Immunization of Macaca fascicularis against experimental periodontitis using a vaccine containing cysteine proteases purified from Porphyromonas gingivalis

INTRODUCTION

Periodontitis is a common infectious disease to which Porphyromonas gingivalis has been closely linked, in which the attachment tissues of the teeth and their alveolar bone housing are destroyed. We conducted a study to determine if immunization using a purified antigen could alter the onset and progression of the disease.

METHODS

Using the ligature-induced model of periodontitis in Macaca fascicularis, we immunized five animals with cysteine protease purified from P. gingivalis and used an additional five animals as controls. Alveolar bone loss was measured by digital subtraction radiography.

RESULTS

Immunization induced high titers of specific immunoglobuin G serum antibodies that were opsonic. Total bacterial load, levels of P. gingivalis in subgingival plaque and levels of prostaglandin E(2) in gingival crevicular fluid were significantly reduced. Onset and progression of alveolar bone loss was inhibited by approximately 50%. No manifestations of toxicity were observed.

CONCLUSIONS

Immunization using a purified protein antigen from P. gingivalis inhibits alveolar bone destruction in a ligature-induced periodontitis model in M. fascicularis.

Protective effects of Tacrolimus, a calcineurin inhibitor, in experimental periodontitis in rats

OBJECTIVE

Periodontitis is a well-appreciated example of leukocyte-mediated bone loss and inflammation with pathogenic features similar to those observed in other inflammatory diseases, such as arthritis. Since Tacrolimus, is an immunomodulatory drug used for the treatment of some cases of arthritis, we hypothesized that it may modulate periodontal disease.

DESIGN

Using a murine model of ligature-induced periodontal disease, we assessed the effects of daily administrations of Tacrolimus (1mg/kg body weight) on bone loss, enzymatic (myeloperoxidase) analysis, differential white blood cells counts, airpouch exudate and cytokine expression for 5-30 days.

RESULTS

Radiographic, enzymatic (myeloperoxidase) and histological analysis revealed that Tacrolimus reduced the severity of periodontitis. More specifically, Tacrolimus suppressed the expression of serum interleukin (IL-1beta), tumour necrosis factor (TNF-alpha), IL-6, airpouch exudate PGE(2) and leukocytosis usually observed after the induction of periodontitis. Tacrolimus treatment in periodontitis-induced rats conferred protection against the inflammation-induced tissue and bone loss associated with periodontitis, through a mechanism involving IL-1beta, TNF-alpha and IL-6.

CONCLUSIONS

The effects of Tacrolimus on periodontal disease pathogenesis may provide clues to a novel approach to host modulation therapy in destructive periodontal disease.

5-aminoisoquinolin-1(2H)-one, a water-soluble poly (ADP-ribose) polymerase (PARP) inhibitor reduces the evolution of experimental periodontitis in rats

BACKGROUND

Poly (ADP-ribose) polymerase (PARP), a nuclear enzyme activated by strand breaks in DNA, plays an important role in the tissue injury associated with ischaemia-reperfusion and inflammation. Recent studies have demonstrated that PARP activation plays a crucial role in the pathogenesis of acute periodontal injury.

AIM

We have investigated the effect of 5-aminoisoquinolin-1(2H)-one (5-AIQ), a water-soluble PARP inhibitor, in a rat model of periodontitis.

MATERIALS AND METHODS

Periodontitis was induced in rats by placing a 2/0 braided silk ligature around the lower left first molar. At day eight, the gingivomucosal tissue encircling the mandibular first molar was removed for biochemical and histological analysis.

RESULTS AND CONCLUSIONS

Ligation significantly induced an increased neutrophil infiltration and a positive staining for PARP activation. Ligation significantly increased Evans blue extravasation in gingivomucosal tissue and alveolar bone destruction. Intraperitonial injection of 5-aminoisoquinolin-1(2H)-one (5-AIQ) (5 mg/kg daily for eight days) significantly decreased all of the parameters of inflammation as described above. This suggests that inhibition of PARP may represent a novel approach for the treatment of periodontal disease.

[Prevalence and related factors of periodontitis in community-dwelling Chinese with diabetes]

OBJECTIVE

To evaluate the periodontal conditions in community-dwelling Chinese with diabetes and analyze some related factors.

METHODS

A total of 90 (45- to 84- year-old) patients with diabetes, participating in community-based non-communicable diseases management system, were recruited in this study. The examination items on these patients included periodontal measurements performed by pocket probing depth (PPD), attachment loss (AL), sulcus bleeding index (SBI), plaque index (PLI), and blood sugar metabolic level surveillance, as well as structured questionnaire interview.

RESULTS

The prevalence of periodontitis was 100%, while 37.1% was diagnosed as having mild periodontitis, 24.4% with moderate, and 38.5% with advanced periodontitis. The AL level in male was significantly higher than that in female. The periodontal destruction was highly correlated with HbA1C value and affected by some socio-behavior factors based on multinomial logistic model.

CONCLUSIONS

There is a positive correlation between AL and HbA1C level, and AL and HbA1C should be measured regularly. The patients' periodontal inflammation needs effective control. Priority should be given to the low income population and those with little periodontal knowledge for behavior interventions.

[Application of xidiphone in complex of measures for inflammatory periodontal disease prevention]

Investigation of basic biochemical parameters of mixed saliva during sugar and urea tests including application of xidiphone has been carried out. Following parameters--pH, concentration of calcium, inorganic phosphate and fluoride--were measured. It was shown that xidiphone was an universal regulator of acid-base state, calcium-phosphorus an calcium-fluoride homeostasis in oral cavity.

A comparison of the efficacy and ease of use of dental floss and interproximal brushes in a randomised split mouth trial incorporating an assessment of subgingival plaque

PURPOSE

Previous studies have compared the use of interdental brushes and dental floss. However, none have attempted to compare their effects on subgingival plaque. Nor have smokers been excluded from previous studies, where they may have affected the assessment of gingival inflammation.

MATERIALS AND METHODS

The present study compared, in untreated patients suffering from mild to moderate periodontitis, the efficacy of dental floss (DF) and interdental brushes (IDB) in the reduction of plaque, gingival inflammation and probing depth in a one-month period prior to subgingival debridement. Ten patients used DF for one side of the dentition and IDB for the other side for one month. Oral hygiene instruction was given at baseline. Measurements were made at baseline and at one month.

RESULTS

With IDB, the mean approximal plaque score reduced supragingivally from 14.5 to 5.7 at one month, and with DF, from 12.9 to 5.3; subgingivally the score reduced from 17.3 to 6.7, and 16.7 to 8.1 respectively (p < 0.001). BOP and mean probing depth reduced over time for IDB sites, but not DF sites (p < 0.01). Overall there were no differences between the two devices. Patients preferred IDB because of its simpler method of use.

CONCLUSIONS

The use of IDB and DF resulted in similar beneficial effects on subgingival plaque and proximal gingival health.

Microbiological composition associated with interleukin-1 gene polymorphism in subjects undergoing supportive periodontal therapy

BACKGROUND

Interleukin-1 gene polymorphism (IL-1 gene) has been associated with periodontitis. The present study examined the subgingival microbiota by IL-1 gene status in subjects undergoing supportive periodontal therapy (SPT).

