Bioceramics Volume 12, edited by II. Okgushi, G. W. Hastings and T. Yoshikawa (Proceedings of the 12th International Symposium on Ceramics in Medicine) Nara, Japan, October 1999 © 1999 World Scientific Publishing Co. Pte. Ltd. TEMPORAL CHANGES IN CLINICAL RESPONSES OF HUMAN PERIODONTAL DEFECTS TREATED WITH OPEN FLAP DEBRIDEMENT OR BIOACTIVE GLASS OVER 6-12 MONTH HEALING PERIOD S. Froum'-'md M. Wcinbcrg: New York University College of Dentistry. Department of Implant Dentistry. 345 E. 24* Street. New York. NY. department of Surgical Sciences (Pcriodontics). ABSTRACT The purpose ofthc present investigation was to clinically evaluate over a 6-12 month postsurgical period changes in the healing response of human intraosseous delects treated with open flap debridement with and without Bioglass® implantation. Patients were chosen for this study if they had at least 2 sites with attachment loss of > 6 mm and radiographic evidence of intraosseous defects. Clinical measurements (probing depths (FD), attachment level (AL), and gingival recession (Rec) were recorded at baseline (da\ of the surgery), 6 and 12 months. The test defects were implanted with bioactive glass Ihe other sites served as unimplanted controls. At 1 year, significantly greater (P=0.()430) mean probing depth reduction was noted in the bioactive glass group (3.42 mm) compared to the control (4.31 mm) Attachment level gain was significantly improved (P=0.0016) in the bioactive glass sites (2.96 mm) compared to the control sites (1.48 mm). There was significantly less (!J=0.0!90) gingival recession in the bioaclive glass sites (1.36 mm) compared to the control sites (1.90 mm). In conclusion, bioactive glass showed significant improvement in clinical parameters compared to open (lap debridement alone Moreover, changes in clinical parameters (PD reduction and AI, gain) recorded 6 months postsurgery remained stable at the 12-month evaluation Changes in Rec recorded at 12 months were significantly greater (P=.O1O4) than the 6 month values in both treatment groups. KEY WORDS: bioactive glass; periodontal diseases/surgery; periodontal diseases/treatment, open tlap debridemenl, Bioglass® INTRODUCTION The ultimate goal of periodontal therapy is focused on the elimination of hard and soft tissue defects (e.g., probing depths and osseous defects) by regenerating new attachment. This new attachment ideally consists of new bone, cementum, and attached periodontal ligament to replace that which was lost due to periodontal disease. Methods to evaluate the clinical results of various therapies has focused on measuring clinical parameters of probing depth (I'D), attachment levels (AI.) and gingival recession (Rec) prior to and al various postsurgical lime intervals Traditionally reevaluation measurements take place 6 or 12 months postsurgery However, the difference between the 6 and 12-month results has rarely been tested A variety of materials and procedures have been utilized to obtain periodontal regeneration including use of bone grafts and bone replacement materials. Recently there has been renewed interest in evaluating alloplasts as bone substitute materials in the treatment of intraosseous defects. One such material, which has shown positive clinical results, is bioactive glass Bioglass® (Perioglas®, Block Drug Inc., Jersey City, NJ) is a bioactive glass that demonstrates osteoconduction by having a bioactive surface that is coloni/.ed by osteogenic stem cells7 and the ability to bond to soft tissue and bone.2"1 New attachment has been shown in both animal7 and human studiess" comparing Bioglass® and other ceramics to open flap debridement ITie purpose of the present investigation was to clinically evaluate over a 6-12 month postsurgical period changes in the healing response of human intraosseous defects treated with open flap debridement with and without Bioglass® implantation. 