Factors influencing Frey syndrome after parotidectomy with acellular dermal matrix

BACKGROUND Frey syndrome,also known as ototemporal nerve syndrome or gustatory sweating syndrome,is one of the most common complications of parotid gland surgery.This condition is characterized by abnormal sensations in the facial skin accompanied by episodes of flushing and sweating triggered by cognitive processes,visual stimuli,or eating.AIM To investigate the preventive effect of acellular dermal matrix(ADM)on Frey syndrome after parotid tumor resection and analyzed the effects of Frey syndrome across various surgical methods and other factors involved in parotid tumor resection.METHODS Retrospective data from 82 patients were analyzed to assess the correlation between sex,age,resection sample size,operation time,operation mode,ADM usage,and occurrence of postoperative Frey syndrome.RESULTS Among the 82 patients,the incidence of Frey syndrome was 56.1%.There were no significant differences in sex,age,or operation time between the two groups(P>0.05).However,there was a significant difference between ADM implantation and occurrence of Frey syndrome(P<0.05).ADM application could reduce the variation in the incidence of Frey syndrome across different operation modes.CONCLUSION ADM can effectively prevent Frey syndrome and delay its onset.

皮肤再生“星舰”:探索ADM在扩张技术中的应用突破与潜能

大面积皮肤缺损后的外观和功能同步重建仍是临床中未攻克的难题。皮肤扩张技术已广泛用于修复重建领域,但受限于较低的扩张效率、高发的并发症,以及尚未明确的作用机制,如今的皮肤扩张技术发展到了瓶颈阶段。为解决该问题,我们提出了脱细胞真皮基质辅助扩张的创新想法,并在临床上取得初步成效。脱细胞真皮基质能提供“生物友好”界面,均衡机械外力,作为活性支架可承载各类细胞,而其在皮肤扩张过程中的具体作用机制更值得深入的探究。脱细胞真皮基质作为扩张伴侣协同皮肤扩张,有望打破现有的扩张极限,进一步拓展皮肤扩张的潜能。

Randomized controlled trial of minimally invasive surgery using acellular dermal matrix for complex anorectal fistula

AIM: To compare the efficacy and safety of acellular dermal matrix (ADM) bioprosthetic material and endorectal advancement flap (ERAF) in treatment of complex anorectal fistula. METHODS: Ninety consecutive patients with complex anorectal fistulae admitted to Anorectal Surgical Department of First Affi liated Hospital, Xinjiang Medical University from March 2008 to July 2009, were enrolled in this study. Complex anorectal fistula was diagnosed following its clinical, radiographic, or endoscopic diagnostic criteria. Under spinal anesthesia, patients underwent identification and irrigation of the fistula tracts using hydrogen peroxide. ADM was securely sutured at the secondary opening to the primary opening using absorbable suture. Outcomes of ADM and ERAF closure werecompared in terms of success rate, fecal incontinence rate, anorectal deformity rate, postoperative pain time, closure time and life quality score. Success was defined as closure of all external openings, absence of drainage without further intervention, and absence of abscess formation. Follow-up examination was performed 2 d, 2, 4, 6, 12 wk, and 5 mo after surgery, respectively. RESULTS: No patient was lost to follow-up. The overall success rate was 82.22% (37/45) 5.7 mo after surgery. ADM dislodgement occured in 5 patients (11.11%), abscess formation was found in 1 patient, and fistula recurred in 2 patients. Of the 13 patients with recurrent fistula using ERAF, 5 (11.11%) received surgical drainage because of abscess formation. The success rate, postoperative pain time and closure time of ADM were significantly higher than those of ERAF (P < 0.05). However, no difference was observed in fecal incontinence rate and anorectal deformity rate after treatment with ADM and ERAF. CONCLUSION: Closure of fistula tract opening with ADM is an effective procedure for complex anorectal fistula. ADM should be considered a first line treatment for patients with complex anorectal fistula.

