Periodontal diseases in the United States population

Oral reconstructive and corrective considerations in periodontal therapy

This paper was prepared by the Research, Science and Therapy Committee of the American Academy of Periodontology. It is intended to provide information for the dental profession and other interested parties. The purpose of this paper is to provide a general overview of oral reconstructive and corrective procedures used in periodontal therapy. It is not intended to be a comprehensive review of this subject.

An immune response directed to proteinase and adhesin functional epitopes protects against Porphyromonas gingivalis-induced periodontal bone loss

Porphyromonas gingivalis, a pathogen associated with periodontitis, bound to fibrinogen, fibronectin, hemoglobin, and collagen type V with a similar profile to that of its major virulence factor, the cell surface RgpA-Kgp proteinase-adhesin complex. Using peptide-specific, purified Abs in competitive inhibition ELISAs and epitope mapping assays, we have identified potential adhesin binding motifs (ABMs) of the RgpA-Kgp complex responsible for binding to host proteins. The RgpA-Kgp complex and synthetic ABM and proteinase active site peptides conjugated to diphtheria toxoid, when used as vaccines, protected against P. gingivalis-induced periodontal bone loss in the murine periodontitis model. The most efficacious peptide and protein vaccines were found to induce a high-titer IgG1 Ab response. Furthermore, mice protected in the lesion and periodontitis models had a predominant P. gingivalis-specific IL-4 response, whereas mice with disease had a predominant IFN-gamma response. The peptide-specific Abs directed to the ABM2 sequence (EGLATATTFEEDGVA) protected against periodontal bone loss and inhibited binding of the RgpA-Kgp complex to fibrinogen, fibronectin, and collagen type V. Furthermore, the peptide-specific Abs directed to the ABM3 sequence (GTPNPNPNPNPNPNPGT) protected against periodontal bone loss and inhibited binding to hemoglobin. However, the most protective Abs were those directed to the active sites of the RgpA and Kgp proteinases. The results suggest that when the RgpA-Kgp complex, or functional binding motif or active site peptides are used as a vaccine, they induce a Th2 response that blocks function of the RgpA-Kgp complex and protects against periodontal bone loss.

Disease progression: identification of high-risk groups and individuals for periodontitis

AIMS

While the role of bacteria in the initiation of periodontitis is primary, a range of host-related factors influence the onset, clinical presentation and rate of progression of disease. The objectives of this review are (1) to present evidence for individual predictive factors associated with a patient's susceptibility to progression of periodontitis and (2) to describe the use of prognostic models aimed at identifying high-risk groups and individuals in a clinical setting.

METHODS

Relevant publications in the English language were identified after Medline and PubMed database searches. Because of a paucity of longitudinal studies investigating factors including clinical, demographic, environmental, behavioural, psychosocial, genetic, systemic and microbiologic parameters to identify individuals at risk for disease progression, some association studies were also included in this review.

FINDINGS AND CONCLUSIONS

Cigarette smoking is a strong predictor of progressive periodontitis, the effect of which is dose related. High levels of specific bacteria have been predictive of progressive periodontitis in some studies but not all. Diabetics with poor glycaemic control have an increased risk for progression of periodontitis. The evidence for the effect of a number of putative factors including interleukin-1 genotype, osteoporosis and psychosocial factors is inconclusive and requires further investigation in prospective longitudinal studies. Specific and sensitive diagnostic tests for the identification of individuals susceptible to disease progression are not yet a reality. While factors assessed independently may not be valuable in predicting risk of future attachment loss, the combination of factors in a multifactorial model may be useful in identifying individuals at risk for disease progression. A number of multifactorial models for risk assessment, at a subject level have been developed but require validation in prospective longitudinal studies.

The Effect of Platelet-Rich Plasma on the Coronally Advanced Flap Root Coverage Procedure: A Pilot Human Trial

BACKGROUND

Coronally advanced flap (CAF) has been shown to effectively treat gingival recession. Platelet-rich plasma (PRP), containing autologous growth factors, has been shown to promote soft tissue healing. Therefore, the purpose of this study was to evaluate the effects of PRP in combination with CAF.

METHODS

Twenty-four systemically healthy patients participated in this study. A single Miller's Class I buccal recession defect per patient was treated. These patients were randomly assigned into CAF or PRP + CAF groups. Clinical parameters included recession depth (RD), recession width (RW), gingival thickness (GT), width of keratinized tissue (WKT), clinical attachment level (CAL), probing depth (PD), plaque index (PI), wound healing index (WHI), and gingival index (GI). PRP was prepared from whole blood drawn prior to surgery and applied to root surfaces. Patients were followed at 2, 4, 12, and 24 weeks post-surgery.

RESULTS

Twenty-three patients completed the study. The RD at 24 weeks was significantly reduced from 2.9 +/- 0.5 to 0.5 +/- 0.6 mm in the CAF group (P < 0.05) and from 2.8 +/- 0.2 to 0.5 +/- 0.7 mm in the PRP + CAF group (P < 0.05). The mean root coverage was 83.5% +/- 21.8% in the CAF group and 81.0% +/- 28.7% in the CAF + PRP group (P > 0.05). Fourteen out of 23 patients (60.9%) experienced 100% root coverage at the 24-week postoperative follow-up.

CONCLUSION

Based on the results of this pilot study, the application of PRP in CAF root coverage procedure provides no clinically measurable enhancements on the final therapeutic outcomes of CAF in Miller's Class I recession defects.

Gingipain-Specific IgG in the Sera of Patients With Periodontal Disease Is Necessary for Opsonophagocytosis ofPorphyromonas gingivalis

BACKGROUND

Porphyromonas gingivalis is a primary etiologic agent of generalized aggressive periodontitis (GAgP), and gingipains, a group of cysteine proteinases, are critical virulence factors expressed by this organism. GAgP patients develop specific antibodies to gingipains; however, the function of these antibodies in the clearance of P. gingivalis infection is poorly understood.

METHODS

In this study, we defined the levels of gingipain-specific antibodies in GAgP patient sera and examined the ability of gingipain-specific antibodies to facilitate opsonophagocytosis of P. gingivalis by human polymorphonuclear leukocytes (PMNs) using a fluorescent phagocytosis assay.

RESULTS

GAgP patient sera possessed elevated levels of P. gingivalis-, arginine-gingipain (Rgp)A-, RgpB-, and lysine-gingipain (Kgp)-specific IgG (Kgp > RgpA > P. gingivalis > RgpB). Adsorption of GAgP sera with P. gingivalis whole organisms, RgpA, RgpB, and Kgp conjugated to sepharose beads reduced opsonophagocytosis of P. gingivalis by PMNs.

CONCLUSIONS

Our studies demonstrate that GAgP patient sera possess elevated levels of P. gingivalis- and gingipain-specific IgG. Furthermore, we show that gingipain antibodies promote uptake of P. gingivalis by PMNs, and our data suggest that gingipain-specific antibodies may be important for the control of P. gingivalis infections.

