Comparison of relative TLR-2 and TLR-4 expression level of disease and healthy gingival tissue of smoking and non-smoking patients and periodontally healthy control patients.

BACKGROUND: Toll-like receptors are a family of sensor proteins that induce the inflammatory diseases in context of microbial infection. The role of these proteins in periodontal disease and their interaction with smoking status are yet to be investigated. The aim of the present study was to evaluate the effect of smoking on gene expression of toll like receptor 2 (TLR-2) and toll-like receptor 4 (TLR-4) in patients with periodontitis. METHODS: RNAs were extracted from gingival biopsies of healthy sites (no bleeding on probing and pocket depth ≤3 mm) as well as diseased sites (with bleeding on probing and pocket depth ≥5 mm) of 20 smoker and 17 non-smoker subjects with chronic periodontitis. Gingival biopsies from eight periodontally healthy, never-smoker subjects served as control. Real-time PCR was carried out to evaluate the relative quantities of TLR-2 and TLR-4 mRNA concentrations. RESULTS: Regardless of smoking status, the relative expression levels of TLR-2 and TLR-4 were significantly greater (about 3 fold) at diseased sites compared to healthy sites of patients with periodontitis and healthy controls (p < 0.05). In sites with periodontitis, smoking caused an increase of about 6.5 fold in mRNA levels of TLR-4 in gingival tissue (p < 0.05). CONCLUSIONS: Although periodontitis might significantly increase TLR-2 and TLR-4 gene expression in gingival tissues, smoking habit in periodontitis subjects could selectively potentiate TLR-4 gene expression.

Left-to-right distribution of periodontal disease.

AIM: Symmetry is a property established in many human biological systems and it is reasonable to expect that it may also exist in the mouth. The objective of this study was to examine whether there is a similar left-to-right distribution in periodontal disease. METHOD: Records of 197 patients from the Periodontics department of The Royal Dental Hospital of Melbourne were analysed. The clinical parameters recorded were pocket probing depth, recession, bleeding on probing, mobility and furcation involvement. RESULTS: The average age of our sample group was 47.5 years old, with 34.5% men and 65.5% women. The results demonstrated significant left-to-right distribution with all the periodontal indices recorded. CONCLUSION: The findings support previous studies that show that a similar left-to-right distribution exists in the population studied.

Pattern of cigarette smoking effect on periodontal pocketing and attachment loss: a retrospective study.

AIM: The aim of the present retrospective study was to evaluate the local effects of smoking on periodontium and to assess the patterns of periodontitis (pocket depths and attachment loss) in smokers and non-smokers. METHODS: In this study, records of 126 non-smokers and 51 smokers (≥ 5 cigarettes/day) periodontitis patients were evaluated and probing pocket depth (PPD), clinical attachment level (CAL) and bleeding on probing (BOP) data were collected from clinical patients records. Patients' data were subject to two sample t-tests to assess the difference between the groups and to analysis of variance using the generalized linear model to seek associations between smoking and site positions, age and clinical parameters. RESULTS: The difference between CAL of smokers and non-smokers was greatest at the anterior maxillary palatal sites (P = 0.002) and reached 1 mm. When the effect of different site positions as well as smoking as a between subject variable and age as a co-variate on the attachment level measurements were assessed using analysis of variance, significant effects for smoking, jaw (lower versus upper) and anterior-posterior position as well as age were detected. No significant interactions were found between smoking and any of the three position variables. CONCLUSION: Lack of interaction between smoking and any of the three position variables indicates that the destructive effects of smoking on the periodontal tissues maybe mainly from systemic side-effects and almost independent of the site position within the mouth, although some additional local effects may be present in areas such as anterior palatal sites.

An evaluation of bovine derived xenograft with and without a bioabsorbable collagen membrane in the treatment of mandibular Class II furcation defects.

