Gingival Margin Position Research Articles

A Comparative Evaluation for Biologic Width following Surgical Crown Lengthening Using Gingivectomy and Ostectomy Procedure

Surgical crown lengthening has been proposed as a means of facilitating restorative procedures and preventing injuries in teeth with structurally inadequate clinical crown or exposing tooth structure in the presence of deep, subgingival pathologies which may hamper the access for proper restorative measures. Histological studies utilizing animal models have shown that postoperative crestal resorption allowed reestablishment of the biologic width. However, very little has been done in humans. Aims. The purpose of the study was to evaluate the potential changes in the periodontal tissues, particularly the biologic width, following surgical crown lengthening by two surgical procedures before and after crown placement. Methods and Material. Twenty (20) patients who needed surgical crown lengthening to gain retention necessary for prosthetic treatment and/or to access caries, tooth fracture, or previous prosthetic margins entered the study. The following parameters were obtained from line angles of treated teeth (teeth requiring surgical crown lengthening) and adjacent sites: Plaque and Gingival Indices (PI) & (GI), Position of Gingival Margin from reference Stent (PGMRS), Probing depth (PD), and Biologic Width (BW). Statistical Analysis Used. Student “t” Test. Results. Initial baseline values of biologic width were 2.55 mm (Gingivectomy procedure B1 Group) and 1.95 mm (Ostectomy procedure B2 Group) and after surgical procedure the values were 1.15 mm and 1.25 mm. Conclusions. Within the limitations of the study the biologic width, at treated sites, was re-established to its original vertical dimension by 3 months. Ostectomy with apically positioned flap can be considered as a more effective procedure than Gingivectomy for Surgical Crown Lengthening.

Impact of supragingival therapy on subgingival microbial profile in smokers versus non-smokers with severe chronic periodontitis

BackgroundThe aim of this study was to assess subgingival microbiological changes in smokers versus non-smokers presenting severe chronic periodontitis after supragingival periodontal therapy (ST).MethodsNon-smokers (n=10) and smokers (n=10) presenting at least nine teeth with probing pocket depth (PPD) (≥5 mm), bleeding on probing (BoP), and no history of periodontal treatment in the last 6 months were selected. Clinical parameters assessed were plaque index (PI), BoP, PPD, relative gingival margin position (rGMP) and relative clinical attachment level (rCAL). Subgingival biofilm was collected before and 21 days after ST. DNA was extracted and the 16S rRNA gene was amplified with the universal primer pair, 27F and 1492R. Amplified genes were cloned, sequenced, and identified by comparison with known 16S rRNA sequences. Statistical analysis was performed by Student's t and Chi-Square tests (α=5%).ResultsClinically, ST promoted a significant reduction in PI and PPD, and gain of rCAL for both groups, with no significant intergroup difference. Microbiologically, at baseline, data analysis demonstrated that smokers harbored a higher proportion of Porphyromonas endodontalis, Bacteroidetes sp., Fusobacterium sp. and Tannerella forsythia and a lower number of cultivated phylotypes (p<0.05). Furthermore, non-smokers featured significant reductions in key phylotypes associated with periodontitis, whereas smokers presented more modest changes.ConclusionWithin the limits of the present study, ST promoted comparable clinical improvements in smokers and non-smokers with severe chronic periodontitis. However, in smokers, ST only slightly affected the subgingival biofilm biodiversity, as compared with non-smokers.

Clinical evaluation of chlorhexidine and essential oils for adjunctive effects in ultrasonic instrumentation of furcation involvements: a randomized controlled clinical trial

