, placebo‐controlled and randomized design. In 22 periodontitis patients, one intra‐bony defect was randomly treated with EMD+LLLT, while EMD alone was applied to the contra‐lateral defect site. LLLT was used both intra‐ and post‐operatively. Clinical measurements were performed by a blinded periodontist at the time of surgery, in the first week and in the first, second, sixth and 12th month. Visual analogue scale (VAS) scores were recorded for pain assesment. Results: The results have shown that the treatment of intra‐bony defects with EMD alone or EMD+LLLT leads to probing depth reduction and attachment‐level gain. In addition, EMD+LLLT had resulted in less gingival recession (p<0.05), less swelling (p<0.001) and less VAS scores (p<0.02) compared with EMD alone. Conclusion: This study shows that EMD is an effective, safe and predictable biomaterial for periodontal regeneration and LLLT may improve the effects of EMD by reducing post‐operative complications.     

低能量激光治疗在牙周组织愈合中的作用

近年来激光在口腔医学领域的应用日益广泛。在牙周治疗中,激光可用来进行牙结石去除、根面处理、软组织及骨修整等,参与到牙周治疗的各个环节,起到很好的辅助牙周治疗作用。低能量激光是指能量较温和、治疗时不产生热量的一类激光。在牙周治疗时可利用其生物刺激功能起到抑制牙周炎症、促进创口愈合及牙周组织再生等方面的作用。文章主要介绍低能量激光的特点、作用机制及临床使用方法,为低能量激光治疗在临床的进一步推广应用提供思路。     

Low-intensity pulsed ultrasound accelerates periodontal wound healing after flap surgery

Background and Objective:  A study was conducted to evaluate the effects of low-intensity pulsed ultrasound on wound healing in periodontal tissues after mucoperiosteal flap surgery.
Material and Methods:  Bony defects were surgically produced bilaterally at the mesial roots of the mandibular fourth premolars in four beagle dogs. The flaps were repositioned to cover the defects and sutured after scaling and planing of the root surface to remove cementum. The affected area in the experimental group was exposed to low-intensity pulsed ultrasound, daily for 20 min, for a period of 4 wk from postoperative day 1 using a probe, 13 mm in diameter. On the control side, no ultrasound was emitted from the probe placed contralaterally. After the experiment, tissue samples were dissected out and fixed in 10% formalin for histological and immunohistochemical analyses.
Results:  The experimental group showed that the processes in regeneration of both cementum and mandibular bone were accelerated by low-intensity pulsed ultrasound compared with the control group. In addition, the expression level of heat shock protein 70 was higher in the gingival epithelial cells of the low-intensity pulsed ultrasound-treated tooth.
Conclusion:  Our results suggest that osteoblasts, as well as cells in periodontal ligament and gingival epithelium, respond to mechanical stress loaded by low-intensity pulsed ultrasound, and that ultrasound accelerates periodontal wound healing and bone repair.     

Differential expression and distribution of syndecan-1 and -2 in periodontal wound healing of the rat

Cell-surface proteoglycans participate in several biological functions including interactions with adhesion molecules, growth factors and a variety of other effector molecules. Accordingly, these molecules play a central role in various aspects of cell-cell and cell-matrix interactions. To investigate the expression and distribution of the cell surface proteoglycans, syndecan-1 and -2, during periodontal wound healing, immunohistochemical analyses were carried out using monoclonal antibodies against syndecan-1, or -2 core proteins. Both syndecan-1 and -2 were expressed and distributed differentially at various stages of early inflammatory cell infiltration, granulation tissue formation, and tissue remodeling in periodontal wound healing. Expression of syndecan-1 was noted in inflammatory cells within and around the fibrin clots during the earliest stages of inflammatory cells infiltration. During granulation tissue formation it was noted in fibroblast-like cells and newly formed blood vessels. Syndecan-1 was not seen in newly formed bone or cementum matrix at any of the time periods studied. Syndecan-1 expression was generally less during the late stages of wound healing but was markedly expressed in cells that were close to the repairing junctional epithelium. In contrast, syndecan-2 expression and distribution was not evident at the early stages of inflammatory cell infiltration. During the formation of granulation tissue and subsequent tissue remodeling, syndecan-2 was expressed extracellularly in the newly formed fibrils which were oriented toward the root surface. Syndecan-2 was found to be significantly expressed on cells that were close to the root surface and within the matrix of repaired cementum covering root dentin as well as at the alveolar bone edge. These findings indicate that syndecan-1 and -2 may have distinctive functions during wound healing of the periodontium. The appearance of syndecan-1 may involve both cell-cell and cell-matrix interactions, while syndecan-2 showed a predilection to associate with cell-matrix interactions during hard tissue formation.     

