Evaluation of filling materials in membrane‐protected bone defects. A comparative histomorphometric study in the mandible of miniature pigs.

In recent years, bone grafts and bone substitutes have been increasingly utilized underneath barrier membranes to optimize the treatment outcome of bone reconstructive therapy for defects in the alveolar process. In the present study, 4 different filling materials were evaluated in bone defects of similar dimensions in the mandible of miniature pigs. Blood clots and autografts were used as controls. The defects were covered with barrier membranes and allowed to heal for 4, 12 or 24 weeks. Histologic examination demonstrated that bone repair progressed through a programmed sequence of maturation steps closely resembling the pattern of bone development and growth regardless of whether bone grafts or substitutes were present or not. Histomorphometric analysis showed that autologous bone grafts (autografts) had the best osteoconductive properties during the initial healing period, with 39% of newly formed bone inside the membrane-covered defects at 4 weeks of healing. In addition, 87% of the graft surfaces were already covered by bone at this time. Both values were significantly higher for autografts than for the 4 alternative bone fillers (P < or = 0.05). At 12 weeks, these differences were no longer apparent, with all 5 filling materials showing similar values. Among the tested bone substitutes, tricalcium phosphate (TCP) showed a significantly higher percentage of bone fill at 24 weeks of healing. It can be concluded that sites filled with autografts clearly demonstrated the best results underneath barrier membranes in the early phase of healing. As far as degradation and substitution are concerned, TCP showed the most promising results. This filler, however, needs to be tested further in a more demanding animal model. Less favorable results were obtained for coral-derived hydroxyapatite granules and for demineralized freeze-dried bone allografts.     

Autogenous soft tissue grafting for periodontal and peri-implant plastic surgical reconstruction

This state-of-the-art review presents the latest evidence and the current status of autogenous soft tissue grafting for soft tissue augmentation and recession coverage at teeth and dental implant sites. The indications and predictability of the free gingival graft and connective tissue graft (CTG) techniques are highlighted, together with their expected clinical and esthetic outcomes. CTGs can be harvested from the maxillary tuberosity or from palate with different approaches that can have an impact on graft quality and patient morbidity. The influence of CTGs on soft tissue thickness and keratinized tissue width are also discussed.     

自体骨移植在腰椎后路椎间融合中的临床疗效分析

目的探讨腰椎后路手术中应用自体椎板、棘突骨颗粒为植骨材料行椎间融合治疗特殊的腰椎间盘突出症、腰椎管狭窄症及腰椎滑脱症等腰椎退变性疾病的临床效果。方法特殊腰椎间盘突出症、腰椎管狭窄症及腰椎滑脱症并行后路腰椎融合术(PLIF和TLIF)患者184例,按椎间融合材料分为3组,A组61例,单纯自体骨组;B组64例,PEEK椎间融合器组;C组59例,异体骨垫组。平均随访18个月(12~60个月)。统计3组患者术前一般资料、手术时间、术中出血量、术后下床时间、住院天数、术后融合率以及术后椎间高度及融合节段角度的变化情况,按JOA评分标准评价功能恢复情况。结果 3组患者术前一般资料、术中出血量、手术时间、术后下床时间、住院时间、JOA评分、术后1年椎间隙高度及融合节段角度比较,差异均无统计学意义(P0.05);3组患者术后3个月.JOA评分较术前均显著提高(P0.05)。A组术后1年的融合效果高于C组(P0.05);B组术后融合器移位的并发症发生率较高。结论在后路椎间融合中纯自体棘突、椎板骨移植能起到和PEEK融合器和异体骨融合器一样的维持椎间隙高度的作用,不延长术后卧床时间,且具有经济效益。     

L’ingénierie cutanée pour le traitement des brûlures graves

Severe burned patients need definitive and efficient wound coverage. Outcome of massive burns has been improved by using cultured epithelial autografts (CEA). Despite fragility, percentages of success take, cost of treatment and long-term tendency to contracture, this surgical technique has been developed in few burn centres. First improvements were to combine CEA and dermis-like substitute. Cultured skin substitutes provide earlier skin closure and satisfying functional result. These methods have been used successfully in massive burns. Second improvement was to allow skin regeneration by using epidermal stem cells. Stem cells have capacity to differentiate into keratinocytes, to promote wound repair and to regenerate skin appendages. Human mesenchymal stem cells contribute to wound healing and were evaluated in cutaneous radiation syndrome. Skin regeneration and tissue engineering methods remain a complex challenge and offer the possibility of new treatment for injured and burned patients.     

Outcomes of sprayed cultured epithelial autografts for full-thickness wounds: a single-centre experience

Introduction

The lack of autograft donor sites with major burns provides the impetus to develop innovative solutions due to the difficulty of wound closure. Autograft donor sites are particularly limited in patients with burns involving over 50% total body surface area (TBSA). The introduction of cultured epithelial cell autografts offers a potential solution to assist in wound closure. The objective of this study was the assessment of clinical results after sprayed application of the cultured epithelial autograft (CEA, Keraheal™, Seoul, Korea, MCTT) suspension onto the wounds of extensively burned patients.

