Nitric oxide synthesis and severity of human periodontal disease

The expression of the inducible nitric oxide synthase enzyme (iNOS) is a response to an inflammatory stimulus and produces a large amount of nitric oxide (NO), which may act as a cytotoxic molecule against the invading microorganism and may be related to both harmful and beneficial effects to tissues.

OBJECTIVE AND MATERIAL AND METHODS

In order to further characterize the presence of NO in human periodontal disease, we undertook a quantitative study of iNOS positive cells in samples of clinically healthy gingival tissues, plaque-induced gingivitis and localized chronic periodontitis using immunohistochemistry.

RESULTS

A significant increase in the number of iNOS+ cells mm-2 was found in the samples of the gingivitis and periodontitis compared with those of the control. In all groups most of the polymorphonuclear cells showed intense immunoreactivity for iNOS independent of the disease stage, and the percentage of iNOS+ polymorphonuclear cells increased significantly in periodontal disease when compared with the control.

CONCLUSION

Our results indicate that iNOS increases in the presence of periodontal disease. In addition, our findings suggest that polymorphonuclear cells present an additional activation pathway in periodontal disease, expressing significant iNOS and probably representing an important source of NO in human periodontal disease that has not been previously reported.

[Comparison of surgical and nonsurgical techniques in periodontology]

Actually, there's an evolution of the periodontal treatment. Non surgical therapy is the main way of treatment today. Surgery takes place generally after non surgical therapy and reevaluation. The aim of this work is to compare these two treatments in relation with clinical parameters, to indicate the best therapy for the patient.

Treatment of furcation defects with an allograft-alloplast-tetracycline composite bone graft combined with GTR: human histologic evaluation of a case report

The purpose of this study was to histologically evaluate furcation defects in humans treated with an allograft-alloplast-tetracycline composite graft combined with an absorbable membrane for guided tissue regeneration (GTR). Three teeth with Class II furcation involvement on the buccal aspects were included in this study. A notch was placed in calculus during the procedure to serve as a reference point for histologic evaluation. The defects were then treated with an allograft-alloplast-tetracycline composite graft combined with an absorbable membrane for GTR. At 6 months postoperative, the teeth were extracted with conservative block sections and processed for histologic evaluation. Regeneration (new bone, cementum, and connective tissue attachment) coronal to a notch could be seen in one of the three defects treated. In the other two defects, a new connective tissue attachment was demonstrated (new connective tissue attachment into new cementum) in the notch placed in calculus. In this study, regeneration of a furcation defect in a human was documented with histology.

Aggressive periodontitis: 5-year follow-up of treatment

BACKGROUND

The hypothesis that in subjects with aggressive periodontitis, a long-term stability of periodontal health can be achieved following comprehensive mechanical/surgical and systemic antimicrobial therapy was tested in this prospective study.

METHODS

Thirteen patients (36.9+/-7.4 years) with aggressive periodontitis were monitored before and up to 5 years following periodontal therapy. Clinical attachment levels (CAL) were assessed pretherapy, and at 3 months following completion of active periodontal therapy supplemented by amoxicillin plus metronidazole. All subjects were subsequently enrolled in a maintenance program and provided with supportive periodontal therapy with 3 to 4 appointments annually. Reexaminations were performed after 6 months and 1, 2, 3, 4, and 5 years. The data were analyzed using the method of generalized estimating equations (GEE) for CAL changes from baseline to the 3-month visit, and from completion of periodontal therapy to each annual visit up to the 5-year follow-up reappointment.

RESULTS

During the 5-year study, all subjects strongly benefited from periodontal treatment. Between baseline and the 3-month reexamination, the CAL levels revealed a significant decrease of 2.23 mm (95% confidence interval [CI]: 1.77 to 2.69 mm; P < or =0.001). At the 5-year maintenance visit, the CAL changes ranged from -0.04 to +0.29 mm with no further statistically significant periodontal breakdown (P >0.05). Five years after surgery, 3.2% of the treated sites demonstrated a further CAL gain > or =3 mm. A stabilization (CAL -2 to +2 mm) occurred in 94.6% of the cases. The number of periodontal sites experiencing a breakdown varied from 5.3% at 6 months to 2.2% at 5 years.

CONCLUSIONS

In aggressive periodontitis, comprehensive mechanical/surgical and antimicrobial therapy is an appropriate treatment regimen for long-term stabilization of periodontal health. In this study, periodontal disease progression was successfully arrested in 95% of the initially compromised lesions, while 2% to 5% experienced discrete or recurrent episodes of loss of periodontal support.