37 38 Bioceramics Volume IS MATERIAL AND METHODS Sixteen systemically healthy patients, 8 males and 8 females, with an average age of 43 years were selected for this study. Hach patienl had localized moderate to severe penodontitis with two or more sites in dillerent quadrants with attachment loss > 6 mm. ITiesc situs exhibited clinical and radiographic evidence of intraosscous defects ]~he patients hid not taken antibiotics within 6 months of the start of the study and were not allergic to any medications used in this study Hach patient had undergone cause-related therapy at least I to 3 months prior to enrollment in the study. ITiis consisted of oral hygiene instruction, scaling and root planing and occlusal therapy where indicated, l'rior to surgery, a customized acrylic sterit was fabricated for each patient. The stent was grooved in an occlusal apical direction with a bur so that a number 5(1 silver point was returned to the same position for each successive measurement Sort and hard tissue measurements were recorded from a fixed reference point (stent) to the nearest 0.01 mm using a digital Boley gauge, silver point, and locking pliers. ITie following clinical measurements were recorded at baseline (just prior to surgery), 6 months, and 12 months after surgery: probing depth (PD), attachment level (Ah), and gingival recession (Rec). Six and 12-month clinical changes form baseline measurements were compared to each other to evaluate changes during this time period SURGICAL PROTOCOL Sites were selected by the flip of a coin and designated as test (t) or control (c) Following administration of local anesthesia, buccal and lingual intrasulcular incisions were made and full thickness ilaps were elevated. After debnderrenl of the osseous defect, the root surfaces were scaled and root planed. Wherever there was no observable inlramarrow bleeding, small penetrations through the bony walls were made with a Vi round bur or curct tip. Itic control sites were then sutured with interrupted sutures. I'he test sites were treated in the same manner I [owever, following debridernent of the root and bone defect, the bioactive glass was implanted to fill the defects to the most coronal level of the osseous walls. All patients received systemic tetracycline IIC1 1 gm/day for 14 days postsurgery and were instructed to rinse with 0.12% chlorhexidine gluconate twice daily until the sutures were removed I week later. Patients were seen for pcriodonlal supportive therapy at the surgical sites weekly for 6 weeks then monthly for the next lO'/J months RESULTS Summary of mean soft tissue measurements at baseline, 6 and 12 (Table 1) Table 1: Summary of LS-Mean Soft Tissue Measurements at Post-Surg months postsurgery Baseline, 6 and 12 Months Clinical Parameter Initial Pocket Depth (PD) 6 -Month Change in PD 12-Month Change in PD 6-Month Clinical Attachment Level (CAL) 12-Month Clinical Attachment Level 6-Month Change in Remssion 12-Monlh Change in Remssion Control LS-Mcantt (a-23 defects) 7.31 3.14 3.42 1.36 148 1.63 1.90 SE 0.37 0.29 0.32 0.26 0.33 0.16 0.17 Test LS-Meant (n-27 defects) 7.85 4.03 4.31 2.92 2.96 0.96 1.36 SE 0.37 0.30 0.33 0.26 0.33 0.16 0.17 ANOVA P-Valuc 0.2815 0.0276t 0.0430 t 0.000 It 0.0016t 0,0029 t 0.01901 (Statistically significant differences were detected in the means between the control and test treatment groups using a 2-group randomized block analysis of variance with subjects considered as randomized blocks. }'l"he l,S-means arc means which have been weighted to account for the variable number of defects assessed in the control or test quadrants in each subject. Temporal Changes m Clinical Responses of Human Periodontal Defects ... 39 A 2-group randomized block analysis of variance (ANOVA) with patients considered as randomized blocks was used to compare mean change from baseline per individual site in soft tissue measurements. A comparison was made between the debridement and biouctive glass treatments of probing depth, clinical attachment level and recession. For each outcome measurement, least-squares (LS) means, standard errors (SE), and 95% confidence intervals (CI) were estimated for change from baseline at each postsurgery observation time. There was a statistically significant (P = 0,0276) mean reduction in probing depths at the test sites (4,03 nun) compared to the control sites (3.14 mm) at 6 months posl-op. There was a significant (P=0.0001) attachment level gain in the test sites (2.92 mm) compared to the control sites (1.36 mm). The mean change in gingival recession from baseline to 6 months postsurgery was significantly lower (P=0.