Pre-Treat Xenogenic Collagenous Blocks of Bone Substitutes with Saline Facilitate Their Manipulation and Guarantee High Bone Regeneration Rates, Qualitatively and Quantitatively.

Deproteinized bovine bone mineral particles embedded in collagen (DBBM-C) are widely used for bone regenerations with excellent, albeit sometimes variable clinical outcomes. Clinicians usually prepare DBBM-C by mixing with blood. Replacing blood by saline represents an alternative. We investigated if saline treatment could improve DBBM-C i. handling in vitro and ii. biological performances in a rabbit calvarial model. In vitro, DBBM-C blocks soaked in saline or blood were submitted to compression tests. In vivo, four poly ether ether ketone (PEEK)cylinders were placed on 16 rabbit skulls, filled with DBBM-C soaked in blood or saline for 2-4-8-12 weeks before histomorphometry. DBBM-C blocks were fully hydrated after 30 s in saline when 120 s in blood could not hydrate blocks core. Stiffness gradually decreased 2.5-fold after blood soaking whereas a six-fold decrease was measured after 30 s in saline. In vivo, saline treatment allowed 50% more bone regeneration during the first month when compared to blood soaking. This difference was then no longer visible. New bone morphology and maturity were equivalent in both conditions. DBBM-C saline-soaking facilitated its handling and accelerated bone regeneration of highly qualitative tissues when compared to blood treatment. Saline pretreatment thus may increase the clinical predictability of bone augmentation procedures.

A study on the immunohistochemical expression of napsin A in oral squamous cell carcinomas, intraepithelial neoplasia, and normal oral mucosa.

Napsin A is an aspartic proteinase expressed in some types of carcinomas, such as lung adenocarcinomas and renal cell carcinomas but rarely in squamous cell carcinomas. No specific studies have been carried out focusing on napsin A antibody expression in oral squamous cell carcinomas (OSCC). The aim of this study was to investigate the reactivity of this antibody in primary OSCC. This retrospective study included 70 OSCC cases of which 31 (44.3%) presented metastasis involvement. Patient data, including age, gender, tumor location, histological grade, regional and distant metastasis, were collected. OSCC edge epithelium with intraepithelial neoplasia and healthy oral mucosa (n = 10) were included in the analysis. Sections of lung adenocarcinomas (n = 2) were used as the positive control and an immunohistochemical assay for napsin A was performed on all cases. Napsin A expression was negative in all 70 cases of OSCC, as well as in the intraepithelial neoplasia adjacent to the carcinoma area and in healthy oral mucosa epithelium. Metastatic neck lymph nodes and distant organs were also negative for napsin A. This study shows that napsin A is consistently not expressed in oral squamous cell carcinoma, or in metastatic sites of primary OSCC, intraepithelial neoplasia, and healthy oral mucosa.

HSP105 expression in oral squamous cell carcinoma: Correlation with clinicopathological features and outcomes.

BACKGROUND: Heat shock proteins (HSPs) are released in response to stress situations, such as heat, inflammation, and infection. They are also involved in the tumor cell proliferation and prevention of apoptosis. Heat shock protein 105 (Hsp105/110) is a high-molecular-weight protein, which has been reported in many cancer types but few studies have been carried out on oral squamous cell carcinoma (OSCC). In the current study, we have focused on HSP105 expression on OSCC and evaluated their correlation with tumor clinicopathological parameters and patients' survival. METHODS: A retrospective study included 70 patients with OSCC of which 50 patients (71.4%) were male and 20 (28.6%) were female. The patient's information, including age, location, TNM stage, histological grade, regional metastasis, recurrence, and survival, were collected. Immunohistochemical staining for HSP105 was performed. The healthy oral mucosa (n = 10) was used as a control. The staining intensity and percentage of stained cells were semi-quantitatively evaluated, and HSP105 expression was correlated with tumor clinicopathological features and patient survival. RESULTS: Statistical analysis for HSP105 showed that there was no significant correlation with tumor clinicopathological features. However, HSP105 overexpression was associated with a decrease in the duration of patients' survival (P = .042). CONCLUSION: This result suggests that the increased expression of the HSP105 in the OSCC could be a prognostic factor for malignancy.

Calvarial Model of Bone Augmentation in Rabbit for Assessment of Bone Growth and Neovascularization in Bone Substitution Materials.

