Search

Howard H Wang, 1 Hsi-Ming Lee, 2 Veena Raja, 2 Wei Hou, 3 Vincent J Iacono, 4 Joseph Scaduto, 5 Francis Johnson, 6,7 Lorne M Golub, 2 Ying Gu 8 1Department of Periodontology and Endodontology, School of Dental Medicine, State University of New York at Buffalo, Buffalo, NY, USA; 2Department of Oral Biology and Pathology, School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA; 3Department of Preventive Medicine, School of Medicine, Stony Brook University, Stony Brook, NY, USA; 4Department of Periodontology, School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA; 5Traverse Biosciences Inc., Stony Brook, NY, USA; 6Department of Chemistry, Stony Brook University, Stony Brook, NY, USA; 7Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, USA; 8Department of General Dentistry, School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA Introduction: Dental microbial biofilm initiates gingival inflammation, and its suppression is the current dominant strategy for treating periodontitis. However, the host response to the biofilm is largely responsible for the connective tissue breakdown including alveolar bone loss, which is mediated by proinflammatory cytokines and matrix metalloproteinases (MMPs). Methods: The current study compared the efficacy of a novel host-modulation compound, a chemically modified curcumin (CMC 2.24), to that of its parent compound (natural curcumin), in both lipopolysaccharide (LPS) (a bacterial endotoxin)-induced cell culture and in vivo models of periodontitis. Results: In cell culture, both CMC 2.24 and curcumin appeared similarly effective in suppressing LPS-induced cytokine (IL-1β and TNF-α) secretion by mononuclear inflammatory cells; however, CMC 2.24 significantly reduced MMP-9 secretion by 78% (P< 0.05) whereas curcumin was ineffective. In vivo, CMC 2.24 administration was more effective than curcumin in suppressing (a) IL-1β in gingival tissue and (b) MMP-9 in both gingiva and plasma, the latter indicating a reduced severity of systemic inflammation. The difference in primary clinical outcome between the two treatments was that CMC 2.24 reduced the pathologically excessive alveolar bone loss, assessed morphometrically at multiple sites, by 80%– 90% (P< 0.01), whereas curcumin, surprisingly, either increased (P< 0.05) or had no effect on alveolar bone loss at these sites. Conclusion: These data, plus that from previous studies, support the therapeutic potential of CMC 2.24 in the management of inflammatory periodontal disease and its ability to reduce the risk of associated systemic diseases. The current study also indicates that the MMP-9 inhibitor efficacy is associated with the ability of CMC 2.24 (but not curcumin) to inhibit alveolar bone loss in this rat model of periodontitis. Keywords: chemically modified curcumin, cytokines, matrix metalloproteinases, MMPs, periodontitis, ratsCorrigendum for this paper has been published

Wang HH, Lee HM, Raja V, et al. J Exp Pharmacol. 2019;11:1–14.On page 13 the disclosure section should be presented as follows:DisclosureLMG is listed as an inventor on several related patents and these have been fully assigned to his institution, Stony Brook University, The State University of New York (SUNY). FJ is also listed as an inventor on several related patents which have been fully assigned to Stony Brook University and to Chem-Master Int. Inc. on a shared basis. In addition, both LMG and FJ are minor shareholders in Traverse BioSciences, Inc., and JS is president and major shareholder in Traverse. All other authors declare that there are no conflicts of interest regarding the publication of this paper.Read the original article

The risk of developing osteochemonecrosis is increased in patients who are taking bisphosphonate drugs and must undergo extractions or other dental surgery. Because of the difficulty in predicting and preventing osteochemonecrosis and in managing patients after it has occurred, avoidance of surgery has been advised. This paper reports on the development of this complication in a patient who received nonsurgical periodontal treatment. Although it is believed that the risk of developing this severely debilitating complication is low when treating patients nonsurgically, practitioners must be able to recognize and understand the presentation and difficulties in managing osteochemonecrosis, even when only nonsurgical therapy is performed. [ABSTRACT FROM AUTHOR]

Purpose: To compare the clinical outcomes of metal-ceramic vs metal-acrylic resin implant-supported fixed complete denture prostheses (IFCDPs)., Materials and Methods: An electronic literature database search was conducted in the CINAHL, EMBASE, PubMed, and Web of Science databases. Additionally, a manual search of the literature was performed. Studies conducted in edentulous human subjects comparing clinical outcomes of metal-acrylic resin IFCDPs to those of metal-ceramic IFCDPs were included if quantitative outcomes for the following variables were reported: implant failure, prosthetic failure, incidence of peri-implantitis, incidence of peri-implant mucositis, incidence of peri-implant mucosal recession, prosthetic complications, and any patient-centered outcomes. Data from included studies were pooled to estimate effect size., Results: Five studies met the inclusion criteria. A quantitative analysis was possible for risk of implant failure, prosthesis failure, and incidence of peri-implantitis. Meta-analysis showed no statistically significant differences in the risk of implant or prosthesis failure between the two groups. However, meta-analysis showed a significantly greater risk of developing peri-implantitis at the implant level in the metal-acrylic group when compared to the metal-ceramic group (risk difference = 0.069; 95% CI = 0.028 to 0.06; P = .001; fixed-effects model). Furthermore, descriptive analysis of the literature indicated a higher incidence of other biologic complications such as peri-implant mucositis and peri-implant mucosal recession, as well as prosthetic complications such as abrasion and veneer fracture, in metal-acrylic resin IFCDPs compared to metal-ceramic IFCDPs., Conclusion: The available evidence suggests that a higher incidence of biologic and prosthetic complications, including a higher risk of peri-implantitis, are present with metal-acrylic resin IFCDPs compared to metal-ceramic IFCDPs.