The aim of this clinical study was to evaluate and compare the clinical efficacy of subgingival ultrasonic mechanical instrumentation (UMI) irrigated with essential oils (EOs) and chlorhexidine (CHX) at the furcation involvements (FI). Forty-five patients (244 FI) who presented with Class II FI were recruited to the study. Patients were randomly assigned to CHX (UMI irrigated with 0.2% CHX), EO (UMI irrigated with EOs) or control (UMI irrigated with distilled water) groups. All treatments were performed in one session. For all groups, plaque index (PI), gingival index (GI), position of gingival margin (PGM), pocket depth (PD), bleeding on probing (BOP), clinical attachment level (CAL) and horizontal attachment level (HAL) scores were recorded at baseline and 1 and 3 months after therapy. In all groups, there were significant reductions in PI, GI, PD and BOP, increase in PGM scores and gain in CAL and HAL scores, at 1 and 3 months compared to baseline. Except in BOP scores, there were no significance differences among the groups at any time point. At 1 and 3 months, there were significant reductions in the BOP scores of the EO group compared with the CHX and control groups. Within the limits of this study, the use of EOs as a cooling liquid of UMI may promote slight adjunctive effects at FI compared to CHX and water.

Evaluation of the polylactide-polyglycolide copolymer Fisiograft® in the treatment of intrabony defects: Clinical and radiographic results of a pilot study

Aim: To evaluate the efficacy of the polylactide-polyglycolide copolymer Fisiograft® as a bone graft material in the treatment of interproximal intrabony defects clinically and radiographically. Methods: A total of 22 intrabony defects in 8 patients with chronic periodontitis (4 males and 4 females) aged 20 to 55 years were recruited and divided equally into two groups: control (open flap debridement alone) and experimental (open flap debridement with Fisiograft®). Recordings of probing pocket depth (PPD), clinical attachment level (CAL), gingival margin position (GMP) and radiovisiographic assessment was done at baseline and 6 months. Results: Statistical analysis was done by Wilcoxon Signed Rank test for intra-group comparisons and Mann-Whitney U-test for inter-group comparisons. The clinical parameters PPD, CAL and GMP were found to be statistically significant (p<0.05) within each group. Inter-group comparison showed only the CAL gain to be statistically significant (p<0.01). In relation to hard tissue changes, statistically significant (p=0.05) result was seen for the percent filling of the original defect, comparing the experimental and control groups 6 months postoperatively. Conclusions: Placement of Fisiograft® resulted in better healing of intrabony defects as assessed clinically and radiographically when compared to open flap debridement alone.

Comparative Evaluation of Platelet-rich Plasma and Guided Tissue Regeneration Membrane in the Healing of Apicomarginal Defects: A Clinical Study

Introduction The aim of the study was to compare the healing responses of platelet-rich plasma (PRP), PRP + a collagen sponge, and a collagen membrane used as guided tissue regeneration (GTR) materials for the treatment of apicomarginal defects. Methods Thirty patients with suppurative chronic apical periodontitis and apicomarginal communication were selected and allocated randomly into three groups according to the barrier technique to be used during periradicular surgery: the collagen membrane group, the PRP group, and the PRP + collagen sponge group. Clinical and radiographic measurements were determined at baseline and every 3 months after surgery up to 1 year. Cases were defined as healed when no clinical signs or symptoms were present, and radiographs showed complete or incomplete (scar tissue) healing of previous radiolucencies. Results The PRP and PRP + collagen sponge groups depicted 83.33% and 88.89% healing, respectively, in terms of combined clinical-radiographic healing as compared with 80% in the collagen membrane group. All the three treatments showed highly significant ( P < .05) reductions in the periodontal pocket depth (PD), the clinical attachment level (CAL), the gingival margin position (GMP), the size of the periapical lesion, the percentage reduction of the periapical rarefactions, and periapical healing. No significant differences between the three groups were evident for these parameters ( P > .05). Conclusions GTR applied to apicomarginal defects using PRP or PRP + collagen sponge lead to similar enhancements of the clinical outcome of periradicular surgery in terms of periapical healing, gain of periodontal support, PD reduction, and PRP may be an alternative treatment for GTR membrane in the treatment of apicomarginal defects.

