• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.31 no.2
• /
• pp.143-149
• /
• 2005

Objects : With the advancement of tissue engineering techniques, the effort to develop bioartificial mucosa have been actively delivered. The problem we met with this technique is the lack of mechanical strength between kerationocyte layer and dermal layer, where in the normal skin and mucosa, they are tightly bound with rete ridge structure. The purpose of this study is to understand the 2D and 3D structure of rete ridge of mucosa and skin paddle for rendering more biomimetic structure to the artificial mucosa. Materials and Methods : Oral mucosa and skin from the patients who received the oral surgery and maxillofacial reconstruction were harvested. The epidermis was separated from the dermis after treating with dispase for 12-16 hours. H&E staining was performed for 2D(dimensional) structure study and confocal LASER and SEM study were performed for 3D structure. Mean height(Sc) and arithmetic mean deviation(Sa) of all surface height were calculated. Results : The average height of rete ridge of skin flap was between $67.14{\mu}m$ and $194.55{\mu}m$. That of oral mucosa was between $146.26{\mu}m$ and $167.51{\mu}m$. Pressure bearing area and attached gingiva of oral mucosa showed deeper rete ridges. Conclusion : To obtain the adequate strength of artificially cultured keratinocyte skin and mucosa flap, it is necessary to imitate the original skin and mucosa structure, especially rete ridge. Through this study, 2D and 3D rete ridge structure of normal mucosa and skin was obtained. These results can be used as basis for substrate morphology for keratinocytes culture.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.31 no.2
• /
• pp.150-160
• /
• 2005

Background: For normalization of displaced anatomical structure by large cyst, two-step procedure (decompression and enucleation afterward) has been recommended. However, the histological transformation after cystotomy for decompression was shown frequently in secondary enucleation. Therefore, analyses about effects and histological changes after decompression have been necessary. Methods: 48 cases diagnosed as large odontogenic cyst in the jaw and treated by decompression and secondary enucleation were retrospectively analyzed in clinical, rediographical, and histological aspects. Results: In dentigerous cyst, decompression was much useful. Impacted permanent teeth were erupted and reduction rate was higher than that of odontogenic keratocyst (OKC) and apical periodontal cyst. In OKC, among the 29 cases, 11 cases showed no-keratosis, proliferation and rete-ridge elongation after decompression. 4 cases showed no-keratosis, only. 7 cases showed orthokeratosis and rete-ridge elongation and 6 cases showed reteridge elongation, only. 1 case had no change. And the recurrence rate for OKCs was 10.3%. For all odontogenic cysts in this study, dysplasia was not found in cystic lining after decompression. Conclusions: This study implied that decompression for large odontogenic cyst was useful treatment modality because it was conservative treatment and recurrence rate was low although long treatment period was required.

• Journal of Veterinary Clinics
• /
• v.30 no.5
• /
• pp.399-402
• /
• 2013

An 8-year-old, female, mixed Thoroughbred horse was presented for the evaluation of the left upper eyelid mass with ocular discharge during 4 months. After unilateral surgery, excised eyelid mass and left eye were submitted for diagnosis. Grossly, the removed mass was $6{\times}7{\times}2$ cm in size and dome shape with rough irregular surface. On the cut surface, mass was firm and yellowish white in color. Histopathologically, severely proliferated stratified squamous epithelia were heavily invaginated into dermis, and then formed rete ridge or numerous squamous islands. These neoplastic islands were composed of multiple layers of prickle cells with intercellular bridge and central laminated keratin pearls or necrotic cellular debris. Based on the above results, this case was diagnosed as squamous cell carcinoma in upper eyelid of horse.

• Korean Journal of Veterinary Research
• /
• v.56 no.1
• /
• pp.41-43
• /
• 2016

A dead dove was found on the road and submitted for diagnosis. The bird was severely emaciated, with deformation in its facial area. Grossly, white coalescing nodules were seen on the cut surface of the nasal cavity. Histopathologically, epithelial cells of the upper respiratory tract were markedly proliferated, with ballooning degeneration, down growth of the rete ridge, and large eosinophilic intracytoplasmic inclusion bodies. Parakeratotic hyperkeratosis and focal necrotic focus was present in the proliferative area. The facial bones showed partial bone resorption. Transmission electron microscopy revealed numerous viral particles in epithelial cells with dumbbell-shaped bodies, consistent with poxvirus.