Objective: Peri-implantitis has been attributed to a myriad of factors, including microleakage at the abutment-implant interface. Implant abutment access channel sealing materials (IACSM) are readily used in implant dentistry, with little evidence on their effect on microleakage. This study aims to evaluate the effect of IACSM on the microbial composition in the implant access channel and the peri-implant sulcus., Methods: A total of n = 8 patients (64 implants) were included in this single-blinded, randomized controlled trial, whereas four different materials (cotton, polytetrafluoroethylene [PTFE], synthetic foam, or polyvinyl siloxane [PVS]) were randomly placed as an IACSM. Following 6 months, microbial analysis was completed on the IACSM and samples from the peri-implant sulci via PCR and high-throughput sequencing. Bacterial samples on the IACSM and in the peri-implant sulci were classified according to Socransky's microbial complexes., Results: There was a preponderance of early colonizing bacteria within the IACSM, while the peri-implant sulci were dominated by Orange complex bacteria. The proportion of Red and Orange complex members on the IACSM was significantly less than in the peri-implant sulci. The proportion of Green, Yellow, and Blue complex members found on the IACSM was significantly greater than in the peri-implant sulci. Atopobium, a diverse species not included in the microbial complexes, was frequently detected in the peri-implant sulcus samples., Conclusions: No detectable effects of IACSM on the microbial community in the peri-implant sulcus or on the IACSM were identified. Variation of bacterial species was most dependent on the individual patient. No significant differences were found in the periodontal parameters between the different treatment groups., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Perforated barrier membranes (PBM) were suggested to enhance periodontal regeneration by allowing positive charity of wanted elements from the gingival tissue side. The present study was designed to evaluate clinically and biochemically the use of PBM combined with simvastatin (SMV) gel with and without an associated EDTA gel root surface etching as a suggested option that could improve SMV availability and clinical outcomes of PBM., Methods: Forty patients having moderate-to-severe chronic periodontitis with 40 intrabony defects were randomly divided into four treatment groups (10 sites each). Patients in group 1 received 1.2% SMV gel and covering the defect with occlusive membrane (OM). Patients in group 2 received 1.2% SMV gel and covering the defect with PBM. Group 3 received 24% EDTA root surface etching, 1.2% SMV gel, and defect coverage with OM (eOM). Patients in group 4 were treated as in group 3 but the defect was covered with PBM (ePBM). Clinical parameters were recorded at baseline before surgical procedures and were reassessed at 6 and 9 months after therapy. The mean concentration of SMV in gingival crevicular fluid (GCF) was estimated by reverse-phase high-performance liquid chromatography at days 1, 7, 14, 21, and 30., Results: At 6- and 9-month observation periods, groups 3 and 4 showed a statistically significant improvement in PD reduction and CAL gain compared with groups 1 and 2. Group 4 showed a statistically significant more defect fill compared with groups 1, 2, and 3 (P ≤ .05). Group 2 showed statistically significant higher defect fill compared with group 1 and group 3 (P < .05). Bone density was significantly increased with no significant difference between the four groups at 6- and 9-month observation periods. SMV-GCF concentration in group 4 showed the highest mean concentration with no significant difference than that of group 3., Conclusion: The use of perforated barrier membranes in association with SMV enhances the clinical hard tissue parameters compared with occlusive ones in treating intrabony periodontal defects. Moreover, EDTA root surface treatment could enhance SMV availability in the defect area., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The aim of this review was to determine the most common peri-implant mucositis and peri-implantitis case definitions used worldwide in the implant dentistry literature. A systematic assessment of peri-implant disease classification was conducted using all publications in MEDLINE, EMBASE, SCOPUS, and Google Scholar between 1994 and November 2017. Screening of eligible studies and data extraction were conducted in duplicate and independently by 2 reviewers. The search protocol identified 3049 unique articles, of which 2784 were excluded based on title and abstract. In total, 265 full texts were screened, 106 of which met the eligibility criteria. Of these, 41 defined peri-implant mucositis. Eight (19.6%) used bleeding on probing (BOP) only; 8 (19.6.7%) used a combination of probing depth (PD), BOP, and radiograph; and 5 (12.3%) used PD and BOP. Cases with crestal bone loss of ≤2 mm in the first year and ≤0.2 mm in each subsequent year were considered as peri-implant mucositis. Ninety-three articles defined peri-implantitis; 28 (30.1%) used a combination of PD with suppuration, BOP, and radiograph, followed by 25 (26.9%) using a combination of PD, BOP, and radiograph. The main criteria in most of the studies were considered to be BOP, PD, and radiograph. Cases of crestal bone loss of ≥2 mm and PD ≥3 mm are considered peri-implantitis. Different peri-implant disease case definitions may affect disease prevalence and treatment strategies. We need to standardize case definitions to avoid discrepancies in case diagnosis and prognosis.

