COMPARATIVE SEM STUDY ON THE EFFECT OF ACID ETCHING WITH TETRACYCLINEHCL OR CITRIC-ACID ON INSTRUMENTED PERIODONTALLY-INVOLVED HUMAN ROOT SURFACES

THIS STUDY COMPARED THE SURFACE CHARACTERISTICS of periodontally disea sed single-rooted human teeth extracted after treatment with either te tracycline HCl or citric acid solutions. The study group was comprised of 30 teeth from 22 patients with advanced periodontal disease extrac ted before the start of periodontal therapy. Diseased surfaces were id entified, outlined, and root planed by hand curet or finishing bur. Th e teeth were sectioned and solutions of tetracycline HCl or citric aci d (pH 1) were applied to the surfaces with cotton pellets for 5 minute s. Extracted teeth were processed and root surface samples then examin ed by scanning electron microscope. The surfaces of both acid-treated sets of specimens differed considerably from specimens treated with ro ot planing alone, regardless of root planing method. Acid-treated spec imens exhibited dentinal tubules exposed by the removal of the smear l ayer, surfaces devoid of the debris normally present in root planed-on ly specimens, and the dense network of collagen fibers that make up th e dentin structure. Although differences were seen in surface depressi ons and fiber-like structures among some specimens, the tetracycline H Cl and citric acid solutions produced comparable morphologic character istics.