METHODS

A total of 151 subjects with known IL-1 gene status (IL-1A +4845/IL-1B -3954) (IL-1 gene) were included in this study. Clinical data and subgingival plaque samples (40 taxa) were collected. These taxa were determined by the checkerboard DNA-DNA hybridization method.

RESULTS

Gender, smoking habits (n-par tests), age, and clinical periodontal conditions did not differ by IL-1 gene status. IL-1 gene-negative subjects had a higher total bacterial load (mean difference, 480.4 x 10(5); 95% confidence interval [CI], 77 to 884 x 10(5); P <0.02). The levels of Actinobacillus actinomycetemcomitans (mean difference, 30.7 x 10(5); 95% CI, 2.2 to 59.5 x 10(5); P <0.05), Eubacterium nodatum (mean difference, 4.2 x 10(5); 95% CI, 0.6 to 7.8 x 10(5); P <0.02), Porphyromonas gingivalis (mean difference, 17.9 x 10(5); 95% CI, 1.2 to 34.5 x 10(5); P <0.05), and Streptococcus anginosus (mean difference, 4.0 x 10(5); 95% CI, 0.2 to 7.2 x 10(5); P <0.05) were higher in IL-1 gene-negative subjects, an observation specifically found at sites with probing depths <5.0 mm.

CONCLUSIONS

Bleeding on probing did not differ by IL gene status, reflecting clinical SPT efficacy. IL-1 gene-negative subjects had higher levels of periodontal pathogens. This may suggest that among subjects undergoing SPT, a lower bacterial load is required in IL-1 gene-positive subjects to develop the same level of periodontitis as in IL-1 gene-negative subjects.

Tooth loss in well-maintained patients with chronic periodontitis during long-term supportive therapy in Brazil

AIM

The objective of this retrospective study was to assess the reasons for tooth loss in a sample of patients who underwent periodontal therapy and supportive periodontal therapy (SPT) in a Brazilian private periodontal practice.

MATERIAL AND METHODS

A sample of 120 subjects who had been treated and maintained for 10 years or longer was selected from patients attending a periodontal practice. All patients followed a similar treatment: basic procedures, re-evaluation and periodontal surgery where indicated. Reasons for tooth loss were categorized as periodontal, caries, endodontal, root fractures and extraction of retained or partially erupted third molars.

RESULTS

Of the 2927 teeth present at the completion of active periodontal treatment, 53 (1.8%) were lost due to periodontal disease, 16 (0.5%) for root fracture, six (0.2%) to caries, five (0.2%) for endodontic reasons and 31 (1.0%) were lost to extraction of retained or partially erupted third molars. Logistic regression analysis was performed to investigate the association between five independent variables with tooth loss due to periodontitis. Only age (> 60 years) and smoking were statistically significant (p < 0.05).

CONCLUSION

The findings of this survey were consistent with previous studies. Older subjects and smokers were more susceptible to periodontal tooth loss. In addition, patients with generalized chronic periodontitis were treated and maintained for long-term periods with low rates of tooth loss.

Abszess in der Impulsgeneratortasche nach apikaler Parodontitis

Deep brain stimulation of the subthalamic nucleus is an important treatment option for advanced stages of idiopathic Parkinson's disease, leading to significant improvement of motor symptoms in suited patients. Hardware-related complications such as technical malfunction, skin erosion, and infections however cause patient discomfort and additional expense. The patient presented here suffered a putrid infection of the impulse generator site following only local dental treatment of apical parodontitis. Therefore, prophylactic systemic antibiotic treatment is recommended for patients with implanted deep brain stimulation devices in case of operations, dental procedures, or infectious disease.

Effect of mechanical and antiseptic therapy on peri-implant mucositis: an experimental study in monkeys

OBJECTIVES

This experiment was performed to evaluate clinically and histologically the effect of mechanical therapy with or without antiseptic therapy on peri-implant mucositis lesions in nine cynomolgus monkeys.

MATERIAL AND METHODS

Two ITI titanium implants were inserted into each side of the mandibles. After 90 days of plaque control and soft tissue healing, a baseline clinical examination was completed. Peri-implant lesions were induced by placing silk ligatures and allowing plaque to accumulate for 6 weeks. The clinical examination was then repeated, and the monkeys were randomly assigned to three treatment groups: group A, mechanical cleansing only; group B, mechanical cleansing and local irrigation with 0.12% chlorhexidine (CHX) and application of 0.2% CHX gel; and group C, control, no treatment. The implants in treatment groups A and B were treated and maintained according to the assigned treatment for two additional months. At the end of the maintenance period, a final clinical examination was performed and the animals were sacrificed for biopsies.

RESULTS

The mean probing depths (PD) values at mucositis were: 3.5, 3.7, and 3.4 mm, and clinical attachment level (CAL) = 3.8, 4.1, and 3.9 mm for treatment groups A, B and C, respectively. The corresponding values after treatment were: PD = 1.7, 2.1, and 2.5 mm, and CAL=2.6, 2.6, and 3.1 mm. ANOVA of mean changes (Delta) in PD and CAL after treatment showed no statistical difference between the treatment groups. Comparison of the mean changes in PD and CAL after treatment yielded statistical differences between the control and treatment groups P < 0.01. According to the t-test, no statistical difference was found between treatment groups A and B for the PD reduction but there was a significant difference for the CAL change, P < 0.03. Group A had significantly more recession and less CAL gain than group B. Non-parametric tests yielded no significant differences in modified plaque index (mPlI) and gingival index (GI) after treatment between both treatment groups. Frequencies and percent distributions of the mPlI and GI scores changed considerably for both treatment groups when compared with the changes in the control group after treatment. With regard to the histological evaluation, no statistical differences existed between the treatments for any linear measurement. The proportion of inflammation found in the mucosal tissues of the control implants was greater than the one found for both treatment groups, P < 0.01. More importantly, both treatment groups showed a similar low proportion of inflammation after 2 months of treatment.

CONCLUSIONS

Within the limitations of this experiment, and considering the supportive plaque control rendered, it can be concluded that for pockets of 3-4 mm: (1) mechanical therapy alone or combined with CHX results in the clinical resolution of peri-implant mucositis lesions, (2) histologically, both treatments result in minimal inflammation compatible with health, and (3) the mechanical effect alone is sufficient to achieve clinical and histologic resolution of mucositis lesions.

Risk ofPorphyromonas gingivalisRecolonization During the Early Period of Periodontal Maintenance in Initially Severe Periodontitis Sites

BACKGROUND

Porphyromonas gingivalis is considered a critical pathogen of periodontal diseases including recurrent periodontitis. The profound effects of active periodontal treatment (APT) on P. gingivalis elimination were previously demonstrated and revealed that the subsequent P. gingivalis-free or -suppressed status seems to be maintained during early periodontal maintenance (PMT). The aim of the present study was to show the occurrence of microbial recolonization during this early PMT period.

