Oral mucosa salivary glands

Unlike the skin, the mucosae of the oral cavity are constantly maintained moist by the continual secretion of saliva from the three major salivary glands (submandibular, parotid, and sublingual) and the minor salivary glands located in or beneath the mucosae. The thickness of the salivary film (pellicle) has been calculated to be between 70 /rm and 100 /./m [23] however, both the composition and amount of saliva produced can vary between individuals, with time of day, disease states, and drug therapy [33], all of which must be taken into account when considering the oral cavity as a site for drug delivery. 

Pharmacokinetics Slowly, incompletely absorbed affer oral administration. Food delays or decreases the extent of absorption. Protein binding Negligible. Primarily distributed to intestinal mucosa and salivary glands. Primarily excreted unchanged in urine. Removed by hemodialysis. Half-life 3-6 hr. 

If a major salivary gland is lost from trauma or disease, or if nasal allergies or sinus infections cause persistent mouth-breathing, or if tobacco smoking persists, the oral cavity becomes dry (xerostomia). The oral mucosa and teeth become covered with bacteria and dental caries and periodontal disease become difficult to control. The functions of whole... 

Dental fluoride gels are normally acidic in order to obtain a better effect. However, when the salivary glands are damaged by radiation or chemotherapy, the acidic licensed preparations are often not tolerated, as they will be too irritant on the mucosa. A neutral dental fluoride gel, prepared in the pharmacy, would be the medicine of choice. Formulations containing ethanol can also irritate a damaged oral mucosa. 

When saliva production is insufficient, many different liquids can be used. They vary from glycerol with citric acid to the saliva substitutes already mentioned in Sect. 7.1. Citric acid stimulates the saliva production in the salivary glands, and therefore raises the amount of saliva in the mouth. If there is damage to the oral mucosa, it is best to avoid ethanol and propylene glycol, because these solvents may cause irritation, A German hospital developed an... 

Between the two mucosal layers covering the soft palate (i.e., nasal and oral mucosa) there are mixed salivary glands, a few taste buds, muscle fibres, fatty tissue and a complex of connective tissue fibres originating from the aponeurosis of tensor veli palatini muscle. 

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