Supracrestal soft tissue preservation with enamel matrix proteins in treatment of deep intrabony defects

BACKGROUND/AIMS

The purpose of the present study was to investigate the effectiveness of a regenerative procedure based on supracrestal soft tissue preservation in association with enamel matrix proteins (EMP) in the treatment of deep intrabony defects.

METHODS

The subjects included 35 consecutively treated patients, 23 females and 12 males, aged 28-61 years, 11 of whom were smokers. Patients presented with at least one intrabony defect with probing pocket depth > or = 6 mm and a radiographic depth of the defect > or = 4 mm at the initial visit. Immediately before surgery and 9-12 months after surgery, Local Plaque Score (LPS), Local Bleeding Score (LBS), probing pocket depth (PPD), clinical attachment level (CAL), gingival recession (REC), and radiographic depth of the defect (DEPTH) were recorded.

RESULTS

Thirty-one (88.6%) defects were LPS-negative presurgery, while 29 (82.9%) defects presented with no plaque postsurgery. The prevalence of LBS-positive defects shifted from 94.3% presurgery to 8.4% postsurgery (p < 0.0000). PPD was 8.9 mm before surgery, and decreased to 3.5 mm postsurgery (p < 0.0000). CAL varied from 10.1 mm presurgery to 5.4 mm postsurgery (p < 0.0000), with an average improvement (gain) of 4.7 +/- 1.7 mm. Twenty-six (74.3%) defects presented a gain of least 4 mm. Regression analysis showed a positive correlation between CAL gain as a dependent variable, and presurgery PPD and amount of supracrestal soft tissues as predictors. DEPTH improvement (gain) was 3.9 +/- 1.8 mm, which represented 65% of defect fill. Twenty (57.1%) defects presented a DEPTH gain of at least 4 mm. DEPTH gain was significantly correlated to presurgery PPD (p < 0.000). No significant differences were found between smokers and non-smokers in terms of CAL and DEPTH gain.

CONCLUSIONS

Results from the present study indicated that the regenerative procedure based on supracrestal soft tissue preservation and EMP application leads to clinically and statistically significant improvement of hard and soft tissue conditions of deep intrabony defects.

Cellular dermal matrix used for root coverage: 18-month follow-up observation

The goal of this study was to evaluate the long-term stability of the root coverage results obtained with an acellular dermal matrix. The mean root coverage at 12 weeks postoperative was 91.7%. The mean root coverage at the final postoperative evaluation (mean 18.6 months) was 87.0%. This difference was not statistically or clinically significant. The root coverage results obtained with an acellular dermal matrix were predictable, esthetic, and stable over time.

Comparison of platelet-rich plasma, bovine porous bone mineral, and guided tissue regeneration versus platelet-rich plasma and bovine porous bone mineral in the treatment of intrabony defects: a reentry study

BACKGROUND

A combination of platelet-rich plasma (PRP), bovine porous bone mineral (BPBM), and guided tissue regeneration (GTR) has been shown to be effective in promoting reduction in probing depth, gain in clinical attachment, and defect fill in intrabony periodontal lesions. The individual role played by PRP, BPBM, and GTR in this combined therapy is unclear and needs to be elucidated. The purpose of this study was to compare the clinical effectiveness of 2 regenerative techniques for intrabony defects in humans: a combination of PRP/BPBM/GTR versus a combination of PRP/BPBM.

METHODS

Twenty-one patients participated in the study. Using a split-mouth design, interproximal bony defects were surgically treated with either a combination of PRP/BPBM/GTR or PRP/BPBM. The primary outcomes of the study included changes in probing depth, attachment level, and defect fill as revealed by reentry surgeries at 6 months post-treatment.

RESULTS

At 6 months postoperatively, clinical examination of the treated defects revealed that both treatment modalities resulted in significant probing depth reduction and clinical attachment gain compared to baseline values. Probing depth improvement was 3.98 +/- 1.02 mm on buccal and 3.94 +/- 0.94 mm on lingual sites for the PRP/BPBM group and 4.19 +/- 0.88 mm on buccal and 4.21 +/- 0.92 mm on lingual sites for the PRP/BPBM/GTR group. Gain in clinical attachment was 3.78 +/- 0.72 mm on buccal and 3.84 +/- 0.76 mm on lingual sites for the PRP/BPBM group and 4.12 +/- 0.78 mm on buccal and 4.16 +/- 0.83 mm on lingual sites for the PRP/BPBM/GTR group. Reentry surgeries revealed similar defect fill for both treatment groups (PRP/BPBM group: 4.82 +/- 1.34 mm on buccal and 4.74 +/- 1.30 mm on lingual sites; PRP/BPBM/GTR group: 4.96 +/- 1.28 mm on buccal and 4.78 +/- 1.32 mm on lingual sites). None of the differences between the 2 treatment groups was statistically significant.