A novel porcine acellular dermal matrix scaffold used in periodontal regeneration

Regeneration of periodontal tissue is the most promising method for restoring periodontal structures.To find a suitable bioactive three- dimensional scaffold promoting cell proliferation and differentiation is critical in periodontal tissue engineering.The objective of this study was to evaluate the biocompatibility of a novel porcine acellular dermal matrix as periodontal tissue scaffolds both in vitro and in vivo.The scaffolds in this study were purified porcine acellular dermal matrix(PADM) and hydroxyapatite-treated PADM(HA-PADM). The biodegradation patterns of the scaffolds were evaluated in vitro.The biocompatibility of the scaffolds in vivo was assessed by implanting them into the sacrospinal muscle of 20 New Zealand white rabbits.The hPDL cells were cultured with PADM or HA-PADM scaffolds for 3,7,14,21 and 28 days.Cell viability assay,scanning electron microscopy(SEM),hematoxylin and eosin(H&E) staining, immunohistochemistry and confocal microscopy were used to evaluate the biocompatibility of the scaffolds.In vitro,both PADM and HA-PADM scaffolds displayed appropriate biodegradation pattern,and also,demonstrated favorable tissue compatibility without tissue necrosis,fibrosis and other abnormal response.The absorbance readings of the WST-1 assay were increased with the time course, suggesting the cell proliferation in the scaffolds.The hPDL cells attaching,spreading and morphology on the surface of the scaffold were visualized by SEM,H&E staining,immnuohjstochemistry and confocal microscopy,demonstrated that hPDL cells were able to grow into the HA-PADM scaffolds and the amount of cells were growing up in the course of time.This study proved that HA-PADM scaffold had good biocompatibility in animals in vivo and appropriate biodegrading characteristics in vitro.The hPDL cells were able to proliferate and migrate into the scaffold.These observations may suggest that HA-PADM scaffold is a potential cell carrier for periodontal tissue regeneration.

Reconstruction of the abdominal wall by using a combination of the human acellular dermal matrix implant and an interpositional omentum flap after extensive tumor resection in patients with abdominal wall neoplasm: A preliminary result

AIM： To present our trial using a combination of the human acellular dermal matrix （HADM） implant and an interpositional omentum flap to repair giant abdominal wall defects after extensive tumor resection. METHODS： Between February and October of 2007, three patients with giant defects of the abdominal wall after extensive tumor resection underwent reconstruction with a combination of HADN and omentum flap. Postoperative morbidities and signs of herniation were monitored. RESULTS： The abdominal wall reconstruction was successful in these three patients, there was no severe morbidity and no signs of herniation in the follow-up period. CONCLUSION： The combination of HADM and omentum flap offers a new, safe and effective alternative to traditional forms in the repair of giant abdominal wall defects. Further analysis of the long-term outcome and more cases are needed to assess the reliability of this technique.

Differentiation of mesenchymal stem cells into neuronal cells on fetal bovine acellular dermal matrix as a tissue engineered nerve scaffold

The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells fol-lowing induction with neural differentiation medium. We performed long-term, continuous observation of cell morphology, growth, differentiation, and neuronal development using several microscopy techniques in conjunction with immunohistochemistry. We examined speciifc neu-ronal proteins and Nissl bodies involved in the differentiation process in order to determine the neuronal differentiation of bone marrow mesenchymal stem cells. The results show that bone marrow mesenchymal stem cells that differentiate on fetal bovine acellular dermal matrix display neuronal morphology with unipolar and bi/multipolar neurite elongations that express neuro-nal-speciifc proteins, includingβIII tubulin. The bone marrow mesenchymal stem cells grown on fetal bovine acellular dermal matrix and induced for long periods of time with neural differen-tiation medium differentiated into a multilayered neural network-like structure with long nerve ifbers that was composed of several parallel microifbers and neuronal cells, forming a complete neural circuit with dendrite-dendrite to axon-dendrite to dendrite-axon synapses. In addition, growth cones with filopodia were observed using scanning electron microscopy. Paraffin sec-tioning showed differentiated bone marrow mesenchymal stem cells with the typical features of neuronal phenotype, such as a large, round nucleus and a cytoplasm full of Nissl bodies. The data suggest that the biological scaffold fetal bovine acellular dermal matrix is capable of supporting human bone marrow mesenchymal stem cell differentiation into functional neurons and the subsequent formation of tissue engineered nerve.