Analytical epidemiology of periodontitis

AIMS

To review the literature related to the analytical epidemiology of periodontitis generated over the past decade. This review does not deal with descriptive epidemiologic studies of the prevalence, extent and severity of periodontitis with respect to global geography, but focuses exclusively on analytical epidemiology issues, including the challenges posed by the use of different case definitions across studies, current theories and models of disease progression, and risk factors associated with the onset and progression of periodontitis.

METHODS

Relevant publications in the English language were identified after Medline and PubMed database searches.

FINDINGS AND CONCLUSIONS

There is a conspicuous lack of uniformity in the definition of periodontitis used in epidemiologic studies, and findings from different research groups are not readily interpretable. There is a lack of studies that specifically address the distinction between factors responsible for the onset of periodontitis versus those affecting its progression. Colonization by specific bacteria at high levels, smoking, and poorly controlled diabetes have been established as risk factors for periodontitis, while a number of putative factors, including specific gene polymorphisms, have been identified in association studies. There is a clear need for longitudinal prospective studies that address hypotheses emerging from the cross-sectional data and include established risk factors as covariates along with new exposures of interest. Intervention studies, fulfilling the "targeting" step of the risk assessment process, are particularly warranted. Obvious candidates in this context are studies of the efficacy of elimination of specific bacterial species and of smoking cessation interventions as an alternative to the traditional broad anti-plaque approach in the prevention and control of periodontitis. Ideally, such studies should have a randomized-controlled trial design.

Prevalence and trends in periodontitis in the USA: the [corrected] NHANES, 1988 to 2000

Trends in periodontal diseases in the USA have been documented for years. However, the results have been mixed, mostly due to different periodontal assessment protocols. This study examined change in the prevalence of periodontitis between the NHANES III and the NHANES 1999-2000, and differences in the prevalence of periodontitis among racial/ethnic groups in the USA. Analysis was limited to non-Hispanic black, non-Hispanic white, and Mexican-American adults aged 18+ yrs in the NHANES III (n=12,088) or the NHANES 1999-2000 (n=3214). The prevalences of periodontitis for the NHANES III and the NHANES 1999-2000 were 7.3% and 4.2%, respectively. In multivariable analyses, blacks were 1.88 times (95%CI: 1.42, 2.50) more likely to have periodontitis than whites surveyed in the NHANES III. However, the odds of periodontitis for blacks and Mexican-Americans did not differ from those for whites surveyed in the NHANES 1999-2000. Our findings indicate that the prevalence of periodontitis has decreased between the NHANES III and the NHANES 1999-2000 for all racial/ethnic groups in the USA.

Prevalence of Clinical Attachment Loss in Adolescents in Santo Domingo, Dominican Republic

BACKGROUND

Data on periodontal conditions in adolescents in the Dominican Republic are scarce. The aim of the present cross-sectional study was to estimate the prevalence of periodontal attachment loss among Dominican adolescents. This study did not attempt to classify the disease into aggressive and chronic periodontitis.

METHODS

A random sample of 2,007 Dominican adolescents was obtained. A probability, weighted sample was selected using a complex, multi-stage probability sampling design. The study was clustered in 26 schools and 106 classes. The study subjects were clinically examined under field conditions by a single calibrated examiner who measured gingival recession and probing depth at six sites per tooth, with subsequent calculation of clinical periodontal attachment level for each site.

RESULTS

The prevalence of clinical attachment loss > or = 1 mm was 49.5%, with the prevalence ranging between 48.7% and 50.2%, depending on age and gender. Clinical attachment loss > or = 2 mm was found in 15% of the students and attachment loss > or = 3 mm in 4.0% of the students. Logistic regression model revealed that only age significantly increased the probability of having clinical attachment loss.

CONCLUSION

We conclude that clinical attachment loss is common in adolescents in Santo Domingo, Dominican Republic, suggesting the necessity for improved standards of prevention, diagnosis, and treatment of these lesions.

Epidemiology and risk factors of periodontal diseases

Periodontal diseases are chronic inflammatory disorders encompassing destructive and nondestructive diseases of the periodontal supporting tissues of teeth. Gingivitis is a nondestructive disease ubiquitous in populations of children and adults globally. Aggressive periodontitis is characterized by severe and rapid loss of periodontal attachment often commencing at or after the circumpubertal age and is more prevalent among Latin Americans and subjects of African descent, and least common among Caucasians. Chronic periodontitis is a common disease and may occur in most age groups, but is most prevalent among adults and seniors world-wide. Approximately 48% of United States adults have chronic periodontitis, and similar or higher rates have been reported in other populations. Moderate and advanced periodontitis is more prevalent among the older age groups, and rates of 70% or more have been reported in certain populations. Chronic and aggressive periodontitis are multifactorial diseases caused primarily by dental plaque microorganisms, and with important modifying effects from other local and systemic factors. The study of the significance of demographic, environmental, and biologic variables is important for risk assessment and the control of periodontal diseases.

The National Institute of Dental and Craniofacial Research: research for the practicing dentist

BACKGROUND AND OVERVIEW

Established in 1948, the National Institute of Dental and Craniofacial Research (NIDCR) has helped transform dentistry into a profession that is based firmly in prevention and technological innovation. This article introduces the new NIDCR initiative in general dentistry practice-based research. It also highlights research supported by the NIDCR and its implications for dental practice in restorative dentistry, oral and systemic disease, stem cell research, salivary diagnostics, gene transfer therapy and pain.

CLINICAL IMPLICATIONS

The NIDCR supports research that will help guide the practitioner in the delivery of patient care and have a direct impact on the practice of dentistry.

Nonsurgical approaches for the treatment of periodontal diseases

This article reviews nonsurgical approaches for the management of periodontal diseases. A brief review of the pathogenesis of periodontitis allows the reader to identify the potential points of intervention. Assessment of risk factors for periodontitis and the potential for risk reduction are introduced as the first part of a three-pronged approach to therapy. Antimicrobial approaches, including the use of mechanical therapy, antiseptics, and antibiotics,are described next. Host modulatory therapy is addressed as the fi-nal component of the nonsurgical approach to periodontal therapy. Clinical applications of these nonsurgical options are presented as part of the treatment strategy.

Forty-Eight–Month Periodontal Attachment Loss Incidence in a Population-Based Cohort Study: Role of Baseline Status, Incident Tooth Loss, and Specific Behavioral Factors

BACKGROUND

The objectives of this study were to: 1) test hypotheses that behavioral factors, baseline clinical status, and incident tooth loss are significantly associated with attachment loss incidence (ALI) and 2) quantify the effect of incident tooth loss on conclusions made about ALI.