Efficacy of palatal connective tissue graft as a membrane in the treatment of intrabony defects

Background and aims. The aim of this study was to compare clinical effects of two different membranes (palatal connective tissue and collagen) in combination with Bio-Oss in the treatment of intrabony defects. Materials and methods. Fifteen patients who had at least a pair of intrabony defects with an attachment loss of ≥5 mm and an initial osseous defect depth of ≥3 mm participated in this study. Probing pocket depth, clinical attachment level, position of gingival margin, bony defect depth and position of alveolar crest were measured before surgery and in re-entry procedure 9 months after treatment. Results. The results of this study showed that both techniques were effective in the treatment of intra-bony defects and both treatment modalities resulted in significant differences in all the parameters before and after surgery (P<0.05). Conclusion. It was shown that, after treatment, considering all the variables in each group, there were significant improvements, but there were not any statistical differences in any of the variables between the two groups.

Altered passive eruption (APE):A little-known clinical situation

Gummy smile constitutes a relatively frequent aesthetic alteration characterized by excessive exhibition of the gums during smiling movements of the upper lip. It is the result of an inadequate relation between the lower edge of the upper lip, the positioning of the anterosuperior teeth, the location of the upper jaw, and the gingival margin position with respect to the dental crown. Altered Passive Eruption (APE) is a clinical situation produced by excessive gum overlapping over the enamel limits, resulting in a short clinical crown appearance, that gives the sensation of hidden teeth. The term itself suggests the causal mechanism, i.e., failure in the passive phase of dental eruption, though there is no scientific evidence to support this. While there are some authors who consider APE to be a risk situation for periodontal health, its clearest clinical implication refers to oral esthetics. APE is a factor that frequently contributes to the presence of a gummy or gingival smile, and it can easily be corrected by periodontal surgery. Nevertheless, it is essential to establish a correct differential diagnosis and good treatment plan. A literature review is presented of the dental eruption process, etiological hypotheses of APE, its morphologic classification, and its clinical relevance.

Retraction Note to: Gingival health in relation to clinical crown length: a case report

Gingival margin position in relation to synthetic crowns and crown length could be etiological factors in gingival health. A 27-year-old male presented with necrotizing ulcerative gingivitis with short clinical crowns suggestive of altered passive eruption. Three years after the initial diagnosis, he presented with crowns on the maxillary incisors. There were short clinical crowns and marked gingival inflammation. Placement of the crown margin could be an etiological factor in gingival inflammation. Therefore, should the margin be subgingival, equigingival or supragingival?

Clinical evaluation of topical subgingival application of biodegradable xanthan based 1.5% Chlorhexidine gel for treatment of periodontal pockets

Background & Objectives: Local delivery of antimicrobials in sustained or controlled delivery systems are used to enhance the effect of non-surgical periodontal therapy; it might be possible to achieve gingival health without the need for invasive techniques with the use of local drug delivery systems. Thus the aim of the present study was to evaluate efficacy of topical subgingival application of xanthan based 1.5% chlorhexidine gel in the treatment of periodontal pockets. Methods: A randomized controlled clinical trial was carried out for a period of 6 months. 60 sites in 10 patients suffering from chronic periodontitis were divided into experimental and control sites. The experimental sites were treated with Scaling & root planing (SRP) in combination with subgingival application of biodegradable Xanthan based 1.5 % chlorhexidine gel. The control sites received SRP & subgingival application of placebo gel. Plaque index (PI) Gingival index (GI), Probing pocket depth (PD), clinical attachment level (CAL) and gingival margin position (GMP) were recorded at baseline, 3 & 6 months. Results: All the treatments showed significant reductions in PI, GI, PPD, CAL at 3 & 6 months when compared to baseline values (p<0.05). At 6 months, experimental group showed significantly greater improvement in all clinical parameters than control group. The difference between PPD reduction between the treatment groups were 3.0 & 2.4 mm at 3 & 6 months, respectively (p<0.001). For CAL these were 3.11 & 2.4 mm, respectively (p<0.001). The mean percentages of probing depth reduction & clinical attachment level gain ≥ 2 mm were greater in the experimental sites than control sites (p<0.001). Interpretation & Conclusion: Overall, both therapies led to significant improvements of the investigated parameters. The adjunctive use of Xanthan based 1.5% chlorhexidine gel showed greater PPD reductions CAL gains compared to combination of SRP & placebo gel.