The Versatility of Acellular Fetal Bovine Dermal Matrix for Head and Neck Surgical Reconstruction in Children

Objectives: To describe the versatility of acellular fetal bovine dermal matrix as an alternative to human cadaveric allograft for head and neck reconstructive procedures in children. Study Design: Case series with chart review. Methods: A database of pediatric operative procedures was queried for the use of acellular fetal bovine dermal matrix over a 16-month period. Indications for reconstruction were assessed and initial parental and surgeon satisfaction with the product were noted. Results: During the time period of 3/2012 and 7/2013 a total of 8 reconstructive procedures were performed on pediatric patients using acellular fetal bovine dermal matrix. Indications for use varied and included open and transnasal endoscopic repair of encephaloceles and soft tissue reconstructions including lateral pharyngeal wall repair, cleft palate repair, and facial recontouring operations. Acellular fetal bovine dermal matrix had a subjectively increased ease of use as compared to the surgeon’s prior experience with human cadaveric acellular dermis. Every parent vocalized a greater comfort level with the use of a bovine product over the alternative of human cadaveric tissue. The cost of acellular fetal bovine dermal matrix is slightly lower than the cost of human cadaveric acellular dermis. Conclusions: Acellular fetal bovine dermal matrix appears to be an acceptable alternative to human cadaveric acellular dermis for various forms of head and neck soft tissue reconstruction in children. Further prospective studies are warranted to assess for any differences in the long-term efficacy of this product as compared to other forms of allograft reconstruction.

Application of acellular dermal matrix for intestinal elongation in animal models

AIM:To investigate the eff icacy of acellular dermal matrix(ADM) for intestinal elongation in animal models.METHODS:Japanese white big-ear rabbits(n = 9) and Wuzhishan miniature pigs(n = 5) were used in the study.Home-made and commercial ADM materials were used as grafts,respectively.A 3-cm long graft was interposed in continuity with the small bowel and a sideto-side anastomosis,distal to the graft about 3-4 cm,was performed.The animals were sacrificed at 2 wk,4 wk,8 wk and 3 mo after surgery and the histological changes were evaluated under light microscope and electron microscope.RESULTS:The animals survived after the operation with no evidence of peritonitis and sepsis.Severe ad-hesions were found between the graft and surrounding intestine.The grafts were completely absorbed within postoper ative two or three months except one.Histological observ ation showed inflammation in the grafts with fibrinoid necroses,infiltration of a large amount of neutrophils and leukomonocytes,and the degree varied in different stages.The neointestine with wellformed structures was not observed in the study.CONCLUSION:It is not suitable to use acellular dermal matrix alone as a scaffold for the intestinal elongation in animal models.

Optimal Bioprinting Parameters and Experimental Investigation of Acellular Dermal Matrix Scaffold

Acellular dermal matrix(ADM)as a biomaterial is currently believed to be promising tissue repair improvement.With the development of tissue engineering,ADM is increasingly used as biological scaffolds.We explored the feasibility and performance of ADM biological scaffolds that fabricated by 3D printing.This paper presented our study on the printability of 3D printed ADM scaffolds,with a focus on identifying the influence of printing parameters/conditions on printability.To characterize the printability,we examined the fiber morphology,pore size,strand diameter,and mechanical property of the printed scaffolds.Our results revealed that the printability could be affected by a number of factors and among them,the most considerable one was related to the nozzle diameter and the composition of ADM.We then evaluated the biocompatibility in terms of cytotoxicity,cell proliferation and vivisection.In vitro evaluation of the ADM scaffolds was carried out and the experimental results indicated that cells were viable and proliferative during the period of study.In vivo results also indicated that the defect area was well repaired without any noticeable infection,hematoma and other conditions.In conclusion,ADM could be reconstructed with 3D printing technology and ADM biological scaffold has potential applications for tissue engineering.