Purpose: To evaluate the biochemical composition of bone nodules deposited by gingival mesenchymal stem cells (GMSCs) over titanium machined surfaces in vitro., Materials and Methods: GMSCs were isolated from healthy gingival tissues of patients undergoing crown-lengthening surgical procedures. GMSCs were characterized following the International Society for Cellular Therapy guidelines. After incubation of the GMSCs with titanium discs, osteogenic differentiation was induced for 28 days. Osteogenic lineage was confirmed by means of Alizarin Red S staining. Bone nodule morphology and deposition by GMSCs were characterized by scanning electron microscopy (SEM). An elemental analysis of the bone nodules was done using energy-dispersive x-ray spectroscopy (EDS). The biochemical composition of these nodules was further characterized via Raman spectroscopy, with native alveolar bone used as a control., Results: GMSCs adhered and proliferated on the titanium discs and exhibited a spindle-shaped fibroblast-like morphology under standard culture conditions. Their phenotype was confirmed by the expression of CD105, CD90, CD73, and CD146, observed using flow cytometry. Deposits of calcium bone nodules were evident in the cultures after staining with Alizarin Red S, but were absent in the controls. Calcium and phosphate, the major components of hydroxyapatite, were present in the bone nodules, as shown by means of the EDS analysis. The results obtained from Raman spectra of these nodules showed the phosphate ions (ν[PO₄³⁻], ~960 cm¹), amide III (δ[NH], ~1,245 cm⁻¹), CH₂ scissors (~1,451 cm⁻¹), amide I (ν[C = O], ~1,667 cm⁻¹), and ν(CH) (2,800-3,100 cm⁻¹) bands were similar to those observed in native bone., Conclusion: GMSCs can deposit a bone-like mineral highly similar to native bone (HA) over titanium surfaces. Ongoing studies are aimed at determining whether GMSCs can deposit a similar bone matrix/tissue over removed failed dental implants. If HA can be placed over removed failed dental implants, it may be possible to re-osseointegrate dental implants that are failing as a result of peri-implantitis in vivo.

Background: Migration of gingival fibroblasts/gingival mesenchymal stem cells through macro-perforated barrier membranes may allow them to participate positively in periodontal regeneration. The optimal guided tissue membrane perforation diameter that could favor maximum cell migration into the defect area and at the same time act as an occlusive barrier for gingival epithelium and its associated gingival extracellular matrix component is not yet identified., Material and Methods: Cultured human gingival fibroblasts/gingival mesenchymal stem cells were placed in the upper chambers of 12-well collagen-coated polytetrafluoroethylene transwells, which were manually perforated with 0.2, 0.4 and 0.7 mm sized pores. The lower chambers of the transwells received blood clot as an attraction medium. The number of cells that have migrated to the lower chambers was calculated. Proliferation of these cells was evaluated using MTT assay. Scanning electron microscopy images were obtained for the lower surfaces of the transwell membranes. Perforated bovine collagen membranes (Tutopatch ® ) were subjected to mechanical testing to determine the tensile strength and modulus of elasticity., Results: Group 3 (0.7 mm) showed significantly higher values for cell migration and proliferation. All groups showed a small degree of extracellular matrix migration through membrane perforations. Scanning electron microscopy evaluation revealed variable numbers of cells in fibrin matrices located mainly around the pore edges. There were non-significant differences between groups regarding mechanical properties., Conclusions: The present study demonstrated that macro-membrane perforations of 0.2, 0.4 and 0.7 mm are suitable pore diameters that could maintain membrane stiffness and allow for cellular migration. However, these membrane perforation diameters did not allow for total gingival connective tissue isolation., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Although retrograde peri-implantitis (RPI) is not a common sequela of dental implant surgery, its prevalence has been reported in the literature to be 0.26%. Incidence of RPI is reported to increase to 7.8% when teeth adjacent to the implant site have a previous history of root canal therapy, and it is correlated with distance between implant and adjacent tooth and/or with time from endodontic treatment of adjacent tooth to implant placement. Minimum 2 mm space between implant and adjacent tooth is needed to decrease incidence of apical RPI, with minimum 4 weeks between completion of endodontic treatment and actual implant placement. The purpose of this study is to compile all available treatment modalities and to provide a decision tree as a general guide for clinicians to aid in diagnosis and treatment of RPI., Methods: Literature search was performed for articles published in English on the topic of RPI. Articles selected were case reports with study populations ranging from 1 to 32 patients. Any case report or clinical trial that attempted to treat or rescue an implant diagnosed with RPI was included., Results: Predominant diagnostic presentation of a lesion was presence of sinus tract at buccal or facial abscess of apical portion of implant, and subsequent periapical radiographs taken demonstrated a radiolucent lesion. On the basis of case reports analyzed, RPI was diagnosed between 1 week and 4 years after implant placement. Twelve of 20 studies reported that RPI lesions were diagnosed within 6 months after implant placement. A step-by-step decision tree is provided to allow clinicians to triage and properly manage cases of RPI on the basis of recommendations and successful treatments provided in analyzed case reports. It is divided between symptomatic and asymptomatic implants and adjacent teeth with vital and necrotic pulps., Conclusions: Most common etiology of apical RPI is endodontic infection from neighboring teeth, which was diagnosed within 6 months after implant placement. Most common findings, radiographically and clinically, are lesions around implant apex and sinus tract. A small number of implants did not improve with treatment. Decision tree provides a path to diagnose and treat lesions to facilitate their management. Further studies are needed to focus on histologic data around periapical microbiota to establish specific etiology and differential diagnoses compared with marginal peri-implantitis and other implant-related conditions.

