The Effect of Time on Root Coverage Outcomes: A Network Meta-analysis.

The stability of root coverage outcomes has gained a great deal of interest. However, insufficient evidence is available, mainly due to limited direct comparisons among different techniques and the small sample size among clinical trials. Therefore, the aim of this study was to propose a mixed-models network meta-analysis (NMA) that includes the novelty of assessing time on root coverage outcomes while simultaneously comparing different surgical approaches. A literature search was performed by 2 individual reviewers to identify randomized clinical trials (RCTs) reporting the outcomes of root coverage procedures of at least 2 time points to estimate the slopes of different treatment approaches. The primary outcomes were the changes in slopes for recession depth (REC), keratinized tissue width (KTW), and clinical attachment level. Sixty RCTs with a total of 2,554 gingival recessions (1,864 patients) were included in the NMA. Connective tissue graft (CTG) and enamel matrix derivative (EMD) approaches provided superior initial REC reduction compared to flap advancement alone. However, only CTG-based procedures were effective in maintaining the stability of the gingival margin over time, while EMD, acellular dermal matrix, collagen matrix, and flap alone showed a similar tendency for gingival recession recurrence. Baseline REC and KTW at the earliest postoperative recall were predictors for the stability of the gingival margin. In addition, a geographic center effect on the treatment slopes was observed for REC and KTW. While limitations of the present linear mixed-modeling approach should be considered as it refers to estimation and comparison of time slopes based on an examined while linear framework, the designed NMA showed to be an effective tool for the simultaneous comparison of multiple treatment approaches while taking into account the critical element of time.

Local wound healing biomarkers for real-time assessment of periodontal regeneration: pilot study.

BACKGROUND AND OBJECTIVES: Within the same surgical procedure, a great variability on achievement of clinical outcomes exists and may be associated to different molecular factors related to tissue healing. The aim of the present study was to assess the distribution of clinical success separately in regenerative therapy (REG) and open flap debridement (OFD) to evaluate if factors related with healing of epithelium, connective tissue and bone may be associated to the clinical outcome within each surgical procedure. MATERIAL AND METHODS: Sixteen patients underwent periodontal REG and nine patients underwent OFD. Periodontal wound fluid was collected at baseline, 3-5, 7, 14 and 21 d after surgery, and expression of wound healing proteins was assessed. Pocket depth and clinical attachment level were taken at baseline and at 6 mo of follow-up. Percentage pocket depth reduction and percentage clinical attachment level gain were computed. Patients were regarded as better or worse responders depending on their percentage pocket depth reduction or percentage clinical attachment level gain. RESULTS: Higher percentage of better responders was observed in the REG group (68.7%) compared to the OFD group (22.2%). At 21 d, no difference in the profile of most of the proteins emerged, with two exceptions, both regarding REG treatment. Bone morphogenetic protein-7 tended to increase in better responders and to decrease in worse responders. Matrix metalloproteinase-1 increased in worse responders and remained substantially unchanged in better responders. CONCLUSION: Local expression of matrix metalloproteinase-1 and bone morphogenetic protein-7 during wound healing is associated with the clinical performance of periodontal regenerative surgery. The use of local biomarkers offers the potential for real-time assessment of the periodontal healing process.

Bone repair cells for craniofacial regeneration.

Reconstruction of complex craniofacial deformities is a clinical challenge in situations of injury, congenital defects or disease. The use of cell-based therapies represents one of the most advanced methods for enhancing the regenerative response for craniofacial wound healing. Both somatic and stem cells have been adopted in the treatment of complex osseous defects and advances have been made in finding the most adequate scaffold for the delivery of cell therapies in human regenerative medicine. As an example of such approaches for clinical application for craniofacial regeneration, Ixmyelocel-T or bone repair cells are a source of bone marrow derived stem and progenitor cells. They are produced through the use of single pass perfusion bioreactors for CD90+ mesenchymal stem cells and CD14+ monocyte/macrophage progenitor cells. The application of ixmyelocel-T has shown potential in the regeneration of muscular, vascular, nervous and osseous tissue. The purpose of this manuscript is to highlight cell therapies used to repair bony and soft tissue defects in the oral and craniofacial complex. The field at this point remains at an early stage, however this review will provide insights into the progress being made using cell therapies for eventual development into clinical practice.

