independent periodontist by assessing the ideal height of the interdental papilla. The distance from the apical reference point of a stent (StRP) and the MRC was ...
J Periodontol • July 2010
Case Series
Predetermination of Root Coverage Giovanni Zucchelli,* Monica Mele,* Martina Stefanini,* Claudio Mazzotti,* Ilham Mounssif,* Matteo Marzadori,* and Lucio Montebugnoli†
Background: A method to predetermine the maximum root coverage level (MRC) achievable with surgery was recently presented. The present study evaluates the predictability of such a method by comparing the predetermined MRC with that effectively achieved by means of root coverage surgical procedures. Methods: A total of 50 patients with single and multiple recession defects were enrolled. MRC was predetermined by an independent periodontist by assessing the ideal height of the interdental papilla. The distance from the apical reference point of a stent (StRP) and the MRC was measured 7 days before root coverage surgery. A total of 135 Miller Class I, II, and III gingival recessions were treated with the coronally advanced flap (CAF) or with the subepithelial connective tissue graft (SCTG). The distance from StRP and the gingival margin (GM) was measured by another independent periodontist 15, 30, and 90 days after surgery. Results: In 97 (71.8%) of 135 treated gingival recessions, the StRP-MRC distance coincided exactly with the StRP-GM distance. No statistically significant difference was demonstrated in the cases with exact predetermination between gingival recessions belonging to the maxilla or mandible and between gingival defects treated with CAF or SCTG. The StRP-MRC distance measured before surgery was greater in 24 recession defects (17.7%) and lower in 14 gingival recessions (10.3%) than the StRP-GM distance measured 90 days after surgery. More cases of underestimation and fewer cases with overestimation of the level of root coverage were found in the SCTG group compared to the CAF group. The difference was statistically significant (P 10 cigarettes a day; recession defects associated with buccal caries, and teeth with evidence of pulpal pathology; and molar teeth were excluded. Study Design This was a pilot, double-masked, case-series study comparing the predetermined MRC to that achieved after root coverage surgical procedures: coronally advanced flap (CAF) with and without a subepithelial connective tissue graft (SCTG). The study protocol involved a screening appointment to verify eligibility, followed by initial therapy to establish optimal plaque control and gingival health conditions; predetermination of MRC, measurement of the apical reference point of the stent (StRP)-MRC distance, and surgical therapy; and early maintenance phase and postoperative assessments of the StRP-GM distance 15, 30, and 90 days after the surgery. Ninety days was chosen as the final follow-up measurement visit because at this time the outcome of the surgery can be considered
J Periodontol • July 2010
clinically stable and not yet influenced by the maintenance phase. Initial Therapy Following the screening examination, all subjects received a session of prophylaxis including instruction in proper oral hygiene measures, scaling, and professional tooth cleaning with the use of a rubber cup and a low-abrasive polishing paste. A coronally directed roll technique was prescribed for teeth with recession-type defects to minimize toothbrushing trauma to the GM. Surgical treatment of the recession defect was not scheduled until the patient could demonstrate an adequate standard of supragingival plaque control. Stent Preparation At baseline, a stent was fabricated using resin‡ material directly in the mouth. A reference point (slot) was impressed on the stent at the mid-buccal area of the experimental tooth to allow reproducible periodontal probe positioning. The apical margin of the stent was linear and served as a measurement reference point (Fig. 1).8 Predetermination of Root Coverage The method used to predetermine the MRC in the present study was recently published by the same research group and was based on the calculation of the ideal height of the anatomic interdental papilla.5 The ideal height of the papilla in a tooth with gingival recession was defined as the apical-coronal dimension of the interdental papilla capable of ‘‘supporting’’ complete root coverage.5 In a non-rotated and malpositioned tooth the ideal height of the papilla was measured at the same tooth with gingival recession, whereas in a rotated and malpositioned tooth it was measured at the level of the homologous, controlateral tooth. The ideal height of the papilla was measured as the distance between the mesial-distal line angle of the tooth and the contact point. The line angle is easily identifiable, even in a tooth with buccal abrasion defect, by elevating the interdental soft tissues (with a probe or small spatula) and searching for the interdental CEJ. Once the ideal papilla was measured, this dimension was replaced apically starting from the tip of the mesial and distal papillae of the tooth with the recession defect. The horizontal projections on the recession margin of these measurements allowed for identification of two points that were connected by a scalloped line, representing the ‘‘line of root coverage.’’5 At the mid-buccal surface of the teeth with gingival recessions, the distance from the StRP and the most apical extension of the line of root coverage, representing the MRC, was measured with a manual pressure-sensitive probe§ equipped with a spring devicei and measurements were rounded
Zucchelli, Mele, Stefanini, et al.