Background and Objective: Perforated barrier membranes open channels between the suprabony and intrabony compartments of the defect, which could allow for more physiologic cellular interactions between different components of the periodontium during guided tissue regeneration surgery. To test this assumption, this study was designed to evaluate levels of vascular endothelial cell growth factor (VEGF) and platelet-derived growth factor (PDGF)-BB in gingival crevicular fluid during the early stages of healing of localized intrabony defects treated with perforated membranes (PMs) or non-PMs, as compared with open flap debridement., Material and Methods: Thirty non-smoking patients with severe chronic periodontitis participated in this prospective, randomized and single blinded trial. Each patient contributed one interproximal defect that was randomly assigned to the PM group (n = 10), occlusive membrane (OM) group (n = 10) or open flap debridement (OFD) group (n = 10). Plaque index, gingival index, probing depth, clinical attachment level and the intrabony depth of the defect were measured at baseline and reassessed at 6 and 9 mo after therapy. Gingival crevicular fluid samples were collected on days 1, 3, 7, 14, 21 and 30 d after therapy for the changes in VEGF and PDGF-BB levels., Results: During the early stages of healing (1, 3 and 7 d), the mean VEGF and PDGF-BB concentrations at sites treated with PMs and OFD peaked with a statistically significant difference as compared with the OM-treated group. VEGF and PDGF-BB levels at sites treated with PMs and OFD were not statistically different. Growth factor levels decreased sharply in the samples obtained at days 21 and 30 with non-significant differences between the three groups. Nine months after therapy, the PM-treated group showed a statistically significant improvement in probing depth, clinical attachment level and intrabony defect compared to the OM and OFD groups., Conclusions: Within the limits of the present study, one can conclude that PM coverage of periodontal defects is associated with initial gingival crevicular fluid growth factor upregulation that could improve the clinical outcomes of guided tissue regeneration surgery., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: Multiple bone augmentation techniques are available to allow implant placement in the atrophic maxilla. However, questions remain, regarding which methods are most predictable and have the best dental implant survival rate (SR) in grafted bone. The aim of this systematic review was to evaluate literature from the last 30 years to determine predictability of bone grafting of the edentulous maxilla for implant placement as well as for implant SR., Materials and Methods: A systematic review was performed of studies conducted during the period 1980 to 2014, specifically focusing on the edentulous maxilla and bone grafting. Surgical techniques discussed in the publications included were guided bone regeneration (GBR), sinus augmentation, onlay bone grafting, nasal floor grafting, and Le Fort I interpositional grafting. All identified articles were evaluated and screened to meet strict inclusion criteria of at least 10 patients, complete maxillary edentulism, 1-year follow-up, and information regarding implant SR. A total of 974 articles were identified with electronic and manual searches. On further evaluation of the titles and abstracts, 44 articles were excluded. Full texts of the articles that met the inclusion criteria were reviewed, of which 40 articles were included in the systematic review., Results: For onlay bone grafting, 16 studies were included and analyzed, and the weighted mean implant SR was 85.2%. For the GBR technique, two studies were included, with a reported SR ranging from 96.1% to 100%. For Le Fort I interpositional grafting, 11 studies were included, with a weighted mean SR of 89.6%. For the sinus augmentation technique, 12 studies were investigated and the weighted mean SR was 91.5%. For the combination technique, six studies were analyzed and the weighted mean SR was 93.6%., Conclusions: All five treatment modalities discussed-onlay bone grafting, GBR, Le Fort I interpositional grafting, maxillary sinus augmentation, and/or nasal floor inlay grafting or the combination approach-can be successfully used to augment edentulous maxillary ridge with high implant SRs.

Background: In guided tissue regenerative surgery, membrane perforations may serve as a mechanism for the passage of cells and biologic mediators from the periosteum and overlying gingival connective tissue into the periodontal defects. To test this assumption, this study was designed to evaluate levels of bone morphogenetic protein-2 (BMP-2) in gingival crevicular fluid (GCF) during the early stages of healing for sites treated with modified perforated membranes (MPMs) as compared with occlusive membranes (OMs)., Methods: Fifteen non-smoking patients with severe chronic periodontitis participated in this prospective, randomized and single-blinded clinical trial. Each patient contributed two interproximal contralateral defects that were randomly assigned to either an experimental modified perforated membrane group (15 sites) or a control occlusive membrane group (15 sites). Plaque index, gingival index, probing depth(PD), clinical attachment level (CAL) and the relative intrabony depth of the defect (rIBD) were measured at baseline and reassessed at three, six and nine months after therapy. Gingival crevicular fluid samples were collected on day 1 and 3, 7, 14, 21, and 30 days after therapy., Results: The MPM-treated group showed a statistically significant improvement in PD reduction and clinical attachment gain compared to the OM control group. Similarly, rIBD was significantly reduced in MPM-treated sites as compared with those of the OM group. BMP-2 concentrations peaked in the MPM samples obtained during the early postoperative period (days 1, 3 and 7) with a statistically significant difference compared with OM-treated groups. BMP-2 levels decreased sharply in the samples obtained at days 14, 21 and 30 with non-significant higher levels in MPM samples as compared with those of OM sites., Conclusion: Within the limits of the present study, one can conclude that MPM coverage of periodontal defects is associated with a significant initial increase in GCF levels of BMP-2, a factor that could improve the clinical outcomes of guided tissue regenerative surgery.

Background: The use of nanoparticles of graft materials may lead to breakthrough applications for periodontal regeneration. However, due to their small particle size, nanoparticles may be eliminated from periodontal defects by phagocytosis. In an attempt to improve nanoparticle retention in periodontal defects, the present in vivo study uses scanning electron microscopy (SEM) to evaluate the potential of micrograft particles of β-tricalcium phosphate (β-TCP) to enhance the binding and retention of nanoparticles of hydroxyapatite (nHA) on EDTA-treated and non-treated root surfaces in periodontal defects after 14 days of healing., Methods: Sixty patients having at least two hopeless periodontally affected teeth designated for extraction were randomly divided into four treatment groups (15 patients per group). Patients in group 1 had selected periodontal intrabony defects grafted with nHA of particle size 10 to 100 nm. Patients in group 2 were treated in a similar manner but had the affected roots etched for 2 minutes with a neutral 24% EDTA gel before grafting of the associated vertical defects with nHA. Patients in group 3 had the selected intrabony defects grafted with a composite graft consisting of equal volumes of nHA and β-TCP (particle size 63 to 150 nm). Patients in group 4 were treated as in group 3 but the affected roots were etched with neutral 24% EDTA as in group 2. For each of the four groups, one tooth was extracted immediately, and the second tooth was extracted after 14 days of healing for SEM evaluation., Results: Fourteen days after surgery, all group 1 samples were devoid of any nanoparticles adherent to the root surfaces. Group 2 showed root surface areas 44.7% covered by a single layer of clot-blended grafted particles 14 days following graft application. After 14 days, group 3 samples appeared to retain fibrin strands devoid of grafted particles. Immediately extracted root samples of group 4 had adherent graft particles that covered a considerable area of the root surfaces (88.6%). Grafted particles appeared to cover all samples in a multilayered pattern. After 14 days, the group 4 extracted samples showed multilayered fibrin-covered nano/micro-sized graft particles adherent to the root surfaces (78.5%)., Conclusion: The use of a composite graft consisting of nHA and microsized β-TCP after root surface treatment with 24% EDTA may be a suitable method to improve nHA retention in periodontal defects with subsequent graft bioreactivity.