In vivo early plaque formation on zirconia and feldspathic ceramic.

AIM: Zirconia is a ceramic material with optimal aesthetic and mechanical properties that make it adapt to esthetic recontructions in narrow spaces. Aim of this split mouth clinical trial is to compare amount and structure of early plaque coated to zirconia and feldspathic ceramic. METHODS: Four patients were included in this study. A removable acrylic device was manufactured for each subject and equipped on the lingual surface in correspondence to molar teeth with eight specimens. Four zirconia samples were positioned on the right side (test) of the device, and 4 feldspathic ceramic samples were positioned on the left side (control). One test and one control samples were harvested from each device at 6, 12, 24 and 36 hours after oral environment exposition. A total of four samples for each group were collected at each timepoint; three of these were used for reverse transcription polymerase chain reaction analysis to evaluate the bacteria plaque amount; the remaining sample was used for scanning electron microscopy analysis to observe the bacteria plaque structure. RESULTS: No significant differences were detected in terms of bacteria amount between test and control group at each timepoint. At scanning electron microscopy evaluation especially at 36 hou, bacteria plaque structure coated to zirconia surface appeared less uniform and compact compared to feldspathic ceramic. CONCLUSION: Zirconia material may be considered adapt to prosthetic reconstructions that require high mechanical and aesthetic properties and that are exposed to the oral environment.

Effect of enamel matrix derivative on human periodontal fibroblasts: proliferation, morphology and root surface colonization. An in vitro study.

BACKGROUND: Several clinical trials have shown the effectiveness of Emdogain(R) (EMD) in promoting tissue regeneration, even though the underlining biological mechanism is still poorly known. OBJECTIVES: The aim of the present study was to verify the effect of EMD on the proliferation of human periodontal ligament (PDL) fibroblasts and on their colonization and differentiation following contact with the root surface of extracted teeth in vitro. METHODS AND RESULTS: Fibroblasts from PDL were seeded on Petri dishes and cell growth was evaluated by cell counting in the presence and absence of EMD, after 1, 3 and 8 d of culture. A significant effect of EMD upon cellular proliferation at d 3 and 8 was detected. When PDL cells were grown for 12 d with EMD on etched human root surface, a change in cell morphology was observed. Scanning electron microscopy revealed that cells grown on root EMD-treated surface present a body with a flattened surface closely adherent to the substrate and an outer smooth surface rounded in shape. From the flattened surface some thin and elongated cellular processes connecting with the substrate were also observable. PDL cells grown on EMD-treated surface showed lack of alkaline phosphatase activity, as some authors noticed in cementoblasts in vitro. CONCLUSIONS: In conclusion, our data indicate that EMD enhances human PDL fibroblast proliferation. Furthermore, the cells in the presence of EMD show morphological changes that make them more similar to cementoblasts than to fibroblasts, suggesting a process of cellular differentiation that could play an important role in periodontal tissue repair.

Comparison of treatments of infrabony defects with enamel matrix derivative, guided tissue regeneration with a nonresorbable membrane and Widman modified flap. A pilot study.

BACKGROUND, AIMS: The purpose of the present study was to compare the efficacy of 3 different surgical procedures in the treatment of infrabony defects: guided tissue regeneration (GTR) with non-resorbable membranes, Widman modified flap (WMF) and enamel matrix derivative (EMD). METHOD: 30 patients with an infrabony component > or = 4 mm were selected. 10 were treated with expanded polytetrafluorethylene (ePTFE (Gore - Tex W. L. Gore and Associates, Flagstaff, AZ, USA)) membranes, 10 with WMF and 10 with enamel matrix derivatives (Emdogain (U Biora AB Malm, Sweden)). The efficacy of each treatment modality was investigated through regression analysis. Probing attachment level (PAL) gain, probing depth (PD) reduction and gingival recession (REC) variation were analyzed. RESULTS: Both Emdogain (enamel matrix derivative) and ePTFE treatment show significant better results as compared to the WMF procedure in which there were no significant changes in PAL gain and PD reduction at baseline and 1 year after surgery. CONCLUSIONS: Results from our analysis suggest that there is no statistically significant difference in PAL gain between GTR and EMD. The clinical outcomes of this pilot study may be of little significance, considering the small number of patients, but it has provided an important base for a controlled clinical trial (with a larger number of patients) which is currently in progress.

