Background: The goal of guided tissue regenerationbased root coverage (GTRC) is to repair gingival recession via new attachment formation. Numerous clinical trials have been conducted utilizing the concept of GTR to promote root coverage. Most GTRC studies have had relatively small sample sizes and have not utilized power calculations to determine appropriate sample size; therefore, it is difficult to draw strong conclusions from them. Hence, the purpose of this study is to combine data from currently available GTRC studies and to use meta‐analysis to determine whether GTRC provides significantly improved clinical outcomes compared to conventional periodontal plastic surgical approaches for the treatment of marginal tissue recession.Methods: Studies were identified that used GTR approaches to treat gingival recession from January 1990 to October 2001. Information from each study was entered into a database. Data were analyzed according to the following criteria: GTRC versus conventional mucogingival surgery (CMGS); membrane type; root conditioning; pretreatment recession depth; adjunctive use of bone replacement graft (BRG); and source of funding. Studies were ranked independently, and mean data from each were weighted accordingly. Meta‐analysis was performed using the weighted means for each group. Paired t tests were used to determine statistical significance between each pair of groups.Results: Forty papers were included for analysis. GTRC resulted in an average of 74% recession depth reduction, 41% complete root coverage, 3 mm AL gain, and 1 mm KG gain. Both GTRC and CMGS produced significant (P <0.05) improvement compared to baseline measurements. Compared to GTRC, CMGS resulted in significantly (P<0.05) increased KG (2.1 mm vs. 1.1 mm), root coverage (81% vs. 74%), and percentage of defects with complete root coverage (55% vs. 41%). Use of absorbable membranes, root conditioning, shallow pretreatment recession (<4 mm), and corporate sponsorship all resulted in significantly (P<0.05) improved percentages of sites with complete root coverage but had no effect on other parameters.Conclusions: Based on this meta‐analysis, guided tissue regeneration‐based root coverage can be used successfully to repair gingival recession defects. Conventional mucogingival surgery, however, resulted in statistically better root coverage, width of keratinized gingiva, and complete root coverage. J Periodontol 2003;74:1520‐1533.

Background: Use of collagen membrane (CM) with xenograft and recombinant human platelet‐derived growth factor (rhPDGF) in guided bone regeneration (GBR) is debatable. The aim of this microcomputed tomographic experiment was to assess the efficacy of using PDGF and xenograft (with or without CM) for GBR around immediate implants with dehiscence defects.Methods: Ten beagle dogs underwent atraumatic bilateral second and fourth premolar extractions from both arches. A standardized dehiscence defect (6 × 3 mm) was created on the buccal bone and immediate implants were placed in distal sockets in each site. Animals were randomly divided into three groups: 1) group 1, xenograft with rhPDGF was placed and covered with CM; 2) group 2, xenograft with rhPDGF was placed over the defects; and 3) group 3, four immediate implants were associated with dehiscence (controls). After 16 weeks, animals were sacrificed and jaw segments were assessed for buccal bone thickness (BBT), buccal bone volume (BBV), vertical bone height (VBH), and bone‐to‐implant contact (BIC) using microcomputed tomography.Results: BBT was higher in group 2 (1.533 ± 0.89 mm) than group 1 (0.745 ± 0.322 mm) (P <0.001) and group 3 (0.257 ± 0.232 mm) (P <0.05). BBV was higher in group 2 (67.87 ± 19.83 mm³) than group 1 (42.47 ± 6.78 mm³) (P <0.05) and group 3 (19.12 ± 4.06 mm³) (P <0.001). VBH was higher in group 2 (6.36 ± 1.37 mm) than group 3 (0.00 ± 0.00 mm) (P <0.001). VBH was higher in group 1 (3.91 ± 2.68 mm) than group 3 (0.00 ± 0.00 mm) (P <0.05). BIC was higher in group 2 (67.25% ± 13.42%) than group 1 (36.25% ± 12.78%) (P <0.05) and group 3 (30.25% ± 7.27%) (P <0.01).Conclusion: GBR around immediate implants with dehiscence defects using PDGF and xenograft alone resulted in higher BBT, BBV, VBH, and BIC than when performed in combination with CM.

Objective: Chitosan is a promising polymer that has been used for coating dental implants. However, research concerning coatings with implant surfaces other than commercially pure titanium is limited. Therefore, this study aims to clarify the chitosan material's effect with two degrees of deacetylation (DDA) as coatings for laser surface microtopographic implants. Methods: Sixty-three Laser-Lok (LL) implant discs were divided into three groups (21 in each group), and two groups were coated with either 80 or 95 DDA chitosan. The groups were categorized as LL 95, LL 80, or LL control. Then, hMSC-TERT 20 cells were used to evaluate the cell morphology, viability, and osteogenic capacity of the chitosan material 7 and 14 days after culture. Two-way ANOVA followed by one-way analysis of variance (ANOVA) and Tukey’s post hoc test were used. Results: All samples were biocompatible and allowed cell attachment. However, cell spreading and attachment were noticeably increased in the LL 95 group. There was a significant increase in the expression of osteogenic markers in chitosan-coated samples compared to the control group. The 95 DDA-coated group exhibited higher ALP, Runx2, osteocalcin, and osteonectin expression compared to the 80 DDA and control groups on days 7 and 14. Conclusion: A high DDA of chitosan promotes biomineralization and osteoblast formation. Therefore, this combination of laser surface and chitosan can enhance future dental implant healing processes and osseointegration.

Objectives. To study root caries and risk profiles using the Cariogram in relation to periodontal disease severity and to analyse indicators associated with high caries risk. Material and methods. A cross-sectional examination was carried out on 112 patients with periodontal disease from two government clinics in Saudi Arabia. The investigation comprised a questionnaire, bitewing radiographs, measurement of salivary secretion rate, buffering capacity and cariogenic microorganisms, and registration of periodontal status, plaque amount and coronal and root caries/fillings (DFT and RDFT). The data were then entered into the Cariogram pedagogic model to illustrate the caries risk profiles. Results. Patients were grouped according to periodontal disease severity into one of three groups: (1) gingivitis (n = 44); (2) mild-to-moderate periodontitis (n = 33); and (3) severe periodontitis (n = 35). The prevalence of RDFT in the total sample was 17%. There were no statistically significant differences between the three groups in number of root lesions or mean ‘Actual Chance to Avoid New Cavities’ (Chance-AC) according to the Cariogram. Of the total sample, 22% displayed high caries risk (Chance-AC ≤40%). The most significant risk indicators in high caries risk patients were infrequent use of fluoride and unfavourable salivary and microbial parameters. Conclusions. Root surface lesions and high caries risk were present in about one-fifth of the patients referred for periodontal treatment. A combination of risk indicators rather than a single one contributed to the increased risk. Caries and risk profiles were not significantly correlated with periodontal disease severity.