Background: The present study was designed to determine whether exclusion of the gingival connective tissue (CT) and periosteum with contained stem cells has a positive or negative effect on periodontal regeneration by comparing the use of a novel modified perforated collagen membrane with a traditional cell occlusive barrier membrane., Methods: Twenty non-smoking patients with severe chronic periodontitis were included in the study. Single deep intrabony defects from each of the patients were randomly divided into two groups, as follows: occlusive bovine collagen membranes (OM control group, 10 sites) and modified perforated bovine collagen membranes (MPM test group, 10 sites). Plaque index, gingival index, probing depth (PD), clinical attachment level (CAL), defect base level (DBL), and crestal bone level (CBL) were measured at baseline and were reassessed at 6 and 9 months after therapy to evaluate the quantitative changes in the defect., Results: At 6- and 9-month observation periods, the MPM-treated sites showed a statistically significant improvement in PD reduction and CAL gain compared with the OM control group. DBL was significantly reduced with no significant difference between the two groups at 6- and 9-month observation periods. CBL was significantly higher in the MPM group when compared with that of the OM group at both observation periods. The postoperative differences between the two groups were 2 and 1.7 mm at 6 and 9 months, respectively, in favor of the MPM-treated sites., Conclusions: The present study demonstrated enhanced clinical outcomes when using novel MPMs compared to OMs in guided tissue regeneration procedures. These results may be affected by the penetration of gingival CT contained stem cells and periosteal cells and their differentiation into components of the attachment apparatus.

Purpose: This overview was prepared to describe how an evidence-based approach was used to develop an Academy of Osseointegration (AO) Workshop on the State of the Science on Implant Dentistry (SSID)., Materials and Methods: An AO SSID Workshop Planning Committee was appointed in 2001 to follow an evidence-based approach for reviewing published clinical data using strict inclusion and exclusion criteria in order to answer 8 closed-end 4-part clinical questions. A systematic approach was employed to assure coherent data management and analysis. Reviewers, co-reviewers, and a biostatistician were appointed. The workshop agenda was developed to include participants who had the primary responsibility for each of the 8 workshop sections to answer 5 consensus questions for the section's systematic review. The planned outcomes of the SSID Workshop included publication of the 8 consensus reports with their respective systematic reviews in The International Journal of Oral & Maxillofacial Implants (supplemental issue), 2007; the development of clinical guidelines responding to each of the 8 focused questions; and the identification and prioritization of questions or topics requiring further research., Results: The evidence-based approach was utilized successfully in planning and carrying out the AO SSID Workshop held on August 3-6, 2006, in Oak Brook, Illinois, and the subsequent publication of its proceedings., Discussion: Although successful in its objectives, the outcome of systematic reviews is only as good as the published data. Significant deficiencies in published implant studies were identified, including, but not limited to, a lack of randomized controlled prospective clinical trials, universal acceptance and publication of defined implant survival and success criteria, and clear questions with well-defined research design., Conclusion: The evidence-based approach can be used to systematically review the literature for a workshop on important questions related to implant dentistry. A major limitation is the lack of common outcome variables between published studies.

Background: Enamel matrix derivative (EMD) is used during periodontal surgery for the regeneration of periodontal tissue. It consists of the amelogenin fraction of porcine enamel matrix (AMEL) suspended in a vehicle of propylene glycol alginate (PGA). EMD-treated sites appear to heal with less inflammation. It has been suggested that antimicrobial properties of EMD might account for improved healing in vivo. The objectives of this study were: 1) to determine the antibacterial effects of EMD on the periodontal pathogen Porphyromonas gingivalis and 2) to establish the component(s) of EMD that are responsible for this effect., Methods: The antimicrobial effects were determined in vitro using the broth dilution assay. P. gingivalis at a starting inoculum of 10(9) colony forming units/ml was treated with EMD, AMEL, and PGA in Hank's balanced salt solution (HBSS) for 1, 3, and 24 hours. The CFU/ml of P. gingivalis recovered on enriched Brucella blood agar was determined at 6 and 10 days., Results: EMD (containing AMEL and PGA) or PGA alone eliminated recoverable CFUs of P. gingivalis. Interestingly, AMEL in HBSS increased recoverable CFUs from 8.62 log CFU/ml to 8.93 log CFU/ml. Further analysis of the dose response at concentrations of 0.3, 3, and 30 mg/ml of AMEL in HBSS revealed that only 30 mg/ml (clinical concentration) increased CFUs of P. gingivalis relative to baseline (from 8.8 log CFU/ml to 9.2 log CFU/ml in 3 hours). Additionally, AMEL was compared to a protein control bovine serum albumin (BSA) to determine whether this effect was unique to AMEL. A marked increase in recoverable CFUs occurred with the AMEL (increasing from 8.8 log CFU/ml to 9.47 log CFU/ml), but not with BSA., Conclusions: EMD possesses antimicrobial properties that can be attributed to the propylene glycol alginate vehicle. The amelogenin fraction of porcine enamel matrix in enamel matrix derivative (i.e., AMEL) is not antibacterial for P. gingivalis and was shown to increase recoverable CFUs.