METHODS

The Florida Dental Care Study was a prospective study of persons > or =45 years old. In-person interviews and examinations were conducted at baseline and 48 months, with telephone interviews in between.

RESULTS

Of 560 persons with baseline and 48-month examinations, 22% of persons and 1.8% of teeth had ALI. This was highest among persons with no dental visit during follow-up (person-level incidence of 46%; 5.0% tooth-level incidence). Statistically significant covariates in a multivariable regression of ALI were: losing a tooth due to periodontal reasons after baseline, but before the 48-month examination; not receiving a dental cleaning; and baseline factors (worst attachment level of > or =7 mm, not flossing, a molar tooth, current smoker).

CONCLUSIONS

A substantial percentage of persons experienced ALI. Baseline attachment level and behavioral factors were significantly associated with ALI. Persons with incident tooth loss were also at increased risk for ALI, and teeth lost during follow-up had worse baseline attachment level. Had these teeth not been lost before the final examination, the ALI estimate could only have been higher. These findings demonstrate that those at greatest risk for ALI are least likely to enter the dental care system, and among those who do, one health outcome (tooth loss) can affect conclusions made about the incidence of another (ALI).

Identification of a new membrane-associated protein that influences transport/maturation of gingipains and adhesins of Porphyromonas gingivalis

The dual membrane envelopes of Gram-negative bacteria provide two barriers of unlike nature that regulate the transport of molecules into and out of organisms. Organisms have developed several systems for transport across the inner and outer membranes. The Gram-negative periodontopathogenic bacterium Porphyromonas gingivalis produces proteinase and adhesin complexes, gingipains/adhesins, on the cell surface and in the extracellular milieu as one of the major virulence factors. Gingipains and/or adhesins are encoded by kgp, rgpA, rgpB, and hagA on the chromosome. In this study, we isolated a P. gingivalis mutant (porT), which showed very weak activities of gingipains in the cell lysates and culture supernatants. Subcellular fractionation and immunoblot analysis demonstrated that precursor forms of gingipains and adhesins were accumulated in the periplasmic space of the porT mutant cells. Peptide mass fingerprinting and N-terminal amino acid sequencing of the precursor proteins and the kgp'-'rgpB chimera gene product in the porT mutant indicated that these proteins lacked the signal peptide regions, consistent with their accumulation in the periplasm. The PorT protein seemed to be membrane-associated and exposed to the periplasmic space, as revealed by subcellular fractionation and immunoblot analysis using anti-PorT antiserum. These results suggest that the membrane-associated protein PorT is essential for transport of the kgp, rgpA, rgpB, and hagA gene products across the outer membrane from the periplasm to the cell surface, where they are processed and matured.

A case-control study to investigate an association between adverse pregnancy outcome and periodontal disease

OBJECTIVES

The aim of this case-control study was to ascertain if women who experienced a preterm (or premature) birth had any differences in periodontal disease severity compared with women who delivered at term.

MATERIAL AND METHODS

Subjects were recruited postpartum. Case subjects delivered a baby before 37 weeks of gestation whereas control subjects gave birth at or around term. A questionnaire was administered by a Research Midwife, designed to collect demographic information, pregnancy outcome variables and information on other factors which may influence health in pregnancy. A periodontal examination was then performed at the bedside.

RESULTS

Demographic variables were similar between case and control subjects. There was a higher proportion of case subjects who reported smoking. There were no differences in oral hygiene, bleeding on probing or loss of attachment; however, control subjects had a higher proportion of periodontal pockets probing 5 mm or greater.

CONCLUSIONS

There was no association between the severity of periodontal disease and pregnancy outcome in this population.

Modulation of Clinical Expression of Plaque-Induced Gingivitis: Interleukin-1 Gene Cluster Polymorphisms

BACKGROUND

The purpose of the present study was to determine the association of interleukin-1 (IL-1) gene polymorphisms with clinical parameters of gingivitis in a large experimental gingivitis trial and with each of two subgroups, high responders (HR) and low responders (LR), with distinct susceptibility to gingivitis.

METHODS

Ninety-six systemically and periodontally healthy non-smokers, 46 males (mean age: 23.9+/-1.7) and 50 females (mean age: 23.3+/-1.6) were included in a randomized, split-mouth, localized 21-day experimental gingivitis trial. Plaque index (PI), gingival index (GI), gingival crevicular fluid volume (GCF), and angulated bleeding score (AngBS) were recorded. Two subgroups were defined from the total study population (HR, LR) characterized by substantially different severity of gingival inflammation despite similar plaque accumulation rate. The study population was typed for interleukin-1 alpha (IL-1A+4845), interleukin-1 beta (IL-1B+3953, IL-1B-511), and IL-1 receptor antagonist (IL-1RN, intron 2 variable number tandem repeats) gene polymorphisms. Gene variants were analyzed by amplifying the polymorphic region using polymerase chain reaction, followed by restriction-enzyme digestion and agarose gel electrophoresis.

RESULTS

Neither IL-1A+4845, IL-1B+3953, or the combined (IL-1A+4845 x 2 - IL-1B+3953 x 2) genotype was associated with clinical parameters in the overall population. IL-1RN was significantly associated with test quadrant PI (P= 0.046), GCF (P= 0.05), and GI (P= 0.018). The genotype distribution in HR and LR subjects was significantly different for IL-1RN (P= 0.045) and for IL-1B-511 (P= 0.023).

CONCLUSION

The results of the present study suggest an association between IL-1RN polymorphism and subject-based clinical behavior of the gingiva in response to de novo plaque accumulation, as well as a possible association between IL-1B-511 polymorphism and gingivitis susceptibility.

A prospective study to investigate the relationship between periodontal disease and adverse pregnancy outcome

OBJECTIVE

This study aimed to investigate a relationship between maternal periodontal disease and preterm birth, low birth weight and late miscarriage.

DESIGN

Prospective study in a single centre.

SETTING

Guy's and St Thomas' Hospital Trust, London, UK between August 1998 and July 2001.

SUBJECTS AND METHODS

Pregnant women were recruited on attending an ultrasound scan at approximately 12 weeks of pregnancy. Subjects completed a questionnaire and underwent periodontal examination.

MAIN OUTCOME MEASURES

Plaque and bleeding scores, pocket probing depth and loss of attachment. Pregnancy outcome data was collected retrospectively, including gestational age and birth weight at delivery.

RESULTS

Data were collected for 3,738 subjects. Regression analysis indicated that there were no significant relationships between the severity of periodontal disease and either preterm birth (PTB) or low birth weight (LBW). In contrast, there did appear to be a correlation between poorer periodontal health and those that experienced a late miscarriage.

CONCLUSIONS

There was no association between either preterm birth or low birth weight and periodontal disease in this population. There is evidence of a correlation between markers of poorer periodontal health and late miscarriage.

Periodontal epidemiology: towards social science or molecular biology?