CONCLUSIONS

The results of this study show that both combinations of PRP/BPBM/GTR and PRP/BPBM are effective in the treatment of intrabony defects present in patients with advanced chronic periodontitis. The results also suggest that GTR adds no clinical benefit to PRP/BPBM. Further studies are necessary to assess the individual role played by PRP and BPBM in the clinical outcome achieved with their combination.

Computer assisted image analysis methods for evaluation of periodontal wound healing

The aims of this study were to determine the accuracy of the computer assisted image analysis method and to evaluate its application for the assessment of periodontal wound healing in dogs. Histological material was analyzed with an optic microscope connected to a CCD color camera which transmitted the image to a frame grabber converting the light signals into pixels from which the measurements could be obtained. Twenty sections were read to assess the intra- and inter-examiner reproducibility for the parameters of area filled by new tissue, area of epithelium, area of bone and linear measurements of the cementum. The data were statistically analyzed using the t-test to test the hypothesis that there was no difference between and within examiners. No statistically significant differences were noted (with a confidence interval of 95%) for any parameter when intra-examiner reproducibility was assessed. Similar results were achieved for surface areas when the inter-examiner readings were computed. However, values of linear measurements for cementum showed statistically significant differences between recorders (p < 0.05). Results were consistently uniform and the method demonstrated high accuracy when intra-examiner readings were evaluated.

GCF IL-1beta profiles in periodontal disease

OBJECTIVES

Studies suggest a genetic influence on levels of interleukin-1beta (IL-1beta) in gingival crevicular fluid (GCF). Levels of IL-1beta in GCF, however, are also dependent upon the clinical parameters at the site of collection, including probing depth (PD) and level of attachment (AL). To examine this issue, IL-1beta in GCF was evaluated from patients with varying degrees of periodontal disease. The influence of both the status of the patient and the probing depth at the sampled sites were considered in the analysis.

MATERIAL AND METHODS

GCF IL-1beta was determined by ELISA at 6-8 molar sites from 29 non-smoking adults with mild, moderate, or severe periodontal disease at baseline, 2 weeks, and 24 weeks following scaling and root planing. For later analysis, patients were dichotomized on the basis of disease severity (mild/moderate vs severe). Sampled sites were classified at baseline by PD as, shallow (<4 mm), intermediate (4-6 mm), or deep (>6 mm).

RESULTS

PD and AL were each strongly correlated with IL-1beta levels at baseline. However, patients with severe disease had higher levels of IL-1beta in each PD category than those with mild/moderate disease. As compared to patients with mild/moderate disease, IL-1beta levels in shallow sites from patients with severe disease was elevated nearly 2 fold (p<0.001). IL-1beta levels were reduced in all groups at 2 weeks and were still significantly reduced in patients with mild/moderate disease at 24 weeks. At 24 weeks IL-1beta returned to near baseline levels in patients with severe disease.

CONCLUSION

While PD and AL are each associated with increased GCF IL-1beta, patients with severe disease show higher IL-1beta GCF levels in shallow sites, suggesting that high GCF IL-1beta expression is in part a host trait, and not strictly a function of clinical parameters.

Comparative evaluation of surgical and conservative treatment modalities of juvenile periodontitis patients

In a comparative evaluation of the effectiveness of two treatment modalities for juvenile periodontitis, 12 patients aged between 15 years and 23 years were recruited into a six months longitudinal study. The split mouth design was used such that one side (upper and lower quadrants) received conservative treatment. Each side was randomly assigned one of the two treatment modalities. Standardized probing attachment level (PAL) measurement and degree of mobility of the teeth were taken at recruitment (baseline), one, three and six months postoperation. Tetracycline capsules 250mg, 6 hourly, was administered for 2 weeks at baseline and at 3 months follow-up. Initial thorough scaling and polishing of the whole mouth was done for all the patients. At follow-up, there were marked improvements seen with both treatment modalities. The mean probing depth for surgical treatment (3.57mm +/- 0.78) was significantly lower than that of conservative treatment (4.11mm +/- 0.74) P < 0.05 at 3 months. Also, this significant difference continued up to 6 months (2.70mm +/- 0.57, 3.55mm +/- 0.65; P < 0.05 ). For the degree of mobility, significant difference was only evident at 6 months of follow-up (0.48 +/- 0.29, 0.98 +/- 0.523; P < 0.05 ) for surgical treatment and conservative treatment respectively. It was therefore concluded that surgical debridement with systemic administration of tetracycline is more effective than the conservative technique in the treatment of juvenile periodontitis, although both gave improvement.

