Outcome variables for the study of periodontal regeneration

The most reliable outcome variable for assessing periodontal regeneration is human histology; however, the morbidity associated with this technique makes it feasible only in isolated case studies designed to prove that a drug, device, or technique is capable of regenerating the lost periodontium including bone, cementum, and functionally oriented periodontal ligament. In the absence of this genuine variable, other "surrogate" variables must be used. Of these, measurement of new bone is the primary alternative. Direct bone measurements, including linear and volumetric assessment, are by far the best tools; however, the need for a second surgical procedure is a definite drawback of this technique. To overcome this problem, other outcomes have been employed: sounding bone measurements is a less invasive method, albeit it is also less accurate. Another tool that has been tested extensively is radiographic analysis. Conventional radiography is not useful in most regenerative trails where minimal or no crestal changes occur. The use of standardized radiographs and image processing techniques to measure alveolar bone changes has not significantly enhanced the applicability of this method. Digital subtraction radiography (DSR) offers some improvement over previous techniques; however, the correlation between the magnitude of clinical bone changes and changes in the digital image is yet to be substantiated. Other variables have been successfully used in regenerative studies. These include clinical attachment level changes, change in probing depth, and gingival recession. The information derived from these variables, especially attachment level changes, supplement and substantiate the direct bone measurements. Other variables that may be monitored are those associated with plaque formation, periodontal pathogens and gingival inflammation; while not direct measures of regeneration, these variables are likely to affect future prognosis and treatment stability. In summary, direct bone measurements are the most ideal surrogate outcome variable, although clinical attachment level measurements are commonly used in large-scale regenerative clinical trials. Clinical response may be assessed at different time intervals; however, the endpoint measurements for regenerative studies should be taken at least 12-months postoperatively.     

Role of intestinal transit in the pathogenesis of gallbladder stones

The aim of the study was to compare the occurrence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia in the subgingival plaque from sites with and without early periodontitis in adolescents using an ELISA. 47, 15- to 16-year-old adolescents (39 Indo-Pakistani, 8 white Caucasian) were examined for clinical attachment level, probing depth, supragingival plaque, subgingival calculus and bleeding on probing on the mesio-buccal and disto-buccal aspects of the 1st molars and the incisors. Based on the clinical data, 2 sites per subject were selected for subgingival plaque sampling 3 weeks later: in 32 subjects with loss of attachment > or = 1 mm, a diseased site (D) and a healthy comparison control site (C) were sampled; in 15 subjects in whom loss of attachment had not yet developed, 1 of the upper molar sites was selected, called the at-risk site (R), together with a C site. The presence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia were determined using an ELISA. The loss of attachment subgroup had significantly more pockets > or = 4 mm, subgingival calculus and bleeding on probing (p < 0.05). Significantly more of the D than C sites had P. gingivalis both at detectable and at measurable levels (p < 0.05). In subjects who had no loss in clinical attachment levels, fewer sampled sites harboured any of the suspected periodontopathogens investigated, and no significant differences were found between the R or C sites (p > 0.05). Although there was a significantly higher prevalence and extent of loss of attachment > or = 1 mm in the Indo-Pakistani subjects compared with the Caucasians (p < 0.05), no differences could be identified in the distribution of the bacteria. It is concluded that monitoring of the subgingival plaque may be useful in studies of early periodontitis in adolescents, and the role of P. gingivalis needs to be elucidated in prospective longitudinal investigations.     

A relationship between proteinase activity and clinical parameters in the treatment of periodontal disease