Terms such as 'molecular epidemiology' and 'genetic epidemiology' have been coined to depict the change from 'traditional epidemiology', concerned with disease determinants at the community or society level, over to 'modern epidemiology', which is concerned with determinants operating at the individual level or even below, i.e. at the organ, tissue, cell, or molecular level. In this commentary, we point out to the limitations of this development and suggest that more emphasis is placed on making the presumed causal disease models explicit, when investigating the relationship between putative determinants and disease. Understanding the disease processes at the micro-level is insufficient for understanding disease at the individual level; and disease patterns at the population level cannot be understood unless it is realized that individuals exist in a variety of contexts that cannot be reduced to individual attributes.

A novel polymeric chlorhexidine delivery device for the treatment of periodontal disease

An implantable, anti-microbial delivery device for the treatment of periodontal disease has been developed. In this polymer-based delivery system, the encapsulation efficiency, release characteristics, and bioactivity of anti-microbial agent were controlled by the complexation of the drug with cyclodextrins of differing lipophilicity. Microparticles of poly(dl-lactic-co-glycolic acid) (PLGA) containing chlorhexidine (Chx) free base, chlorhexidine digluconate (Chx-Dg) and their association or inclusion complex with methylated-beta-cyclodextrin (MBCD) and hydroxypropyl-beta-cyclodextrin (HPBCD) were prepared by single emulsion, solvent evaporation technique. It was observed that encapsulation efficiency and release of the chlorhexidine derivatives from the microparticles was a function of the lipophilicity of the cyclodextrin. Complexation of the poorly water soluble Chx with the more hydrophilic HPBCD resulted in 62% higher encapsulation efficiency and longer duration of sustained release over a 2-week period than complexation with the more lipophilic MBCD. In contrast, the complexation of the more water-soluble derivative of chlorhexidine, Chx-Dg, with the more lipophilic MBCD improved encapsulation efficiency by 12% and prolonged its release in comparison to both the free Chx-Dg and its complex with HPBCD. Furthermore, it was observed that the initial burst effect could be diminished by complexation with CD. Preliminary studies have shown that the chlorhexidine released from PLGA chips is biologically active against bacterial population that is relevant in periodontitis (P. gingivalis and B. forsythus) and a healthy inhibition zone is maintained in agar plate assay over a period of at least a 1-week. The PLGA/CD delivery system described in this paper may prove useful for the localized delivery of chlorhexidine salts and other anti-microbial agents in the treatment of periodontal disease where prolonged-controlled delivery is desired.

Social factors and periodontitis in an older population

OBJECTIVES

We assessed the prevalences of periodontitis by education and income levels among US adults with data from the third National Health and Nutrition Examination Survey.

METHODS

The study was limited to non-Hispanic Blacks, Mexican Americans, and non-Hispanic Whites 50 years of age or older with a complete periodontal assessment during the dental examination.

RESULTS

Blacks with higher education and income levels had a significantly higher prevalence of periodontitis than their White and Mexican-American counterparts. The relationship between income level and periodontitis was modified by race/ethnicity. High-income Blacks exhibited a higher prevalence of periodontitis than did low-income Blacks and high-income Whites.

CONCLUSIONS

Our findings call attention to the importance of recognizing socioeconomic status-related health differences across racial/ethnic groups within the social, political, and historical context.

Porphyromonas gingivalis-specific immunoglobulin G prevents P. gingivalis-elicited oral bone loss in a murine model

Active immunization with Porphyromonas gingivalis whole-cell preparations has been shown to prevent P. gingivalis infection and oral bone loss. Employing passive antibody transfer and opsonization, we demonstrate with this study that immunization-elicited P. gingivalis-specific immunoglobulin G facilitates clearance of P. gingivalis in a subcutaneous chamber model and prevents P. gingivalis-elicited oral bone loss.

Modulation of clinical expression of plaque-induced gingivitis. II. Identification of "high-responder" and "low-responder" subjects

AIM

The aims of this study were to validate a randomized, split-mouth, localized experimental gingivitis model and to identify subjects with different gingivitis susceptibility.

MATERIAL AND METHODS

In each of 96 healthy subjects, one maxillary quadrant was randomly assigned as "test" (experimental gingivitis) and the contralateral quadrant as "control". Plaque index (PlI), gingival index (GI), gingival crevicular fluid volume (GCF), and angulated bleeding score (AngBS) were recorded in both quadrants at days 0, 7, 14, and 21. Cumulative plaque exposure (CPE), i.e. PlI over time, was calculated. Day-21 GCF was standardized according to CPE, and residuals of GCF on CPE were calculated. Two subpopulations were then defined, based on upper and lower quartiles of GCF-residual distribution and were, respectively, identified as "high-responder" (HR; n=24) and "low-responder" (LR; n=24).

RESULTS

At test quadrants, all parameters significantly increased throughout the trial, while in control quadrants, PlI, GI, and AngBS remained low. Significant differences were noted between test and control quadrants on days 7, 14, and 21 for all parameters. Significant increases in GI, AngBS, and GCF were observed in test quadrants over the course of the study in both HR and LR groups. Significant differences were noted between HR and LR groups for all gingivitis parameters on day 21 in test quadrants, without any significant differences in PlI or CPE between the groups.

CONCLUSIONS

We identified two subpopulations characterized by significant differences in clinical parameters of plaque-induced gingival inflammation, despite similar amounts of plaque deposits and plaque accumulation rates.

Modulation of clinical expression of plaque-induced gingivitis. III. Response of "high responders" and "low responders" to therapy

AIM

The aim of the present study was to characterize the subject-based clinical behavior of the gingiva in response to a tooth-cleaning regimen in two subpopulations, "high-responder" (HR) and "low-responder" (LR) groups, presenting a different inflammatory response to plaque accumulation.

MATERIAL AND METHODS

The study population comprised of 96 systemically and periodontally healthy subjects, 46 males and 50 females, non-smokers, enrolled in an experimental gingivitis trial. At completion of the experimental gingivitis period (day 21), all subjects were prescribed the same 21-day treatment regimen of amine/stannous fluoride (AmF/SnF(2))-containing toothpaste and mouthrinse. Plaque index (PlI), gingival index (GI), gingival crevicular fluid volume (GCF), and angulated bleeding score (AngBS) were recorded on three selected teeth. Treatment efficacy was evaluated in the overall population as well as in HR and LR groups, separately.

RESULTS

A statistically significant decrease of PlI was observed after treatment (p<0.001), with PlI reversing to baseline levels. Changes in PlI revealed the same trend in both HR and LR groups, without differences between groups. Treatment also resulted in a significant decrease of all gingivitis parameters (p<0.001 for all comparisons). After treatment, GI, AngBS, and GCF were comparable with baseline condition. However, when the two groups were compared, day 42-GCF was significantly higher in the HR group than the LR group.