Periodontal repair in dogs: effect of rhBMP-2 concentration on regeneration of alveolar bone and periodontal attachment

The objective of this study was to evaluate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) concentration on regeneration of alveolar bone and cementum, and on associated root resorption and ankylosis. Contralateral, critical size, supra-alveolar, periodontal defects were surgically produced and immediately implanted with rhBMP-2 in an absorbable collagen sponge (ACS) carrier in 8, young adult, male, beagle dogs. 6 animals received rhBMP-2/ACS (rhBMP-2 at 0.05, 0.10, or 0.20 mg/mL; total construct volume/defect approximately 4.0 mL) in contralateral defects following an incomplete block design. 2 animals received rhBMP-2/ACS (rhBMP-2 at 0 and 0.10 mg/mL) in contralateral defects (controls). The animals were euthanised at 8 weeks post-surgery and block sections of the defects were collected for histologic and histometric analysis. Supra-alveolar periodontal defects receiving rhBMP-2 at 0.05, 0.10, or 0.20 mg/ml exhibited extensive alveolar regeneration comprising 86%, 96%, and 88% of the defect height, respectively. Cementum regeneration encompassed 8%, 6%, and 8% of the defect height, respectively. Root resorption was observed for all rhBMP-2 concentrations. Ankylosis was observed in almost all teeth receiving rhBMP-2. Control defects without rhBMP-2 exhibited limited, if any, evidence of alveolar bone and cementum regeneration, root resorption, or ankylosis. Within the selected rhBMP-2 concentration and observation interval, there appear to be no meaningful differences in regeneration of alveolar bone and cementum. There also appear to be no significant differences in the incidence and extent of root resorption and ankylosis, though there may be a positive correlation with rhBMP-2 concentration.     

The effect of subantimicrobial-dose-doxycycline periodontal therapy on serum biomarkers of systemic inflammation: a randomized, double-masked, placebo-controlled clinical trial

BackgroundPeriodontitis has been reported to be associated with coronary artery disease (CAD). Research is needed to determine if therapies that improve periodontal health also reduce systemic measures of inflammation associated with both diseases.MethodsThe study registrar randomly assigned 128 eligible postmenopausal women with chronic periodontitis to a twice-daily regimen of subantimicrobial-dose–doxycycline (SDD) or placebo tablets for two years as an adjunct to periodontal maintenance therapy. Through a supplement to the main trial, in which they investigated alveolar bone and clinical attachment level changes, the authors assayed inflammatory mediators and lipid profiles in baseline, one-year and two-year serum samples. The authors analyzed the data by using generalized estimating equations.ResultsIn the intent-to-treat analysis across two years, SDD treatment reduced median high-sensitivity C-reactive protein (hs-CRP) by 18 percent (primary outcome; P = .02) and reduced serum matrix metalloproteinase (MMP)-9 (92 kilodalton gelatinase; difference in mean scanning units, ?28.44; P < .001), with no significant effect on serum lipids. However, in women more than five years postmenopausal, SDD elevated the level of high-density lipoprotein (HDL) cholesterol (difference in means [milligrams per deciliter], 5.99; P = .01).ConclusionA two-year SDD regimen in postmenopausal women significantly reduced the serum inflammatory biomarkers hs-CRP and MMP-9 and, among women more than five years postmenopausal, increased the HDL cholesterol level.Clinical ImplicationsSDD significantly reduced the systemic inflammatory biomarkers hs-CRP and MMP-9. More research is needed to determine whether SDD has a role in managing the care of patients at risk of developing CAD.     