Mandibular second molar periodontal status after third molar extraction

BACKGROUND

Extraction and treatment of third molars have been cited as causing periodontal problems. To evaluate the long-term effects of third molar extraction on the periodontal health of the mandibular second molar, a comparison of the periodontal status was performed around 2 groups of mandibular second molars, with and without third molar extraction.

METHODS

A total of 312 sites in 57 adult periodontitis patients were examined and the buccal and lingual locations of the mesial and distal root surfaces around the second molars were recorded. Two-hundred and thirty-two sites were experimental teeth; i.e., third molars had been surgically removed more than 5 years ago, 80 sites served as control molars; i.e., congenitally missing third molars. Clinical periodontal parameters including probing depth, attachment loss, and gingival recession and radiographic intrabony level were measured. The effects of the surgery and the examination (buccal or lingual) locations on the measurements were statistically analyzed.

RESULTS

Neither extraction history nor examination location affected the probing depth on mesial surfaces. However, significant effects of the surgical history on the probing depth were observed on the distal surfaces. Similar results of greater attachment loss and radiographic alveolar bone loss were observed only at the distal sites of the experimental group. In addition, the increased radiographic bone loss was only found at the distal sites (adjacent to the surgical location) and not at the mesial sites (distant from the surgical location) on the experimental group.

CONCLUSIONS

In this study, greater periodontal breakdown, including probing depth, attachment loss, and radiographic alveolar bone loss, was found at the distal sites, but not at the mesial sites, of the experimental molars where the third molar was surgically extracted compared with the control teeth (no surgery). In the experimental molars, more radiographic bone loss was found at the sites adjacent to the surgical location than at the sites distant to the surgical location. Therefore, we suggest that the surgical removal of the mandibular third molar may lead to a periodontal breakdown on the distal surface of the second molar. Periodontal re-evaluation after the initial healing of third molar extraction is indicated.

Root coverage and pocket reduction as combined surgical procedures

BACKGROUND

One of the main objectives of periodontal reconstructive surgery is the coverage of exposed roots due to gingival recession. A large variety of mucogingival grafting procedures are available that give highly predictable and esthetically acceptable results when treating intact root surfaces. However, these procedures call for a second surgery site in the palate. The present study examines a series of cases in which connective tissue, obtained from the tuberosity during pocket reduction procedures in the posterior region of the maxilla, was used for root coverage.

METHODS

Forty-four teeth from 25 patients with gingival recession of 3.30 +/- 0.14 mm (mean +/- SEM) were treated with subepithelial connective tissue grafts using connective tissue obtained from the tuberosity area during pocket reduction procedures in the posterior region of the maxilla.

RESULTS

The mean root coverage recession after treatment was 0.16 +/- 0.06 mm, with effectiveness of coverage at 95.0% +/- 1.84 and a predictability of 84.1%. Periodontal probing depth reduction at the donor site was 4.08 +/- 0.24 mm.

CONCLUSIONS

These results indicate that the subepithelial connective tissue graft obtained from the tuberosity area during pocket reduction procedures in the posterior region of the maxilla provides a very predictable and esthetic root coverage without the need for a second surgical site.

Comparative 6-month clinical study of a subepithelial connective tissue graft and acellular dermal matrix graft for the treatment of gingival recession

BACKGROUND

Different techniques have been proposed for the treatment of gingival recessions. This study compared the clinical results of gingival recession treatment using a subepithelial connective tissue graft and an acellular dermal matrix allograft.

METHODS

Nine patients with bilateral Miller Class I or II gingival recessions were selected. A total of 30 recessions were treated and randomly assigned to the test group and the contralateral recession to the control group. In the control group, the exposed root surfaces were treated by the placement of a connective tissue graft in combination with a coronally positioned flap; in the test group, an acellular dermal matrix allograft was used as a substitute for palatal donor tissue. Probing depth, clinical attachment level, gingival recession, and width of keratinized tissue were measured 2 weeks prior to surgery and 3 and 6 months postsurgery.