The objective of this research was to determine the effectiveness of a biochemical assay which measures proteolytic enzyme activity in gingival crevicular fluid (GCF) and to relate this enzyme activity to clinical parameters traditionally utilized for periodontitis detection. A clinical trial was conducted on 8 periodontitis subjects with > or =4 sites exhibiting a loss of attachment of > or =5 mm and probing depths of > or =5 mm with bleeding on probing. On each subject, a plaque index was performed, followed by GCF sampling at those sites which exhibited a loss of attachment and probing depths. GCF was analyzed for activity against benzoyl-L-arginine-p-nitroanilide in the presence (BAPNA w/gly-gly) and the absence (BAPNA w/o gly-gly) of glycyl-glycine and against MeOSuc-Ala-Ala-Pro-Val-pNA and Suc-Ala-Ala-Pro-Phe-pNA for neutrophil serine proteinases activity (elastase and cathepsin G, respectively). Subsequently, a gingival index was performed, attachment levels and probing depths were recorded using a constant force probe with bleeding on probing being noted. A split-mouth design was employed and half mouths were randomly assigned to the following treatment groups: group A, half of the mouth received scaling/root planing and polishing: group B, half of the mouth received no treatment (control). Subjects were treated, then instructed on toothbrushing and interdental cleaning. After 4 weeks, subjects returned to receive a plaque index; GCF sampling, gingival index, attachment levels, probing depths and bleeding on probing as described above. Using a paired Student t-test, the findings suggest that BAPNA w/gly-gly was significantly less in treatment sites than in non-treated control sites (p=0.05). No such correlation was found for other activities, including neutrophil serine proteinases which were shown to occur in GCF in free, proteolytically active forms. In addition, significant treatment effects were detected for probing depths (p= 0.03) which reduced by 1.3 mm and attachment levels (p=0.02) which gained 0.7 mm. The reduction of P. gingivalis from treated periodontitis sites as detected by a significant decrease in BAPNA w/ gly-gly may prove to be a valuable marker for periodontal disease activity.     

The prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus in humans 1 year after 4 randomized treatment modalities

The relationship between probing attachment changes in treated periodontal pockets and the prevalence of selected periodontal pathogens was assessed in 10 patients with adult periodontitis 1 year following randomized therapy. All patients had at least 1 tooth in each quadrant with an inflamed pocket of probing depth > or =5 mm and clinical attachment loss and harbored at least one of the following 3 major periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, or Bacteroides forsythus. The number of target organisms per site was determined preoperatively; at 1 week; and at 1, 3, 6, and 12 months postoperatively utilizing DNA probes. The following clinical parameters were measured and recorded preoperatively and at 1, 3, 6, and 12 months post-treatment: gingival fluid flow, gingival index, plaque index, probing depth, probing attachment level, gingival recession, and bleeding on probing. One quadrant in each patient was randomly assigned to 1 of the following 4 treatments: 1) scaling and root planing; 2) pocket reduction through osseous surgery and apically-positioned flap; 3) modified Widman flap; and 4) modified Widman flap and topical application of saturated citric acid at pH 1 for 3 minutes. All 4 treatments were rendered in one appointment using local anesthesia. No postoperative antibiotics were used, but patients rinsed with 0.12% chlorhexidine for the first 3 months postoperatively and received a prophylaxis every 3 months. This investigation revealed: 1) 30.0% of the sites were infected by at least 1 species at 3, 6, and 12 months postoperatively. 2) Failing sites were infected by a high number of both Pg and Bf These sites had a mean of 24.2+/-9.0 x 10(3) Pg and 93.1+/-42.0 X 10(3) Bf while stable sites had a mean of 6.8+/-0.5 x 10(3) Pg and 7.2+/-1.2 x 10(3) Bf (P = 0.06 and P = 0.05, respectively). 3) The infected sites lost significantly more mean clinical attachment at 12 months (1.5+/-0.5 mm compared to a loss of 0.2+/-0.3 mm for uninfected sites, P = 0.017). 4) The infected sites had a significantly greater BOP (67+/-14% versus 25+/-8% for uninfected sites at 12 months, P = 0.012). 5) The choice of treatment modality did not affect the prevalence of the target species at 1 year post-treatment. These results suggest that prevalence of microbial pathogens negatively affects the 1 year outcome of periodontal surgical and nonsurgical therapy.     

