Oral mucosae types

HSV is divided into HSV-1, which causes oral, ocular, or facial infections, and HSV-2, which causes genital infection. However, either type can cause disease at either body site. HSV-1 causes painful vesicular lesions in the oral mucosa, face, or around the eyes. HSV-2 or genital herpes... 

Rat Groups of 50 male and 50 female Fischer 344/N rats, eight weeks of age, were administered skin applications of 0, 188 or 375 mg/kg bw 2,3-dibromo-l-propanol (98% pure) in 95% ethanol on five days per week for 48-51 weeks (males) or 52-55 weeks (females). The study was terminated at 48-51 weeks for males and 52-55 weeks for females because of reduced survival of the high-dose groups and because sentinel mice housed in the same room as the rats tested positive for lymphocytic choriomeningitis virus. As shown in Table 2, there w ere increased incidences of skin neoplasms (all types), squamous-cell carcinomas of the skin, basal-cell tumours [not further specified] of the skin, squamous-cell carcinomas of the oral mucosa, squamous-cell papillomas of the oesophagus, squamous-cell papillomas of the forestomach, adenocarcinomas of the... 

Human oral mucosa consists of different cell types including keratinized and non-keratinized striated epithelial, but the buccal mucosa is composed predominately of the latter. In selecting an appropriate animal model care was taken to ensure that the mucosal structure in the selected species matched that in man as closely as possible. Based on histological examinations all the rodent species (rat, guinea pig, hamster and rabbit) would constitute poor models because of extensive keratinization of their buccal mucosa. Of the other possibilities, the dog appeared to be the best choice. 

Oral mucosae are composed of multiple layers of cells, which show various patterns of differentiation dependent on the functions of different regions in the oral cavity. The oral mucosa is covered by a stratified, squamous epithelium, and three different types of mucosa can be distinguished the masticatory, the lining, and the specialized mucosa. Blood supply to the oral cavity tissues is delivered via the external carotid artery, which branches to the maxiliary lingual and facial artery. There are no mucus-secreting goblet cells in the oral mucosa, but mucins are found in human saliva. These mucins are water-soluble and form a gel of 10-200 pm thickness. Saliva, mainly composed of water (99%), is continuously secreted in the oral cavity and exists as a film with a thickness of 0.07-0.1 mm. ... 

Oral mucosa (buccal) cells have been used as one of the most easily obtainable exfoliated cell types from volunteer donors. The spectra collected from entire individual cells are used to introduce the possibiUty of using IR microspectral results to distinguish between ceU types and to determine their state of health. In particular, the heterogeneity of observed spectra-and methods to overcome such problems-are discussed. 

A 74-year-old woman, who was referred for evaluation of pain and persistently abnormal exposure of jaw bone after extraction of teeth, had been using weekly oral alendronate for osteoporosis for about 5 years. She had the clinical features of bisphosphonate-associated osteonecrosis of the mandible, which was precipitated by extraction of teeth 14 months before she was referred for assessment. She had multiple susceptibility factors for osteonecrosis of the jaw, including older age, type 2 diabetes mellitus, and a long duration of bisphosphonate therapy. The mandibular lesions did not improve despite repeated operations over 14 months. Bisphosphonate therapy was withdrawn and parathyroid hormone therapy was started after 2 months the oral mucosa had healed, after 4 months the pain had completely subsided, and after 6 months the patient s eating and drinking habits had returned. The serum concentration of osteocalcin, a marker of bone formation, which was initially suppressed, increased by 174% from baseline after 6 months of treatment with parathyroid hormone. 

A buccal drug delivery system is applied to a specific area on the buccal membrane. Moreover, the delivery system ean be designed to be unidirectional in drug release so that it can be protected from the loeal environment of the oral cavity. It also permits the inclusion of a permeation enhancer/protease inhibitor or pH modifier in the formulation to modulate the membrane or the tablet-mucosal environment at that particular application site. While the irritation is limited to the well-defined area, the systemic toxicity of these enhancers/inhibitors and modifiers can be reduced. The buccal mucosa is well suited for this type of modification as it is less prone to irreversible damage [9]. In the event of drug toxicity, delivery can be terminated promptly by removal of the dosage form. 

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