Clinical evaluation of ultrasonic subgingival debridement versus ultrasonic subgingival scaling combined with manual root planing in the treatment of periodontitis: study protocol for a randomized controlled trial

Background: Periodontal diseases are regarded as the most common diseases of mankind. The prevalence rate of periodontal disease assumes a clear growth tendency, increasing by 57.3% from 1990 to 2010. Thereby, effective periodontal therapy is still a long-term task and a difficult problem. The goals of periodontal therapy are to eliminate the infectious and inflammatory processes of periodontal diseases. Root planing, in order to eliminate the "infected cementum," has been an important step in the treatment of periodontitis since the 1970s. However, along with the understanding of the effects of endotoxin on the root surface, the necessity of manual root planing has been gradually queried. Ultrasonic instruments, which are more recent innovations, would not remove the cementum excessively, and are also more time-saving and labor-saving compared to using hand instruments. Hence, an increasing number of dentists prefer to do scaling with ultrasonic instruments only. However, the necessity of root planing remains emphasized in the international mainstream views of periodontal mechanical treatment. Therefore, this study is devoted to compare the clinical effect of ultrasonic subgingival debridement and ultrasonic subgingival scaling combined with manual root planing, which takes the implementation of root planing as the only variable and is more in line with the current clinical situation, thus hoping to provide some valuable reference to dentists. Methods/design: Forty adult patients who fit the inclusion criteria are being recruited from the Peking University Hospital of Stomatology (Beijing, China). By means of randomization tables, one quadrant of the upper and lower teeth is the test group and the other is the control group. Test group: ultrasonic subgingival scaling combined with manual root planing. Control group: ultrasonic subgingival debridement. In a 24-week follow-up period, plaque index, probing depth, clinical attachment loss, bleeding index, furcation involvement, mobility, and patient-reported outcome (Visual Analog Scale for pain and sensitivity) will be observed and documented. Discussion: This study evaluates the effectiveness of ultrasonic subgingival scaling combined with manual root planing and ultrasonic subgingival debridement alone in the nonsurgical treatment of periodontitis with a split-mouth design after 1, 3 and 6 months. The result of the trial should potentially contribute to an advanced treatment strategy for periodontitis with an ideal clinical outcome.