Materials and methods

This retrospective clinical audit of major burn patients (n = 16) describes the use of CEA which was combined with 6:1 meshed expansion grafts in those with the burn over 40% TBSA in our hospital between the period of August 2007 and January 2010. The burn patients included 12 males and 4 females with a mean age 41.5 and a burn area of 51.3 ± 3.1% TBSA (30–70%; median: 50.5%) and a mean third burn area of 32.5 ± 3.0% TBSA (median 34.0%).

Results

The take rates were 37.6%, 68.0% and 90.0% on average at 2, 4 and 8 weeks after treatment with the suspension, respectively, and the transplantation of the cultured cells was applied to full-thickness burns, with the coverage of a skin area of 497.5 cm² per 1 ml of the cultured cells. For clinical follow-up, 12 patients were observed for 21.5 months on average, with a maximum follow-up period of 39 months. Six patients were excluded from the surveillance because two died during hospitalisation and the other four were impossible to trace.

Conclusion

The use of a sprayed cultured epithelial cell autograft (Keraheal™) in treating a full-thickness skin wound in severely burned patients results in favourable quality of scars and also good potential to save lives by providing epidermal cover.     

酪氨酸酶在自体中厚移植皮片中的表达

目的:检测酪氨酸酶在人体自体中厚移植皮片中的表达,并与自身正常皮肤作对照,初步认识酪氨酸酶在自体移植皮片色素过度沉着中的作用。方法:利用免疫组化法检测人体自体中厚移植皮片与原供区及受区周围自体正常对照皮肤中酪氨酸酶的蛋白表达,并行统计学分析。结果:酪氨酸酶的表达定位于表皮基底部黑素细胞的细胞质,在大部分自体中厚移植皮片中呈强阳性表达,表达率为65.2%,与自体正常对照皮肤比较,差异有显著性意义(P<0.01);酪氨酸酶在受区与原供区周围正常对照皮肤中的表达差异无显著性意义(P>0.05)。结论:α黑素细胞刺激激素(αMSH)在自体中厚移植皮片中较自体正常对照皮肤中的表达显著增高,在自体移植皮片色素过度沉着中起重要的调控作用。     

Initial experience with cultured epithelial autografts in massively burnt patients

Background: Prognosis in patients with severe burns is improved by early debridement and coverage with skin. The limiting factor in these patients is the lack of unburnt skin for harvesting. Cultured epithelial autograft (CEA) sheets provide an alternative means of covering debrided skin. This is a report on an initial experience with using CEA sheets. Methods: The two patients in this study had their medical records examined retrospectively. Results: The effective take of the CEA sheets was zero in both patients. One of the patients died approximately 6 weeks after admission. Conclusions: Because of the poor graft take seen in the patients in the present study, the use of CEA sheets only as a form of temporary biological dressing is recommended.     

From skin allograft coverage to allograft–micrograft sandwich method: A retrospective review of severe burn patients who received conjunctive application of cultured epithelial autografts

A 12-year retrospective review of severe burn patients who received cultured epithelial autografts (CEA) at the Singapore General Hospital Burns Centre from January 2005 to December 2016 was carried out. During this period, two different surgical modalities were employed to manage these burn injuries. In the earlier period, following early excision of the burn wounds, exposed surfaces were covered with a combination of split thickness skin autografts (STSG) and allografts. Surfaces covered with skin allografts were subsequently debrided of the allo-epidermis in about 3 weeks later, exposing the allodermis with granulating tissues for grafting of CEA; a technique known as the Cuono’s method. In the later period, allograft–autologous micrograft sandwich technique was used to graft on the early excised burns with subsequent CEA grafting. The former and latter groups represented by STSG/C (n = 10) and M/CEA (n = 14) respectively, were compared in terms of clinical profiles, outcomes, allograft/CEA usage and total graft cost. No significant differences were found based on mean age and presence of inhalation burns between the two treatment methods However, percentage total body surface area (TBSA) and Revised Baux Score were significantly higher (p < 0.05) in the M/CEA group compared to the STSG/C group. Differences in clinical outcomes of mortality and length of hospital stay between the 2 groups were statistically insignificant. The average area amount of skin allografts used per patient in the M/CEA group was significantly lower compared to the STSG/C method group which contributed to lower total average cost of grafts used per % TBSA in the M/CEA method group. This might be attributed to the presence of micrografts which seemed to improve stabilization of the wound bed resulting in less operating procedures and improving CEA take. To conclude, the M/CEA method introduced was able to treat more severe burn patients at lower graft costs without compromising critical clinical outcomes significantly.