RESULTS

There were no statistically significant differences between the test group and the control group in terms of recession reduction, clinical attachment gain, and reduction in probing depth. The control group had a statistically significant increased area of keratinized tissue after 3 months compared to the test group. Both procedures, however, produced an increase in keratinized tissue after 6 months, with no statistically significant difference.

CONCLUSION

The acellular dermal matrix allograft may be a substitute for palatal donor tissue in root coverage procedures.

Comparison of 2 clinical techniques for treatment of gingival recession

BACKGROUND

In early case studies, use of a collagen barrier as a guided tissue regeneration (GTR) material has shown particular promise in procedures aimed at root coverage. The similarities between collagen membrane and subepithelial connective tissue graft (SCTG) have made collagen membrane an attractive and a possible alternative material for root coverage. The purpose of this randomized clinical trial was to compare these 2 techniques, SCTG versus a GTR-based procedure (GTRC), for root coverage/recession treatment.

METHODS

Sixteen patients with bilateral Miller's Class I or II (gingival recession > or = 3.0 mm) recession defects were treated either with SCTG or GTRC using a newly designed collagen membrane. Clinical parameters monitored included recession depth (RD), clinical attachment level (CAL), probing depth (PD), width of keratinized gingiva (KG), attached gingiva (AG), and recession width (RW), each measured at the mid-buccal area to the nearest 0.5 mm. Measurements were taken at baseline and 6 months. A standard mucogingival surgical procedure was performed. Data were reported as means +/- SD and were analyzed using the paired t test for univariate analysis and restricted/residual maximal likelihood (REML)-based mixed effect model for multivariate analysis.

RESULTS

No statistically significant differences were observed in RD, CAL, KG, and AG between test and control groups at either time period. However, SCTG showed significantly more residual PD and more RW gain when compared to GTRC at 6 months. Both treatments resulted in a statistically significant (P < 0.05) reduction of recession defects (2.5 mm and 2.8 mm), gain of CAL (2.8 mm and 2.3 mm), reduction of RW (1.9 mm and 2.7 mm), and increase of KG (0.7 mm and 1.1 mm) and AG (0.7 mm and 0.5 mm) for GTRC and SCTG, respectively, when comparing 6-month data to baseline. Mean root coverage of 73% (collagen membrane) and 84% (subepithelial connective tissue graft) was achieved.

CONCLUSIONS

The 2 techniques are clinically comparable. Use of a modified collagen membrane to attain root coverage may alleviate the need for donor site procurement of connective tissue.

Prevalence and extent of lifetime cumulative attachment loss (LCAL) at different thresholds and associations with clinical variables: changes in a population of young male military recruits over 3 years

AIM

The aims of this study were to monitor the prevalence and progression of lifetime cumulative attachment loss (LCAL) in a group of young British male military recruits over a 3-year period, and to determine the relationship between signs of LCAL and selected periodontal variables.

METHODS

100 subjects, aged 16-20 years (mean 17 years) at baseline, were examined at 0 (baseline), 12 and 30 months. LCAL, probing depth, plaque, bleeding on probing, gingival colour and supra- and subgingival calculus were assessed on the mesio-buccal, disto-buccal, mesio-lingual and disto-lingual surfaces of all teeth present, excluding third molars. Data were analysed cross-sectionally at each examination.

RESULTS

Over the period of the study, the prevalence of LCAL > or =1 and 2 mm ranged from 95-100%, whereas LCAL > or =3 mm ranged from 40-47%. The extent of LCAL > or =1 mm ranged from 76-86%. However, the extent of LCAL > or =2 mm was dramatically lower (10.5-12.7%), and LCAL > or =3 mm was uncommon (0.5-0.9%). Examining the number of subjects according to the number of sites affected above a threshold, showed that a small number of subjects have a large number of sites above threshold. Using Pearson's rank correlation coefficient a significant correlation (p<0.05) was found between LCAL and the periodontal variables of gingival bleeding and supra- and subgingival calculus.

CONCLUSIONS

These data suggest that the onset and progression of chronic periodontitis can be seen in young adults, and in this group gingival bleeding and supra- and subgingival calculus are the variables most strongly associated with early periodontitis.