Treatment of oral lichen planus by surgical excision and acellular dermal matrix grafting:Eleven case reports and review of literature

BACKGROUND Oral lichen planus(OLP)is a chronic inflammatory disorder,and it can affect normal oral function.The conventional treatments for OLP are not always effective,and relapse easily occurs.Therefore,treatment of OLP is difficult and challenging.In this study,we evaluated over a long period the clinical efficacy of surgical excision and acellular dermal matrix(ADM)grafting in patients with refractory OLP.CASE SUMMARY Eleven patients with refractory OLP underwent a standardized protocol of surgical excision and ADM grafting.The condition of the area of the grafted wound,the intraoperative maximum mouth opening,pain,and clinical healing were assessed at postoperative follow-up visits.All patients had a flat surgical area with similar mucosal tissue coverage and local scar formation.Patients had no irritation and pain in their mucous membranes when eating acidic and spicy food.All patients’mouth openings returned to normal within 2-6 mo after surgery.During follow-up,none of the patients had recurrence of OLP after surgery.The longest follow-up was 11 yr and the shortest was 6 mo,and none of the patients relapsed during follow-up.CONCLUSION Surgical excision and ADM grafting could be an effective method to treat refractory OLP.

Effects of allogeneic mouse adipose-derived mesenchymal stem cell-microporous sheep acellular dermal matrix on healing of wound with full-thickness skin defect in mouse and the related mechanism

Objective:To explore the effects of allogeneic mouse adipose-derived mesenchymal stem cell(ADSC)-microporous sheep acellular dermal matrix(ADM)on wound healing of full-thickness skin defect in mice and the related mechanism.Methods:One Kunming mouse was sacrificed by cervical dislocation to collect adipose tissue from the inguinal region.Mouse ADSCs were isolated from the adipose tissue and cultured in vitro.Cells in the third passage were identified by cell adipogenic and osteogenic differentiation.The expressions of CD34,CD73,CD90,and CD105 were analyzed by flow cytometer.After one sheep was sacrificed with the skin of its back cut off,microporous sheep ADM was prepared by using acellular processing and freeze-thaw method.A round and full-thickness skin defect wound,with a diameter of 12 mm,was made on the back of each of 36 Kunming mice.The wounds were covered by microporous sheep ADM.The mice were divided into ADSC group and control group with 18 mice in each group according to the random number table method after surgery.A volume of 0.2 ml of DMEM/F12 culture medium containing 1×10^(6)ADSCs was injected between microporous sheep ADM and the wound of each mouse in ADSC group,while 0.2 ml of DMEM/F12 culture medium was injected between microporous sheep ADM and the wound of each mouse in control group.At post-surgery day(PSD)12 and 17,the wound healing rate in each group was calculated respectively;wound vascularization in 2 groups of mice was observed under the reverse irradiation of back light;and the granulation tissue in the wound in ADSC group was observed by means of hematoxylin-eosin staining.At PSD 7,the thickness of the granulation tissue in the wound was measured in each group of mice.At PSD 12 and 17,the immunohistochemical method was used to detect the expression of VEGF in each group of mice.The number of samples was 6 in each group at each time point in the above experiments.The data obtained were processed with t-test and factorial design ANOVA.Results:(1)After 7 days of adipogenic induction,red lipid droplets were observed in the cytoplasm with oil red O staining.After 21 days of osteogenic induction,black calcium deposition was observed in the medium stained with silver nitrate.The expression levels of CD73,CD90,CD 105 and CD34 in cells were 97.82%,99.32%,97.35%and 5.88%respectively.The cells were identified as ADSCs.(2)The wound healing rates of ADSC group at PSD 12 and 17[(78±6)%,(98±3)%]were significantly higher than those of control group at PSD 12 and 17[(60±9)%,(90±4)%,t=4.26,4.46,p<.01].(3)At PSD 7,no vessels obviously grew into the center of the wound in both groups of mice,while the granulation tissue already covered the wound in ADSC group.At PSD 12,the wound in ADSC group was more well-perfused than control group.At PSD 17,it was observed that large vessels were crossing through the whole wound in ADSC group,while large vessels were observed without crossing through the whole wound in control group.(4)In ADSC group,at PSD 7,the wound was covered with thin granulation tissue,and the granulation tissue was obviously thickened at PSD 12.At PSD 17,the granulation tissue was covered by epidermis.At PSD 7,the thickness of the granulation tissue in the wound in ADSC group[(0.62±0.05)mm]was significantly greater than that in control group[(0.31±0.04)mm,t=12.27,p<.01].(5)At PSD 12 and 17,the expression levels of VEGF in the wound in ADSC group[(80.7±2.2),(102.8±2.6)/mm^(2)]were significantly than those in control group[(59.5±2.4),(81.5±2.6)/mm^(2),t=15.95,14.14,p<.01].Conclusions:Allogeneic mouse ADSC-microporous sheep ADM can promote angiogenesis and the growth of granulation tissue in the wound with full-thickness skin defect in mice,thus accelerating wound healing.The mechanism is probably related with the increase in the expression of VEGF.

