Bone Abstracts

Objectives: The aim of the study was to establish features of macroelemental composition of the dentin in mature male rat’s mandibular incisors with biogenic hydroxyapatite, implanted in the proximal part of tibial shaft.

Material and methods: One hundred and twenty-six mature male rats were divided into three groups: 1st group – intact animals, 2nd group – animals with the pit defect applied on the proximal part of tibial shaft (systematic osteoporosis model), 3rd group – implanted into the defected area the blocks of biogenic hydroxyapatite. Periods of experiment were 7, 15, 30, 60, 90 and 180 days. Rats were killed under ether mask anesthesia. To measure the macroelement’s content in dentin 10 mg dental ashes were dissolved in 2 ml of 0.1 N HCl, chemically pure, adjusted to 25 ml distilled water. The resulting solution was determined in calcium, sodium, potassium by atomic absorption photometer of the ‘Saturn-2’ in the mode of emission of air-propane flame and phosphorus colorimetrically by Briggs.

Results: Content of calcium and phosphorus in the dentin incisor in 2nd group was similar with 3rd along the whole experimental period. Sodium content increases per day, starting from the 1st month up to the 60th day (at 7.33%, 6.88%), potassium – at 10.89%, 11.66%, but on the 90th and 180th experimental days there was a tendency to reduce the content of these macroelements in the dentin incisor. Fluorine content increased only on the 90th days at 6.68% (P<0.05), compared with the intact animals.

Conclusions: Thus, in animals with defect in the tibia we establish imbalance of macroelemental composition in dentin of incisor. Presence of the biogenic hydroxyapatite, implanted into the tibia, improved the chemical content of the dentin on the late stages (from 90 to 180 day of observation).