Modeling the relationship between clinical, microbiologic, and immunologic parameters and alveolar bone levels in an elderly population

Advancements in Methods of Classification and Measurement Used to Assess Tooth Mobility: A Narrative Review

Evaluating tooth mobility is clinically significant, not only for diagnosing periodontal tissues but also in determining the overall periodontal treatment plan. Numerous studies related to tooth mobility have been conducted over the years, including the proposal of various classifications as well as the development of electronic devices for objective measurement. However, there is still no consensus on the measurement methods and criteria for assessing tooth mobility. In this study, we provide a comprehensive review of past and current tooth mobility classification and measurement methods. In order to propose a new method to intuitively evaluate tooth mobility based on previous studies, a digital approach capable of recording tooth micromovements induced by dynamic load should be considered.

Immunomodulation—What to Modulate and Why? Potential Immune Targets

Despite over 50 years of research into the immunology of periodontal disease, the precise mechanisms and the role of many cell types remains an enigma. Progress has been limited by the inability to determine disease activity clinically. Understanding the immunopathogenesis of periodontal disease however is fundamental if immunomodulation is to be used as a therapeutic strategy. It is important for the clinician to understand what could be modulated and why. In this context, potential targets include different immune cell populations and their subsets, as well as various cytokines. The aim of this review is to examine the role of the principal immune cell populations and their cytokines in the pathogenesis of periodontal disease and their potential as possible therapeutic targets.

Oral Osteomicrobiology: The Role of Oral Microbiota in Alveolar Bone Homeostasis

Osteomicrobiology is a new research field in which the aim is to explore the role of microbiota in bone homeostasis. The alveolar bone is that part of the maxilla and mandible that supports the teeth. It is now evident that naturally occurring alveolar bone loss is considerably stunted in germ-free mice compared with specific-pathogen-free mice. Recently, the roles of oral microbiota in modulating host defense systems and alveolar bone homeostasis have attracted increasing attention. Moreover, the mechanistic understanding of oral microbiota in mediating alveolar bone remodeling processes is undergoing rapid progress due to the advancement in technology. In this review, to provide insight into the role of oral microbiota in alveolar bone homeostasis, we introduced the term “oral osteomicrobiology.” We discussed regulation of alveolar bone development and bone loss by oral microbiota under physiological and pathological conditions. We also focused on the signaling pathways involved in oral osteomicrobiology and discussed the bridging role of osteoimmunity and influencing factors in this process. Finally, the critical techniques for osteomicrobiological investigations were introduced.

Self-Perception of Periodontal Health and Associated Factors: A Cross-Sectional Population-Based Study

The aim of this cross-sectional study was to explore sociodemographic, behavioral, and clinical factors associated with self-awareness of periodontal health. Data were collected from a representative sample of 736 adults (25–75 years old) in a city of Northern Italy who self-assessed gingival bleeding, oral malodor, and tooth mobility in a questionnaire and who underwent clinical periodontal examination and organoleptic evaluation. Approximately 50% of the subjects were aware of their actual gingival health status and oral odor. The logistic regression analysis revealed that females presented higher odds of correctly perceiving their gingival conditions and mouth odor, while those who were older and smokers had a greater probability of being less objective in reporting them. Tooth type and position in the dental arches were positively associated with self-perception of tooth mobility. These findings reflected a low level of self-awareness that may influence oral care-seeking behavior. Subjects may be unconcerned about their periodontal health condition or lack enough knowledge to be aware of it. This points to the need for planning strategies to improve education and knowledge about periodontal health, which, by enhancing self-perception of periodontal symptoms, could help everyone to seek treatment in the initial stage of the disease.

The emerging roles of B cells as partners and targets in periodontitis

Initial studies of periodontal disease suggested that T cell-mediated immunity against oral Gram-negative microorganisms is a key player in the pathogenesis of this inflammatory disease. Recent investigations, however, revealed that B cells are also engaged. Given their chief role in innate-like and adaptive immune responses, B cells could exert protective functions in periodontitis. However, the periodontal bacteria-specific antibody response is generally unable to halt disease progression in affected subjects, suggesting that the antibodies produced could exhibit low anti-bacterial blocking functions or opsonophagocytic potential, and/or unfavorable effects. Moreover, although microbial antigens are involved in the induction of the inflammatory responses in human adult periodontitis, endogenous antigens also may contribute to the chronicity of this common disease. Not only antibodies to self-antigens, such as collagen, are locally produced, but the autoreactivities observed in aggressive periodontitis are more severe and diverse than those observed in chronic periodontitis, suggesting that autoimmune reactivity could play a role in the tissue destruction of periodontal disease. Further support for a pathological role of B cells in periodontitis comes from the finding that B cell-deficient mice are protected from bacterial infection-induced alveolar bone loss. Studies in patients indicate that B cells and plasma cells, together with osteoclastogenic factors (RANKL and osteoprotegerin) and specific cytokines involved in their growth and differentiation (BAFF and APRIL) participate in the induction of the pathological bone loss in periodontitis. This novel insight suggests that selective targeting of B cells could represent a future therapeutic avenue for severe periodontal disease.

