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Notes: Abstract. The aims of the present study were to assess radiographically the effects of scaling/root planing combined with antibiotic therapy using tetracycline fibers (TCF): (II) on alveolar bone density and linear discriptors and (II) on supracrestal soft tissue density, 19 subjects with generalized adult periodontitis (with at least 20 teeth present, at least 4 teeth with pockets 〉4 mm and bleeding upon controlled force probing) and high cultural counts of Porphyromonas gingivalis were recruited from a pool of 57 patients. The full mouth treatment group (FT) consisted of 10 patients, who underwent a full mouth supra-gingival scaling and prophylaxis treatment and were instructed to rinse 2× daily with a 0.1% chlorhexidine solution. 1 week later, tetracycline-hydrochloride-containing fibers (Actisite® periodontal fiber) were applied around all teeth. After 7–12 days, the fibers were removed and all teeth were scaled and root planed under local anaesthesia. The chlorhexidine rinsing continued for another 2 months. In 9 subjects (local treatment group LT), 2 teeth with periodontal lesions with pocket probing pepth (PPD) ≥5 mm were treated by placement of tetracycline fibers, which remained in place for 7 to 12 days. Upon removal of the fibers, scaling and root planing was performed on these 2 teeth, while the rest of the dentition renamed untreated, and no chlorhexidine rinse was applied, 2 of the untreated teeth revealing similar periodontal lesions were chosen to represent sites affected by untreated periodontitis (NT). In this group, a limited local treatment was performed (2 teeth) with the inherent potential for recolonization from the untreated pocket sites. Standardized periapical radiographs were obtained from the 4 monitored sites within each patient at baseline (before treatment) and 2 and 6 months thereafter. One radiograph was exposed in a standard way for bone assessment. The second radiograph was underexposed, at about a 1/5 of the original exposure time to allow the evaluation of soft tissue. Mean changes in the near parameters and changes in density (CADIA) observed at multiple sites within each patient and treatment group were used as the best estimate of treatment outcome. Over the observation period of 6 months, a significant difference in bone height changes was found between the untreated sites (median loss –0.29 mm) and the sites from full-mouth treated patients (median gain 0.24 mm p=0.008). When comparing the baseline to the 6 months radiographs, a loss in bone density was observed for the untreated group (median=–2.13 CADIA), Both treatment groups revealed a gain in density (median= 1.58 and 2.43 CADIA for the locally and the full–mouth treated groups, respectively). Differences in density were significant, both between the nontreated and locally treated sites (p= 0.026) and between the nontreated sites and the sites from the full mouth treated patients (p=0.002). The analysis of the soft tissues showed a similar pattern of changes in density to those seen in the bone defect. At 2 months, there was a tendency for loss in density for the nontreated group (median=–0.17 CADIA) that continued over the 6 month period (median =–0.31 CADIA), A significant increase in density was observed for the full–mouth treated sites (median = 1.57 and 0.64 CADIA for the 2 and 6 months radiographs, respectively), A significant increase was also observed for the locally treated group when compared to the untreated sites (median=0.13 and 0.10 CADIA for the 2 and 6 months radiographs, respectively). Comparing untreated sites with full–mouth treated sites, a significant difference was observed for CADIA measurements (p〈0.001). No significant difference was observed comparing locally treated and untreated sites (p=0.24). It was concluded that scaling and root planing combined with TCF therapy can result in increased bone density and alveolar bone height. Full-mouth treatment seemed to result in more pronounced gains compared to local treatment. Untreated sites continued to lose alveolar bone height and density, CADIA of supracrestal soft tissue ROI paralleled the remodelling observed in bone ROI, This is the first controlled study revealing that CADIA of soft tissue ROI in series of underexposed standardized radiographs may render additional valuable information on remodelling of periodontal tissues after therapy.