METHODS

In total, 128 sites from 11 generalized chronic periodontitis patients and one generalized aggressive periodontitis patient underwent clinical and microbiologic examination at baseline (Exam-I), after APT (Exam-II), and in PMT (Exam-III). Exam-III was carried out an average of 4.5 +/- 3.5 months after Exam-II. Detection and quantification of putative pathogens were performed using a polymerase chain reaction-based method.

RESULTS

The PMT used was effective in maintaining the clinical conditions improved by APT. However, in microbiological examinations, Exam-III showed higher detection frequency and levels of P. gingivalis than Exam-II. This suggests that a P. gingivalis recolonization started in the early PMT period. P. gingivalis-increased sites then showed significantly more severe signs of periodontitis in Exam-I than P. gingivalis-stable sites (bleeding on probing frequency: 76.7% versus 56.5%; suppuration frequency: 41.9% versus 12.9%). On the other hand, in Exam-II, no significant differences of clinical parameters were noted between P. gingivalis-increased and -stable sites.

CONCLUSION

Severe periodontitis sites before APT seemed to place them at risk of P. gingivalis recolonization in the early PMT period, and this microbial restoration could be a cause of recurrent periodontitis.

The outcome of a preventive dental care programme on the prevalence of localized aggressive periodontitis in Down's syndrome individuals

BACKGROUND

Periodontal disease in Down's syndrome (DS) individuals develops earlier and is more rapid and extensive than in age-matched normal individuals. The present study evaluated a group of DS patients, who had been participating in a 10-year preventive dental programme, for the impact of the programme on their periodontal status.

METHODS

Thirty DS patients (mean age 23.3 +/- 4 years) were compared with 28 age-matched healthy controls (mean age 22.8 +/- 5 years). The hygiene level, gingival condition and periodontal status (periodontal probing depth, clinical attachment level and radiographic alveolar bone loss) were determined.

RESULTS

In spite of similar oral hygiene and gingival measures, DS patients, as opposed to the control ones, had a severe periodontal disease. The prevalence, extent and severity of periodontitis in the DS group were significantly greater than in the control group. The teeth most commonly and severely affected were the lower central incisors and the upper first molars. DS patients lost significantly more teeth due to periodontitis.

CONCLUSIONS

The clinical and radiographic picture found in the present DS group is characteristic of localized aggressive periodontitis. Within the limitations of this study, it seems that the preventive dental programme had no effect on periodontal destruction progression of localized aggressive periodontitis in DS individuals and that impaired oral hygiene plays a relatively minor role in the pathogenesis of this disease. Future controlled studies are needed to assess the effectiveness of different preventive dental programmes in preventing the progression of periodontitis in DS patients.

Whole-grain and fiber intakes and periodontitis risk in men

BACKGROUND

Diabetes and hyperglycemia increase periodontitis risk, severity, and extent. Increased whole-grain and fiber intakes are associated with improved insulin sensitivity and may therefore affect periodontitis risk.

OBJECTIVE

The objective was to examine the associations between whole-grain and fiber intakes and periodontitis risk.

DESIGN

We prospectively followed 34,160 male US health professionals aged 40-75 y at the outset. We updated medical and lifestyle information biennially with questionnaires and diet every 4 y by using a validated food-frequency questionnaire. We excluded men reporting periodontitis, myocardial infarction, stroke, and hypercholesterolemia before 1986 and those with incomplete dietary data. All diabetics were excluded. Periodontitis was determined by a report of professionally diagnosed disease and validated by a diagnosis of periodontitis by a periodontist from a blinded review of radiographs.

RESULTS

Men in the highest quintile of whole-grain intake were 23% less likely to get periodontitis than were those in the lowest quintile (multivariate RR: 0.77; 95% CI: 0.66, 0.89; P for trend < 0.001) after adjustment for age, smoking, body mass index, alcohol intake, physical activity, and total energy intake. Periodontitis was not associated with refined-grain intake (multivariate RR comparing extreme quintiles of intake: 1.04; 95% CI: 0.89, 1.23; P for trend = 0.37). Cereal fiber was inversely related to periodontitis risk (multivariate RR comparing extreme quintiles of intake: 0.85; 95% CI: 0.73, 0.99; P for trend = 0.03), but the association was not significant after adjustment for whole-grain intake.

CONCLUSION

Increasing whole grain in the diet without increasing total energy intake may reduce periodontitis risk.

Topical H2 antagonist prevents periodontitis in a rabbit model

Cimetidine is a powerful H2 receptor antagonist that eliminates histamine's effects on chemotaxis, phagocytosis, and superoxide anion production by phagocytes. The purpose of this study was to analyze the clinical and histopathological changes associated with experimental periodontitis in rabbits in response to topically applied cimetidine. Experimental periodontitis was induced in 21 New Zealand White rabbits using Porphyromonas gingivalis (10(9) CFU) topically applied three times a week for a 6-week period to previously ligatured teeth. Topical application of cimetidine in a liposome carrier for the prevention of periodontitis was evaluated in four groups of four animals each: 1, 10, and 100 mg/ml and no treatment (positive control). In addition, there was a vehicle group (n = 3) that received liposome preparation (carrier) only, and two animals with ligature application alone served as negative controls. Periodontal disease was quantified by direct visualization and radiographical evaluation of bone loss on defleshed skulls and by histological analyses of sections stained with hematoxylin-eosin and tartrate-resistant acid phosphatase. In the no-treatment (positive control) and liposome (vehicle) groups, direct visualization and radiological measurements revealed statistically significant bone loss compared to the negative control. Application of cimetidine at all concentrations tested inhibited inflammation and bone loss by >90%. Histological findings revealed that ligated sites of the positive control and vehicle groups showed significant reduction in bone level (P < 0.05) compared to the three cimetidine groups, with a marked decrease in inflammation. The findings of this study provide morphological and histological evidence that topically active cimetidine is a potent inhibitor of P. gingivalis-elicited periodontal inflammation, arresting and/or preventing tissue destruction and influencing cell populations present in the inflammatory cell infiltrate.

Compliance as a prognostic indicator: retrospective study of 505 patients treated and maintained for 15 years

BACKGROUND

The relationship of patient compliance to overall tooth prognosis remains controversial. There are little data, often conflicting, that pertain to tooth loss as a function of patient compliance.

METHODS

This retrospective study evaluates the impact of compliance (complete versus erratic) on common periodontal clinical variables, such as probing depth, bleeding index, plaque index, and tooth loss for 505 patients in a long-term period of observation (15 to 23 years) and maintenance therapy (at least 10 years). Compliance was defined in two ways for all analyses. Under the definition for compliance 1, patients who missed <30% of all prescribed maintenance visits were classified as complete compliers. Under the definition for compliance 2, patients who never went 2 years without a maintenance visit were classified as complete compliers. Change in clinical variables was dichotomized into reduction in plaque index versus no reduction, reduction in bleeding on probing versus no reduction, reduction in the percentage of periodontal pockets>3 mm versus no reduction, no increase in decayed, missing, or filled teeth (DMFT) versus increase, and no tooth loss versus tooth loss. The effects of both definitions of compliance were then evaluated in a series of multiple logistic regression models with adjustment for potential confounders.

