4.6. Pilot studies

Before running the experiments described above, six pilot groups were made with six corresponding control groups. These animals were Long Evans rats and they were three weeks old at the beginning of the experiments. All these groups were fed on the high-sucrose diet. Metabolic acidosis was induced for three and five weeks, metabolic alkalosis for seven and nine weeks, respiratory alkalosis for seven and respiratory acidosis for six weeks. The rats with respiratory acidosis were kept in a hyperbaric chamber (1.5 bar) containing 27% of oxygen and 0.03% of carbon dioxide in nitrogen. The other disturbances in acid-base balance were created the same way as above.

The dentine formation was measured basically the same way as mentioned before, but older equipments were used. Because of that, and also because of the different rat strain, the results can not be compared to those of the experimental groups. Thus, percentages of the increase or decrease in weight gain, dentine formation and dentinal caries compared to the corresponding control groups were calculated. Dentinal caries was explored by using Schiff reagent. No statistical analyses were performed for the pilot groups.