Enamel matrix derivative proteins for the treatment of proximal class II furcation involvements: a prospective 24‐month randomized clinical trial

This study aimed to evaluate the response of proximal furcations treated with enamel matrix derivative proteins (EMD) in a 24-month follow-up. Twelve patients presenting bilateral class II proximal furcation with vertical probing depth (PD) ≥5 mm and bleeding on probing were selected. The furcations were assigned to: a control group (n=12), open flap debridement (OFD)+EDTA and a test group (n=12) - OFD+EDTA+EMD. The gingival margin position, PD, relative vertical and horizontal clinical attachment level (RVCAL and RHCAL), vertical and horizontal bone level (VBL and HBL) and furcation closure were evaluated before treatment and after 6, 12 and 24 months. After follow-up, no statistical difference could be seen between groups. At 24 months, the test group showed 1.9 ± 1.6 mm PD reduction whereas the control group showed 1.0 ± 1.3 mm PD reduction. RHCAL gains of the control and the test group were 0.7 ± 1.3 and 1.4 ± 0.9 mm, respectively. However, at 24 months, the test group only presented five remaining class II furcations versus 10 furcations in the control group (p<0.05). It could be concluded that EMD therapy promoted a reduction in the number of proximal furcations presenting a diagnosis of class II after 24 months of treatment compared with OFD therapy.

Free Gingival Grafts: Graft Shrinkage and Donor‐Site Healing in Smokers and Non‐Smokers

This prospective clinical study aims to evaluate the influence of cigarette smoking on free gingival graft (FGG) healing, by assessing FGG dimensional changes and donor-site wound healing. Twelve non-smokers and 10 smokers treatment planned for FGG to augment keratinized tissue dimensions in the mandibular incisor area completed the study. All subjects received standardized FGG of same dimensions. Probing depth, gingival margin position, clinical attachment level, keratinized tissue (KT) width, gingival thickness, and FGG dimensions (width, length, and area) were assessed and recorded before surgery, and 7, 15, 30, 60, and 90 days postoperatively. The palatal donor area was evaluated for immediate bleeding and complete wound epithelialization. Differences between the two groups (smokers and non-smokers) were statistically analyzed. FGG dimensions changed significantly postoperatively. At 90 days postoperatively, FGG width, length, and area were respectively reduced by 31%, 22%, and 44% in non-smokers and by 44%, 25%, and 58% in smokers (no significant differences between groups; P >0.05). Significant KT increases were observed in both non-smokers and smokers (5.4 and 4.8 mm, respectively). Donor-site immediate bleeding was significantly more prevalent in non-smokers (75%) compared to smokers (30%) (P = 0.04). At 15 days postoperatively, donor-site complete epithelialization was much more prevalent in non-smokers (92%) than in smokers (20%) (P <0.002). Smoking alters FGG donor-site wound healing by reducing immediate bleeding incidence and by delaying epithelialization, although it does not have discernible effects on postoperative FGG dimensional changes.

Evaluation of HTR polymer (Bioplant® HTR® ) as a bone graft material in the treatment of interproximal vertical bony defects: A clinical and radiological study

Bone grafting is the most common form of regenerative therapy. Several bone substitutes have been used in clinical periodontal therapy to encourage bone formation. The present study has been undertaken to evaluate the efficacy of hard tissue replacement polymer (Bioplant HTR) as a bone graft material in the treatment of interproximal vertical bony defects in human beings, both clinically and radiologically. Five chronic periodontitis patients were selected with 16 sites assigned randomly into control (open debridement alone) and experimental (open flap debridement plus Bioplant HTR) groups. Clinical measurements like plaque index (PI), gingival index (GI), probing pocket depth (PPD), clinical attachment level (CAL), gingival margin position (GMP) assessment was done at 0, 3 and 6 months and radiographic assessment at 0 and 6 month. Statistical analysis was performed using Wilcoxon's signed Rank test and Mann-whitney U-test. There were statistically no significant (P=1.00) changes in Plaque index and Gingival Index scores in both the groups from baseline to six months post surgery. Statistically significant (P<0.05) reduction in Probing Pocket Depth was seen on comparison between the groups. In relation to the hard tissue changes, significant results were seen with respect to change in alveolar crest and percentage of original defect resolved. Comparison of results from six to 12 months following similar treatments showed no significant differences or advantages to having a clinical evaluation period longer than 6 months post surgically (Yukna 1999). Bioplant HTR material is a biocompatible, easy to handle and a beneficial grafting material for the treatment of periodontal osseous defects.