Protection of an intraoral surgical wound with a new dressing: a randomised controlled clinical trial

Operations that involve the maxillofacial region often require intraoral incisions, and contamination of these wounds is common as a result of the presence of saliva, plaque, and food debris. Postoperative infection is therefore common. The aim of the study was to evaluate the clinical efficacy of an intraoral dressing material, Reso-Pac®, in improving postoperative comfort for patients and its effect on wound healing. One hundred patients who required removal of impacted mandibular third molars were recruited, and were randomised into two groups (50 in each). A standardised surgical technique was used for removal of the impacted teeth, and wounds were closed with sutures. Postoperatively, the study group was given Reso-Pac® dressing while the control group was not. Postoperative pain was measured using a visual analogue scale (VAS). Wound healing was assessed with the help of Landry’s scale, and we also measured thermal sensitivity. Data were analysed using the paired t test. The results in the study group were significantly better than those in the control group (p < 0.001). Reso-Pac® promoted wound healing and improved patients’ comfort during the postoperative phase.     

Enamel matrix derivative,inflammation and soft tissue wound healing

Over 15 years have now passed since enamel matrix derivative (EMD) emerged as an agent capable of periodontal regeneration. Following thorough investigation, evidenced‐based clinical application is now established for a multitude of clinical settings to promote regeneration of periodontal hard tissues. Despite the large number of studies and review articles written on this topic, no single review has compiled the influence of EMD on tissue inflammation, an area of research that merits substantial attention in periodontology. The aim of the present review was to gather all studies that deal with the effects of EMD on tissue inflammation with particular interest in the cellular mechanisms involved in inflammation and soft tissue wound healing/resolution. The effects of EMD on monocytes, macrophages, lymphocytes, neutrophils, fibroblasts and endothelial cells were investigated for changes in cell behavior as well as release of inflammatory markers, including interleukins, prostaglandins, tumor necrosis factor‐α, matrix metalloproteinases and members of the OPG‐RANKL pathway. In summary, studies listed in this review have reported that EMD is able to significantly decrease interleukin‐1b and RANKL expression, increase prostaglandin E₂ and OPG expression, increase proliferation and migration of T lymphocytes, induce monocyte differentiation, increase bacterial and tissue debris clearance, as well as increase fibroplasias and angiogenesis by inducing endothelial cell proliferation, migration and capillary‐like sprout formation. The outcomes from the present review article indicate that EMD is able to affect substantially the inflammatory and healing responses and lay the groundwork for future investigation in the field.     

An immunohistochemical study of matrix molecules associated with barrier membrane-mediated periodontal wound healing

Guided tissue regeneration (GTR) is a clinical procedure developed to facilitate periodontal regeneration by using barrier membranes to selectively promote the repopulation of a periodontal defect by periodontal ligament and bone cells at the expense of epithelial and gingival connective tissue cells. The aim of this study was to gain insight into the biological events occurring during membrane mediated periodontal wound healing by examining the immunohistochemical expression of a number of extracellular matrix components in tissues treated via the GTR technique. Experimental periodontal defects were created around the second premolar tooth in 4 dogs and wound closure was achieved by application of expanded polytetrafluoroethylene membranes around each tooth and flap positioning coronal to the cementoenamel junction. The dogs were sacrificed after a 4-wk healing period, block dissections of the part of the mandible containing the experimental tooth were obtained and paraffin sections were prepared. Using standard immunohistochemical techniques, the sections were stained with a monoclonal antibody against bone morphogenetic proteins 2 and 4 (BMP-2 and -4) and polyclonal antibodies against collagen I, collagen II, decorin, biglycan, bone sialoprotein, osteopontin and osteocalcin. Collagen I was predominantly localized within the regenerating bone, whereas collagen III staining was more abundant in the soft connective tissues of the defect. Decorin and biglycan staining was faint within the extracellular matrix of the regenerating defect, although both proteoglycans exhibited intense intracellular localization within some of the cells inhabiting the defect. The staining for BMP-2 and -4 was weak within the bone but strong within the extracellular matrix of the regenerating soft tissue. Osteopontin and bone sialoprotein were strongly localized in the regenerating bone and cementum found within the defect. Osteocalcin staining was present in both the regenerating and mature cementum and associated cementoblasts, and it was relatively weaker in the regenerating bone compared to the mature bone. The observed pattern of immunolocalization of the extracellular matrix macromolecules suggests that the heterogeneous cell population filling the GTR wound had created an environment that was conducive to periodontal regeneration.