Clinical and histologic evaluation of human gingival recession treated with a subepithelial connective tissue graft and enamel matrix derivative (Emdogain): a case report.

A mandibular canine with significant gingival recession was selected for a pilot study to measure the attachment modalities resulting from mucogingival surgery. The tooth had 6 mm of recession as measured from the cementoenamel junction to the gingival margin, minimal pocketing, and no keratinized gingiva. The treatment regimen consisted of a subepithelial connective tissue graft (SCTG) plus Emdogain applied to the root surface. The tooth was extracted en bloc 6 months after surgery and processed histologically in a buccolingual plane. The tooth demonstrated a 2-mm gain of attachment and a 3-mm gain in keratinized tissue. The histologic study evidenced the migration of the junctional epithelium 1.2 mm apical to the sulcus. New cementum, evidence of newly formed woven bone, and connective tissue fibers anchored in the new cementum were evident.

Histomorphometric analysis of a half hydroxyapatite-coated implant in humans: a pilot study.

The aim of this study was to compare the characteristics of the bone-to-implant interface of hydroxyapatite-coated and non-coated commercially pure titanium threaded implants after different periods of healing in humans. To eliminate possible variations of the results from differences in bone quality and in surgical techniques used in the different test and control sites, only one half of each implant was coated with hydroxyapatite. The coated portions of the implants showed a tendency toward a higher percentage of direct bone-to-implant contact at each period of healing that was observed, although the small number of specimens does not allow definitive conclusions to be made.

Surgical technique for treatment of infrabony defects with enamel matrix derivative (Emdogain): 3 case reports.

A surgical protocol is described for the placement of Emdogain enamel matrix derivative during new attachment procedures. Three cases with infrabony defects were treated and a significant probing attachment level (PAL) gain, probing depth reduction, and bone fill were evident on clinical probing and during reentry procedures. The first patient presented a combined one-walled and circumferential defect at a maxillary central incisor. After 1 year the PAL gain was 7 mm. The second case showed a 3-walled defect distal to a maxillary canine. After 1 year the PAL gain was 8 mm, and a reentry procedure showed an almost total fill of the defect. The third patient presented a combined one- and 3-walled defect in the most apical part of the mesial aspect of a maxillary central incisor. One year after the surgical procedure, an orthodontic treatment was performed in this patient. After 6 more months the soft tissue showed a very good esthetic appearance, the papilla height was fully maintained, and there was a PAL gain of 5 mm; 18 months after surgery, reentry showed a significant regeneration of hard tissue that was impossible to probe. Because of these encouraging clinical results, further studies should be initiated to investigate the efficacy of the enamel matrix derivative in new attachment procedures.

In vivo early plaque formation on pure titanium and ceramic abutments: a comparative microbiological and SEM analysis.

A lack of information exists about the influence of different implant abutment materials on bacterial colonization and its role in the development of perimplantar infections. In order to study these aspects, removable acrylic devices, harboring samples of titanium and novel ceramic abutments (Nobel Biocare) were adapted to the molar-premolar region in 2 mandibular quadrants of 4 volunteers. Samples of each material were collected at 6 and 24 h, 7 and 14 days. Samples were observed by scanning electron microscopy and bacterial counts were made by means of ATP detection and direct plate count. The electron micrographs demonstrated that the bacteria colonization was already present after 6 h of presence in the oral cavity. After 24 h, both the materials were covered by several layers of bacterial cells. No differences in microbial colonization were observed between titanium and ceramic samples. The microbiological analysis confirmed the presence of relevant amounts of microbial cells on the tested samples. The maximum of colonization was achieved after 24 h in the oral cavity and the bacterial counts remained constant over the 14 day period. No significant differences were observed between the two materials analyzed in this study. In addition, ATP-bioluminescence technology was demonstrated to be a suitable system to evaluate bacterial colonization in the oral cavity.

Clinical, radiographic, and histologic evaluation of human periodontal defects treated with Bio-Oss and Bio-Gide.