RESULTS

The analysis of the dichotomous change in clinical parameters over time revealed that complete compliers tended to show reduction in bleeding on probing and reduction in plaque index compared to erratic compliers for both definitions of compliance. In contrast, complete compliers under compliance 2 were less likely to have a reduction in the percentage of periodontal pockets >3 mm compared to erratic compliers, whereas complete compliers under compliance 1 had about the same likelihood of demonstrating a reduction in periodontal pockets compared to erratic compliers under this classification scheme. Under both definitions for compliance, complete compliers were more likely to exhibit tooth loss than erratic compliers, with the greatest tooth loss exhibited by complete compliers under the definition for compliance 1.

CONCLUSIONS

Based on these results, complete compliers under both definitions tended to show a reduction in plaque and bleeding on probing over time. However, change in periodontal pockets and DMFT over time varied according to the definition of compliance that was used. In addition, the results seem to indicate that the decision for tooth extraction made by dental health professionals at maintenance visits may result in greater tooth loss.

[Clinical evaluation of periodontium in pregnant women with risk of preterm birth]

OBJECTIVES

The aim of the study was to evaluate condition of the periodontium in pregnant women with pathological progress of the pregnancy, clinically and to compare it to periodontium in pregnant women in good health.

DESIGN

Over the last years, the studies have described that periodontitis caused by dental plaque, could be the risk factor for preterm birth and low birth weight.

MATERIALS AND METHODS

This study was performed in 80 pregnant women, 40 with pathologic pregnancy and 40 with normal pregnancy in it. Periodontal Indexes were used to evaluate periodontium.

RESULTS

In the searching group gingivitis gravidarum haemorrhagica diffusa and hyperplastica generalisata were dominating. In the control group gingivitis gravidatum simplex and hyperplastica localisata were observed.

CONCLUSIONS

More severe manifestation of gingivitis gravidarum was noticed in pregnant women with risk of preterm low birth. We did not prove correlation between amount of bacterial dental plaque in pregnant women and risk of preterm low birth weight.

Comparison of two automated periodontal probes and two probes with a conventional readout in periodontal maintenance patients

AIM

The aim of the present study was to test in periodontal maintenance patients whether the systems for pressure control that have been commercially developed contribute to more reproducible probing depth measurements as compared with a manual probe.

MATERIAL AND METHODS

In 12 patients duplicate measurements were made at day 0 and 1 week later. In each patient four teeth with the deepest pockets were measured at six sites. In total 288 sites were available for comparisons. The Florida Probe (FP) (159 N/cm(2)), the Jonker Probe (JP) (153 N/cm(2)), the Brodontic probe (BP) (255 N/cm(2)) and the manual probe (MP) were used in a randomized scheme.

RESULTS

Mean probing measurements showed for the FP and the JP lower recordings than for the BP and manual probe. The FP, the BP and the MP showed no differences between the duplicate measurements, except for the JP where the second measurement was deeper. Correlation coefficients between measurements at day 0 and 1 week show for the BP and the MP are 0.90 and 0.89, respectively, while for the FP and the JP they are 0.76 and 0.75, respectively.

CONCLUSION

The BP and the MP appear to be reliable tools for reproducible pocket depth measurements in periodontal maintenance patients.

Tooth loss in treated periodontitis patients responsible for their supportive care arrangements

AIM

To identify risk indicators associated with tooth loss and periodontitis in treated patients responsible for arranging supportive periodontal care (SPC).

MATERIALS AND METHODS

Ninety-seven Chinese subjects (34-77 years) who showed favourable responses to periodontal therapy provided in a teaching hospital 5-12 years previously were recalled. They were advised to seek regular SPC on discharge. Background information, general health status, smoking, oral hygiene habits, follow-up dental care, tooth loss, and periodontal parameters were investigated. Multiple regression analysis was performed.

RESULTS

Two hundred and fifty-six teeth had been lost, 195 because of self-reported periodontal reasons. Up to 26.8% sites were with pockets > or =6 mm. Positive correlations were found between total/periodontal tooth loss and (i) smoking pack-years, (ii) time spent on oral hygiene, (iii) years since therapy's conclusion, (iv) age, and negative correlations with (v) inter-dental brush use, and (vi) education levels. Tooth loss by arch was correlated with wearing of removable partial denture in that arch. Percentage sites with pockets > or =6 mm were significantly negatively correlated with percentage sites without bleeding on probing.

CONCLUSIONS

Smokers, more elderly patients, removable partial denture wearers, and patients with lower education levels or not using inter-dental brushes ought to be targeted for clinic-based SPC.

Cloricromene, a coumarine derivative, reduced the development of periodontitis in rats

Recent studies have demonstrated that cloricromene, a coumarin derivative, exerts protective effects in models of inflammation and shock. Tumour necrosis factor plays a pivotal role in the induction of genes involved in physiological processes, as well as in the response to inflammation. We investigated the effect of cloricromene in a rat model of periodontitis. Periodontitis was induced in rats by placing a 2/0 braided silk ligature around the lower left first molar. At day 8 the gingivomucosal tissue encircling the mandibular first molar was removed for evaluation of tumour necrosis factor production, neutrophil infiltration, tissue permeability, nitrotyrosine formation, poly (ADP-ribose) polymerase activation, radiography and histology. Ligation significantly induced an increased tumour necrosis factor production, neutrophil infiltration and a positive staining for nitrotyrosine formation and poly (ADP-ribose) polymerase activation. Ligation significantly increased Evans blue extravasation in gingivomucosal tissue and alveolar bone erosion as evaluated by radiography analysis. Intraperitonal injection of cloricromene (10 mg/kg daily for 8 days) significantly decreased all of the parameters of inflammation as described above. This suggests that cloricromene treatment, which reduced tumour necrosis factor production, may be of benefit in the treatment of periodontitis.

An interdisciplinary approach for improved functional and esthetic results in a periodontally compromised adult patient

In contemporary dental care, an increasing number of adult patients are seeking orthodontic treatment. In such adult patients, a combined orthodontic and other specialized therapy often offers the best option for achieving a predictable outcome to solve complex clinical problems. This case report demonstrates a combined therapy with orthodontic, periodontic, and implant-prosthodontic treatments in a 56-year six-month-old female patient with mild diastemata in the maxillary anterior region and a missing left maxillary second premolar caused by a periodontal disease with medium bone loss. The patient had improved her oral hygiene condition through periodontal treatment before orthodontic treatment. The patient was orthodontically treated with a maxillary lingual arch and a maxillary edgewise orthodontic appliance. Active orthodontic treatment was completed in 18 months, and an implant-supported prosthesis was placed with a single crown in the region of the left maxillary second premolar. The treatment outcomes, including the periodontal condition and the dental implant treatment, were stable at two years after the active orthodontic treatment. We demonstrate that combined orthodontic-periodontic-implant-prosthodontic treatment can achieve an improved masticatory function, esthetics, occlusion, and periodontal condition.