Informatics in the service of health, a look to the future

Recent studies have demonstrated that smoking is associated with periodontal destruction. The majority of these studies have focused on periodontal disease groups with moderate or severe periodontal destruction. Additionally, there have been few reports investigating the relationship between smoking and gingival recession. The goal of this report was to investigate the effect of smoking on periodontal destruction and recession in subjects with minimal or no interproximal attachment loss. This is a cross-sectional study of 142 non-smoking subjects and 51 smoking subjects. Subjects could have no more than one tooth with a site of interproximal attachment loss > or =2 mm. Subjects could, however, have attachment loss associated with recession. For three different methods of summarizing attachment loss measurements at a subject level, including average attachment loss, percentage of teeth with one site of 2 mm of attachment loss, and the percentage of teeth with one site of 5 mm of attachment loss, smoking subjects had approximately twice as much attachment loss than their non-smoking counterparts. Smoking subjects also had significantly greater recession (P < 0.05) [0.056+/-0.017 mm] than non-smoking subjects (0.025+/-0.005 mm). Recession sites occurred primarily on the facial surface of maxillary molars and bicuspids and mandibular central incisors and bicuspids. The results suggest a strong association between smoking and both attachment loss and recession in subjects who have minimal or no periodontal disease.     

Stress and coping behaviors of substance-abusing mothers

BACKGROUND: The guided regeneration of periodontal tissues demonstrated to represent a therapeutical technique with predictable results. It has been observed that different materials, used as regenerative membranes, offer very similar results. Unconventional materials too, like the rubber dam, seem to be useful in the guided tissues regeneration technique. The object of the present study has been to comparatively evaluate the effectiveness of Gore-Tex and rubber dam-made membranes in the therapy of intra-osseous periodontal defects. MATERIALS AND METHODS: Six patients with two similar intra-osseous defects, participated in the study; one defect has been treated using, during the surgical intervention, a Gore-Tex membrane, while the other has received, a fragment of sterile rubber dam membranes. The principal clinical parameters of the periodontal health (probing depth -PD- and attachment loss -AL-) has been evaluated in both the defects before and 6 months after the periodontal surgery. RESULTS AND CONCLUSIONS: The results have showed that there are not statistically significant differences (p > 0.05) in the healing of the intra-osseous defects treated by rubber dam or Gore-Tex. The conclusion is drawn that the rubber dam can represent a valid and cheap alternative to the materials traditionally used in the regenerative surgery of the periodontal tissues.     

Bone replacement grafts. The bone substitutes

Bone substitutes will play a pivotal role in the future of periodontal regeneration. They are synthetically derived or processed from exoskeletons of other species (xenograft) and are an alternative to autogenous or allogeneic bone replacement grafts. Bone substitutes do not provide the cellular elements necessary for osteogenesis, and they cannot be considered osteoinductive, but instead are osteoconductive, providing a scaffold for new bone deposition. Currently, significant decreases in clinical probing depth and attachment levels have been reported with bone substitutes when compared to flap debridement surgery alone for periodontal osseous defects. Reported differences among bone substitutes, autogenous grafts, and allograft materials, occur with respect to histologic outcomes. Overall, probing depth reduction and attachment level gains are similar for all bone replacement grafts.     

Crevicular fluid level of beta-glucuronidase in relation to clinical periodontal parameters and putative periodontal pathogens in early-onset periodontitis

Analysis of beta-glucuronidase (betaG) in the gingival crevicular fluid (GCF) provides an indication of neutrophil influx into the crevicular environment. The aim of this study was to test the hypotheses that: (1) betaG is significantly elevated in individuals with early-onset periodontitis (EOP) and that betaG activity correlates with disease severity; and (2) betaG level may reflect the local bacterial challenge in the gingival crevice. The study subjects consisted of a sub-sample of individuals examined in the National Survey of Oral Health of United States Children, which was undertaken during the 1986/87 school year. A total of 249 individuals were selected based on presence or absence of clinical attachment loss at baseline. The individuals were examined a second time 6 years later and the clinical attachment loss was assessed, and subgingival plaque and GCF were collected. The subjects were classified into 3 types of EOP and a control group. BetaG activity in the GCF and the levels of 7 putative micro-organisms in the pocket were assessed. The generalized EOP group had the highest betaG activity, followed by the localized and incidental EOP groups, and the controls, respectively. There was a significant increase in betaG activity with the increase in probing depth. Also, sites with bleeding on probing had a significantly higher betaG activity than sites without bleeding. However, the effect of gingival inflammation on betaG activity was more evident in the generalized and localized EOP groups. Sites harboring high levels of one or more of the micro-organisms tended to have high betaG activity. There were moderate differences between the organisms with respect to their effect on betaG activity, but sites with high numbers of Porphyromonas gingivalis, Prevotella intermedia, or Treponema denticola also had the highest betaG activity. The present findings suggest that betaG activity in GCF from patients with EOP can be of value in the early identification of individuals at higher risk of developing EOP The findings also suggest that host mechanisms leading to higher betaG activity in EOP represent systemic responses and are only partly related to the presence of local factors at the site-level.     