Histologic analysis and long-term effect of acellular dermal matrix combined with autologous thin split-thickness skin graft

Objective To evaluate the long-term therapeutic effect and histologic result of ADM combined with autologous thin split-thickness skin graft.Methods 23 patients were treated with acellalar dermal matrix(ADM) combined with autoiogous

Enhancing cartilage regeneration and repair through bioactive and biomechanical modification of 3D acellular dermal matrix

Acellular dermal matrix(ADM)shows promise for cartilage regeneration and repair.However,an effective decellularization technique that removes cellular components while preserving the extracellular matrix,the transformation of 2D-ADM into a suitable 3D scaffold with porosity and the enhancement of bioactive and biomechanical properties in the 3D-ADM scaffold are yet to be fully addressed.In this study,we present an innovative decellularization method involving 0.125%trypsin and 0.5%SDS and a 1%Triton X-100 solution for preparing ADM and converting 2D-ADM into 3D-ADM scaffolds.These scaffolds exhibit favorable physicochemical properties,exceptional biocompatibility and significant potential for driving cartilage regeneration in vitro and in vivo.To further enhance the cartilage regeneration potential of 3D-ADM scaffolds.we incorporated porcine-derived small intestinal submucosa(SIS)for bioactivity and calcium sulfate hemihydrate(CSH)for biomechanical reinforcement.The resulting 3D-ADM+SIS scaffolds displayed heightened biological activity,while the 3D-ADM+CSH scaffolds notably bolstered biomechanical strength.Both scaffold types showed promise for cartilage regeneration and repair in vitro and in vivo,with considerable improvements observed in repairing cartilage defects within a rabbit articular cartilage model.In summary,this research introduces a versatile 3D-ADM scaffold with customizable bioactive and biomechanical properties,poised to revolutionize the field of cartilageregeneration.

Lessons Learned from Three Different Acellular Dermal Matrices in Direct-to-Implant Breast Reconstruction

The aim of the study was to show significant differences regarding postoperative complications and outcomes using three different Acellular Dermal Matrices (ADM), namely Epiflex®, Strattice® and Braxon®, in immediate implant-based subpectoral breast reconstruction cases. Background: The use of Acellular Dermal Matrices for implant-based breast reconstruction cases continues to evolve. There is a wide variety of products which differ significantly in their biological features. It remains unclear if and how these differences manifest in clinical practice. Methods: 82 cases of primary breast reconstruction in the Department of Plastic and Aesthetic Surgery of HELIOS Clinics Schwerin, Germany between 2010 and 2018 were analyzed. 25 patients received Strattice® acellular dermal matrix (SADM), 22 cases Epiflex® acellular dermal matrix (EADM) and the remaining 35 cases Braxon® acellular dermal matrix (BADM). The mean follow-up was 1.8 years. Cases were analyzed regarding minor or major complications and rate of capsular contracture grade III or IV (Baker Classification). Results: The overall complication rate was 34.1% for all groups (SADM = 40%, EADM = 50%, BADM = 20%, p-value = 0.051). Of all cases, 6 patients underwent implant exchange or secondary autologous reconstruction due to capsular contracture (7.3%). The mean time between revision due to capsular contracture and reconstruction was 35.8 ± 14.4 months. 50% of patients, who developed capsular contracture, received postoperative radiation. Mean hospitalization time was 8.2 ± 3 days (SADM = 8 ± 3.2 days, EADM = 10 ± 2.8 days, BADM = 6 ± 1.3 days). There were no significant differences between all three groups for demographics, overall complication rate or capsular contracture. However, patients receiving Braxon® matrix showed significantly fewer minor complications (p-value = 0.01). Moreover, patients receiving Braxon® ADM showed a significantly lower time of hospitalization (p < 0.001). Conclusion: No significant differences regarding the overall complication rate were found between the three groups. Different biological features of ADM showed a weak influence on overall results. However, patients receiving Braxon® ADM showed significantly lower minor complication rates and hospitalization time. In addition, these matrices showed a trend towards lower capsular contracture rates. The low rate of capsular contracture hints at possible advantages of ADM-use in direct-to-implant cases.