Periodontitis and pregnancy

There is an increasing amount of evidence suggesting a systemic link between periodontal disease in the pregnant mother and pre-term low birth weight (PLBW). Severe periodontitis affects at least 10% of the general population. The aetiology of periodontitis is essentially a bacterially induced inflammatory reaction within the attachment surrounding the teeth. Maternal infection has been linked with pre-term delivery. Normal pregnancy itself is associated with inflammatory changes very similar to those found in sepsis. Because the infected periodontal tissues can act as a reservoir for both bacterial products and inflammatory cytokines, it may be possible that periodontal infection and the resultant inflammation could be linked with PLBW. Current understanding suggests that prostaglandins and proinflammatory cytokines play a pivotal role in the initiation process because of the close relationship of inflammation and infection. High levels of maternally or fetally derived cytokines such as tumour necrosis factor alpha (TNFalpha) may enhance amniochorionic and decidual interleukin six (IL-6) expression. Prostaglandin E2 (PGE2) has also been associated with periodontitis and PLBW. Periodontitis is a possible risk factor for PLBW with an odds ratio of 2.30. For the majority of individuals affected with periodontitis, the condition is symptom-free until the disease is more advanced. Therefore there is the need for medical carers of pregnant patients to increase the awareness among pregnant women themselves. Although there is plenty of evidence associating periodontitis with PLBW, interventional studies for the treatment of periodontitis measuring the impact on PLBW are few in number. Therefore more good quality clinical trials are required to address this issue.

Risk avoidance: Graphs versus numbers

There have long been speculations that graphical and numerical presentations of risk statistics differ in their impact on people's wilingness to pursue actions that could harm or even kill them. But research has been unclear about the processes whereby the pictorial character of graphical displays per se might affect those risky decisions or even whether such effects actually occur. In two studies, we demonstrate that the pictorial nature of a graphical risk display can, indeed, increase risk avoidance. This increase is associated with a heightened impression of the riskiness of less safe alternatives. The results suggest that this picture-driven, intensified sense of riskiness, in turn, rests on two kinds of mechanisms: one cognitive, the other affective. Cognitively, pictorial presentations impose weaker upper bounds on people's internal representations of the chances that riskier alternatives will bring about actual harm. Affectively, pictures ignite stronger, more aversive negative associations with riskier options and their outcomes.

Effect of sodium alendronate on alveolar bone resorption in experimental periodontitis in rats

BACKGROUND

Bisphosphonates are potent inhibitors of bone resorption and were shown to inhibit bone resorption in experimental periodontitis by unknown mechanisms. We studied the effect of the aminobisphosphonate sodium alendronate (SA) in experimental periodontitis. Wistar rats were subjected to ligature placement around the second upper left molars.

METHODS

Animals were treated with SA 0.01 to 0.25 mg/kg subcutaneously (sc), either 1 hour before (prophylactic) or starting 5 days after (therapeutic) periodontitis induction and daily until the rats were sacrificed (11 days). Controls received saline. Animals were weighed daily. Alveolar bone loss was measured as the difference (in millimeters) between the cusp tip and the alveolar bone. The periodontium and the surrounding gingivae were examined at histopathology, and the neutrophil influx into the gingivae was assayed using myeloperoxidase activity. The local bacterial flora was assessed through culture of the gingival tissue in standard aerobic and anaerobic media.

RESULTS

Alveolar bone loss was significantly and dose dependently inhibited by SA either as a prophylactic or therapeutic treatment compared to the control. SA reduced tissue lesion at histopathology, with partial preservation of the periodontium, coupled to decreased myeloperoxidase activity compared to the control. The reduced neutrophil influx was also shown in carrageenan-induced peritonitis, used as a control experiment for this parameter. SA also significantly inhibited the growth of pigmented bacilli and Fusobacterium nucleatum, which are important in the pathogenesis of periodontal disease. SA also inhibited the in vitro growth of isolated Peptostreptococcus sp.

CONCLUSION

Sodium alendronate preserves alveolar bone resorption and has anti-inflammatory and antibacterial activities in experimental periodontitis.

Supportive periodontal therapy using mechanical instrumentation or 2% minocycline gel: a 12 month randomized, controlled, single masked pilot study

OBJECTIVE

To compare the short-term performance of subgingival local delivery of 2% minocycline gel and conventional subgingival debridement in supportive periodontal therapy (SPT) patients.

METHODS

Forty adult patients having completed active treatment for moderate to advanced chronic periodontitis were included in a randomized, controlled, single masked maintenance care pilot study. Sites with residual pocket probing depths > or =5 mm and bleeding on probing were treated with either minocycline gel (minocycline-group) or scaling and root planing only (debridement-group) at baseline, 3, 6, and 9 months. Clinical and microbiological examinations were performed at baseline, 3, 6, 9, and 12 months.

RESULTS

Full-mouth plaque and bleeding scores remained <10% and <20%, respectively, for both groups throughout the study. In both groups there was a persistent reduction in number of teeth and sites with probing pocket depths > or =5 mm (p<0.05) with no significant differences between the groups. The prevalence of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Prevotella nigrescens, remained at levels < or =10(5) in the majority of patients and sites in both groups.

CONCLUSION

This pilot study failed to show a difference between local delivery of 2% minocycline gel as mono-therapy and traditional subgingival debridement in patients on SPT.

Neonatal dexamethasone and chronic tianeptine treatment inhibit ligature-induced periodontitis in adult rats

OBJECTIVE

The responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis has been found to play a significant role for susceptibility and resistance to periodontal disease. In the present study we have investigated the effects of two different treatment strategies, which have been found to down-regulate the HPA axis, on ligature-induced periodontitis.

METHODS

In experiment 1, newborn rats were treated with the synthetic glucocorticoid hormone dexamethasone-21-phosphate, which permanently down-regulates HPA axis responsiveness. In experiment 2, adult rats were treated with the novel antidepressant drug tianeptine, which opposes the action of stress. Periodontitis was inflicted upon all rats. Just before decapitation the animals received gram-negative bacterial lipopolysaccharide (LPS) to induce a robust immune and HPA axis response.

RESULTS

Compared to the saline-treated control rats, dexamethasone-treated rats had significantly less periodontal bone loss (p < 0.01), reduced expression of glucocorticoid receptors in the hippocampus (p < 0.001), lower corticosterone (p=0.01) and higher plasma levels of the cytokine tumor necrosis factor (TNF)-alpha (p < 0.05) after LPS challenge. Also the tianeptine-treated rats showed significantly reduced periodontal bone loss (p=0.01), enhanced plasma levels of TNF-alpha (p < 0.05), and transforming growth factor-1beta (p < 0.01), whereas no significant difference was found in corticosterone levels.

CONCLUSION

An individual's responsiveness to danger signals, whether they are of immunological, chemical, or psychological origin, may be an important factor for explaining variability in susceptibility to periodontal disease. The results may provide new insight into the mechanisms of periodontal disease development, and open new vistas for disease prevention.