A clinical evaluation of guided tissue regeneration with a bioabsorbable matrix membrane combined with an allograft bone graft. A series of case reports

THE PURPOSE OF THIS STUDY was to evaluate the clinical effectiveness of a surgical technique in treating periodontal defects. The technique combined tetracycline treatment of a root planed root, grafting of the osseous defect with a demineralized freeze-dried bone allograft combined with tetracycline and the placement of a bioabsorbable matrix membrane, made of polylactic acid softened with citric acid ester. Thirty defects were treated in 27 patients. Statistically significant changes, as a result of the surgical procedure, were observed in marginal recession (mean: 0.5 mm), probing depth reductions (mean: 5.7 mm), and attachment level gain (mean: 5.2 mm). No statistically significant difference existed between the results in the furcation and non-furcation groups. The defects with probing depths > or = 10 mm had a greater mean probing depth reduction (7.4 mm) and mean attachment level improvement (7.2 mm) than the defects with < 10 mm probing depths (probing depth reduction 4.5 mm and attachment level gain 3.9 mm). The proposed surgical procedure seemed to be an effective method to treat periodontal defects.     

Lyme disease

A problem associated with probing measurement is that important site-specific change may be obscured by measurement variability. Furthermore, if many sites are monitored there is an increasing likelihood that any particular "detected change" might be the result of this measurement error. Since error and multiplicity effects would tend to increase mouth-wise false positive rate, demanding decision thresholds are often set. However, imposition of difficult criteria, increases site-wise false negative rate and therefore reduces utility in the clinical setting. Evaluation of mean change might sometimes be a useful alternative, but also problematic as a few dramatic site-level losses can be inconsequential among many stable or improving sites. A strategy is proposed for evaluating probing changes in a single patient, which is based on the statistical evaluation of two attributes of the change distribution. (1) Disease progression is concluded when mean probing loss increases over time, and (2) a clinically relevant asymmetry is concluded when the distribution tail corresponding to loss is skewed. Computerized simulation was used to determine alpha-error for tests of mean and skew, for three different distributions of probing change. Actual alpha-error was shown to be near nominal levels. Power was estimated as a function of the number and magnitude of sites with probing loss and as a function of whether there was change in both mean and skew or in skew alone. Under most conditions studied, simultaneous tests for skew and mean provided enhanced power relative to a test for loss alone and would appear to offer the clinician an additional statistical context for appraising disease status.     

Attachment to Parents and Psychological Well-Being: An Examination of Young Adult College Students in Intact Families and Stepfamilies.

Numerous studies have shown that compared to individuals from intact, biological families, individuals in stepfamilies tend to fare worse emotionally, socially, physically, and psychologically (e.g., Amato & Keith, 1991). Several studies have attempted to account for the discrepancy, but the research has not yielded definitive results. The current study evaluated attachment to parents as a possible explanation for discrepancies in psychological well-being. The results confirmed that attachment was a significant predictor of well-being. Additionally, individuals from stepfamilies were found to have less secure attachment to their parents than individuals from intact, biological families. Consistent with our hypothesis, we found that attachment (operationalized as maternal and paternal care) partially mediated the relationship between family type (intact, biological family vs. stepfamily) and psychological well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deliberate hypotension in head and neck surgery

The deliberate reduction of blood pressure in an attempt to reduce intraoperative blood loss has generated significant controversy in the 30 years since its clinical introduction. Numerous series have been reported, but few have met generally accepted, current criteria for controlled studies. In this article, the effect of blood pressure reduction on organ perfusion will be presented together with a review of techniques of achieving hypotension. A summary of results is included and, based on this data, recommendations are offered regarding the application and limits of deliberate hypotension.     