• Journal of Pharmaceutical Investigation
• /
• v.40 no.1
• /
• pp.45-49
• /
• 2010

Unlike human, with some exceptions, animals do not heal with excessive scar. The lack of suitable animal model has hindered the development of effective scar therapy. We previously reported that partial thickness rabbit ear wound model resembles human wound heal process. This study was designed to prepare a hypertropic scar wound model which can be employed for testing anti-scar therapy. Four wounds were created down to the bare cartilage on the anterior side of each rabbit ear using 8-mm dermal biopsy punch and histology analysis at post operation day (POD) 5, 28 and 48 were performed. As the outcome of scar formation is largely determined by the early inflammatory response to the wounding and the degree and the duration of occlusion, cephalodin(50 mg/kg) was injected daily and medical occlusive dressings were applied. Five micro wound and scar sections were stained with hematoxylin and eosin for quantification of epidermal regeneration and scar hypertrophy. Sections were also stained using Masson's trichrome and Sirius red to evaluate collagen organization and rete ridge formation. Wound closure process was assessed to 7wks post wounding. Complete removal of the epidermis, dermis and perichondrial layer caused delayed epithelialization, which results in hypertropic scarring. The inability of the wounds to contract and the delay in epithelialization in rabbit ear was likely due to cartilage and it created scar elevation. The results suggest that full thickness surgical punch wound model in rabbit ear could be employed as a reliable and reproducible scar wound model for testing anti-scar therapy.

• Archives of Plastic Surgery
• /
• v.33 no.5
• /
• pp.601-605
• /
• 2006

Purpose: Large skin defect by various causes, should be covered by autologous skin graft. But, the donor site of autologous skin graft is limited and leaves permanent donor scar and contracture. There have been our trial to engineer artificial skin using allogenic dermis (AlloDerm) with basement membrane. Methods: Dermal and epidermal layer were separated by immersing in dipase solution for 30 minutes, and the separated layers were treated with 0.05% trypsin for 10 minutes. And then each layer was cultivated to fibroblasts and keratinocytes on a culture medium. Fibroblasts were first penetrated into basement membrane of allogenic dermis facing down, then allogenic dermis was flipped over to face up and keratinocytes were transplanted to allogenic dermis. Results: Observing artificial skin fabricated in vitro, we found following: 1) The artificial skin opened in air for 5 days formed epidermal layer. In dermal layer, fibroblast was distributed evenly among all. 2) The artificial skin opened in air for 30 days formed thicker and thicker, and it formed basement membrane, spinous and granular layers. PAS stain to confirm existence of basement membrane showed positive reaction. 3) Cytokeratin 10 stain to confirm the formation of epidermal layer showed positive reaction. 4) The formation of thick keratin, lamellar body and desmosome similar to human skin were observed in result of an electron micrograph. Conclusion: As a result of research, the structure seen in normal skin such as rete ridge, is found in reproduced artificial skin. This type of artificial skin can be used as a useful model for investigating skin disease and for clinical application also.

• Journal of Korean Dental Science
• /
• v.16 no.2
• /
• pp.172-181
• /
• 2023

Purpose: To investigate the effect of epidermal growth factor (EGF) with collagen matrix (CM) for increasing gingival thickness. Materials and Methods: In five mongrel dogs, bilateral gingival defects were surgically made on the maxillary canines. After two months, either a subepithelial connective tissue graft (group SCTG) or CM with EGF (0.1 ug/ml, group EGF) was grafted, and the flap was coronally positioned to cover the graft materials. The animals were sacrificed after three months. Intraoral scanning was performed for soft tissue analysis. Histologic and histomorphometric analyses were performed. Result: Two animals exhibited wound dehiscence during the healing phase, leaving three for analysis. No statistically significant difference was found in soft tissue changes (P>0.05). The level of gingival margin (GM) increased in both groups (1.02±0.74 mm in group SCTG vs. 1.24±0.83 mm in group EGF). Linear increases at the GM pre-augmentation in the soft tissue profile were 1.08±0.58 mm in group SCTG and 0.96±0.73 mm in group EGF. Histomorphometric parameters (keratinized tissue height, tissue thickness, and rete peg density) were not significantly different between the groups (P>0.05). Conclusion: EGF loaded onto CM led to comparable gingival phenotype enhancement to SCTG.

• Journal of Periodontal and Implant Science
• /
• v.53 no.6
• /
• pp.417-428
• /
• 2023

Purpose: To investigate the effect of xenogeneic collagen matrix (XCM) with polydeoxyribonucleotide (PDRN) for gingival phenotype modification compared to autogenous connective tissue graft. Methods: Five mongrel dogs were used in this study. Box-type gingival defects were surgically created bilaterally on the maxillary canines 8 weeks before gingival augmentation. A coronally positioned flap was performed with either a subepithelial connective tissue graft (SCTG) or XCM with PDRN (2.0 mg/mL). The animals were sacrificed after 12 weeks. Intraoral scanning was performed for soft tissue analysis, and histologic and histomorphometric analyses were performed. Results: One animal exhibited wound dehiscence, leaving 4 for analysis. Superimposition of STL files revealed no significant difference in the amount of gingival thickness increase (ranging from 0.69±0.25 mm to 0.80±0.31 mm in group SCTG and from 0.48±0.25 mm to 0.85±0.44 mm in group PDRN; P>0.05). Histomorphometric analysis showed no significant differences between the groups in supracrestal gingival tissue height, keratinized tissue height, tissue thickness, and rete peg density (P>0.05). Conclusions: XCM soaked with PDRN yielded comparable gingival augmentation to SCTG.