Effect of metabolic acidosis on dentinogenesis in rat

To determine if dentinogenesis is affected in systemic acidosis, chronic metabolic acidosis was induced in 3-week-old rats for 3,5,6 and 7 weeks with 0.25 mol/l of NH4Cl in their drinking water. One set of rats were fed on a high-sucrose diet (43% sucrose) and another on a standard laboratory rat food. Tetracycline was given to mark the areas of dentin formation during the test period. At the end of the experiment acid-base status was tested by blood gas analysis. After sacrifice, the areas of tetracycline marked new dentin were measured from sagittally sectioned mandibular molars. Metabolic acidosis significantly reduced rat growth and dentin apposition. The high-sucrose diet enhanced the reducing effect of the acidotic drinking water on dentin growth, and also caused a mild metabolic acidosis without NH4Cl in drinking water.