Interleukin-1 beta concentration of gingival crevicular fluid

The concentration of interleukin-1 beta is elevated in inflamed gingival tissue. Therefore a method for the measurement of interleukin-1 beta (Il-1 beta) in gingival crevicular fluid (GCF) using a commercially available Il-1 beta ELISA was developed. GCF was collected with periopaper strips and 4 protocols of sampling using filter paper strips were tested; the method with a recovery rate of 111.9% (SD: +/- 14.5%) was chosen for subsequent analysis of all samples. Il-1 beta concentration in GCF of periodontitis patients and a healthy control group was determined. Patients (n = 19, mean age: 29.3 years) had not been treated. The healthy control group (n = 14, mean age: 22.8 years) showed, after a hygiene regimen of 2 weeks, no clinical signs of gingival/periodontal inflammation. Probing depth, clinical attachment level, bleeding upon probing, and a modified plaque index were recorded. Il-1 beta could be detected in all GCF samples. The concentration ranged between 22.8 ng/ml and 150 ng/ml in the healthy control group and between 85.8 ng/ml and 882.2 ng/ml in the periodontitis patients. No sex-related differences were noted. According to our present results the determination of GCF Il-1 beta concentration is possible using commercially available test kits if the principle of sample preparation is adapted to the specific requirements of GCF analysis.     

Immunosuppression in therapy of glomerulonephritis

This study clinically evaluated a bioabsorbable barrier membrane designed for periodontal regeneration. Ten Class II furcations and 12 interproximal infrabony defects were treated by flap debridement and placement of a bioabsorbable barrier membrane using the principles of guided tissue regeneration. Treatment was evaluated in terms of changes in vertical probing depth, horizontal attachment level, clinical attachment level, and recession. Baseline data were collected on the day of surgery, and outcome measurements were performed at the 1-year appointment. The mean initial probing depth for Class II furcations was 6.5 mm. At 1 year, the mean probing depth was reduced to 2.9 mm, a 3.6 mm change. These differences were clinically and statistically significant (P < 0.01). There was a mean gain of 2.4 mm in clinical attachment level (P < 0.01) and a mean 3.4-mm change in horizontal attachment level (P < 0.01). Recession increased 1.2 mm. For interproximal infrabony defects, there was a mean probing depth reduction of 5.0 mm (P < 0.01), a mean gain of clinical attachment level of 3.8 mm (P < 0.02), and a mean increase of 1.2 mm in recession (P < 0.04). The results indicate that significant improvements occurred after treatment of Class II furcations and interproximal infrabony defects with the use of a bioabsorbable barrier membrane and guided tissue regeneration.     

Results of limited initial periodontal therapy in smokers and non-smokers

Eighty-seven adult patients (54 non-smokers and 33 smokers) with moderate to advanced periodontitis were treated with 1-hour full-mouth subgingival scaling and root planing, with no maintenance recalls, during this 9-month study. Clinical parameters assessed at target sites included probing depth, clinical attachment level, bleeding on probing, gingival index, and plaque index. Data were collected at baseline, and 3, 6, and 9 months. Baseline probing depth for non-smokers was 5.46 +/- .46 mm and for smokers 5.70 +/- 0.66 mm. Data analysis (t test) revealed that both non-smokers and smokers had a statistically significant decrease (P < 0.05) in probing depth at 3 months which was maintained throughout the study. At 9 months non-smokers maintained a mean decrease in probing depth of 0.60 mm and smokers a mean decrease of 0.65 mm. Both smokers and non-smokers displayed a significant gain (P < 0.05) in clinical attachment level after initial therapy when compared to baseline readings. At 9 months the mean gain in clinical attachment level for non-smokers was 0.47 mm and 0.59 mm for smokers. Plaque index scores remained consistent for smokers and non-smokers for the duration of the study. The gingival index at baseline was significantly (P < 0.05) lower in smokers (1.32 +/- 0.45) than non-smokers (1.45 +/- 0.40). By 9 months only the gingival index of non-smokers decreased significantly compared to baseline (1.26 +/- 0.37). Bleeding on probing was a prerequisite for target sites at baseline. At 9 months both smokers (0.67 +/- 0.39) and non-smokers (0.78 +/- 0.30) had a significant decrease in bleeding on probing compared to baseline. At 9 months there were no significant differences between smokers and non-smokers comparing probing depth, clinical attachment level, plaque index, bleeding on probing, and gingival index. The data have shown that smokers and non-smokers responded similarly after 9 months to the limited amount of initial therapy provided.     