Cell-surface proteoglycan expression by lymphocytes from peripheral blood and gingiva in health and periodontal disease

Cell-surface proteoglycans are involved in lymphocyte migration and activation. This study investigated the expression of syndecan-1, syndecan-4, and glypican in peripheral blood lymphocytes and by lymphocytes in variously inflamed periodontal tissues. Gingival specimens from healthy, gingivitis, or chronic periodontitis sites were stained by means of antibodies against B- and T-lymphocytes and also syndecan-1, syndecan-4, and glypican. Syndecan-1 expression by peripheral blood mononuclear cells (PBMC) from healthy, gingivitis, and chronic periodontitis subjects was assessed by flow cytometry. Syndecan-1 was expressed by B-cells/plasma cells but not T-cells in both gingivitis and chronic periodontitis lesions. Both B-cells/plasma cells and T-cells in gingivitis and chronic periodontitis expressed syndecan-4. Glypican was expressed only by macrophages. Stimulation of PBMC with mitogens and growth factors modulated syndecan-1 expression in both the T- and B-cells. Thus, cell-surface proteoglycan expression by lymphocytes in periodontal inflammation is cell-type-specific and may be modulated by inflammation.

Histologic assessment of healing after the use of a bioresorbable membrane in the management of buccal bone loss concomitant with periradicular surgery

Histological and morphometric assessment of periradicular wound healing was made after the use of a bioresorbable membrane over a buccal dehiscence. The third and fourth premolar teeth of nine dogs were resected and buccal defects created. Teeth were assigned randomly to the membrane or control group. One tooth in each quadrant received a membrane, covering both roots. The other tooth received no further treatment and served as a control. The animals were killed and specimens were assessed at two time periods: 9 wk and 27 wk. The 27-wk membrane group exhibited significantly more (p = 0.004) connective tissue height than the control group or either of the 9-wk groups. The amount of regenerated alveolar bone was significantly greater for the 27-wk membrane group than for the control (p = 0.001) and 9-wk groups. Mean junctional epithelium measurements were significantly greater (p = 0.012) for the control. The use of a bioresorbable membrane enhances bone regeneration when a buccal defect exists at the time of periradicular surgery.

Characterization of cellular infiltrate, detection of chemokine receptor CCR5 and interleukin-8 and RANTES chemokines in adult periodontitis

Leukocyte migration is essential for immune surveillance of tissues by focusing immune cells to sites of antigenic challenge. The control of leukocyte migration depends on the combined actions of adhesion molecules and a vast array of chemokines and their receptors. The purpose of the present study was to investigate the involvement of Interleukin-8 (IL-8), RANTES, the associated infiltrating cells and expression of CCR5 chemokine receptors in periodontitis; furthermore, the effect of periodontal therapy on these parameters was evaluated. Patients included in the study had moderate to advanced periodontal disease with at least 5-6 teeth with probing depth > 6 mm, attachment loss > or =3 mm and extensive radiographic bone loss. The inflammatory infiltrate was analyzed by immunohistochemistry in gingival biopsies obtained from subjects at the beginning of the study and 2 months after periodontal treatment. Gingival crevicular fluid (GCF) was collected for 30 seconds using periopaper strips, and chemokines were quantified by ELISA. The cellular components of the inflammatory infiltrate included B (CD19) and T (CD3, CD4+ and CD8+) lymphocytes and monocytes/macrophages (CD11c). CCR5 chemokine receptor expressing cells were exclusively found in periodontitis gingiva. IL-8 and RANTES were detected in the periodontitis group, obtaining a total amount of 212.5 pg and 42.0 pg, respectively. However, IL-8 was also detectable in the GCF of the healthy group (total amount of 44.8 pg). Periodontal therapy reduced the cell number in the infiltrate and the levels of IL-8 and RANTES, suggesting a relationship between these chemokines and periodontal status. We propose that the presence of these chemokines and the expression of chemokine receptors may represent a marker of lymphocyte subsets with the ability to migrate to inflammatory sites.

Tooth loss in periodontal patients

OBJECTIVE

To compare tooth loss between patients who received surgical therapy for chronic periodontitis and those who received nonsurgical therapy alone.

METHODS

A retrospective chart study was conducted at Dalhousie University. All patients who had periodontal treatment and were active cases for at least 10 years were included (n = 335). The sample consisted of 120 males (35.8%) and 215 females (64.2%). Ages ranged from 16 to 77 (mean = 46.1 +/- 12.0 years). All patients received nonsurgical therapy; 44.8% received periodontal surgery as well. Variables recorded were demographics, initial attachment loss, treatment type, recall frequency, patient compliance and history of extracted teeth. Independent t-tests or chi-squared tests were used to compare these for surgical and nonsurgical patients. ANOVA was used to test for interactions between initial attachment loss, age, gender, compliance and type of therapy a patient received as reasons for tooth loss.