Notes: Abstract. The aim of this randomized single-blind multicenter controlled clinical trial was to clinically evaluate the effectiveness of adjunctive local controlled drug delivery in the control of bleeding on probing in mandibular class II furcations during maintenance care. 127 patients presenting with a class II mandibular furcation with bleeding on probing were included in the study. They had been previously treated for periodontitis and were participating in supportive care programs in periodontal speciality practices. Treatments consisted of scaling and root planing with oral hygiene instructions (control) and scaling and root planing and oral hygiene combined with local controlled drug delivery with tetracycline fibers (test). The following outcomes were evaluated at baseline and 3 and 6 months after therapy at the furcation site: bleeding on controlled force probing (BOP), probing pocket depth (PD) and clinical attachment levels (CAL). Levels of oral hygiene and smoking status were also assessed. Both test and controls resulted in significant improvements of BOP and PD at 3 and 6 months. The test treatment, however, resulted in significantly better improvements: BOP decreased by 52% in the control group and by 70% in the test group at 3 months; at 6 months, however, the difference was no longer significant. The test treatment resulted in a 0.5 mm greater reduction of PD than the control at 3 months, the improvement was highly significant but its duration did not extend until the 6 months evaluation. No differences were observed in terms of changes in CAL. These data indicate that addition of tetracycline fibers to mechanical therapy alone resulted in improved control of periodontal parameters during periodontal maintenance of class II mandibular furcations. Short duration of the effect, however, requires further investigations to optimize conservative treatment of these challenging defects.

Notes: The presence and distribution of intraepithelial antigen-presenting cells was studied in the keratinized mucosa around healthy osseointegrated implants and teeth. Vimentin, cytokeratins, HLA-Dr, CD18, ICAM-I and CDla-positive cells were assessed by a 3-stage ABC immunoperoxidase system in serial sections from clinically characterized sites. A total of 11 biopsies (7 adjacent to osseointegrated dental implants and 4 adjacent to teeth in healthy volunteers) were qualitatively and quantitatively analyzed. All biopsies displayed the presence of a small inflammatory infiltrate subjacent to themost coronal portion of the junctional epithelium. Intraepithelial antigen-presenting cell markers were present both around implants and teeth. The observations were consistent with the presence of functional local major histocompatibility complex Class II restricted antigen presentation. Quantitative differences were observed by analysis of variance in terms of different locations within the same section (i.e. junctional epithelium vs oral epithelium) and in terms of the source of the biopsy (i.e. implants vs teeth). The significance, if any, of the observed quantitative difference is discussed in terms of different maturity of the local immune response and possible environmental differences. It is concluded that clinically healthy keratinized mucosa around osseointegrated dental implants shares functional similarities with normal gingiva in terms ofantigen presentation. These results further contribute to the characterization of a functional local immune response that represents the basis for long-term clinical success of osseointegrated dental implants.

Notes: A new local delivery device (LDD) capable of releasing silver in periodontal pockets has been developed and tested pre-clinically. Silver has potent antimicrobial effects on Gram-negative periodontal pathogens with a mean in vitro minimum bactericidal concentration (MBC) ≤0.5 μg/ml. This phase 1 study assessed the safety, pharmacokinetics and bioavailability of silver ions delivered intracrevicularly with a resorbable LDD (PocketGuardTM) in a group of 9 volunteers affected with periodontitis. In each subject, a PLGA/PEG LDD loaded with 12% silver nitrate (w/w) was inserted in each of 4 selected pockets ≥5 mm. Serum, gingival fluid and subgingival plaque samples were evaluated before and at various time points after LDD placement for 21 days. At each time point, the concentration of silver in gingival crevicular fluid (GCF) was quantified with an Inductively Coupled Plasma-Mass Spectrometer. Subgingival plaque samples were processed for evaluation of total anaerobic and aerobic counts (CFU/ml). The maximum mean silver concentration in GCF was 1493±709 μg/ml (range 589–2245). It decayed exponentially with a half-life of 7.1±6.1 days (2.7–20.4). Average silver concentrations in excess of 10 μg/ml were detected in each patient for 14 days after LDD placement with the average concentration for all patients in excess of 25 μg/mL at day 21. Total anaerobic counts decreased an average of 1.7±1.9×106 CFU/ml (p=0.0078) from baseline to day 7, indicating that the silver was biologically active. A mild increase in cervical root discoloration was observed at day 21: 0.25±0.31 stain index units. Discoloration that did not resolve spontaneously could be removed at the end of the study with polishing. No systemic effects were observed. It is concluded that local silver concentrations above the MBC in serum were maintained for at least 21 days. A specific microbiologic effect was also observed.

