In vivo recalcification of dentin demineralized by citric acid.

Acid-treatment of root surfaces as adjunct to periodontal reconstructive surgery may have deleterious effects on that part which remains in a supragingival location after healing. The present experiment aimed to examine whether recalcification of such root surfaces may occur. Cylindrical blocks of root dentin were prepared for 10 premolars, treated with citric acid and mounted in acrylic specimen holders which were worn in the mouth continuously for 14 d by two test subjects. The specimens were then sectioned and microradiographs produced. The citric acid had produced a completely demineralized surface zone in the root dentin and the subjacent hard tissue showed a zone of partially reduced mineral content. Following exposure to the oral cavity, the demineralized surface layer appeared unchanged in width. The subjacent zone, however, had been reduced in width in all instances when compared with control specimens from the same teeth.