RESULTS

521 teeth were lost in 69 patients (20.6% of sample). Of teeth lost, 61.8% were due to periodontal disease; 24.8% to caries; 13.2% to other reasons. Patients initially diagnosed with early attachment loss lost an average of 0.37 (+/- 1.33) teeth. Patients diagnosed with moderate attachment loss lost an average of 1.50 (+/- 2.54) teeth and those diagnosed with advanced attachment loss lost an average of 3.11 (+/- 3.01) teeth. Those who received surgical therapy lost more teeth (mean = 1.31 +/- 2.36) than those who received nonsurgical treatment (mean = 0.68 +/- 1.87; p = 0.001). However, initial attachment loss was the only factor that could predict tooth loss. The type of therapy (surgical or nonsurgical) was not statistically significant.

CONCLUSIONS

Most periodontal patients (79.4%) who received treatment at this dental school clinic did not lose any teeth due to periodontal disease over at least 10 years. Although patients who had surgical therapy lost more teeth than those who had nonsurgical therapy alone, this was not an important predictor of tooth loss.

Clinical evaluation of anorganic bovine bone xenograft with a bioabsorbable collagen barrier in the treatment of molar furcation defects

The purpose of this study was to compare Bio-Oss (BO), an anorganic bovine bone xenograft, in combination with Bio-Gide (BG), a bioabsorbable collagen barrier, to open-flap debridement (OFD) surgery in human mandibular Class II furcation defects. A total of 31 furcations (18 treatment, 13 control) in 21 patients were treated. There was a statistically significant improvement in most clinical indices for the BO/BG group, with minimal improvement noted for the OFD group. Vertical probing depth reduction of 2.0 mm and horizontal probing depth reduction of 2.2 mm were noted for the BO/BG group, with 0.3 mm and 0.2 mm reductions, respectively, noted for OFD. Hard tissue measurements showed 2.0 mm of vertical furcation bone fill for BO/BG and 0.5 mm for OFD. The BO/BG group had 3.0 mm of horizontal furcation bone fill, and the OFD group had 0.9 mm. The BO/BG group had a defect resolution of 82.7%; 42.5% was noted for the OFD group. There was a statistically significant difference between BO/BG and OFD in all soft and hard tissue measurements with the exception of attachment level, recession, and alveolar crest resorption.

Periodontal regeneration with an autogenous bone-Bio-Oss composite graft and a Bio-Gide membrane

This study evaluated the clinical, radiographic, and histologic response to the composite use of Bio-Oss porous bone mineral and autogenous bone in combination with a Bio-Gide bilayer collagen membrane to achieve regeneration when treating human periodontal bone defects. Preoperative recordings for four treatment areas included radiographs, clinical probing depths, and attachment levels; these recordings were repeated at 9 months. Histologic evaluation revealed new cementum with inserting collagen fibers and new bone formation on the surface of both types of graft materials. This grafting combination not only compared favorably with the previous use of Bio-Oss and Bio-Gide, but exceeded that result with almost complete periodontal regeneration. This human histologic study demonstrates that autogenous bone in combination with porous bone mineral matrix, together with the Bio-Gide collagen membrane, has the capacity to stimulate substantial new bone and cementum formation with Sharpey's fiber attachment.

Relationship of cigarette smoking to attachment level profiles

OBJECTIVES

The present investigation examined clinical features of periodontal disease and patterns of attachment loss in adult periodontitis subjects who were current, past or never smokers.

MATERIAL AND METHODS

289 adult periodontitis subjects ranging in age from 20-86 years with at least 20 teeth and at least 4 sites with pocket depth and/or attachment level >4 mm were recruited. Smoking history was obtained using a questionnaire. Measures of plaque accumulation, overt gingivitis, bleeding on probing, suppuration, probing pocket depth and probing attachment level were taken at 6 sites per tooth at all teeth excluding 3rd molars at a baseline visit. Subjects were subset according to smoking history into never, past and current smokers and for certain analyses into age categories <41, 41-49, >49. Uni- and multi-variate analyses examined associations between smoking category, age and clinical parameters.

RESULTS

Current smokers had significantly more attachment loss, missing teeth, deeper pockets and fewer sites exhibiting bleeding on probing than past or never smokers. Current smokers had greater attachment loss than past or never smokers whether the subjects had mild, moderate or severe initial attachment loss. Increasing age and smoking status were independently significantly related to mean attachment level and the effect of these parameters was additive. Mean attachment level in non smokers <41 years and current smokers >49 years was 2.49 and 4.10 mm respectively. Stepwise multiple linear regression indicated that age, pack years and being a current smoker were strongly associated with mean attachment level. Full mouth attachment level profiles indicated that smokers had more attachment loss than never smokers particularly at maxillary lingual sites and at lower anterior teeth.