Prognosis versus actual outcome. III. The effectiveness of clinical parameters in accurately predicting tooth survival

Tooth loss for 100 treated periodontal patients (2,509 teeth) under maintenance care was evaluated to determine the effectiveness of commonly taught clinical parameters utilized in the assignment of prognosis in accurately predicting tooth survival. Previous studies in this series evaluated prognosis as a surrogate variable representing the condition of the tooth at a particular point. In this study, survival analysis was used to evaluate the relationship of these common clinical parameters to an actual end point, tooth loss. Robust log rank tests indicated that initial probing depth, initial furcation involvement, initial mobility, initial crown-to-root ratio, and initial root form were all associated with tooth loss. In addition, smoking and increased initial bone loss were both found to be associated with increased risk of tooth loss while fixed abutment status was associated with a decreased risk of tooth loss. A Cox proportional hazards regression model showed that initial probing depth, initial furcation involvement, initial mobility, initial percent bone loss, presence of a parafunctional habit without a biteguard, and smoking were all associated with an increased risk of tooth loss. This model suggests that patients are twice as likely to loose their teeth if there is increasing mobility, if they have a parafunctional habit and do not wear a biteguard, or if they smoke. From these data there does appear to be a relationship between the assigned prognosis and tooth loss. Teeth with worse prognosis have a worse survival rate, but the commonly taught clinical parameters used in the traditional method of assignment of prognosis do not adequately explain that relationship. Furthermore, initial prognosis did not adequately explain the condition of the tooth or accurately predict the tooth's survival. These results seem to indicate that the effect of these clinical parameters on tooth survival is only partially reflected in the assigned prognosis initially, suggesting that perhaps some of the clinical parameters should be weighed more heavily than others when assigning prognosis. Further studies are needed to develop a more accurate method for the assignment of prognosis.     

Integrated connective tissue in bioabsorbable barrier material and periodontal regeneration

The objective of this study was to evaluate the relationship between integrated connective tissue (ICT), that is, the presence of connective tissue into the membrane structure, and the clinical outcome of membrane-supported periodontal surgery. Twenty-six systemically healthy subjects affected by chronic adult periodontitis were enrolled in the study. One tooth site per patient, associated with an angular bony defect and an attachment loss of > 7 mm, was selected to be treated by means of a guided tissue regeneration procedure using a bioabsorbable membrane. Barrier material was surgically removed after 4 weeks for SEM analysis. For each treated site, the difference in clinical attachment loss, probing depth, and gingival recession between the baseline examination and follow-up 6 months after the second surgery was calculated. Gain of attachment was statistically (P < 0.001) greater in sites with no membrane exposure when compared to sites with exposed barrier material (5.5 +/- 1.0 vs. 4.0 +/- 0.6), while further gingival recession was greater (3.0 +/- 0.9 vs. 2.1 +/- 0.5) in sites with clinically exposed membranes. The results of SEM analysis revealed that when connective tissue structures were observed on membrane surfaces, no bacteria could be detected; conversely, areas heavily colonized by bacteria did not show the presence of connective tissue. Regression analysis indicated that integrated connective tissue on the external layer of the barrier material was positively correlated with the amount of attachment gain and negatively with the amount of gingival recession. Bacterial colonization of the membrane was negatively correlated with attachment gain and positively with gingival recession. It was concluded that connective tissue integration is an important biological phenomenon in preventing membrane exposure and bacterial plaque colonization and thus in enhancing the clinical outcome following guided tissue regeneration surgery.     