Prospective Evaluation of Immediate and Delayed Provisional Single Tooth Restorations

The purpose of this study was 2-fold: to determine whether there is a significant difference in the hard and soft tissue response comparing immediate with delayed implant placement after tooth removal, with immediate provisionalization, in maxillary anterior sites; and to determine and compare the crestal bone levels as the primary endpoint variable for implants placed and immediately temporized in extraction sites, to implants placed into extraction sites after the extraction site has been grafted and healed for 4 months, all immediately restored with an anatomic provisional restoration. This aim was to be evaluated by measuring crestal bone levels on standardized digital radiographs of the implants, using implant threads as a monitor of magnification and a pre-extraction reference. Secondary endpoint variables include soft tissue measures compared with method. A total of 76 patients were recruited and randomized into treatment groups. Group 1 had a maxillary tooth (premolar, canine, lateral or central incisor) removed, with immediate socket grafting, followed by implant placement and provisionalization 4 months later with a single tooth. Group 2 had immediate implant placement and provisionalization. Standardized radiograph holders were used to expose digital radiographs every 6 months from baseline to up to 2 years restored. Soft tissue measures were made from standardized reference points. Data collected were analyzed by a statistician to test the hypotheses. A total of 55 patients completed their follow-up. Twenty-one patients were lost to follow-up because of implant loss (n = 5), 1 treated out of protocol because of labial bone loss found at the time of tooth removal (n = 1), geographic relocation (n = 11), dropped for noncompliance (n = 3), or medical problems (n = 1). The analyses showed no significant differences between groups in implant integration or crestal interdental bone movement on either the implant or the adjacent tooth. The bone level on the implants did move from the baseline levels during the first 6 months but not thereafter. There were no differences (P > .05) observed when comparing the interactions between groups, tooth locations, or time. There was a significant (P < .05) difference in the position of the facial gingival margin with a more apical position of the facial gingival margin in the delayed group compared with the immediate group during the course of the study. Crestal bone response to immediate or delayed placement of an implant into an extraction site in the maxillary anterior region with immediate provisionalization is similar regarding hard tissue changes. Support of the gingival margin with a provisional at the time of tooth extraction and implant placement preserved 1 mm more facial gingival margin position compared with the delayed group. The decision to use either method must consider the movement of the facial gingival margin, which, in a critical esthetic patient may require soft tissue support from a provisional restoration or similar type of anatomical healing abutment.

Gingival health in relation to clinical crown length: a case report.

Gingival margin position in relation to synthetic crowns and crown length could be etiological factors in gingival health. A 27-year-old male presented with necrotizing ulcerative gingivitis with short clinical crowns suggestive of altered passive eruption. Three years after the initial diagnosis, he presented with crowns on the maxillary incisors. There were short clinical crowns and marked gingival inflammation. Placement of the crown margin could be an etiological factor in gingival inflammation. Therefore, should the margin be subgingival, equigingival or supragingival?

Alterations of the marginal soft tissue (gingival margin) following periodontal therapy: A clinical study

Background and Objectives:The evaluation of gingival margin position (GMP) plays a vital role in periodontal therapy and is critical in esthetic/plastic surgical procedures revolving around restorative dentistry. Comparative evaluations of GMP measurements in various periodontal therapies are scarce. Thus, the objectives of this study are to measure the alteration in the gingival margin position following various therapies, and to compare GMP alterations among different treatment modalities from the baseline to six months after therapy.Materials and Methods:The changes in GMP were studied for MB, B, DB, ML, and L sites for SRP, curettage, and flap surgery, and for MB, B, and DB sites for crown lengthening cases at the end of one, three, and six months after therapy. The results were interpreted from baseline to one, three, and six months posttreatment.Statistical Analysis:The results were subjected to statistical analysis. Paired ‘t’-test was used for intra-group comparisons and intergroup comparisons were done by one-way ANOVA.Results:The GMP changed from baseline in all the sites at different time periods following various therapies. The net results after six months were an apical shift of GMP in SRP, curettage, and flap surgery, and a coronal shift of GMP in crown lengthening.Conclusion:GMP shows various patterns of alteration after various periodontal therapies. One should wait for the GMP to become stable before attempting any restorative procedure.