(X)29) in the test sites (0.96 mm) compared to the control sites (1.63 mm). '["here was a statistically significant (P = 0.0430) mean reduction in probing depths at the test sites (4.31 mm) compared to the control sites (3.42 mm) at 12 months post -op. There was a significant (P=0.0016) attachment level gain in the test sites (2.96 mm) compared to the control sites (1 48 mm) The mean change in gingival recession from baseline to 12 months was statistically lower (P=0.0190) in the test sites (1.36 mm) compared to the control sites (1 90 mm) Comparison of the 6 an 12 month post surgical results (Table 2) Table 2: Comparison of Probing Depth, Attachment Level and Gingival Recession Changes at 6 and 12 Months Post-Surgery Repeated Measures ANOVA Results Treatment Parameter Time' Time *Trt .Group Interaction2 Croup3 0.0197t 0.000 It O.OO27t tStatistically significant differences were delected using a repeated measures analysis of variance This is a test for a difference in the change from baseline from six, to twelve months. :This is a tesl to sec if the time effect (from 6 to 12-months) is the same for the two treatments. control and test iThis is a test to see if the two treatments have an effect on the mean change from baseline Repeated measures ANOVA, with the patient again considered as a randomized block and observation time post surgery considered as a repeated factor was used to determine if differences ui change from baseline existed between the 6-month and 12 month results. Also, a test was done to see if a lime effect, if anv between the 6 month and 12 month values, differed between the two treatment groups There were no significant time and treatment group interactions for pocket depth, clinical attachment level, or recession indicating that the temporal effects, if any, were the same in the two treatment groups. A significant time effect was found for the changes from baseline in recession between the 6 month and 12 month data (p=0.0104) with more recession at 12 months versus at 6 months in both treatment groups, lhcre were no significant differences found between the 6 month and 12 month mean changes from baseline in probmg depth (P=0.1855). There was no time effect found. Pocket Depth Clinical Attachment Level Recession 0.1855 0.7198 0.0104 t 0.9873 0.8262 0.586? •10 Bioceramics Volume 12 DISCUSSION I in. prcscni stuih compare! L 1IIHL.I1 paumetci probing dcpihs gjngival recession and attachment level following open debridement with and without implantation of a bioactive glass. The findings that the btoactive glass treated sites showed significantly more probing depth reduction and attachment level gain than the open debndement treated sites is in agreement with Ong et al D 1 Iowever, the magnitude of change in both the test and control treated sites was greater in this study ITus may have been attributed to differences in patient population, defect morphology, or plaque control. In fact clinical changes in both I'D reduction and AL gain has been shown to correlate with plaque control ' The results of the present study also show that the clinical improvement in PD and AL is maintained over a 6 to 12 month penod. This is consistent with the finding of Low ct al.5 who showed that PI) reduction and AL gain was stable over a 24 month period following use of bioactive glass to treat penodontal osseous defects in 12 patients. Implications of these results are that soil: tissue changes following open llap debndement with or without Bioglass® implants maybe evaluated 6 months postsurgcry However, statistically significant changes do take place in gmgival recession from 6 to 12 months postsurgery with more recession at 12 months. The question of whether new histological attachment and/or bone fill can be assessed al this time period remains to be answered Moreover, the reasons for changes in recession and whether these changes will continue to show significance after 1 vear must also be further studied Conclusions that can be gleaned from these studies include the fact that the improvement in clinical parameters following open flap debriJement with the use of a bioactive glass arc significantly enhanced over open flap debndement alone. Moreover, clinical improvements in PI) and AL gain when evaluated 6 months postsurgery are stable for at least an additional 6 months iflow plaque levels are maintained. REFERENCES 1. Froum SJ, Coran M, Thaller H, Kushner L, Scopp IW, Stahl SS. J Periodontol 1982; 53 :8-14. 2. i Icnch LL, Paschal HA. I Biomed Mater Res 1973; 7 :2542. 3. Hench LL, Splinter RJ, Allen WC, Cfrecnlec TK. J Biomed Mater Res 1971; 2 :117-141. 4 llench LL, Wilson J. Science 1984: 226 630-636 5. lx>w SB, King CJ, Knegcr J. Int J Pcnodont Rest Dent 1997; 17 :359-367. 6. Ong MMA, Hber RM, Korsnes MI, MacNeil RL, Glickman ON, Shyr Y, Wang 1IL J Penodontol 1998, 69 : 1346-1354. 7. Wilson J, Low SB. J App Biomaler 1992; 3 123-129