Abstract
The aim of this study was to evaluate the effect of parotid saliva on the rate of salivary clearance on the upper posterior buccal surfaces. To determine the exact position of the parotid duct opening, alginate impressions were taken of the upper jaw and stone models were made. Subjects for whom the parotid gland opening position was almost identical were selected. To determine the rate of potassium chloride clearance,1 mol/l KCl in a 1.0% agarose matrix was used as the diffusant, which was placed in acrylic devices. The diffusion chambers were taken from the mouth at selected time intervals and the gels transferred quantitatively to flasks containing 300 ml of 100 ppm NaCl, and then analyzed for potassium using atomic absorption spectrophotometry. The velocity of the salivary film at the upper posterior buccal surface of the tooth was also estimated with this equipment, which designed by Dawes.
The following resulte were obtained:
1. The opening position of the parotid duct in 13 subjects showed a large degree of deviation
2. The rates of salivary clearance at the second premolar, first molar and second molar of the upper jaw differed significantly from each other, and the highest value was found at the first molar.
3. The direction of salivary flow from the opening of the parotid duct was forward in the unstimulated salivation and backward in the stimulated salivation.
4. The estimated velocity of the salivary film varied with different tooth surfaces, and the highest velocity was found for the first molar.
