Oral Environment 1 - Oral Fluids Flashcards
What is included in the oral fluids
saliva, gingival crevicular fluid, oral bacteria, food debris, epithelial cells
what are the 2 main functions of oral fluids?
protection and digestion
what are the protective functions of oral fluids?
cleansing, mucosal protection, buffering, remineralisation and antimicrobial
what are the digestive functions of oral fluids
taste, digestive enzymes, lubricates bolus for chewing, swallowing
what can occur as a consequence of reduced salivary flow?
increased incidence of dental caries
what type of glands are salivary glands?
exocrine glands
what is the arrangement of salivary glands?
compound, tubulo-acinar arrangement
what do major salivary glands appear like?
anatomically distinct and identifiable glands
what do minor salivary glands appear as?
more diffuse collections of glandular tissue lying in the lamina propria
what are the major salivary glands?
parotid, submandibular and sublingual
what are the minor salivary glands and where are they?
buccal (in cheek), labial (in lip), lingual (in tongue) and palatal (in hard and soft palate)
what are the different parts of the salivary gland?
acinus, capsule, septa, lobe, secretory units, intercalated ducts and striated collecting ducts
what do serous acinus glands appear as histologically?
puffy pink circles with nuclei peripherally dotted
what do mixed acinus glands appear as histologically?
white puffy circles (mucous part) with pink (serous) around the outside and only a few nuclei
what do mucous acinus glands appear as histologically?
white cells with nuclei located peripherally
what do striated duct glands appear as histologically
smooth pink cells with nuclei located semi-peripherally
what major salivary gland has serous secretions?
parotid
what major salivary gland has mixed secretions?
submandibular
what major salivary gland has mucous secretion?
sublingual
which minor salivary glands have mucous secretions only?
buccal, labial and palatal
what minor salivary gland has serous and mucous secretions?
lingual
what is gingival crevicular fluid?
fluid from epithelium lining the gingival crevice (sulcus)
when is there more gingival crevicular fluid present?
when there is inflammation in the gingivae e.g. gingivitis
what salivary gland contributes the most to stimulated salivary flow?
parotid
when is the submandibular gland most active?
when awake and at rest
when is the sublingual gland most active
when asleep
what gland contributes most to salivary flow when sleeping?
submandibular
what are the factors affecting unstimulated salivary flow rate?
state of hydration, previous stimulation, circadian rhythms, circannual rhythms, medications and salivary gland disease
what is the inorganic composition of saliva made of?
water (99.5%) and ions (0.2%)
what is the organic composition of saliva made of?
mainly proteins (0.3%) and little carbohydrate or lipid
what are the different ions in saliva?
fluoride, calcium and phosphate, thiocyanate, bicarbonate and phosphates
what is the function of fluoride in saliva?
antibacterial, forms fluoroapatite, promotes remineralisation
what is the function of calcium and phosphate in saliva?
remineralisation
what is the function of thiocyanate in saliva?
antibacterial
what is the function of bicarbonate and phosphates in saliva?
buffering
when is bicarbonate as a buffer effective?
high flow rates
when is phosphate effective as a buffer?
at rest
when is proteins effective as a buffer?
when the pH is less than 5
when is bacterial sodium hydroxide effective as a buffer?
it buffers plaque acid