Background: Gingival crevicular fluid (GCF) biomarkers associated with bone resorption may be useful to determine periodontal disease status and response to therapy. The pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), a bone-specific degradation product, and interleukin 1-beta (IL-1), a potent bone-resorptive cytokine, have both been associated with periodontal disease activity. Minocycline is a tetracycline derivative possessing antimicrobial effects on periodontal pathogens and inhibitory properties on matrix metalloproteinases (MMPs) associated with tissue destruction. The aim of this study was to evaluate the effect of periodontal treatment in the form of scaling and root planing (SRP) and locally administered minocycline microspheres on the GCF levels of ICTP and IL-1., Methods: Forty-eight chronic periodontitis patients were randomly assigned to 2 groups (SRP plus subgingival application of vehicle control [SRP + V], or SRP plus subgingival application of minocycline microspheres [SRP + M]) and monitored at 8 sites per subject at baseline and 1, 3, and 6 months. Four shallow (PD < or = 3 mm) and 4 deep (PD > or = 5 mm) sites were evaluated for both marker levels and for probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). Eight periodontally healthy control subjects with no probing depths >3 mm and no loss of attachment were also monitored at the same time intervals. GCF levels of ICTP and IL-1 were determined using radioimmunoassay and enzyme-linked immunosorbent assay techniques, respectively., Results: Significant differences (P<0.001) in GCF levels of ICTP and IL-1 were found between deep and shallow sites at all time points in both treatment groups. In addition, healthy subjects demonstrated significantly reduced levels of both markers compared to both shallow and deep sites in periodontitis patients (P <0.001). Only the SRP + M treated patients exhibited significant reductions (P <0.05) in both ICTP and IL-1 levels 1 month after treatment. Furthermore, the SRP + M group demonstrated significantly lower IL-1 levels (P <0.02) at 1 month compared to the SRP + V group., Conclusions: Results of this study indicate that GCF levels of ICTP and IL-1 correlate with clinical measures of periodontal disease and may aid in assessing disease status and response to periodontal therapy. Furthermore, local administration of minocycline microspheres led to a potent short-term reduction in GCF IL-1 levels. Additional studies are needed to address whether repeated administration of scaling and root planing along with minocycline microspheres will achieve long-term reductions in GCF ICTP and IL-1 levels.

Background: Biochemical markers harvested from gingival crevicular fluid (GCF) may be useful to identify and predict periodontal disease progression and to monitor the response to treatment. C-telopeptide pyridinoline cross-links (ICTP), a host-derived breakdown product specific for bone, and interleukin-1beta (IL-1), a potent bone-resorptive cytokine, have been associated with periodontal tissue destruction. The aim of this study was to examine the effect of non-surgical periodontal therapy on GCF levels of ICTP and IL-1., Methods: Twenty-five chronic periodontitis subjects were monitored at 8 sites per subject at baseline prior to scaling and root planing and 1, 3, and 6 months after therapy. Four shallow (probing depths < 4 mm) and 4 deep (probing depths > or = 5 mm) sites were monitored for both marker levels and clinical parameters. GCF was collected for 30 seconds on paper strips, and levels of ICTP and IL-1 were determined using radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) techniques, respectively. Clinical measurements included probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP)., Results: Deep sites exhibited significantly (P<0.001) higher ICTP and IL-1 levels compared to shallow sites at all time intervals. ICTP demonstrated a stronger association to clinical parameters than IL-1 including a modest correlation (r = 0.40, P<0.001) between ICTP and attachment loss. Significant improvements in PD, CAL, and BOP were observed at 1, 3, and 6 months in all sites (P<0.01). However, non-surgical mechanical therapy did not significantly reduce ICTP and IL-1 levels over the 6-month period. Further examination of subjects based on smoking status revealed that ICTP levels were significantly reduced at 3 and 6 months and IL-1 levels reduced at 3 months among non-smokers only., Conclusions: A single episode of non-surgical mechanical therapy did not significantly reduce biochemical markers associated with bone resorption in patients exhibiting chronic periodontitis. Future longitudinal studies are warranted to specifically evaluate the relationship between C-telopeptide pyridinoline cross-links and periodontal disease progression.

This case report describes the formation of an unusual unaesthetic gingival enlargement during a five year post operative period subsequent to a subepithelial connective tissue graft placed facial to teeth #4 and #6. Histological assessment of the enlarged tissue indicated that it consisted of viable bone and marrow. The exostosis was reduced with rotary instruments and acceptable soft tissue aesthetics were created using a carbon dioxide laser for gingivoplasty. Possible causes for this unusual enlargement are discussed.

Over the past 30 years, research has validated the success of osseointegrated implants as a viable alternative to fixed or removable prosthetic restorations. Periodontists are extensively trained in surgical procedures to treat and maintain patients with edentulous and partially edentulous arches. They also have a primary role in treatment planning and maintenance therapy. Thus, periodontists routinely integrate endosseous implants into periodontal therapy. This paper was prepared by the Research, Science and Therapy Committee of the American Academy of Periodontology and is intended to inform the dental profession regarding the utility of endosseous dental implants in the treatment of full and partial edentulism.