The role of osteoimmunology in periodontal disease

Periodontal disease is a pathological condition that involves inflammation of the tooth supporting structures. It occurs in response to the presence of bacterial plaque on the tooth structure. The host defense system, including innate and adaptive immunity, is responsible for combating the pathologic bacteria invading the periodontal tissue. Failure to eradicate the invading pathogens will result in a continuous state of inflammation where inflammatory cells such as lymphocytes, PMNs, and macrophages will continue to produce inflammatory mediators in an effort to destroy the invaders. Unfortunately, these inflammatory mediators have a deleterious effect on the host tissue as well as foreign microbes. One of the effects of these mediators on the host is the induction of matrix degradation and bone resorption through activation of proteases and other inflammatory mediators that activate osteoclasts.

Autoimmune responses in periodontal diseases

Periodontal diseases are characterized by localized infections and inflammatory conditions and directly affect teeth supporting structures which are the major cause of tooth loss. Several studies have demonstrated the involvement of autoimmune responses in periodontal disease. Evidences of involvement of immunopathology have been reported in periodontal disease. Bacteria in the dental plaque induce antibody formation. Lymphocytes, cytokines and complement system are reported to have an important role in the progression of periodontal disease. The present review describes the involvement of autoimmune responses in periodontal diseases. The mechanisms underlying these responses are also discussed.

Age-related disruption of the lamina dura: evidence in the mandibular horizontal incompletely impacted third molar

Changes in the lamina dura are associated with dental diseases around the root of the tooth and with systemic diseases; however, the lamina dura below the crown of horizontal, incompletely impacted third molars has not been studied. Using orthopantomography, we studied the age of subjects with and without the lamina dura in 419 subjects. The participants were between the ages of 21 and 89 years. Mean age in men with the lamina dura was 30.29 ± 9.92 and without the lamina dura was 47.64 ± 16.32 (P < 0.0001), and in women with a lamina dura it was 29.65 ± 8.19 and without a lamina dura 41.97 ± 11.07 (P < 0.0001). To study the effect of aging, the relationship between the lamina dura and dental status was assessed in subjects over the age of 31 years. Alveolar bone resorption in the canine and the first molar of the ipsilateral mandible in subjects without the lamina dura was not significantly higher than in those with the lamina dura. There were no significant differences in the number of teeth lost, except in men, the number of treated teeth and the number of decayed teeth differed between groups. Disruption of the lamina dura was related to age, but with no alveolar bone resorption in the mandible.

Destructive periodontitis lesions are determined by the nature of the lymphocytic response

It is now 35 years since Brandtzaeg and Kraus (1965) published their seminal work entitled "Autoimmunity and periodontal disease". Initially, this work led to the concept that destructive periodontitis was a localized hypersensitivity reaction involving immune complex formation within the tissues. In 1970, Ivanyi and Lehner highlighted a possible role for cell-mediated immunity, which stimulated a flurry of activity centered on the role of lymphokines such as osteoclast-activating factor (OAF), macrophage-activating factor (MAF), macrophage migration inhibition factor (MIF), and myriad others. In the late 1970s and early 1980s, attention focused on the role of polymorphonuclear neutrophils, and it was thought that periodontal destruction occurred as a series of acute exacerbations. As well, at this stage doubt was being cast on the concept that there was a neutrophil chemotactic defect in periodontitis patients. Once it was realized that neutrophils were primarily protective and that severe periodontal destruction occurred in the absence of these cells, attention swung back to the role of lymphocytes and in particular the regulatory role of T-cells. By this time in the early 1990s, while the roles of interleukin (IL)-1, prostaglandin (PG) E(2), and metalloproteinases as the destructive mediators in periodontal disease were largely understood, the control and regulation of these cytokines remained controversial. With the widespread acceptance of the Th1/Th2 paradigm, the regulatory role of T-cells became the main focus of attention. Two apparently conflicting theories have emerged. One is based on direct observations of human lesions, while the other is based on animal model experiments and the inability to demonstrate IL-4 mRNA in gingival extracts. As part of the "Controversy" series, this review is intended to stimulate debate and hence may appear in some places provocative. In this context, this review will present the case that destructive periodontitis is due to the nature of the lymphocytic infiltrate and is not due to periodic acute exacerbations, nor is it due to the so-called virulence factors of putative periodontal pathogens.

Bacterial Species in Subgingival Plaque and Oral Bone Loss in Postmenopausal Women

BACKGROUND

Oral bacteria are widely recognized in the etiology of periodontal disease. We investigated the prevalence of subgingival bacterial infection with eight species, tested associations between infection and oral bone loss, and assessed potential confounding factors and effect modifiers of those associations in a large community-based cohort of postmenopausal women.

