This case report presents an unusual complication, cervical root resorption, after a conventional connective tissue grafting procedure and tetracycline root conditioning. The recession was 7 mm high, with 0.5 mm of keratinized tissue present, a 2-mm probing depth, and was classified as Miller Class III. The clinical result was satisfactory and 5 mm of root coverage was achieved. However, after 20 months, cervical resorption was diagnosed. It is suggested that tetracycline root conditioning may cause root resorption in long-term evaluations. There is also a possibility of root resorption occurring in 1-year postoperative controls. Other factors will be discussed in relation to this negative clinical result.