The basic principle of the rabbit calvarial model is to grow new bone tissue vertically on top of the cortical part of the skull. This model allows assessment of bone substitution materials for oral and craniofacial bone regeneration in terms of bone growth and neovascularization support. Once animals are anesthetized and ventilated (endotracheal intubation), four cylinders made of polyether ether ketone (PEEK) are screwed onto the skull, on both sides of the median and coronal sutures. Five intramedullary holes are drilled within the bone area delimited by each cylinder, allowing influx of bone marrow cells. The material samples are placed into the cylinders which are then closed. Finally, the surgical site is sutured, and animals are awaken. Bone growth may be assessed on live animals by using microtomography. Once animals are euthanized, bone growth and neovascularization may be evaluated by using microtomography, immune-histology and immunofluorescence. As the evaluation of a material requires maximum standardization and calibration, the calvarial model appears ideal. Access is very easy, calibration and standardization are facilitated by the use of defined cylinders and four samples may be assessed simultaneously. Furthermore, live tomography may be used and ultimately a large decrease in animals to be euthanized may be anticipated.

Modulation of MCP-1, TGF-ß1, and α-SMA Expressions in Granulation Tissue of Cutaneous Wounds Treated with Local Vitamin B Complex: An Experimental Study.

Vitamin B complex can modulate the inflammatory response and activate wound healing. However, the action mechanisms involved in this process are still unclear. The aim of this study was to evaluate the effects of vitamin B complex on the modulation of monocyte chemotactic protein (MCP)-1, transforming growth factor (TGF)-ß1, and α-smooth muscle actin (α-SMA) in granulation tissue growth. Cutaneous ulcers on Wistar rats were topically treated with vitamin B complex. MCP-1, TGF-ß1, and α-SMA expressions were evaluated 24, 72, and 168 h after the treatment. Inflammatory cells were counted and collagen fibril staining was performed. After 24 h, more mononuclear cells (p ≤ 0.01) and a higher MCP-1 (p ≤ 0.05) and TGF-ß1 (p ≤ 0.01) expression were observed. After 72 h, the number of fibroblasts and mononuclear cells (p ≤ 0.05) was elevated. After 168 h, an increased number of fibroblasts, myofibroblasts, and blood vessels (p ≤ 0.01) as well as a strong intensity of collagen fibril staining were seen. At that point, the cells presented a higher TGF-ß1 expression (p ≤ 0.05), and the size of the ulcer area was decreased (p ≤ 0.01). We can conclude that vitamin B complex may stimulate a positive modulation of MCP-1, TGF-ß1, and α-SMA expressions in granulation tissue of cutaneous ulcers.

Alveolar ridge keratosis--a retrospective clinicopathological study.

BACKGROUND: Alveolar ridge keratosis (ARK) is a distinct, benign clinicopathological entity, characterized by a hyperkeratotic plaque or patch that occurs on the alveolar edentulous ridge or on the retromolar trigone, considered to be caused by chronic frictional trauma. The aim of this retrospective study is to present the clinicopathological features of 23 consecutive cases of ARK. MATERIAL AND METHODS: The 23 biopsy samples of ARK were selected and pathological features were revised (keratosis, acanthosis, surface architecture, and inflammation). Factors such as the patient's gender, age, anatomical location, tobacco and alcohol use were analyzed. RESULTS: Sixteen out of the 23 cases studied were men and 7 women with a mean age of 55.05 (age ranged from 17 to 88 years). Thirteen cases had a history of tobacco habit, amongst whom, 4 also presented alcohol consumption. All the cases presented only unilateral lesions. Nineteen cases involved the retromolar trigone while 4 cases involved edentulous alveolar ridges. When observed microscopically, the lesions were mainly characterized by moderate to important hyperorthokeratosis. Inflammation was scanty or absent. In four of the cases, the presence of melanin pigment in the superficial corium or in the cytoplasm of macrophages was detected. None of the cases showed any features of dysplasia. CONCLUSION: Our results reveal that ARK is a benign lesion. However, the high prevalence of smokers amongst the patients might suggest that some potentially malignant disorders such as tobacco associated leukoplakia may clinically mimic ARK.

New perspectives on the dynamic behaviour of oral lichen planus.

Lichen planus, a chronic inflammatory disease that affects the skin and mucous membranes, is one of the most frequent dermatological disorders of the oral cavity. The prevalence of oral lichen planus ranges from 0.2% to 4%. The triggering factors remain unknown. Oral lichen planus can be considered to be a chronic disease of long duration with a dynamic evolution and frequent changes in clinical appearance. Three successive active stages can be distinguished, without sharp limits between them: an initial stage; a protracted intermediate stage with alternate periods of variable activity and quiescence, which carries a progressively increasing risk of malignant transformation; and a late stage that often ends in a clinically little-known, inactive cicatricial post-lichen stage, which does not respond to steroid treatment but retains the same risk.