Notes: Expression of vascular cell adhesion molecules (HEV-CAMs) by capillary loops represents an early step necessary for leukocyte extravasation and subsequent migration to sites of inflammation. The purpose of this investigation was to compare, the presence and distribution of ICAM-1, ELAM-1, VCAM-1 and PECAM-1 expression in the microvasculature of healthy gingiva and periimplant keratinized mucosa. The selected HEV-CAMs were detected by a three stage immunoperoxidase technique in serial sections from clinically characterized sites. Biopsies were qualitatively and quantitatively analyzed. All biopsies displayed a small inflammatory infiltrate subjacent to the most coronal extension of the junctional epithelium. HEV-CAMs were expressed both in the sulcular and oral aspects of biopsies. Intensity of ICAM-1, ELAM-1 and VCAM-1 staining, however, was consistently higher in the region of the infiltrated connective tissue subjacent to the most coronal extension of the junctional epithelium. Only a fraction of microvascular loops were positive for ICAM-1, ELAM-1 or VCAM-1 when compared to the constitutively expressed PECAM-1. No significant differences were observed between gingiva and keratinized peri-implant mucosa. It was concluded that in healthy gingiva or peri-implant mucosa 1. HEV-CAM expressing capillary loops were in close topographic association with the inflammatory infiltrate; 2. only a fraction of capillary loops are activated to express ICAM-1 ELAM-1 and VCAM-1 at any given time; and 3. HEV-CAM expression in the periodontium may be influenced by local factors.

Notes: Background:  Chronic periodontitis causes a low-grade systemic inflammatory response; its standard treatment, however, induces an acute inflammatory response. The aim of this study was to describe the systemic inflammatory reactions to an intensive periodontal treatment regimen.Methods:  Fourteen otherwise healthy subjects suffering from severe chronic periodontitis were enrolled in a 1 month pilot single-blind trial. Intensive periodontal treatment, consisting of full-mouth subgingival root debridement delivered within a 6-h period, was performed. Periodontal parameters were recorded before and 1 month after completion of treatment. Blood samples were taken at baseline and 1, 3, 5, 7 and 30 days after treatment. Interleukin-1 receptor antagonist (IL-1Ra), Interleukin-6 (IL-6) and C-reactive protein (CRP) serum concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Complete blood counts were also performed.Results:  One day after treatment, mild neutrophilia and monocytosis (p 〈 0.05) and lymphopenia (p 〈 0.01) were accompanied by a sharp increase in inflammatory markers (IL-1Ra, IL-6, p 〈 0.01). A 10-fold increase in CRP (p 〈 0.001) was detected on day 1 and its kinetics followed a pattern of a classical acute phase response (significantly raised concentrations up to 1 week, p 〈 0.01). At 3–7 days after treatment, subjects presented also with a mild tendency towards a normocytic anaemic state (p 〈 0.01) and a degree of lympho-thrombocytosis (p 〈 0.05). The observed changes were similar to those expected following the well-characterized endotoxin-challenge model of inflammation.Conclusions:  Intensive periodontal treatment produced an acute systemic inflammatory response of 1 week duration and might represent an alternative to classic endotoxin-challenge or drug-induced models to study acute inflammation in humans.

Notes: PMN migration into the gingival sulcus is a tightly regulated process aimed at selectively increasing leukocyte availability at the site of bacterial plaque aggression, i.e. the superficial portion of the junctional epithelium. The evidence reviewed in this paper indicates that, besides the action of complement fragments, arachidonic acid metabolites, formyl peptides and other bacterial products, the establishment of a gradient of ICAM-1 expression across the junctional epithelium and the expression of IL-8 in its superficial layers probably represent important regulatory mechanisms leading to PMN migration into the gingival sulcus. Such mechanisms can be regulated by the autocrine and paracrine action of some pro-inflammatory cytokines and could possibly be initiated by specific bacteria-keratinocyte interactions. The advantage of such a redundant regulatory mechanism leading to PMN transepithelial migration is probably related to the key role of the neutrophil in the maintenance of a local host-parasite equilibrium on one side, and on the tissue injury associated with PMN persistence or random migration within periodontal tissues on the other. Several investigations are in progress aimed at identifying the initial environmental stimuli leading to PMN recruitment into the gingival sulcus and at further exploring the important regulatory events.