CONCLUSIONS

A treatment regimen based on mechanical plaque control supplemented with AmF/SnF(2)-containing toothpaste and mouthrinse is effective in reducing plaque accumulation and re-establishing healthy gingival conditions after experimentally induced gingivitis, even in subjects with different inflammatory response to plaque accumulation.

Innate immune recognition of invasive bacteria accelerates atherosclerosis in apolipoprotein E-deficient mice

BACKGROUND

Infectious diseases have emerged as potential risk factors for cardiovascular disease (CVD). Epidemiological studies support a connection between periodontal disease, a chronic inflammatory disease of the supporting tissues of the teeth, and CVD.

METHODS AND RESULTS

To directly test the connection between periodontal disease and atherosclerosis, apoE-/- mice were orally challenged with the periodontal disease pathogen Porphyromonas gingivalis or an invasion-impaired P gingivalis fimbriae-deficient mutant (FimA-). Both wild-type P gingivalis and the FimA- mutant were detected in blood and aortic arch tissue of apoE-/- mice by PCR after challenge. ApoE-/- mice challenged with wild-type P gingivalis presented with increased atherosclerotic plaque and expressed the innate immune response markers Toll-like receptor (TLR)-2 and TLR-4 in aortic tissue. Despite detection of the FimA- mutant in the blood and in aortic arch tissue, apoE-/- mice challenged with the FimA- mutant did not present with periodontal disease, upregulation of TLRs, or accelerated atherosclerosis. Furthermore, we demonstrate that immunization to control P gingivalis-elicited periodontal disease concomitantly prevents P gingivalis-accelerated atherosclerosis.

CONCLUSIONS

We conclude that invasive P gingivalis accelerates atherosclerosis.

Modulation of clinical expression of plaque-induced gingivitis. I. Background review and rationale

OBJECTIVES

The purpose of this article is to provide the necessary background and rationale for the accompanying studies, which are ultimately aimed at identifying genetic and environmental factors determining gingivitis susceptibility.

MATERIALS AND METHODS

The literature on factors reported to modify the clinical expression of gingivitis, i.e., factors that determine individual variability in gingival inflammatory response to plaque, is presented.

RESULTS

Clinical evidence suggests that the gingival inflammatory response to plaque accumulation may differ substantially among individuals. However, most of the available studies are of small scale and not purposely designed to address the issue. Systemic factors implicated in modulation of the clinical expression of gingivitis include metabolic, genetic, environmental and other factors. The significance of such factors in designing and conducting a large-scale experimental gingivitis trial and means to account for them are discussed.

CONCLUSION

Although several factors have been implicated, genetic or environmental factors underlying differences in gingivitis expression are not fully elucidated. The accompanying studies aim to identify and characterize, among participants in a specifically designed large-scale experimental gingivitis trial, subjects that differ significantly in their gingival inflammatory response to plaque. This is the first step in an effort to determine genetic or environmental factors underlying such differences.

Position paper: periodontal diseases of children and adolescents

Children and adolescents are subject to several periodontal diseases. Although there is a much lower prevalence of destructive periodontal diseases in children than in adults, children can develop severe forms of periodontitis. In some cases, this destructive disease is a manifestation of a known underlying systemic disease. In other young patients, the underlying cause for increased susceptibility and early onset of disease is unknown. These diseases are often familial, suggesting a genetic predisposition for aggressive disease. Current modalities for managing periodontal diseases of children and adolescents may include antibiotic therapy in combination with non-surgical and/or surgical therapy. Since early diagnosis ensures the greatest chance for successful treatment, it is important that children receive a periodontal examination as part of their routine dental visits.

The Application of Multilevel Modeling in the Analysis of Longitudinal Periodontal Data – Part I: Absolute Levels of Disease

BACKGROUND

Statistical analyses of periodontal data that average site measurements to subject mean values are unable to explore the site-specific nature of periodontal diseases. Multilevel modeling (MLM) overcomes this, taking hierarchical structure into account. MLM was used to investigate longitudinal relationships between the outcomes of lifetime cumulative attachment loss (LCAL) and probing depth (PD) in relation to potential risk factors for periodontal disease progression.

METHODS

One hundred males (mean age 17 years) received a comprehensive periodontal examination at baseline and at 12 and 30 months. The resulting data were analyzed in two stages. In stage one (reported here), the absolute levels of disease were analyzed in relation to potential risk factors; in stage two (reported in a second paper), changes in disease patterns over time were analyzed in relation to the same risk factors. Each approach yielded substantially different insights.

RESULTS

For absolute levels of disease, subject-level risk factors (covariates) had limited prediction for LCAL/PD throughout the 30-month observation period. Tooth position demonstrated a near linear relationship for both outcomes, with disease increasing from anterior to posterior teeth. Sites with subgingival calculus and bleeding on probing demonstrated more LCAL and PD, and supragingival calculus had an apparently protective effect. Covariates had more "explanatory power" for the variation in PD than for the variation in LCAL, suggesting that LCAL and PD might be generally associated with a different profile of covariates.

CONCLUSION

This study provides, for a relatively young cohort, considerable insights into the factors associated with early-life periodontal disease and its progression at all levels of the natural hierarchy of sites within teeth within subjects.

Progression of destructive periodontal diseases in three urban minority populations: role of clinical and demographic factors

BACKGROUND, AIMS

Differences in prevalence, severity and risk factors for destructive periodontal diseases have been reported for ethnic/racial groups. However, it is not certain whether this disparity is due to ethnicity/race or factors associated with ethnicity/race. Therefore, the present study addressed whether the rates of disease progression and clinical and demographic factors associated with disease progression varied among three ethnic/racial groups.

METHODS

The study population consisted of 53 Asian-, 69 African- and 62 Hispanic-Americans. Clinical measurements included probing depth, attachment level, gingival erythema, bleeding upon probing, suppuration and plaque. Disease progression was defined as a > 2 mm loss of attachment 2 months post baseline. The demographic variables examined included occupational status, report of a private dentist, years resident in the United States and smoking history.

RESULTS

The rate of attachment loss for the entire population was 0.04 mm or 0.24 mm/year. No significant differences were found among the three ethnic/racial groups. Variables associated with subsequent attachment loss for the entire population were age, male gender, mean whole-mouth plaque, erythema, bleeding upon probing, suppuration, attachment loss and probing depth, and belonging to the "unskilled" occupational group. No differences in risk profiles were found among the 3 ethnic/racial groups. Using stepwise logistic regression analysis, a model was developed to relate the clinical and demographic variables examined with subsequent attachment loss. The model indicated that prior attachment loss, gingival erythema, suppuration, being a current smoker and belonging to the "unskilled" occupational group conferred high risk of > 1 site of attachment loss of > 2 mm.

CONCLUSIONS

The results of this study suggest that variables associated with ethnicity/race, such as occupational status, are largely responsible for the observed disparity in destructive periodontal disease progression in these populations.