BACKGROUND: The aim of this study was to compare the clinical outcomes of applying Bio-Oss, an anorganic bovine bone xenograft (control group) to the combined use of Bio-Oss and Bio-Gide (a bioabsorbable collagen membrane) (test group) in human mandibular Class II furcation defects. METHODS: A total of 18 furcations (8 tests and 10 controls) in 14 patients suffering from chronic periodontitis were treated in this randomized clinical trial. Open vertical and horizontal furcation depths (OVFD and OHFD), vertical and horizontal clinical attachment levels (VCAL, HCAL), probing depth (PD) and free gingival marginal level (GML) were among the clinical parameters measured prior and six months after treatment, at re-entry surgery. The data were analysed by statistical tests while a p value less than 0.05 was considered significant. RESULTS: At the surgical re-entry, the mean reduction for OVFD of the control and test groups was 1.9 +/- 1.3 and 2.1 +/- 1.0, and for OHFD 2.1 +/- 0.7 and 2.4 +/- 1.3, respectively. The control and test treatments resulted in significant reductions in PD, VCAL and HCAL measurements at re-entry but there was no statistically significant difference between the two treatments in all soft and hard tissues measurements. CONCLUSIONS: This clinical trial failed to demonstrate the superiority of the combined use of Bio-Gide and Bio-Oss to the use of Bio-Oss alone, although both therapies resulted in significant gains in attachment level and bone fill.

Effect of subgingival scaling during supportive therapy.

BACKGROUND, AIMS: This prospective study was designed to investigate the rôle of root débridement at 3 month intervals for patients with periodontitis whose disease had persisted following the completion of conventional periodontal treatment. METHODS: 39 maintenance patients with at least 4 pockets at least 4 mm deep were assigned to coronal scaling (CS) and subgingival scaling (SS) groups. Probing depths (PD), bleeding on probing (BOP) and relative attachment levels (RAL) were recorded at all eligible sites at baseline and 3, 6, 9 and 12 months later. Plaque index scores were recorded at the 12-month visit. At every visit, following data collection, both groups received a coronal scaling and the SS group, in addition, received a thorough subgingival débridement. In the CS group, subgingival débridement was performed only for 'loser' sites which inhibited loss of attachment > or = 2 mm relative to baseline values. Due to low compliance, only 31 patients completed the study. Thus, data analyses were carried out for 130 sites in 17 CS group patients and 146 sites in 14 SS group patients. RESULTS: During the course of the study, 21 loser sites were identified in each group, but the difference in proportion of loser sites between groups was not significant. Furthermore, although there was a trend toward PD reduction in both groups throughout the study, mean PD, RAL and BOP values were not significantly different from baseline values at any time point, and there were no significant differences between groups with respect to these variables. Mean plaque scores measured at the 12-month visit revealed no significant differences between groups. CONCLUSION: These findings call into question the value of performing repeated subgingival scaling at 3-month intervals for patients with persistent disease.

Cell division, synthetic capacity and apoptosis in periodontal lesions analysed by in situ hybridisation and immunohistochemistry.

In this study, we investigated the synthetic and proliferative activity of infiltrating mononuclear cells in sections of granulation tissue from periodontitis lesions in both adult periodontitis (AP) and early onset periodontitis (EOP) patients. We also investigated the role of apoptosis in the remodelling of the inflamed tissue. We utilised a Ki-67 antigen specific antibody and a histone messenger RNA (mRNA) probe to detect cells undergoing cell division in the sections. Oligonucleotide probes for 28S ribosomal RNA and for the detection of poly A mRNA were utilised to detect cells with synthetic capacity. Apoptosis was determined using terminal transferase labelling of fragmented DNA with Biotin labelled dUTP. Biopsies of granulation tissue were obtained from 9 AP patients, from 10 EOP patients and for comparative purposes, biopsies of gingival tissue from 4 patients with AP. There were no differences regarding the relative proportions of cells with synthetic capacity or in the numbers of dividing cells in the periodontitis tissue sections. However, we observed an increase in the number of dividing cells in the AP granulation tissues compared to the AP gingival sections and that these cells were predominantly fibroblast like in appearance. Apoptotic cells consisted mainly of connective tissue cells; mainly fibroblasts with few if any leukocytes being apoptotic other than polymorphonuclear leukocytes. Only a few cyto-phagocytic macrophages were ever observed in the gingival and granulation tissues. We conclude that the turnover of infiltrating leukocytes in inflamed periodontal tissue is low, that they probably arrive at this site by recruitment from distant lymph nodes, and that neither cell division nor programmed cell death significantly alter the numbers of inflammatory cells. On the other hand, fibroblast apoptosis and cell division occur within the periodontium as these are typical processes in the normal turnover and remodelling of these tissues.

Relative proportions of mononuclear cell types in periodontal lesions analyzed by immunohistochemistry.