Intraoral delivery of antimicrobials

Antimicrobial therapies for oral diseases have been in use for centuries, but have undergone rapid changes in the last decade. In the coming years, antimicrobial strategies will become more sophisticated and efficacy will be greatly improved as new therapeutic technologies emerge. New delivery systems for common antimicrobials and novel agents to modulate the immune system, as well as biofilm formation and maturation, may be on the horizon. This review describes the development and the application of intraoral antimicrobial drug delivery in the oral environment. Current clinical uses of antimicrobials as well as future approaches to the treatment and prevention of oral infectious diseases are discussed.

[Development of recommendations for the use of preventive and therapeutic modalities in cases of inflammatory diseases of parodontium based on mathematical modeling]

An approach to development of recommendations for the use of preventive and curative modalities in cases of inflammatory diseases of the parodontium is studied basing on mathematical modeling. It is suggested to use the mathematical apparatus of Markov's processes. The effectiveness of the suggested approach was demonstrated on the example of prognostication of the parodontium status in the staff of one of the plants of Saint-Petersburg.

Increased physical activity reduces prevalence of periodontitis

OBJECTIVES

Physical activity has been shown to have a protective relationship with several chronic diseases. Recently, physical activity was also found to reduce the risk of periodontitis in a study in male health professionals. However, the relationship between physical activity and periodontitis in a diverse group of individuals is not thoroughly examined. The purpose of this study was to examine if there is an association between sustained physical activity and periodontitis in a subset of the third national health and nutrition examination survey (NHANES III).

METHODS

NHANES III participants 18 years of age or older who had had a periodontal examination and reported to have a similar physical activity (or inactivity) level for 10 years or longer were selected (n=2521). Multivariable logistic regression analysis was used to estimate the association between physical activity and periodontitis. The analysis was adjusted for: age, gender, race, education, smoking, body mass index, poverty index, vitamin use, healthy eating index, time since last dental visit, gingival bleeding, and dental calculus.

RESULTS

Engaging in the recommended level of physical activity was significantly associated with lower periodontitis prevalence (OR=0.58, 95% CI, 0.35-0.96). Smoking, however, was found to modify this relationship. The association was strong and significant among never (OR=0.46, 95% CI, 0.23-0.93) and former smokers (OR=0.26, 95% CI: 0.09-0.72), but not among current smokers (OR=1.10, 95% CI: 0.48-2.53).

CONCLUSIONS

These results suggest that engaging in the recommended level of exercise is associated with lower periodontitis prevalence, especially among never and former smokers.

[Pain during and after root canal treatment]

Toothache can be prevented or remedied with a root canal treatment. Unfortunately a root canal treatment can also be the cause of pain. During a root canal treatment pain can be suppressed by local anesthesia, the use of the airotor, the attitude of the dentist and his communication with the patient. Afterpain has three causes: damage and iatrogenic apical periodontitis, pulpitis and continuing apical periodontitis. In this article the possible treatment of pain by a root canal treatment are extensively discussed.

Exposure of implants using a modified multiple-flap transposition vestibuloplasty

AIM

To introduce a minimally invasive operation to improve the condition of the soft tissues around the implants in an atrophied mandible, at the same time, as uncovering the implants.

PATIENTS AND METHOD

A multiple-flap transposition vestibuloplasty was done in 11 patients after the insertion of four implants in the interforaminal region of an atrophied mandible. Improvement in soft tissues and successful exposure of implants and attached gingiva were evaluated during a follow-up period of 55 months. All the patients were operated on local anaesthesia as outpatients.

RESULTS

Adequate exposure of implants and an area of attached gingiva 4-9 mm wide were attained. There was no bleeding on probing or local infection.

CONCLUSION

The transposition multiple-flap vestibuloplasty is a simple and minimally invasive method of improving the condition of soft tissue after insertion of implants. It does not limit the patients' routine activities and avoids staged operations.

Systemic Low-Dose Doxycycline and Alendronate Administration and Serum Interleukin-1Beta, Osteocalcin, and C-Reactive Protein Levels in Rats

BACKGROUND

The aim of the present study was to evaluate the effects of systemic administration of low-dose doxycycline and a bisphosphonate, alendronate, on serum levels of interleukin-1beta (IL-1beta), osteocalcin (OC), and C-reactive protein (CRP) in experimental periodontitis in rats.

METHODS

Experimental periodontitis was induced by repeated injection of purified lipopolysaccharide (LPS) derived from Escherichia coli endotoxin. Forty-seven adult male Sprague-Dawley rats were divided into five study groups and given LPS, LPS + doxycycline, LPS + alendronate, LPS + doxycycline + alendronate, and saline control. At the end of the 1-week protocol, blood samples were obtained, and the rats were sacrificed. Serum samples were analyzed for IL-1beta, OC, and CRP concentrations by enzyme-linked immunosorbent assay (ELISA). The jaws were defleshed, and alveolar bone loss was assessed morphometrically. Data were evaluated statistically by non-parametric tests.

RESULTS

Morphometric measurements revealed significantly more bone loss in the LPS group compared to the saline control group (P <0.05). Alendronate revealed slight inhibition on alveolar bone loss either alone or in combination with doxycycline (alveolar bone loss: 0.41 mm in alendronate and combined drug treatment groups versus 0.45 mm in LPS and doxycycline groups). Significantly higher IL-1beta levels were observed with alendronate either alone or in combination with doxycycline than in the LPS group (P <0.05). Combined administration of doxycycline and alendronate showed significantly higher levels of OC than all of the other groups (P <0.01). Serum CRP levels did not exhibit significant differences between the study groups.

CONCLUSIONS

Alendronate either alone or in combination with doxycycline provided slight inhibition on LPS-induced alveolar bone resorption. The significantly increased serum OC level observed in the combined drug treatment group suggests that combined administration of alendronate and doxycycline might increase bone remodeling and thereby inhibit the progression of alveolar bone resorption in rats.

Impact of periodontal preventive programmes on the data from epidemiologic studies

This report provides only circumstantial evidence for the impact of programmes on periodontal epidemiology. The prerequisites for programmes and campaigns are described, and epidemiologic data on periodontal disease are compared with known changes in factors that may be affected by such activities. Unfortunately, parameters for periodontal disease as a process are not available. Only variables indicating irreversible effects on the periodontal status can be obtained. A lack of appropriate studies creates additional problems. This review indicates that preventive programmes and campaigns to improve oral hygiene have affected periodontal epidemiologic data concerning gingivitis and mild/moderate periodontitis favourably. Severe periodontitis seems not to have been influenced by such activities. Smoking is strongly associated with the severity of periodontitis. Therefore, a positive effect may be anticipated following the smoking cessation campaigns currently introduced worldwide. However, because of the irreversible nature of our epidemiologic parameters, it will take decades before any effect may be evident. It is recommended that periodontal epidemiology should be revitalized by introducing a nominalistic categorization instead of the changing essentialistic approaches used so far in order to facilitate the interpretation of data.

[Assessment of periodontal state in patients with chronic obstructive pulmonary disease--part II]

The aim of the study was to estimate the periodontal state in chronic obstructive pulmonary disease (COPD).