Evaluation of a New Furcation Stent as a Fixed Reference Point for Class II Furcation Measurements

To date probing of the furcation using sounding has been one of the reliable methods to assess horizontal component of furcation in multirooted teeth. A more precise and reliable measurement of this horizontal component of furcation involves using a fixed reference point providing stability and reproducibility of measurements. A custom stent is used to provide a fixed reference point and can be used pre- and post-surgically without re-entry. Therefore, the purposes of this study were to (1) assess the reliability of furcation measurements by direct probing (without stent) and with the use of a newly designed furcation stent and (2) to assess the furcation measurements in relation to gingival margin position pre- and post-operatively. Forty-three chronic periodontitis patients with buccal grade II furcation involvement in maxillary or mandibular molars were included. The furcation involvement was measured by direct probing using a UNC-15 calibrated probe with and without using a custom stent. The furcation involvement and gingival margin position were measured pre- and post-surgically. There was a significant reduction in plaque (PI) and gingival inflammation (GI) during the study period. The reduction in plaque index and gingival index was observed from 1.75 +/- 0.35 to 0.92 +/- 0.30, 1.88 +/- 0.35 to 0.98 +/- 0.29, respectively. Complete agreement was found between the first and the second measurement for about 74% of sites without the custom stent, whereas 86% of the sites measured using the stent had complete agreement. The differences never exceeded 1 mm for any of the sites. There was significant (t = 2.49; p<0.05) difference observed at complete agreement level ('0' difference). It may be concluded the clinical attachment level-H of the furcation involvement using a PCP UNC-15 probe and a custom designed stent provides reproducible information about the furcation depth in multirooted teeth. Use of a simple modified furcation stent has shown greater reproducibility of furcal depth measurements than direct probing without the stent. The furcation stent definitely addresses the problems of existing methods of horizontal furcal depth measurements reported in the literature. The major advantages of the newly designed stent are the simple construction and non-invasive application which translates to wide practical applications.

Periodontal debridement as a therapeutic approach for severe chronic periodontitis: a clinical, microbiological and immunological study

To clinically, microbiologically and immunologically characterize periodontal debridement as a therapeutic approach for severe chronic periodontitis. Twenty-five patients presenting at least eight teeth with a probing pocket depth (PPD) of >or=5 mm and bleeding on probing (BOP) were selected and randomly assigned to quadrant-wise scaling and root planing or one session of full-mouth periodontal debridement. The following clinical outcomes were assessed: plaque index, BOP, position of gingival margin, relative attachment level (RAL) and PPD. Real-time PCR was used for quantitative analysis of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Tannerella forsythia. The enzyme-linked immunosorbent assay permitted the detection of IL-1beta, prostaglandin E(2), INF-gamma and IL-10 in gingival crevicular fluid (GCF). All the parameters were evaluated at baseline, and at 3 and 6 months after treatment. Both the groups had similar means of PPD reduction and attachment gain over time. Besides a significant reduction in the bacterial level after treatment in both groups, microbiological analysis failed to demonstrate significant differences between them. Finally, no difference was observed between groups with respect to the levels of inflammatory mediators in GCF. Periodontal debridement resulted in a similar clinical, microbiological and immunological outcome when compared with standard scaling and root planing and therefore may be a viable approach to deal with severe chronic periodontitis.