In this study, we investigated the relative proportions of infiltrating mononuclear inflammatory cells in sections of granulation tissue from periodontitis lesions in both adult periodontitis (AP) and early onset periodontitis (EOP) patients. We utilised a set of cluster of differentiation (CD) antigen-specific monoclonal antibodies to detect different cell types within the tissues. These included anti-CD 20 (B cells), anti-CD 3 (pan T cells) and anti-CD 45RO (memory T cells), anti-CD 4 (helper T cells) anti-CD 8 (suppressor T cells) and anti-CD 68 (monocyte/macrophage). Biopsies of granulation tissue were obtained from 9 patients with adult periodontitis (AP), from 10 patients with early onset periodontitis (EOP) and for comparative purposes, biopsies of gingival tissue from 4 patients with AP. A significantly greater number of T cells (p < 0.05) were observed in EOP and gingival sections than in AP sections. In addition, a greater number of B cells were observed in the granulation tissues than in the gingiva (p < 0.05). The relative numbers of B cells (CD 20). T cells (CD 3) and macrophages (CD 68) were expressed as a percentage of their combined total for each of the patient groups and indicated that the proportion of B lymphocytes was greater in AP sections than in EOP or gingival sections (p < 0.02). The proportion of T cells was lower in the AP periodontitis sections than in the EOP periodontitis sections (p < 0.05). There were no significant differences in the proportion of macrophages between the 3 categories of tissue specimens. The relative ratios of B cells (CD 20) to T cells (CD 3) and B cells (CD 20) to memory T cells (CD 45RO) and macrophages (CD 68) to T cells (CD 3) and memory T cells (CD 45RO) were analyzed and indicated that there was a significant increase in the B to T cell ratio in AP sections compared to EOP and gingival sections (p < 0.02). There was also a significant increase in the macrophage to T cell ratio in AP sections as indicated by CD 68 to CD 3 ratios (p < 0.05). There were no differences regarding the relative proportions of memory T cells or in the ratios of CD 4+ to CD 8+ T cells in the different disease categories. In conclusion, these differences in the relative proportions of B cells, T cells and macrophages may reflect a difference in the immunopathology of AP and EOP.

A six-month comparison of three periodontal local antimicrobial therapies in persistent periodontal pockets.

BACKGROUND: Currently, several local antimicrobial delivery systems are available to periodontists. The aim of this 6-month follow-up parallel study was to evaluate the efficacy of three commercially available local delivery systems as adjuncts to scaling and root planing in the treatment of sites with persistent periodontal lesions. METHODS: Seventy-nine patients with 4 pockets > or = 5 mm and bleeding on probing and/or suppuration were randomized into 4 treatment groups which included: scaling and root planing alone (S) (20 patients), or in conjunction with the application of 25% tetracycline fibers (S+Tet) (19 patients), or 2% minocycline gel (S+Min) (21 patients), or 25% metronidazole gel (S+Met) (19 patients). Clinical measurements were taken at baseline, 6 weeks, 3 months, and 6 months after antimicrobial application. Treatments were applied using the distributors' recommended protocols. RESULTS: All 4 therapies resulted in significant improvements from baseline in probing depth, attachment level, bleeding on probing, and the Modified Gingival Index (MGI) scores. The improvements in clinical parameters were greater in all 3 adjunctive treatment groups than scaling and root planing alone. The mean probing depth reductions at 6 months were: scaling + tetracycline = 1.38 mm; scaling + metronidazole = 0.93 mm; scaling + minocycline = 1.10 mm; and scaling alone = 0.71 mm. The probing depth reduction at all time points was significantly greater in the scaling plus tetracycline fiber group than the scaling and root planing alone group (P<0.01). There was also a significant improvement for scaling plus tetracycline fiber application over scaling and metronidazole at both 6 weeks and 3 months, although this did not remain significant at the 6-month visit. While the frequency of sites with suppuration was markedly reduced following all antimicrobial treatments, the most effective reductions were seen in the scaling plus tetracycline fiber group, followed by the minocycline group. CONCLUSIONS: Although all 3 locally applied antimicrobial systems seem to offer some benefit over scaling and root planing alone, a treatment regimen of scaling and root planing plus tetracycline fiber placement gave the greatest reduction in probing depth over the 6 months after treatment.

The effect of smoking on mechanical and antimicrobial periodontal therapy.