Macrophage phenotypes correspond with remodeling outcomes of various acellular dermal matrices

Macrophages have recently been characterized as having an M1 or M2 phenotype based on receptor expression, mechanism of activation and function. The effects of macrophage phenotype upon tissue remodeling following implantation of an acellular dermal matrix (ADM) is largely unknown. The purpose of this study was to compare the macrophage phenotype and tissue remodeling elicited by four different ADMs (DermaMatrix, AlloDerm, Integra and Der mACELL). ADM samples were wrapped around the inferior epigastric vessels of a rat and were harvested on 7, 14, 21 and 42 days post implantation. Immunohistologic methods were used to identify macrophage surface markers CD68 (pan macrophage), CCR7 (M1 profile), and CD206 (M2 profile). All human derived ADMs showed a bell shaped curve for distribution of CD68+ macrophages with peaks for DermaMatrix occurring at day 14 and peak influx for AlloDerm occurring on day 21. In contrast, bovine derived Integra showed an increasing trend of macrophages with time. DermACELL had the highest influx of macro- phages while Integra had the lowest. A quantitative analysis of phenotype of macrophages in AlloDerm showed that the cells were predominantly M1 at 7, 14, 21 and 42 days post implantation. In contrast, Integra showed a mixed M1/M2 population of macrophages at all time points. The histopathologic evaluation showed that a predominantly M1 macrophage response was associated with a more inflamematory type tissue remodeling outcome in AlloDerm while a mixed M1/M2 macrophage response was associated with a more constructive tissue remodeling response seen in the other substrates.

脱细胞真皮基质和带蒂颊脂垫瓣修复颊部软组织缺损的对比研究

目的比较脱细胞真皮基质(ADM)和带蒂颊脂垫瓣(PBFPF)修复颊部软组织缺损的效果。方法选取我院84例行颊黏膜缺损修复的患者,随机分为ADM组和PBFPF组,每组42例。ADM组患者采用ADM修复,PBFPF组患者使用PBFPF修复。比较2组患者修复时间、经口进食时间、住院时间。于术前、术后1周、术后1个月、术后6个月测量并比较患者的最大开口度,记录患者的修复有效率及并发症发生情况。观察患者术后口腔颌面部功能(吞咽功能、语言功能、咀嚼功能)改善情况。结果2组患者修复时间、经口进食时间、住院时间、并发症总发生率、术后吞咽功能、术后语言功能比较,差异均无统计学意义(P>0.05)。ADM组与PBFPF组患者最大开口度组间比较、组间与时点的交互效应差异无统计学意义(P>0.05),时点的比较差异有统计学意义(P<0.05)。PBFPF组中缺损面积为>13~20 cm2的患者修复有效率高于ADM组(P<0.05)。PBFPF组患者的咀嚼功能优于ADM组(P<0.05)。结论PBFPF及ADM用于口腔黏膜组织缺损的修复各有优势,对于黏膜缺损面积较大(>13~20 cm2)的患者,PBFPF的修复效果更好。

复合皮移植联合VSD修复碾压伤致肘关节外露

目的:探讨复合皮移植联合负压封闭引流(Vacuum sealing drainage,VSD)在碾压伤伴关节外露创面修复中的临床应用效果及可行性。方法:2020年12月,笔者科室收治1例因左上肢车祸伤致皮肤坏死伴肿胀1 d的患者,入院时查体左上肢肿胀,左前臂、肘部可见约15.0 cm×20.0 cm皮肤坏死,左手感觉功能减退,桡动脉尚可触及,急诊手术探查见肘关节外露、脱位,肱三头肌自肱骨大范围撕脱,尺神经外露、移位,肘关节、尺骨外露范围约3.0 cm×5.0 cm。根据患者病史、临床表现、左上肢X线片及手术探查体征诊断左上肢碾压伤,肘关节外露。应用复合皮移植两步法联合VSD覆盖创面,自体中厚皮片移植修复皮肤缺损。结果:患者左上肢皮肤缺损处愈合良好,术后4个月复查,肘关节屈曲、伸直、旋转功能均恢复良好。结论:对于此例肘关节、骨外露创面,应用复合皮移植后可覆盖骨外露创面,大大降低了手术难度及患者的痛苦,为以后相对小面积骨外露创面的修复提供了新思路。

