Treatment of localized gingival recessions with coronally displaced flaps and citric acid. An experimental study in the dog.

The present study was designed to examine the effect of citric acid conditioning on the result of healing following treatment of localized gingival recessions with coronally displaced flaps. In 3 beagle dogs, localized gingival recessions were surgically created at the buccal surfaces of canines, premolars and molars. All experimental sites were allowed to accumulate plaque for a period of 6 months. Following preparation of notches in the buccal root surfaces at the level of the gingival margin, buccal and lingual mucoperiosteal flaps were raised. The exposed portion of the root surfaces was scaled and the cementum layer was removed. Another notch was prepared in the root surfaces at the level of the crest of the alveolar bone. Half the number of the roots were treated by topical application of citric acid while the remaining roots were used as non-acid treated controls. The flaps were sutured in a coronally displaced position. After 3 months of healing, the dogs were sacrificed and the jaws removed and placed in fixative. After decalcification, histological sections of the experimental roots and their periodontal tissues were produced. The 2 notches described above were used as reference points in the histological examination. The histological analysis disclosed that new attachment had formed on all test and control roots and extended in some specimens of both groups to a position coronal to the presurgical level of the gingival margin. The amount of new attachment was similar in the 2 categories of roots, demonstrating that citric acid conditioning did not produce additional new attachment.