The aim of this investigation was to evaluate the effect of smoking on the outcome of periodontal therapy. The study consisted of 54 patients who participated in a 4-group parallel-arm clinical trial on the efficacy of three locally delivered antimicrobial systems as adjuncts to scaling and root planing in the treatment of sites with persistent pocketing after a course of scaling and root planing. These groups included scaling and root planing either alone (S) (n = 3), or in conjunction with the application of 25% tetracycline fibers (S&T) (n = 13), 2% minocycline gel (S&Mi) (n = 14), or 25% metronidazole gel (S&Me) (n = 14). In each patient four pockets > 5 mm with bleeding on probing (BOP) and/or suppuration were studied. The number of subjects who smoked was: 8 (61.5%) in the S&T group, 8 (57.1%) in the S&Mi group, 6 (42.9%) in the S&Me group, and 6 (46.2%) in the S group. The probing depth, attachment level and other clinical parameters were assessed at baseline and 6 weeks after treatments. The clinical results of this comparative study have been previously reported. Regardless of the type of treatment, the change in the probing depth (delta PD) and attachment gain (delta AL) were greater in non-smoker subjects than smoker subjects. delta PD was 1.14 mm versus 0.76 mm (P = 0.019), and delta AL was 0.52 mm versus 0.50 mm at (P = 0.845) for non-smokers and smokers respectively. The analysis of variance using the general linear model (GLM) was used for delta PD and delta AL and took into account the variations in the treatments, number of smoker subjects per group, and baseline probing depth. There was a significant interaction between the "smoking" and the "baseline PD." Further analysis using linear regression indicated that, while there was a significant relationship between the baseline PD and the delta PD or delta AL among the non-smokers, weak and insignificant relationship existed among the smoker subjects. Thus, smoking may have an important role in determining the prognosis of periodontal treatment, particularly in persistent and deep pockets.

Comparison of 3 periodontal local antibiotic therapies in persistent periodontal pockets.

The aim of this study was to evaluate the efficacy of 3 commercially available periodontal systems for local delivery of antibiotics as adjuncts to scaling and root planing in treatment of sites with persistent periodontal lesions following a course of scaling and root planing. Fifty-four patients with 4 pockets > or = 5 mm and bleeding on probing and/or suppuration were randomized in 4 treatment groups including: scaling and root planing plus application of 25% tetracycline fiber (S + Tet) (13 patients), scaling and root planing plus application of 2% minocycline gel (S + Min) (14 patients), scaling and root planing plus application of 25% metronidazole gel (S + Met) (14 patients), and scaling and root planing alone (S) (13 patients). Clinical measurements were taken at baseline and 6 weeks after the end of treatment periods. All treatments were applied using the distributors' recommended protocols and resulted in significant improvement in probing depth, attachment level, bleeding on probing and the modified gingival index (MGI) scores. The improvements in clinical parameters were greater in all three adjunctive treatment groups than scaling and root planing alone. The mean probing depth reductions were: S + Tet = 1.35 mm, S + Met = 0.95 mm, S + Min = 0.87 mm and S = 0.60 mm. The probing depth reduction was significantly greater in the scaling plus tetracycline fiber group than the scaling and root planing alone group (P = 0.002). The difference between groups in improvement of attachment level or bleeding on probing was not significant Scaling plus tetracycline fiber treatment resulted in the greatest reduction in the MGI scores which was significantly greater than all other groups. While the frequency of sites with suppuration was markedly reduced following all treatments, it reached zero in the scaling plus tetracycline fiber group. No serious adverse effects were observed or reported for any treatment. While all three locally applied antimicrobial systems seem to offer some benefit over scaling and root planing alone, a treatment regimen of scaling and root planing plus tetracycline fiber replacement gave the greatest advantage in the treatment of persistent periodontal lesions at least during the 6-week period following treatment.

The effect of subgingival antimicrobial therapy on the levels of stromelysin and tissue inhibitor of metalloproteinases in gingival crevicular fluid.