MATERIAL AND METHODS

The study comprised 100 patients with COPD (68 men and 32 women), aged 30-83 years (mean 63.1 +/- 10.17 years). All patients were in the II grade COPD (moderate COPD). FEV1/FVC<70% and FEV1 was within 79% and 50% of the predicted value. Beta2-adrenomimetic inhalants or in nebulization, theophylline were applied in the therapy. The control group consisted of 101 subjects (38 men and 63 women), aged 42-88 years (mean 65.3-10.36 years), with no respiratory tract diseases. The rate of smoking was similar in both groups. To examine periodontal state, periodontal pocket depth was measured (with periodontal sound), Periodontal Index (PI) and dental plaque index were assessed.

RESULTS

The frequency and severity of periodontal diseases in COPD patients were demonstrated to be significantly increased as compared to the control group (p<0.05). Adult chronic periodontitis (ACP) was observed significantly more frequently in COPD patients (84.21%) than in the control group (59.74%, p<0.05). A positive correlation was found between periodontal pocket depth and dental plaque index in patients with COPD.

CONCLUSION

The frequency and intensification of periodontal diseases speak for their cause-and-effect relationship with COPD. The prophylaxis and treatment of periodontal diseases should be of great importance in the COPD therapy, which may increase its effectiveness.

Potential impact of subject-based risk factor control on periodontitis

AIMS

To assess the potential impact of the control of subject-based modifiable risk factors on periodontitis.

BACKGROUND

Cross-sectional and longitudinal data from epidemiological research indicate that risk factors can be identified and, if modified, may improve both periodontal conditions and the outcome of treatment.

MATERIAL AND METHODS

A search was conducted to identify factors involved in the etiology and pathogenesis of periodontal diseases. The factors identified were separated into modifiable and non-modifiable, and control of the subject-based modifiable risk factors were further analyzed.

RESULTS

The analysis was limited to the influence of the control of the remaining modifiable subject-based risk factors. It was observed that most of the subject related risk factors were hitherto not validated in controlled intervention studies. Therefore, the evidence for the efficacy of risk factor control had to be based on results from cohort studies. While the control of most of the modifiable risk factors for periodontitis was not tested, some evidence suggested that smoking cessation may retard the progression of periodontitis.

CONCLUSIONS

Although only limited evidence was available, it appeared reasonable to suggest that second to the removal of the bacterial biofilm, smoking cessation was the most important measure in the management of periodontitis.

Cost-benefit, cost-effectiveness and cost-utility analyses of periodontitis prevention

OBJECTIVE

The aim of this paper was to determine whether there is evidence that periodontitis prevention is economically justified.

MATERIAL AND METHODS

The characteristics of economic assessments such as cost-benefit, cost-effectiveness and cost-utility analyses were first derived from the literature on health economy. A literature search was conducted using PubMed up to December 2004. Inclusion criteria required that economic analyses be based on scientific principles including a hypothesis, valid comparative groups as well as a cost/benefit, cost/effectiveness and cost/utility assessment.

RESULTS

Only 14 papers were located, which included, in the broadest sense, economic parameters. From these papers, three were systematic reviews, three were randomized controlled studies, four were controlled studies, one was a longitudinal cohort study and three papers were based on statistical modelling. Only one paper reported actual costs for periodontal and dental treatment. Extensive programmes aimed at prevention of periodontal disease in a general population group showed no economic benefit. Adjunctive genetic/and or microbiological testing likewise showed no economic benefit. Economic assessments and real costs are not generally available in the literature. Statistical modelling suggested that non-surgical periodontal procedures are more economical compared with surgical interventions. The use of local delivery devices as an adjunct to Sc/RP showed no economic advantage.

CONCLUSION

It is suggested that economic parameters as well as patient-centred outcomes be included in clinical trials. These data are essential for the appropriate allocation of resources for preventive measures on an individual patient and population base.

Immune responses and vaccination against periodontal infections

BACKGROUND

The infectious aetiology of periodontitis is complex and no curative treatment modality exists. Palliative therapy is available.

AIMS

To review the evidence that active or passive immunization against periodontitis provides immune protection.

MATERIAL AND METHODS

PubMed (Medline), the National Institutes of Health, the Food and Drug Administration, and the Center for Disease Control electronic databases were searched to extrapolate information on immune responses to immunization against periodontitis.

RESULTS

Studies in non-human primate models using ligature-induced experimental periodontitis suggest that antibody responses by active immunization against Porphyromonas gingivalis can safely be induced, enhanced, and obtained over time. Immune responses to whole bacterial cell and purified protein preparations considered as vaccine candidates have been evaluated in different animal models demonstrating that there are several valid vaccine candidates. Data suggest that immunization reduces the rate and severity of bone loss. It is also, temporarily, possible to alter the composition of the subgingival microflora. Natural active immunization by therapeutic interventions results in antibody titre enhancement and potentially improves treatment outcomes. Passive immunization of humans using P. gingivalis monoclonal antibodies temporarily prevents colonization of P. gingivalis. Probiotic therapy may be an alternative approach. Regulatory and safety issues for human periodontal vaccine trials must be considered. Shared infectious aetiology between periodontitis and systemic diseases may enhance vaccine effort developments.

CONCLUSIONS

Proof of principle that active and passive immunization can induce protective antibody responses is given. The impact of natural immunization and passive immunization in humans should be explored and may, presently, be more feasible than active immunization studies.

Inflammation in periodontal tissues in response to mechanical forces

Orthodontic forces are known to produce mechanical damage and inflammatory reactions in the periodontium and dental pulp, as well as inflammatory mediators, e.g. prostaglandins, interleukin (IL)-1, IL-6, tumor necrosis factor alpha, and receptor activator of nuclear factor kappaB ligand, in the periodontal ligament (PDL) and dental pulp. We have studied the effects of aging on the production of inflammatory mediators in the PDL using in vitro and in vitro methods and found that aging of PDL tissues may be an important factor in the severity of periodontal disease through a higher production of inflammatory mediators in response to mechanical forces. Further, the levels of inflammatory mediators in gingival crevicular fluid, an osmotically mediated inflammatory exudates found in the gingival sulcus, have been shown to be significantly elevated during orthodontic treatment. In order to reduce inflammation, low-level laser therapy has been recently studied in vitro and in vitro by many investigators as a substitute for anti-inflammatory drugs. Clinical and experimental studies have shown that low-level laser irradiation reduces orthodontic post-adjustment inflammation. We believe that orthodontic forces (mechanical forces) may play an important role in periodontal inflammation and that low-level laser therapy may be useful for its inhibition.

[Risk assessment for preterm delivery in pregnant women with active periodontitis]

INTRODUCTION

Premature labor has been regarded as a highly problematic clinical event not only due to its relation with perinatal mortality but also in the light of the remote results of the prematurity. Therefore many ongoing studies concentrate on evaluation of potentially avoidable risk factors of premature labor. Relatively few studies have suggested chronic periodontitis as such a determinant.

OBJECTIVES

Prospective evaluation of periodontium changes in the course of otherwise normal pregnancy. Assessment of potential influence of periodontium pathology, and its severity, on the obstetrical complications. The authors have made literature search on the relation of active periodontitis and premature labor.

MATERIALS AND METHODS

Study involved 120 randomized gravidae attending electively dental clinic for a routine control.