环氧化合物和碳化二亚胺交联pADM的性能比较

采用丙三醇缩水甘油醚(GPE)和碳化二亚胺(EDC)对脱细胞真皮基质(pADM)分别进行交联改性,通过对交联后材料EC(GPE)-pADM、EDC-pADM的交联效率、XPS分析、KM鼠经口急毒、浸提液细胞毒性的表征和比较,探寻改性方法与材料性能之间的基本关系。研究结果表明,EDC比EC具有更高的交联效率;EC-pADM的亲水性能比EDC-pADM更好;EDC-pADM浸提液对KM鼠表现出一定经口毒性,而EC-pADM的毒性相对较低;两者浸出液细胞毒性检测均合格。综合而言,EC-pADM的性能优于EDC-pADM。

不同软组织替代物在比格犬尖牙唇侧区域移植后附着龈的厚度和组织学变化

背景:上皮下结缔组织移植被认为是软组织增量术的金标准,然而,自体移植需要开辟第二术区,延长手术时间,增加患者的疼痛感,这也使得软组织替代物成为研究热点。目的:比较不同软组织替代物在比格犬尖牙唇侧区域移植后移植区附着龈厚度和组织学变化。方法:在3只比格犬尖牙唇侧附着龈区域,分别用双层同种异体脱细胞真皮基质膜(allograft acellular dermal matrix,AADM)、牛源性脱细胞真皮基质(bovine acellular dermal matrix,BADM)联合浓缩生长因子膜以及BADM联合胶原蛋白海绵进行附着龈增厚。分别在术前和术后1,2,3,4个月测量附着龈厚度,术后4个月进行组织学观察。结果与结论:①术后第1-4个月,双层AADM组附着龈厚度及附着龈厚度增量均值高于其他2组(均P<0.05);②术后1个月3组附着龈厚度显著增加,而后呈下降趋势;术后3个月,BADM联合胶原蛋白海绵组与BADM联合浓缩生长因子组移植区附着龈厚度变化较术前差异无显著性意义(P>0.05);术后4个月,双层AADM组附着龈厚度均值较术前仍显著增加(P<0.05);第1-4个月双层AADM组附着龈厚度值最高,其次为BADM联合胶原蛋白海绵组,BADM联合浓缩生长因子组最低;③双层AADM组真皮基质与宿主牙龈组织良好的结合在一起,并可见新生纤维结缔组织和成纤维细胞长入基质内,另外两组移植物已经完全吸收,增量区域改建成与周围宿主组织一致的结构;④结果说明,AADM在牙龈增厚方面优于BADM联合浓缩生长因子膜和BADM联合胶原蛋白海绵。

钛镍记忆合金牵张器结合ADM增高犬牙槽嵴的动态观察

目的:观察牵张后犬下颌牙槽嵴高度的动态变化,探讨钛镍记忆合金牵张器结合脱细胞真皮基质(acellular dermal matrix,ADM)增高牙槽嵴后对牙槽嵴增高高度的影响。方法:健康成年雄性杂种犬12只牙槽嵴萎缩模型建成后,一侧行牵张手术,放入ADM及两个直径1.0mm、复形温度为33℃的"S"形牵张器;另一侧为对照侧,仅放入同样牵张器行牵张术,不放入ADM。术后1周、1个月、3个月拍摄X线片并分别测量下颌两侧牙槽嵴高度。结果:术后即刻实验侧和对照侧牙槽嵴增高高度无显著统计学差异。术后1、3个月对照侧牙槽嵴增高高度均高于实验侧。结论:ADM作为屏障膜,减缓牵张速度,延长牵张时间,在镍钛记忆合金牵张成骨过程中,是一种理想的引导骨组织再生(GBR)引导膜。