A double‐blind randomized clinical evaluation of enamel matrix derivative proteins for the treatment of proximal class‐II furcation involvements

The aim of the present randomized, double-blind study was to evaluate the clinical response of proximal furcations treated with enamel matrix derivative proteins (EMD). Fifteen patients, each with a pair of contralateral class-II proximal furcation involvements, presenting probing depths (PDs) >/=5 mm and bleeding on probing (BOP) were selected. The patients were randomly assigned to: control group (n=15) - open flap debridement (OFD)+24% ethylenediaminetetraacetic acid (EDTA) conditioning; test group (n=15) - OFD+24% EDTA conditioning+EMD application. Plaque index (PI), BOP, PD, gingival margin position (GMP), relative vertical and horizontal clinical attachment level (RVCAL and RHCAL), vertical and horizontal bone level (VBL and HBL) and furcation closure were evaluated immediately before and 2, 4 and 6 months after the surgeries. At 6 months, the RVCAL gains of the control and test group were 0.39 +/- 1.00 and 0.54 +/- 0.95 mm, while the RHCAL gains were 1.21 +/- 2.28 and 1.36 +/- 1.26 mm (p>0.05). The VBL and HBL gains of the control group were 1.04 +/- 1.12 and 1.00 +/- 1.79 mm, and 0.82 +/- 1.82 and 1.17 +/- 1.38 mm for the test group (p>0.05). In addition, a statistical difference was observed in the number of the remaining class-II furcations between the test and control groups (p<0.05) in this period. It may be concluded that the use of EMD in proximal furcations did not promote a superior reduction in PD or a gain in clinical and osseous attachment levels, but resulted in a higher rate of class-II to class-I furcation conversion.

Gingival margin alterations and the pre-orthodontic treatment amount of keratinized gingiva

The purpose of this retrospective study was to associate the amount of keratinized gingiva present in adolescents prior to orthodontic treatment to the development of gingival recessions after the end of treatment. The sample consisted of the intra-oral photographs and orthodontic study models from 209 Caucasian patients with a mean age of 11.20 +/- 1.83 years on their initial records and 14.7 +/- 1.8 years on their final records. Patients were either Angle Class I or II and were submitted to non-extraction orthodontic treatment. Gingival recession was evaluated by visual inspection of the lower incisors and canines as seen in the initial and final study models and intra-oral photographs. The amount of recession was quantified using a digital caliper and the observed post-treatment gingival margin alterations were classified as unaltered, coronal migration of the gingival margin or apical migration of the gingival margin. The width of the keratinized gingiva was measured from the mucogingival line to the gingival margin on the pre-treatment photographs. The teeth that developed gingival recession and those that did not have their gingival margin position changed did not differ in relation to the initial amount of keratinized gingiva (3.00 +/- 0.61 and 3.5 +/- 0.86 mm, respectively). Paradoxically, teeth that presented a coronal migration of the gingival margin had a smaller initial amount of keratinized gingiva (2.26 +/- 0.31 mm). The mean amount of initial keratinized gingiva did not predispose lower incisors and canines to gingival recession.

Healing response of apicomarginal defects to two guided tissue regeneration techniques in periradicular surgery: a double‐blind, randomized‐clinical trial

To compare healing responses to periosteal sliding grafts and polyglactin 910 periodontal mesh used as guided tissue regeneration (GTR) materials/techniques when both periapical and periradicular bone loss are present. Thirty patients with suppurative chronic apical periodontitis with apicomarginal communication were selected and allocated randomly into two groups according to the barrier technique to be used during periradicular surgery: periosteal graft group (n = 15) and bioabsorbable membrane group (n = 15). Clinical and radiological evaluations were completed prior to surgery, a week later and every 3 months after surgery up to 12 months to measure the periodontal pocket depth (PD), clinical attachment level (CAL), gingival margin position (GMP), size of periapical lesion, percentage reduction of the periapical rarefaction, and periapical healing. Both groups showed highly significant (P < 0.001) reductions in periodontal PD, CAL and size of periapical lesion at 12 months whilst GMP was unaltered. No significant difference between the experimental groups was evident for these parameters, or for the percentage reduction of size of the periapical lesion and clinical-radiographic healing. Guided tissue regeneration applied to apicomarginal defects using sliding periosteal grafts and use of bioabsorbable membranes led to similar enhancements of the clinical outcome of periradicular surgery in terms of periapical healing, gain of periodontal support, PD reduction and minimal recession of the gingival margin.