INCLUSION CRITERIA

single pregnancy, no preterm delivery in a history, mother's age 18 to 35 years, gestational age 10 to 20 weeks based on a last menstrual period date--confirmed on ultrasound. Every patient underwent dental examination twice--at the inclusion date and 48 hours after delivery. Patients were divided into three groups. Group I (n = 25)--healthy patients. Group II (n = 61)--patients with mild or moderate periodontitis. Group III (n = 39) patients with a severe periodontitis. Progression of lesions was recognized if the post-delivery dental assessment revealed increase of the pockets depth higher than 2mm and in at least 4 places compared with the initial findings.

RESULT

In the course of otherwise normal pregnancy women with signs of inflammation within periodontium revealed progression of this pathology proportional to its severity in early pregnancy. This increase was associated with 4-fold higher rate of preterm deliveries in Group II and 12-fold in Group III compared with healthy patients.

CONCLUSION

Active and severe periodontitis should be regarded as independent and highly influential risk factor of the preterm delivery.

Periodontitis and Three Health-Enhancing Behaviors: Maintaining Normal Weight, Engaging in Recommended Level of Exercise, and Consuming a High-Quality Diet

BACKGROUND

Maintaining normal weight, engaging in the recommended level of exercise, and eating healthy food are known to improve general health. The impact of these behaviors on periodontal health is not well documented. This study is aimed at examining whether the increased number of these behaviors is associated with a decrease in the prevalence of periodontitis in a United States population.

METHODS

This study utilized data on 12,110 individuals who participated in the third National Health and Nutrition Examination Survey. Multivariate logistic regression analysis was used to estimate the association between the number of health-enhancing behaviors and periodontitis prevalence. Health enhancing behaviors included maintaining normal weight (body mass index [BMI], 18.5 to 24.9 kg/m(2)), engaging in the recommended level of exercises (>or=episodes of moderate or >or=episodes of vigorous-intensity physical activity per week), and having a high-quality diet (healthy eating index >80).

RESULTS

After controlling for age, gender, race\ethnicity, cigarette smoking, other tobacco products, education, diabetes, poverty index, census region, acculturation, vitamin use, time since the last dental visit, dental calculus, and gingival bleeding, a 1-unit increase in the number of the three health-enhancing behaviors was associated with a 16% reduction in the prevalence of periodontitis (odds ratio [OR]=0.84; 95% confidence interval [CI]: 0.77 to 0.93). Individuals who maintained normal weight, engaged in the recommended level of exercise, and had a high-quality diet were 40% less likely to have periodontitis compared to individuals who maintained none of these health-enhancing behaviors.

CONCLUSION

An increased number of health-enhancing behaviors is associated with a lower periodontitis prevalence.

Evaluation of a monovalent companion animal periodontal disease vaccine in an experimental mouse periodontitis model

Periodontal disease in companion animals is clinically similar to that of human periodontal disease. Despite the usage of veterinary procedures and antibiotic therapy, the disease still remains as one of the most highly prevalent disorders seen by veterinarians. The goal of this study was to evaluate the immunogenic properties and vaccine performance of a monovalent canine periodontal disease vaccine in the mouse oral challenge model of periodontitis. Mice vaccinated subcutaneously with inactivated, whole-cell bacterin preparations of Porphyromonas gulae displayed both high titers of anti-P. gulae specific antibodies and significantly reduced alveolar bone loss in response to homologous, heterologous, and cross-species challenge. Based on the results of these studies, a periodontal disease vaccine may be a useful tool in preventing the progression of periodontitis in animals.

Prevention of periodontal diseases

The ultimate goal of periodontal disease prevention is to maintain the dentition over a lifetime in a state of health, comfort, and function in an aesthetically pleasing presentation. This article focuses on primary and secondary periodontal disease prevention as they relate to gingivitis and periodontitis. Risk assessment, mechanical plaque control, chemical plaque control, current clinical recommendations for optimal prevention, and future preventive strategies are discussed.

[Preliminary study on anti-periodontitis immunization with DNA vaccine]

OBJECTIVE

To observe the protection against periodontal bone loss in the Sprague-Dawley (SD) rats periodontitis model, with the recombined plasmid pcDNA3.1+/kgpcd as DNA gene vaccine.

METHODS

PcDNA3.1+/kgpcd was delivered into rats by submandibular gland-targeted injection. The anti-KGPcd sIgA in saliva was measured by indirect ELISA method. Immunohistochemistry staining was used to assess the protection in the animal model.

RESULTS

The level of specific anti-KGPcd sIgA in saliva of the experimental group was significantly higher than that of control group. HE staining showed that immunization with recombined plasmid pcDNA3.1+/kgpcd could protect or minimize tissue destruction caused by subsequent P. gingivalis challenge in the rat model.

CONCLUSIONS

The results indicate that pcDNA3.1+/kgpcd was a good candidate for anti-periodontitis gene vaccine and could provide protection against Porphyromonas gingivalis-caused periodontitis in rat lesion model.

Future treatment and diagnostic strategies for periodontal diseases

Many new technologies have been developed or are being developed that could enhance the ability to diagnose, predict, and treat periodontitis. Newer treatment strategies may allow clinicians to achieve limited or more robust regeneration of the periodontium. New or refreshed approaches to disease control are being pursued that will benefit those suffering from chronic periodontal disease. In addition to novel therapeutics, there has been increasing focus on the development of more sensitive and specific diagnostic tests for periodontal diseases. Such tests will allow the clinician to determine whether a patient has active disease and what sort of attachment loss might be expected if the patient is not treated. By developing newer diagnostic tests, it also may be possible to detect and monitor active disease during therapy.

Reduced development of experimental periodontitis by treatment with M40403, a superoxide dismutase mimetic

M40403, [manganese(II)dichloro[(4R,9R,14R,19R)-3,10,13,20,26 pentaazatetracyclo[20.3.1.0.(4,9)0(14,19)]hexacosa-1(26),-22(23),24-triene]], is a low-molecular-weight, synthetic, manganese-containing superoxide dismutase mimetic that removes superoxide anions without interfering with other reactive species known to be involved in inflammatory responses (e.g., nitric oxide, NO and peroxynitrite, ONOO-). As such, M40403 represents an important pharmacological tool to dissect the roles of superoxide anion in acute and chronic inflammation. For this purpose, the pharmacological profile of M40403 was evaluated in a rat model of periodontitis. Periodontitis was induced in rats by placing a 2/0 braided silk around the lower left first molar. On day 8 the gingivomucosal tissue encircling the first molar was removed for biochemical and histological analysis. Ligation significantly increased inducible nitric oxide synthase activity and expression, and gingival tissue revealed increased neutrophil infiltration, lipid peroxidation and positive staining for nitrotyrosine formation and poly (ADP-ribose) polymerase activation. Ligation significantly increased Evans blue extravasation in gingivomucosal tissue and alveolar bone destruction. Intraperitoneal injection of M40403 (10 mg/kg daily for 8 days) significantly decreased all of the above-described markers of inflammation. This suggests compounds that inhibit the generation of superoxide anion, such as M40403 may be potentially useful for the treatment of periodontitis.