Postoperative healing complications associated with Gore-Tex Periodontal Material. Part II. Effect of complications on regeneration

The gain in open probing attachment level as a result of a guided tissue regeneration procedure with Gore-Tex Periodontal Material was measured in 62 sites. The incidence of complications was evaluated. When sites with a complication were compared to those without the complication, there was no statistically different gain or loss of newly regenerated tissue. However, the occurrence of sloughing of the gingival flap decreased the amount of gain in open probing attachment level. Analysis of the data also revealed that the combined use of allografts and a delay in the removal of the Gore-Tex Periodontal Material had a synergistic positive effect on the gain in open probing attachment level. No association between these treatment variables and the incidence of the complications was found.     

Clinical response of localized recurrent periodontitis treated with scaling, root planing, and tetracycline fiber

The purpose of this study was to compare the clinical efficacy of scaling and root planing alone versus tetracycline fiber therapy used adjunctively with scaling and root planing in the treatment of nonresponsive active periodontitis in patients under supportive periodontal therapy. Thirty patients who were receiving supportive treatment and had at least two nonadjacent periodontitis sites with a probing depth of between 4 and 8 mm and bleeding on probing, or had aspartate aminotransferase (AST) levels above 800 microIU in the gingival crevicular fluid in separate quadrants participated in this study. For each patient, the test sites were treated with scaling and root planing plus tetracycline fibers while the control site was treated with scaling and root planing only. Probing depths, clinical attachment levels, gingival recession, AST levels, and bleeding on probing were recorded and subgingival plaque samples were collected at baseline and 1, 3, and 6 months following treatment. At 3 months after treatment, there was a reduction of bleeding on probing and probing depth, and a gain of clinical attachment in both test and control sites. The mean reduction in probing depth of the test sites was 1.38 mm and the attachment gain was 0.8 mm after 6 months. The clinical response obtained at 3 months following therapy was maintained throughout the 6-month follow-up period. However, there were no statistically significant differences between sites treated with scaling and root planing alone and those treated with combined tetracycline therapy. Most of the reductions of probing depths in the fiber group were attributed to gingival recession. The present study did not confirm the efficacy of adjunctive tetracycline fibers in treating nonresponsive sites in maintenance subjects with regard to probing depth reduction or clinical attachment gain. Reinfection of the pockets from untreated sites and extra-crevicular regions may explain the insignificant response to local tetracycline therapy.     

Nitric oxide, the biological mediator of the decade: fact or fiction?

Nitric oxide (NO), an atmospheric gas and free radical, is also an important biological mediator in animals and humans. Its enzymatic synthesis by constitutive (c) and inducible (i) isoforms of NO synthase (NOS) and its reactions with other biological molecules such as reactive oxygen species are well characterized. NO modulates pulmonary and systemic vascular tone through its vasodilator property. It has antithrombotic functions and mediates some consequences of the innate and acute inflammatory responses; cytokines and bacterial toxins induce widespread expression of iNOS associated with microvascular and haemodynamic changes in sepsis. Within the lungs, a diminution of NO production is implicated in pathological states associated with pulmonary hypertension, such as acute respiratory distress syndrome: inhaled NO is a selective pulmonary vasodilator and can improve ventilation-perfusion mismatch. However, it may have deleterious effects through modulating hypoxic pulmonary vasoconstriction. Inhibitors of NOS may be of benefit in inotrope-refractory septic shock, but toxicity of newly developed selective iNOS inhibitors have prevented clinical trials of efficacy. An expanding literature on the origins and measurement of NO in exhaled breath implicates NO as a potentially useful marker of disease activity in respiratory tract inflammation in the future. This report reviews some aspects of research into the clinical importance of nitric oxide.