Periodontal diseases: current and future indications for local antimicrobial therapy

The microbial etiology of gingivitis and periodontitis provides the rationale for use of adjunctive antimicrobial agents in the prevention and treatment of periodontal diseases. Although mechanical removal of supra- and subgingival calcified and non-calcified plaque deposits has been proved effective to control the gingival inflammatory lesions as well as to halt the progression of periodontal attachment loss, some patients may experience additional benefits from the use of systemic or topical antimicrobial agents. Such agents are able to significantly affect supra- and subgingival plaque accumulation and/or suppress or eradicate periodontal pathogenic microflora. Currently, properly selected local antiseptic and systemic antibiotic therapies can provide periodontal treatment that is generally effective, low-risk and affordable. This paper will briefly review the host-related conditions in which the periodontal preventive and therapeutic approaches may be effectively assisted by a local antimicrobial regimen. Potential future indications for adjunctive local antimicrobial therapy will also be discussed.

Improving oral health: current considerations

The high incidence of periodontal disease among adults in the Western world indicates that in most cases, routine dental care could be considerably improved. The progressive effect of the disease suggests that improvements in oral cleanliness are mandatory if large numbers of adults are to retain their teeth into old age. Data show that periodontal disease can be minimized through effective plaque control, and that a combination of brushing, interdental cleaning, and chemotherapeutic agents (e.g. mouthwash) is beneficial to patients with plaque control problems. The vast majority of adults do not follow an adequate home-care routine. Average brushing times are low, and only a minority of patients regularly floss. In addition, in those patients who do regularly brush and floss, a deterioration of plaque control occurs over time, suggesting that compliance is a major issue. The principal challenge for dental professionals is to identify how best to elicit an improvement.

Comparison of interleukin-1 genotypes in two populations with aggressive periodontitis

The genetic association of interleukin-1 (IL-1) with periodontitis has been investigated in different populations. Failure to detect an association with IL-1 genotypes in European Caucasians with aggressive periodontitis (AGP) has recently been reported. No data from Central American Hispanics are available. The purpose of this explorative study was to study the association between IL-1 genotypes and AGP in two populations. Ninety-one subjects, 28 North European patients and 33 controls together with 16 Central American patients and 14 controls were included in the study according to validated radiographic and clinical criteria. Two polymorphisms, IL-1alpha G(+4845)-T and IL-1beta C(+3954)-T were analysed by means of polymerase chain reaction-restriction fragment length polymorphism. The association between presence of specific genotypes and disease status was estimated by the odds ratio. A logistic regression was also used in order to investigate whether the occurrence of the disease depends upon the combination of the IL-1A and IL-1B alleles in the population. A similar distribution of genotypes between patients and controls in both populations was detected. The frequency of allele 1 of the IL-1A gene was higher in patients of both populations compared with controls, however, no statistical significant differences were found between patients and controls.

Association between level of education and oral health status in 35-, 50-, 65- and 75-year-olds

AIM

The aim of the present study was to evaluate the association between educational level and dental disease, treatment needs and oral hygiene habits.

MATERIAL AND METHODS

Randomized samples of 35-, 50-, 65- and 75-year-olds, classified according to the educational level: [low (LE): elementary school or higher (HE)], were identified. In 1091 subjects, a number of characteristics such as (i) number of teeth, (ii) periodontal attachment levels (PAL), (iii) caries and (iv) occlusal function were recorded. Educational level, oral hygiene and dietary habits were self-reported. Non-parametric variables were analyzed by chi2, Mann-Whitney U-Wilcoxon's rank sum tests, and parametric variables by Student's t-test (level of significance 95%). A two-way anova was performed on decayed, missing and filled surfaces to investigate the interaction between age and educational level. All statistical procedures were performed in the SPSS statistical package.

RESULTS

The number of remaining teeth was similar for LE and HE in the 35-year olds (25.8 versus 26.6), but in the older age groups LE had significantly a larger number of missing teeth. The LE groups (except in 65-year olds) exhibited significantly more PAL loss. LE had significantly fewer healthy gingival units in all but the 75-year age group. In all age groups, LE had fewer intact tooth surfaces and a significantly poorer occlusal function. The frequency of tooth cleaning measures and dietary habits did not differ between LE and HE.

CONCLUSION

Educational level was shown to influence the oral conditions and should be considered in assessing risk, and in planning appropriate preventive measures.

A systematic review on the use of residual probing depth, bleeding on probing and furcation status following initial periodontal therapy to predict further attachment and tooth loss

BACKGROUND

Chronic periodontitis affects many adults. Initial cause related therapy (ICRT) is aimed at elimination of factors causing disease progression.

OBJECTIVES

To use a systematic review process of peer reviewed publications to assess the predictive value of residual probing depths (PD), bleeding on probing (BOP) and furcation involvement (FI) in determining further loss of attachment and tooth loss following ICRT.

MATERIAL AND METHODS

An electronic search of the Cochrane Oral Health Group specialized register, MEDLINE and EMBASE, was performed using specific search terms to identify studies assessing the predictive value of residual probing depths (PD), bleeding on probing (BOP) and furcation involvement (FI) in determining further loss of attachment and tooth loss following ICRT.

RESULTS

The searches resulted in 941 uniquely identified studies. Titles and abstracts were then independently screened by two reviewers (S.R. and G.R.P.) to identify publications that met specific inclusion criteria. The agreement between the reviewers was assessed and statistical analysis failed to demonstrate a difference between the two reviewers (kappa-value: 0.94, P = 0.003). Detailed review of 47 included publications resulted in acceptance of one publication which utilized data based on patient as unit of observation. This study included 16 subjects over 42 months demonstrating that residual probing depths are predictive of further disease progression whereas persisting bleeding on probing are not.

CONCLUSIONS

Data based on one study suggest that residual probing depths are predictive of further disease progression. The implications for carefully designed multicentre randomized clinical control trials are many.

Immunization with Porphyromonas gingivalis capsular polysaccharide prevents P. gingivalis-elicited oral bone loss in a murine model

The capsular polysaccharide (CPS) of the periodontal pathogen Porphyromonas gingivalis is an important virulence factor for this organism. We purified P. gingivalis CPS, immunized mice with this antigen, and assessed the vaccine potential of P. gingivalis CPS by using the murine oral challenge model. Animals immunized with P. gingivalis CPS developed elevated levels of immunoglobulin M (IgM) and IgG in serum that reacted with whole P. gingivalis organisms. The mice immunized with P. gingivalis CPS were protected from P. gingivalis-elicited oral bone loss. These data demonstrate that P. gingivalis CPS is a vaccine candidate for prevention of P. gingivalis-elicited oral bone loss.