CONCLUSIONS

In accord with other studies, smokers had evidence of more severe periodontal disease than past or never smokers. At all levels of mean attachment loss, smokers exhibited more disease than never smokers. Difference in mean attachment level between smokers and never smokers at individual sites was not uniform. Significantly more loss was observed at maxillary lingual sites and lower anterior teeth suggesting the possibility of a local effect of cigarette smoking.

Apoptosis in chronic adult periodontitis analyzed by in situ DNA breaks, electron microscopy, and immunohistochemistry

BACKGROUND

Apoptosis is an evolutionary form of physiological cell death. Previous studies suggest that apoptosis is involved in the pathogenesis of periodontal diseases. Therefore, we studied the apoptotic events in the gingival tissue of chronic adult periodontitis patients.

METHODS

Gingival tissue biopsies from 22 patients with chronic adult periodontitis and from 11 healthy controls were obtained. Criteria for patient inclusion in the periodontitis group were a minimum of 14 natural teeth, excluding third molars, with at least 10 posterior teeth; 5 to 6 sites with probing depth > or = 5 mm; attachment loss > or = 3 mm; and extensive radiographic bone loss. The control group included healthy subjects with no prior history of periodontal disease. Apoptosis was determined using the terminal TdT-mediated dUTP-biotin nick end labeling (TUNEL) technique; electron microscopic analysis; and expression of Caspase-3, Fas, FasL, Bcl-2, and p53 by immunohistochemistry.

RESULTS

TUNEL-positive cells and cells exhibiting chromatin condensation by electron microscopy were observed in the inflammatory infiltrate of biopsies obtained from periodontitis patients. Most of the TUNEL-positive cells belonged to neutrophil cell populations as they were stained with anti-myeloperoxidase. Positive staining for active-caspase 3, Fas, FasL, and p53 was only observed in the inflammatory infiltrate from periodontitis biopsies, whereas Bcl-2 cells were present in both periodontitis patients and healthy controls.

CONCLUSIONS

Our findings establish that apoptosis is induced in the periodontal tissue by host and microbial factors and support the hypothesis that apoptotic mechanisms could be implicated in the inflammatory process associated with gingival tissue destruction observed in adult periodontitis patients.

Is loss of attachment due to root planning and scaling in sites with minimal probing depths a statistical or real occurrence?

BACKGROUND

Following root planing and scaling many studies have implied an association between a loss of clinical attachment at sites with initially shallow pockets (1 to 3 mm) and gains in attachment level for deeper probing depths. However, these effects are also consistent with a statistical phenomenon referred to as regression towards the mean. This principle suggests that extreme values will moderate the next time they are recorded. The purpose of this report was to estimate the effect that regression towards the mean has on perceived changes in attachment level after root planing and scaling.

METHODS

During the initial examination, 2 different investigators conducted 2 full-mouth probings. Two quadrants were randomly selected to be root planed and scaled until the root surfaces were smooth by tactile touch of an explorer. The 2 remaining quadrants were not treated. At 4 to 6 weeks after treatment, another full mouth probing was done. An examiner who was blind to the quadrants that had been scaled measured attachment level and probing depth after therapy. This study design provided periodontal measurements before and after root planing and scaling, measurements before and after a period of 4 to 6 weeks of no therapy, and duplicate measurements at the beginning of the study.

RESULTS

Using the repeat examination when no true change could occur, shallow sites (< or =3 mm of probing depth) showed average negative differences between repeat attachment level measurements (-0.23 mm), which mimicked loss of periodontal attachment. Deep sites, (>6 mm) showed average positive values (0.40) mimicking gain in attachment level. These results suggest that regression towards the mean is a significant effect in this data set. Both shallow non-scaled and scaled sites had similar differences in repeat measures (-0.28 mm, -0.25 mm) which were also similar to and not statistically different from changes after therapy for both non-scaled (-0.21 mm) and scaled sites (-0.08 mm). Thus not only does this data set exhibit regression towards the mean, but it explains the majority of perceived loss of periodontal attachment after scaling at sites that have minimal probing depth.

CONCLUSIONS

These results suggest that the majority of perceived loss of attachment due to scaling at sites of minimal probing depth that have been reported in many studies may be due a statistical phenomenon called regression towards the mean.