up to the nearest 0.5 mm (Fig. 1). These measurements were performed by a single masked examiner (MM) 7 days before the surgeries. She did not perform the surgeries and did not make the clinical measurements after surgery. Before the study the examiner was calibrated to reduce intraexaminer error (k >0.75) to establish reliability and consistency. Clinical Measurements Clinical measurements were carried out by a single masked examiner (CM). He did not perform the surgeries and was unaware of the predetermined level of root coverage. Before the study, the examiner was calibrated to reduce intraexaminer error (k >0.75) to establish reliability and consistency. Full-mouth and local plaque scores were recorded 1 week before the surgery (baseline) and 3 months after the surgery as the percentage of total surfaces (four aspects per tooth) that revealed the presence of plaque.9 Bleeding on probing was assessed dichotomously at a force of 0.3 N with the manual pressuresensitive probe. Full-mouth and local bleeding scores were recorded as the percentage of total surfaces (four aspects per tooth) that bled on probing. The distance from the StRP and the most apical extension of the GM was measured at baseline, 15, 30, and 90 days after the surgery at the mid-buccal aspect of the study teeth (Fig. 1). Probing depth, the distance from the GM to the bottom of gingival sulcus, was measured at baseline and 3 months after surgery. All measurements were rounded up to the nearest 0.5 mm. Surgical Techniques The surgeries were performed by an experienced periodontist (GZ). He was unaware of the predetermined level of root coverage and did not make the clinical measurements. Based on his own experience the periodontist (GZ) decided to perform a CAF with (SCTG) or without connective tissue graft. Main factors influencing the decision to add a connective tissue graft were the lack of keratinized tissue apical to the root exposure, the need to increase the soft tissue thickness,10 and the presence of a deep abrasion defect (Fig. 2). In the case of single-type recession defects, the modified CAF approach described by De Sanctis and Zucchelli11 was used, whereas the envelope-type of CAF described by Zucchelli and De Sanctis12 was performed in the case of multiple gingival recessions affecting adjacent teeth in the same quadrant of the jaw. Post-surgical Infection Control Patients were instructed not to brush teeth in the treated area, but rinse for 1 minute with a 0.12% ‡ Pattern Resin, GC Italy, San Giuliano Milanese, Italy. § PCP-UNC 15 probe tip, Hu-Friedy, Chicago, IL. i Brodontic spring device, Dentramar, Waalwijk, Holland.
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Root Coverage Predetermination
Volume 81 • Number 7
Figure 1. A) Distance between StRP and GM measured at baseline at the mid-buccal aspect of a study tooth. B) Distance between StRP and MRC at the mid-buccal aspect of a study tooth. C) Distance between StRP and GM measured 15 days after surgery, at time of suture removal, at the mid-buccal aspect of a study tooth. D) Distance between SRP and GM measured 90 days after the surgery at the midbuccal aspect of a study tooth. This distance coincides with the distance SRP-MRC measured before surgery.
chlorhexidine solution three times a day. Fourteen days after the surgical treatment, the sutures were removed. Plaque control in the surgically treated area was maintained by rinsing with chlorhexidine for an additional 2 weeks. After this period, patients were again instructed in mechanical tooth cleaning of the treated tooth using an ultrasoft toothbrush and a roll technique for 1 month. During this period, the chlorhexidine rinse was used twice a day. Then, patients were instructed to use a soft toothbrush and rinse with chlorhexidine once a day for another month. All patients were recalled for prophylaxis 2 and 4 weeks after suture removal and, subsequently, once a month until the final examination (90 days). Data Analyses A statistical software program¶ was used for the statistical analyses. Descriptive statistics were expressed as mean – SD. One-way analyses were performed to see whether standardized skewness and kurtosis values regarding the StRP-GM distance 15, 30, and 90 days after 1022
surgery were within the range expected for data from a normal distribution (i.e., within the range of -2 and +2). Thus, a general linear model was fitted and multiple-regression analysis of variance for repeated measures with teeth nested in patients was used to evaluate the existence of any significant timerelated difference (15, 30, and 90 days after surgery) regarding the StRP-GM distance. In case of significance, the Bonferroni t test was applied as a multiple comparison test. A general model, considering teeth nested in patients, was also fitted to relate the agreement (presence or absence of any significant difference in the coincidence between the StRP-MRC distance measured before the surgery and the StRP-GM distance measured 90 days after the surgery) with the two techniques (CAF versus SCTG) and the jaw (gingival recessions belonging to the mandible or maxilla) and to relate the number of cases with overestimation and underestimation of the level of root coverage between the two techniques (CAF versus SCTG).
RESULTS Following the initial oral hygiene phase and at the post-treatment examinations, all subjects showed low frequencies of plaque-harboring tooth surfaces (full-mouth plaque score