Influence of periodontal disease on Th1/Th2-type cytokines in saliva of HIV-positive individuals

Cytokines present during immune responses have a tremendous influence on resistance/susceptibility to oral diseases including periodontal disease and oral opportunistic infections in the immunocompromised individual, as seen by altered Th cytokines in saliva with human immunodeficiency virus (HIV) disease progression and oropharyngeal candidiasis. This study was designed to evaluate whether the presence of severe periodontal disease has any influence on Th cytokines in saliva of HIV-positive persons. For this, saliva from a cohort of HIV-positive persons with mild or severe periodontitis was evaluated for Th cytokines. A dominant Th2-type cytokine profile in saliva was validated in HIV-positive subjects with considerable immune suppression, irrespective of periodontal disease status. However, no significant differences in concentrations of Th1- or Th2-type cytokines in saliva were observed when stratified by periodontal status. Thus, the lack of salivary influences by periodontitis eliminates periodontal disease as a variable in interpretations regarding correlates of local cytokines during oral manifestations of HIV.

Epidemiologic risk factors for periodontal attachment loss among adults in the United States

OBJECTIVES

The objective of this study was to identify variables related to periodontal loss of attachment (LOA).

MATERIALS AND METHODS

The study population consisted of a nationally representative sample of 12,325 US adults who participated in the National Health and Nutrition Examination Survey III. The analyses used survey multinomial logistic regression to account for the complex survey design.

RESULTS

The adjusted odds ratio for a mean LOA of 3 mm or more associated with current smoking was 18.55 (95% CI 9.44-36.45) among 20-49-year olds. Among those aged 50 years or more, the odds ratio for a mean LOA of 4 mm or more was 25.64 (13.04-50.40). Prior smoking, untreated decayed surfaces (on both person and site levels), and male gender were also associated with LOA. There was no excess risk observed among non-Hispanic blacks or Mexican-Americans. The adjusted population attributable fractions due to current smoking were 60% for persons aged 20-49 with the worst 10% of LOA (1.58 mm or more), and 47% for those aged 50 plus (LOA of 3.39 mm or more).

CONCLUSION

These results support earlier findings regarding the central role of cigarette smoking in the etiology of periodontal loss of attachment, a role due in large part to the substantial relationship between smoking and severe periodontal disease.

Factors influencing the effect of race on established periodontitis prevalence

OBJECTIVE

This paper identifies differences in prevalence of established periodontitis and evaluates factors that might explain the differences between non-Hispanic African Americans (n = 232) and whites (n = 199) in the Detroit tricounty area.

METHODS

Subjects from a disproportionate probability sample of community-dwelling adults were interviewed regarding demographic, psychosocial and enabling factors, dental health-related behaviors, and other risk factors, and had comprehensive in-home dental examinations.

RESULTS

The overall prevalence of established periodontitis was 20.8 percent; African Americans exhibited a significantly higher prevalence than whites (29.8% vs 17.7%). The crude association between race and prevalence of established periodontitis was significant (odds ratio [OR] for African Americans = 1.98; 95% confidence interval [CI] = 1.17,3.34). After controlling for other covariates, we found the effect of race may be modified by dental checkup visit frequency: African Americans with dental checkups at least once a year had almost a fourfold higher odds of established periodontitis (OR = 3.64; 95% CI = 1.43, 9.24) than their white counterparts with dental checkups at least once a year (the referent group); while African Americans with a dental checkups once every two years or less often were more than fourfold less likely to have established periodontitis (OR = 0.22; 95% CI = 0.08, 0.59) than their white counterparts in the referent group.

CONCLUSIONS

This analysis supports the disparity in periodontal health as part of the black:white health disparity when taking other factors into account. However, periodontal health disparities may be more complex than previously recognized, requiring greater understanding of factors related to dental care utilization in future studies evaluating this disparity.

Immunization with the RgpA-Kgp proteinase-adhesin complexes of Porphyromonas gingivalis protects against periodontal bone loss in the rat periodontitis model

A major virulence factor of Porphyromonas gingivalis is the extracellular noncovalently associated complexes of Arg-X- and Lys-X-specific cysteine proteinases and adhesins designated the RgpA-Kgp complexes. In this study we investigated the ability of RgpA-Kgp as an immunogen to protect against P. gingivalis-induced periodontal bone loss in the rat. Specific-pathogen-free Sprague-Dawley rats were immunized with either formalin-killed whole P. gingivalis ATCC 33277 cells with incomplete Freund's adjuvant, RgpA-Kgp with incomplete Freund's adjuvant, or incomplete Freund's adjuvant alone. The animals were then challenged by oral inoculation with live P. gingivalis ATCC 33277 cells. Marked periodontal bone loss was observed in animals immunized with incomplete Freund's adjuvant alone; this bone loss was significantly (P < 0.05) greater than that detected in animals immunized with formalin-killed whole cells or RgpA-Kgp or in unchallenged animals. There was no significant difference in periodontal bone loss between animals immunized with formalin-killed whole cells and those immunized with RgpA-Kgp. The bone loss in these animals was also not significantly different from that in unchallenged animals. DNA probe analysis of subgingival plaque samples showed that 100% of the animals immunized with incomplete Freund's adjuvant alone and challenged with P. gingivalis ATCC 33277 were positive for the bacterium. However, P. gingivalis ATCC 33277 could not be detected in subgingival plaque samples from animals immunized with formalin-killed whole cells or with RgpA-Kgp. Immunization with formalin-killed whole cells or RgpA-Kgp induced a high-titer serum immunoglobulin G2a response. Western blot analysis of RgpA-Kgp using pooled protective antisera taken from rats immunized with RgpA-Kgp revealed immunodominant bands at 44, 39, and 27 kDa. In conclusion, immunization with RgpA-Kgp restricted colonization by P. gingivalis and periodontal bone loss in the rat.

[Prevalence of aggressive periodontitis in adolescents and young adults from Vale do Paraíba]

The aim of the present study was to determine the prevalence of localized and generalized aggressive periodontitis, as well as of incidental attachment loss, in a population of adolescents and young adults aging between 15 and 25 years (19.4 +/- 3.44) from Vale do Paraíba - SP, who searched for general dental care at the Department of Dentistry, University of Taubaté, São Paulo. Six hundred patients, 244 male and 356 female subjects, were included in the studied sample. The periodontal status of this population was evaluated by measuring the depth of periodontal pockets, as well as attachment loss. The data were confirmed by means of radiographic examination. Measurements were performed in six sites per tooth. Ten subjects (1.66%) were diagnosed as having localized aggressive periodontitis, 2 males (aging 18.5 +/- 2.12 years) and 8 females (aging 19.2 +/- 3.91 years); 22 (3.66%) presented with generalized aggressive periodontitis, 6 males (aging 19.1 +/- 3.06 years) and 16 females (aging 20.1 +/- 2.71 years); and 86 individuals (14.3%) presented with incipient periodontitis, 29 males (aging 20.2 +/- 2.87 years) and 57 females (aging 21.1 +/- 2.79 years). There was a positive correlation between the female gender and the occurrence of periodontal disease.