Background: The purpose of this longitudinal study was to determine the clinical status and the composition of the subgingival microbiota of dental implants and natural teeth in patients with a history of periodontitis., Methods: Twenty-five partially edentulous patients treated for moderate to advanced adult periodontitis and having a total of 42 implants participated in this 3-year study. The assessment of clinical status was done 1, 2, and 3 years after prosthetic loading (T1, T2, and T3, respectively). Clinical parameters evaluated included probing depth (PD), clinical attachment level (CAL), gingival index (GI), and plaque index (PI). The subgingival microbiota at peri-implant and periodontal sites were analyzed at T1 and T2., Results: No significant difference in clinical parameters between implants and teeth and within the 2 groups between different time points was observed through the study. PD and CAL measurements of sampled periodontal and peri-implant sites did not show any statistically significant difference through the study and between the 2 groups. PI of sampled periodontal sites showed a statistically significant improvement during the study. From the morphological observation of the subgingival microbiota, a significant difference in the composition of motile rods between implants and teeth was found at T1. There were no differences detected in the subgingival microbiota, culturally identified at peri-implant and periodontal sites for the duration of the study., Conclusions: In conclusion, implants were colonized by the indigenous periodontal microbiota and were well maintained in patients with a history of periodontitis. No significant association between progressing or non-progressing periodontal or peri-implant sampled sites in terms of loss of attachment and infection with at least one of the searched periodontal pathogens was found, suggesting that the presence of putative periodontopathogens at peri-implant and periodontal sites may not be associated with future attachment loss or implant failure.

Periodontal plastic procedures are performed to prevent or correct anatomical, developmental, traumatic, or plaque induced defects of the gingiva, alveolar mucosa, or bone. The majority of these procedures are performed in combination with restorative and/or orthodontic therapy with the primary goal of enhancing aesthetics. In this review some of the more prominent techniques currently available to address mucogingival deficiencies including pedicle grafts, free soft tissue grafts, and combination grafts are illustrated. In addition, potential complications associated with periodontal plastic procedures are discussed.

Periodontal plastic procedures are performed to prevent or correct anatomical, developmental, traumatic or plaque-induced defects of the gingiva, alveolar mucosa or bone. The majority of these procedures are performed in combination with restorative and/or orthodontic therapy, with the primary goal of enhancing esthetics. In this review, some of the more prominent techniques currently available to address mucogingival deficiencies, including pedicle grafts, free soft tissue grafts and combination grafts, are illustrated. In addition, potential complications associated with periodontal plastic procedures will be discussed.

Uniformity, surface roughness, and chemical phase structure are all important features of implant coatings. While the first two variables are important for implant placement, the phase structure affects implant fixation. This study examined the coating morphology and the amount, size, and distribution of crystalline regions of press-fit and screw-type dental implants. Implants obtained from five commercial vendors were sectioned sagittally, mounted, and polished to reveal the coating microstructure. The crystalline phase content varied depending on the implant supplier; however, general trends were observed. Amorphous regions were predominantly found at the metal interface and decreased toward the outside of the coating, producing a crystallinity graded coating. The distal end of the implant, where heat build-up was more likely during the coating procedure, displayed a higher crystalline content and larger crystalline regions. Similarly, the thread apex consisted of more of a crystalline phase. The results of this study of coating microstructure may be used to improve the quality and performance of implants and may help to explain different in vivo responses to the many available varieties of hydroxyapatite-coated dental implants.

Supragingival plaque control is essential for the maintenance of oral health. Despite the many chemotherapeutic agents available as mouthrinses and toothpastes, mechanical plaque removal is still the best method to achieve effective plaque control. This is due, in part, to the lack of development of oral antimicrobials with the effectiveness and substantivity of chlorhexidine gluconate but without its adverse effects of dental staining and calculus formation. The use of the numerous mechanical (manual and electric) oral hygiene devices extant and their effectiveness, however, are dependent upon patient dexterity and compliance and concomitant active professional treatment for the monitoring of home care, oral hygiene instruction and patient motivation. This paper evaluates the current methods available to reduce plaque and gingivitis with emphasis on their effectiveness at both supragingival plaque control and disease prevention. In addition, recent studies on the newer oscillating/rotating electric plaque removers and interdental cleaning devices will be discussed as related to their efficacy and compliance.

This study examined for 3 years the changes in periodontal status and the possible correlations with selected subgingival microbiota and diabetic conditions in a group of 16 insulin-dependent diabetes mellitus (IDDM, JD) patients as compared with their 16 healthy cohabiting siblings (HS). JD patients were monitored every 3 months for levels of glycosylated hemoglobin (HbA1C). Clinical and microbiological parameters were measured 6 weeks before drawing blood to determine levels of HbA1C. Periodontal parameters were measured at baseline (TO), year 2 (T2), year 3 (T3) and included: probing depth (PD), attachment level (AL), sulcus bleeding index (SBI), and plaque index (PI). Two sites in each patient were selected for microbial samples: a mesio-facial aspect of the maxillary right first molar (defined as constant site, CS) and a site with the greatest probing depth (defined as deepest site, DS). Microbial samples were analyzed by culture techniques. No significant differences in clinical parameters were found between diabetics and healthy siblings at any examination. The SBI in the non-diabetic group at T2 and at T3 was significantly lower than at baseline. PD and AL of constant sites in the diabetic group at T3 were significantly higher than baseline. There was a significant increase in Prevotella intermedia at T3 as compared with baseline for deepest sites in the diabetic group. Cluster analysis revealed, in a former study, two clusters (IV and V) at baseline which were significantly different from the overall mean regarding composition of Porphyromonas gingivalis and Capnocytophaga spp. They were not significantly different for periodontal parameters from TO to T3. These data would suggest no significant differences in clinical parameters between the diabetics and non-diabetic siblings throughout this 3-year longitudinal study.