This study evaluated the clinical, radiographic, and histologic response to Bio-Oss porous bone mineral when used alone or in combination with Bio-Gide bilayer collagen membrane in human periodontal defects. Four intrabony periodontal defects were treated: two received Bio-Oss alone and two were treated with a combination of Bio-Oss and Bio-Gide. Radiographs, clinical probing depths and attachment levels were obtained preoperatively and 6 to 9 months postoperative, and teeth and surrounding tissues were biopsied. Both treatments significantly improved clinical probing depths and attachment levels, and the radiographic appearance suggested osseous fill. Histologic evaluation revealed that both treatments produced new cementum with inserting collagen fibers and new bone formation on the surface of the graft particles; this regenerative effect was more pronounced using the Bio-Oss/Bio-Gide combination, which resulted in 7 mm of new cementum and periodontal ligament and extensive new bone incorporating the graft. The membrane was intact at 7 months and partially degraded by 9 months after treatment. This human histologic study demonstrates that the porous bone mineral matrix used has the capacity to stimulate substantial new bone and cementum formation and that this capacity is further increased when the graft is used with a slowly resorbing collagen membrane.

A clinical/statistical comparison between the subpedicle connective tissue graft method and the guided tissue regeneration technique in root coverage.

Subepithelial connective tissue grafts and guided tissue regeneration have been shown to be effective means to obtain root coverage. The purpose of this study is to compare statistically the results obtained with these techniques 1 year after the surgical procedures were performed. Thirty-six gingival recessions belonging to Class I and Class II of the Miller classification were treated: 18 cases with subepithelial connective tissue grafts (SCTG) and 18 cases with guided tissue regeneration (GTR). Each patient was randomly assigned to a group. At baseline, the group treated with subepithelial connective tissue grafts presented a mean recession of 4.88 mm, whereas the group treated with guided tissue regeneration presented a mean recession of 5.88 mm (P = .082). After 1 year, the mean root coverage was 77.08% in the SCTG group and 80.88% in the GTR group. The difference was not statistically significant (P > .05). The mean root coverage was 3.83 mm for the SCTG group and 4.61 mm for the GTR group. The mean gain in probing attachment level was 3.05 mm for the SCTG group and 5.55 mm for the GTR group. The difference was statistically significant (P = .01). In conclusion, the mean root coverage obtained was similar for the two groups, whereas the clinical attachment gain was greater in the GTR group. Therefore, it appears that the GTR technique is preferable when severe mucogingival defects are present and gain of clinical attachment level is mandatory.

In vitro permeability evaluation and colonization of membranes for periodontal regeneration by Porphyromonas gingivalis.

The use of membranes for periodontal regeneration is well established. In clinical use, the exposure of membranes to the oral microflora may result in a pathway for periodontal infections. An important role in this process is played by Porphyromonas gingivalis. The purpose of the present study was to examine the colonization of 6 different bioresorbable and nonresorbable membranes for periodontal regeneration by the strain DSM 20709 of P. gingivalis and to determine the time needed by this microorganism to pass through the membranes. A device consisting of a tube sealed with the membranes and filled with a medium suitable for the growth of P. gingivalis was incubated in a bigger tube containing the same medium to study the process of colonization and the crossing of membranes. The outer tube was inoculated with 10(4) cells of P. gingivalis DSM 20709. The passage of bacteria through the membranes was monitored at 6, 24, and 48 hours by counting the number of cells in the inner tube. The colonized membranes were observed using a scanning electron microscope. Differences in the behavior of the 6 membranes analyzed were demonstrated.

Surgical reinstatement of aesthetics in the maxillary anterior region: a case report.

The maxillary anterior region is frequently treated for aesthetic enhancement. This article presents the case of a patient who had undergone surgery for treatment of a tumor of the hypophysis involving intraoral access to the sella turcica. The treatment had caused the formation of severe gingival recession on the buccal surface of the maxillary anterior teeth. A variety of surgical techniques were considered for covering the exposed root surfaces. The surgical site was analyzed, and the response of the periodontal tissue to the treatment was anticipated. The bilaminar method, utilizing a subpedicle connective tissue graft (SCTG), was selected. The learning objective of this case presentation is to demonstrate that when the appropriate treatment procedure is selected, restoration of function and aesthetics can be achieved even in the most advanced cases.