Recent investigations imply that a key mechanism in the pathogenesis of periodontal disease may be the ability of oral microorganisms to induce production and/or activation of matrix metalloproteinases (MMPs) in the host tissues. It has been suggested that the pharmacologic inhibition of MMP activity could play an important role in achieving a desirable outcome in periodontal therapy. The efficacy of locally delivered antibiotics on the level of gingival crevicular fluid (GCF) stromelysin (SL) and tissue inhibitor of metalloproteinases (TIMP) on sites with a history of a poor response to mechanical treatment was studied. Fifty-two patients with 4 periodontal pockets > or = 5 mm and bleeding on probing were randomized into four groups of 13 patients. One group received scaling and root planing alone and the other three groups received scaling and root planing plus a locally delivered antimicrobial system. These included 25% tetracycline fiber, 2% minocycline gel, and 25% metronidazole gel. The GCF samples taken at baseline and 6 weeks after treatments were analyzed using an enzyme linked immunosorbent assay (ELISA). GCF SL levels significantly decreased after adjunctive tetracycline fiber (paired t-test, P = 0.020) and minocycline gel (paired t-test, P = 0.023) treatments whereas it remained almost unchanged in the other two groups. While the GCF TIMP level did not change significantly in the scaling and root planing alone group, it significantly increased for all three adjunctive antimicrobial treatments (for tetracycline fiber P < 0.001, minocycline gel P = 0.005, metronidazole gel P < 0.001). The use of adjunctive locally delivered antimicrobial systems, particularly the tetracycline family, may offer an advantage in changing the metalloproteinase profile of the GCF to one more compatible with periodontal health.

An evaluation of the Nd:YAG laser in periodontal pocket therapy.

The aim of this study was to determine whether the Nd:YAG laser energies of 50 and 80 mJ at 10 pulses per second (pps) were capable of improving the clinical parameters associated with periodontal disease. These energy settings were chosen as previous work indicated that higher values would damage root surfaces and that 80 mJ had an in-vitro bactericidal effect. Eighty periodontally affected sites in teeth scheduled for extraction from 11 patients with adult periodontitis were randomly placed in one of the following four treatment groups: 1. laser treatment at 50 mJ, 10 pps for 3 minutes; 2. laser treatment at 80 mJ, 10 pps for 3 minutes; 3. scaling and 4. untreated control. Probing depth, bleeding on probing (BOP), plaque index, gingival index and gingival crevicular fluid (GCF) volume were measured at baseline and week 6. Baseline subgingival microbiological samples were collected, then repeated immediately after treatment and at week 6 to assess the total anaerobic colony forming units (CFU). Only the scaling group showed a significant reduction in pocket depth and BOP (P < 0.001). The microbial samples taken immediately after scaling and laser at 80 mJ and 10 pps treatments showed a significant reduction in total CFU compared with the baseline (P < 0.01), which was sustained only in the scaling group until week 6. Electron microscopy did not reveal any heat damage on the root surfaces. This study demonstrated that application of Nd:YAG laser pulses of 50 mJ and 80 mJ failed to improve the clinical and microbiological parameters of periodontal disease.

An evaluation of the effects of an Nd:YAG laser on subgingival calculus, dentine and cementum. An in vitro study.

The aim of this study was to evaluate the effects of Nd:YAG laser treatment on subgingival calculus, cementum and dentine, in vitro at different power settings and durations. The study included 2 experiments. In the 1st experiment, 32 extracted teeth with calculus were divided into 8 laser treatment groups. Each tooth was treated on 2, 3 or 4 sites. In the 2nd experiment, 3 extracted cementum covered teeth and 3 extracted root planed teeth with exposed dentine were selected. 1 surface of each tooth was subjected to 8 different laser treatments. In both experiments, all specimens were assessed using scanning electron microscopy. Micrographs were taken from each treated site at x 100 and x 750 magnifications. An arbitrary scale (from 0 to 3) was used to score the degree of damage caused by the laser. Generally, the laser caused greater damage on calculus than either cementum or dentine. Linear regression analysis showed that higher total energy input caused a greater mean damage score on calculus (R2 = 66%, p < 0.001). 3-way analysis of variance showed that for calculus, the power setting, number of pulses per second and the duration of exposure contributed independently to the mean damage score in an additive way. Cementum specimens were not affected by treatment 1 (50 mJ, 10 pps, 1 s), treatment 2 (50 mJ, 10 pps, 5 s), and treatment 5 (50 mJ, 20 pps, 1 s). Dentine specimens were not affected by treatment 1 (50 mJ, 10 pps, 1 s).(ABSTRACT TRUNCATED AT 250 WORDS)