Retrospective data from sinus floor augmentation bone grafts were collected from 38 surgeons for 1007 sinus grafts that involved the placement of 2997 implants over a 10-year period, with the majority of the implants followed for 3 years or more postrestoration. There were 229 implant failures reported. Various root-form implants and grafting modalities were used. A consensus conference was organized to evaluate the data and reach a consensus on optimal treatment protocols. The complete database demonstrated a 90.0% success rate for implants placed in sinus grafts with at least 3 years of function. Differences in grafting materials, implant surfaces, and timing protocols were statistically analyzed. However, the database was so multivariate and multifactorial that it was difficult to draw definitive conclusions; these must await controlled prospective studies. The consensus conference therefore developed and voted on multiple consensus statements derived by committee review for bone graft materials, type of implants, timing for implant placement, failure analysis, radiographic analysis, indications/contraindications, prosthetics, and nomenclature. Several consensus statements were obtained, the most significant being that the sinus graft should now be considered a highly predictable and effective therapeutic modality.

The stability and degradability of hydroxyapatite coatings on dental implants depends on the dissolution of the individual chemical phases. Hydroxyapatite-coated dental implants exhibit a range of amorphous-phase content. Two tests were conducted to observe the course of coating degradation. The first test showed degradation of both crystalline and amorphous coatings by cracking and dissolution after immersion in Ringer's solution. Concomitant saturation of the implants in the solution modified the coated surface with precipitated crystalline apatite. A second test, intended to replicate the conditions of infection by decreasing pH, illustrated preferred dissolution of the amorphous phase, liberating crystalline segments. It is expected that morphologic changes could influence the rate of bone bonding and therefore could alter or control implant-tissue interactions.

Two patients were referred to the Graduate Periodontal Clinic, one for placement of dental implants, the other for treatment of advanced periodontal disease. It was determined from an analysis of the Hounsfield scales of bone density from a CT scan that the patient requesting dental implants had severe osteoporotic changes and was, therefore, not a good candidate for the procedure. The second patient's medical history revealed multiple fractures occurring over the years that suggested the presence of osteoporosis. This diagnosis was subsequently confirmed by referral of the patient to an osteoporosis clinic.

Over the past decade much has been elucidated concerning the cellular and molecular basis for health and disease. This increase in information has created a large gap in knowledge between the research scientist and the clinician. The following review attempts to bridge this gap by describing each of the thirteen interleukins and relating their functions to the clinical presentation of periodontal disease.

The periodontal status and subgingival microflora of insulin-dependent juvenile diabetic (JD) patients (n = 16, mean age = 11.3) were compared with that of their non-diabetic cohabiting healthy siblings (HS, n = 16, mean age = 13.2). JD patients were monitored every 3 months for levels of glycosylated hemoglobin (HbA1c) and clinical and microbial parameters were measured 6 weeks before drawing blood for levels of HbA1c (M% = 8.76). Clinical indices, measured for the entire permanent dentition, included: probing depth (PD), attachment level (AL), sulcus bleeding index (SBI), and plaque index (PI). Subgingival plaque samples were obtained at 2 sites from each subject; whenever possible, the site with the deepest probing depth and the mesial aspect of the maxillary right first molar were used. Microbial analyses were determined by cultural characteristics and biochemical tests. No significant differences were detected in any of the clinical indices for the entire dentition. The mean AL for JD sites was 2.32 +/- 0.83 mm and for HS sites was 2.2 +/- 0.85 mm. Mean percentage of total cultivable anaerobic microflora included Capnocytophaga spp. (JD, 13.21%; HS, 11%) and Porphyromonas gingivalis (JD, 5.1%; HS, 7.9%). Differences between the two groups were not statistically significant. When cluster analysis was performed on sampled sites, one cluster group in JD patients showed significantly elevated P. gingivalis and lower Capnocytophaga spp. levels as compared to the overall mean. The clinical parameters of this cluster were characterized by statistically significant greater loss of attachment and probing depth. These data would suggest few differences between JD patients and their HS in this population.

The principle of guided tissue regeneration using barrier membranes has become an accepted method for the treatment of teeth with severe osseous defects and furcation involvement. A technique was developed using an expanded polytetrafluoroethylene soft-tissue patch, 1 mm thick (W.L. Core and Assoc., Flagstaff, AZ), in conjunction with an alloplast hydroxyapatite bone substitute (HA-500, 40-60 mesh) (Orthomatrix, Minneapolis, MN), for space maintenance in severe osseous defects. A case report is presented which demonstrates the successful use of this method, and includes a fourth-year re-entry procedure that illustrates the complete bone fill and obturation of a severe vertical defect and Class II furcation of a mandibular first molar.

The aim of this study was to examine the subgingival microflora associated with failing implants, and to determine their susceptibility to commonly used antibiotics in periodontal therapy and dental practice. Thirteen partially edentulous patients with 19 failing implants were selected. Clinical examination included probing depth, attachment level, gingival index, plaque index, and radiographic analyses. Two subgingival plaque samples were taken from each failing implant and analyzed for microbial composition. Fusobacterium nucleatum, Porphyromonas gingivalis, and Prevotella intermedia were the prevalent cultivable microflora. Antimicrobial susceptibility of isolates was determined by the agar dilution technique. Antibacterial activity of penicillin G, amoxicillin, amoxicillin-clavulanate, and the combination amoxicillin-metronidazole was significantly higher than with other antibiotics tested. These data indicated that the commonly-used antibiotics were highly effective against bacteria isolated around failing implants, which would suggest the use of these antibiotics to control peri-implant infections.