Evaluation of tuned-aperture computed tomography in the detection of simulated periodontal defects

OBJECTIVE

The objective of this study was to compare the diagnostic efficacy of tuned-aperture computed tomography (TACT) and conventional film for the detection of simulated periodontal defects.

STUDY DESIGN

Periodontal defects were created in 15 premolar-molar interproximal sites selected from 8 cadaver jaw segments. Ten observers viewed 45 image pairs (baseline and follow up) in 4 TACT modalities and film to assess the presence of defect. The TACT modalities were 1st and 2nd generation prototype systems (TACT-1 and TACT-2) with circular (C) and random (R) distribution patterns of source projection (TACT-1C, TACT-1R, TACT-2C, TACT-2R). Observer performance and related factors were analyzed by using receiver operating characteristic and analysis of variance.

RESULTS

Mean A(z) values were 0.64 for film, 0.74 for TACT-1C, 0.82 for TACT-1R, 0.64 for TACT-2C, and 0.69 for TACT-2R. TACT-1R was significantly better than film (P < .001), TACT-2C (P < .001) and TACT-2R (P = .007).

CONCLUSION

TACT-1R provided the best diagnostic performance in the detection of simulated periodontal defects among the 5 modalities compared in this study.

Clinical, radiographic and biochemical assessment of IL-1/TNF-alpha antagonist inhibition of bone loss in experimental periodontitis

OBJECTIVES

To assess clinical, radiographic, and biochemical markers as diagnostic indicators of disease activity by comparing ligature-induced bone loss in the presence or absence of IL-1/TNF-alpha antagonist inhibition of bone loss in a primate model.

MATERIAL AND METHODS

6 animals with a naturally-occurring gingivitis were evaluated over a 6-week time period following the placement of silk ligatures and initiation of a soft diet. Three animals received intrapapillary injections of soluble receptors (blockers), capable of blocking the biologic activity for both IL-1 and TNF-alpha, and 3 animals received vehicle (control) injections. Injections were given 3X per week over the course of the study. Clinical assessments included a gingival index and quantification of gingival crevicular fluid (GCF) levels. Collected GCF samples were then used in the biochemical assessment of pyridinoline (PYD) and bone alkaline phosphatase (BAP). Radiographic assessment was made using computer-assisted subtraction radiography to measure both bone density (CADIA) values and linear changes in crestal bone height.

RESULTS

Significant (p<0.01) changes using both radiographic measures occurred between 2 and 4 weeks following initiation of disease in this model. The use of the blockers significantly (p<0.01) reduced the levels of radiographic bone loss by approximately 50% over that found in the control sites. Both biochemical markers showed the greatest increase during the first two weeks of the study with PYD levels increased 35-fold over baseline levels after 1 week. This difference in response was significantly (p<0.05) greater than the levels found in the non-ligated teeth or in the ligated teeth receiving blockers injections. BAP levels showed significant increases in ligated teeth compared to non-ligated teeth, but failed to show any significant differences between animals treated with vehicle and those treated with IL-1/TNF antagonists. In contrast to these radiographic and biochemical effects, there were no significant differences detected between animals treated with antagonists and the control group for any of the clinical measures.

CONCLUSIONS

The results of this study demonstrate that both subtraction radiography and PYD crevicular fluid levels can detect relative differences in periodontal disease progression, while BAP crevicular fluid levels cannot.

Failure to detect an association with IL1 genotypes in European Caucasians with generalised early onset periodontitis

OBJECTIVES

In order to elucidate the genetic background to EOP it is useful to investigate associations with genetic polymorphisms of immune response genes, whose products play a r le in the inflammatory process. The aim of this study was to examine IL1A and IL1B genetic polymorphisms in unrelated European white Caucasian patients with generalised early-onset periodontitis (GEOP).

MATERIAL AND METHODS

Polymerase chain reaction (PCR) amplification of the ILIA (-889) gene and IL1B (+3953) gene (56 patients, 56 controls) was carried out and PCR products subjected to restriction fragment length polymorphism (RFLP) analysis.

RESULTS

There were no significant differences between patients and controls for any of the genotype or allele frequencies investigated (p = 1.0). Smoking status was also included as a covariate but this did not alter the results. Furthermore, expression of the composite genotype described by Kornman and coworkers was also investigated in these subjects. No significant differences were found between patients and controls whether smoking was included as a covariate or not.

CONCLUSION

The lack of any association between the IL1 polymorphisms and GEOP, in the population presented here, brings into doubt the usefulness of these candidate genes as markers of susceptibility to this form of periodontitis.

Treatment of gingival recessions by combined periodontal regenerative technique, guided tissue regeneration, and subpedicle connective tissue graft. A comparative clinical study

BACKGROUND

Many surgical techniques have been shown to be effective in correcting gingival recessions by covering the exposed root with soft tissue; however, the thickness of the gingival tissue over the root surface probably plays an important role in preventing the recurrence of tissue recession. The aim of the present study was to compare the results of a mucogingival bilaminar technique (BT), guided tissue regeneration (GTR), and a combined periodontal regenerative technique (CPRT) in achieving root coverage and increasing the gingival thickness 1 year after surgical treatment.

METHODS

In 45 systemically healthy, non-smoking patients aged 33.6 +/- 4.3 years with no periodontal pockets >4 mm, a Miller's Class I or II gingival recession was treated for root coverage: 15 patients underwent BT (connective tissue with partial-thickness double pedicle graft), 15 GTR by a bioabsorbable membrane, and 15 CPRT by a collagen membrane and collagen-incorporated hydroxyapatite. Before and 1 year after surgical treatments, the following clinical parameters were recorded: gingival recession (GR), probing depth (PD), clinical attachment level (CAL), keratinized tissue width (KT), and gingival thickness (GT); the percentage of root coverage was also calculated and the data were statistically analyzed.

RESULTS

All 3 techniques yielded significant improvements in terms of GR decrease, CAL and KT gain, and GT increase compared to baseline values. Mean root coverage was 90.0%, 81.01%, and 87.12% in BT, GTR, and CPRT groups, respectively. Complete root coverage was observed in 60%, 40%, and 53.3% of subjects from the BT, GTR, and CPRT groups, respectively. No significant differences were observed among the 3 techniques in GR or CAL improvements; however, BT produced a significantly (P<0.01) greater increase of KT, and BT and CPRT groups showed a significantly (P<0.01) greater increase of GT compared to the GTR group.

CONCLUSIONS

BT, GTR, and CPRT successfully treated gingival recession defects, obtaining comparable percentages of root coverage, but BT and CPRT created a thick gingival tissue significantly greater than that achieved with GTR.