METHODS

A cross-sectional study of oral health and osteoporosis in 1,256 postmenopausal women recruited from the Buffalo, New York Women's Health Initiative Observational Study was conducted. Standardized dental radiographs were used to measure alveolar crestal height (ACH). Subgingival plaque samples were taken, and the presence of eight bacterial species was assessed by indirect immunofluorescent microscopy in each participant.

RESULTS

The most prevalent infection was Streptococcus sanguis (59.5%), followed by Prevotella intermedia (43.4%), Tannerella forsythensis (37.9%), Capnocytophaga sp. (36.9%), Eubacterium saburreum (32.7%), Campylobacter rectus (17.4%), Porphyromonas gingivalis (15.1%), and Fusobacterium nucleatum (14.2%). Infections with P. gingivalis, T. forsythensis, P. intermedia, and C. rectus were associated with an increased likelihood of having oral bone loss as measured by ACH, even after adjustment for age, smoking, and income. The body mass index (BMI) was a modifier of this association. Overweight women with T. forsythensis infection were more likely to have oral bone loss (OR = 3.37; 95% confidence interval [CI]: 2.08 to 5.46) than normal weight (OR = 1.27; 95% CI: 0.82 to 1.98) or obese (OR = 1.26, 95% CI: 0.72 to 2.20) women with T. forsythensis infection.

CONCLUSIONS

The prevalence of specific bacterial infections was determined for a large group of postmenopausal women. Those with infection were more likely to have oral bone loss. Further studies should investigate potential modifying effects of BMI and/or inflammatory factors.

Innate immune peptide LL-37 displays distinct expression pattern from beta-defensins in inflamed gingival tissue

Anti-microbial peptides produced from mucosal epithelium appear to play pivotal roles in the host innate immune defence system in the oral cavity. In particular, human beta-defensins (hBDs) and the cathelicidin-type anti-microbial peptide, LL-37, were reported to kill periodontal disease-associated bacteria. In contrast to well-studied hBDs, little is known about the expression profiles of LL-37 in gingival tissue. In this study, the anti-microbial peptides expressed in gingival tissue were analysed using immunohistochemistry and enxyme-linked immunosorbent assay (ELISA). Immunohistochemistry revealed that neutrophils expressed only LL-37, but not hBD-2 or hBD-3, and that such expression was prominent in the inflammatory lesions when compared to healthy gingivae which showed very few or no LL-37 expressing neutrophils. Gingival epithelial cells (GEC), however, expressed all three examined anti-microbial peptides, irrespective of the presence or absence of inflammation. Moreover, as determined by ELISA, the concentration of LL-37 in the gingival tissue homogenates determined was correlated positively with the depth of the gingival crevice. Stimulation with periodontal bacteria in vitro induced both hBD-2 and LL-37 expressions by GEC, whereas peripheral blood neutrophils produced only LL-37 production, but not hBD-2, in response to the bacterial stimulation. These findings suggest that LL-37 displays distinct expression patterns from those of hBDs in gingival tissue.

Tooth loss and pocket probing depths in compliant periodontally treated patients: a retrospective analysis

BACKGROUND/AIMS

This retrospective study determined the treatment outcomes of 142 compliant periodontal patients observed for at least 10 years at the University of Kiel. All patients had been treated for moderate to advanced periodontitis and regularly received supportive periodontal therapy (SPT).

METHODS

Patient- and tooth-related variables [tooth loss and pocket probing depth (PPD)] were analysed.

RESULTS

Of a total of 3353 teeth, 167 were extracted during active treatment and 99 during SPT, mainly for periodontal reasons. Forty-five per cent of the patients did not lose any teeth during 11.7 years of observation. Thirty-seven per cent underwent extractions during active treatment or SPT, 18% both during active periodontal therapy and SPT. Mean tooth loss per patient was 0.07 teeth/year during SPT. Mobility, furcation involvement, smoking, and prescription antibiotics had a negative impact on prognosis. Intraindividual differences in PPD were significant between single- and multirooted teeth with initial PPD > or = 4 mm at baseline, following active treatment and at the end of SPT, and between firm and mobile teeth at baseline. Interindividual differences in mean PPD were only significant between smokers and non-smokers at the end of the observation period.

CONCLUSIONS

Long-term maintenance of our patients was effective. Periodontal disease represented the major cause of tooth loss in a minority of the population.

Retrospective comparison of clinical variables between compliant and non-compliant patients

BACKGROUND

The aim of this retrospective study was to evaluate if patients with moderate to advanced periodontitis had comparable periodontal conditions at baseline and during supportive periodontal therapy (SPT) whether they were compliant or not.

METHOD

Patient-related variables were compared: age, tooth mobility, furcation involvement, number of teeth, pocket probing depth, plaque index. Compliant patients (n = 142) received complete periodontal treatment and were followed over at least 10 years (group A). Non-compliant patients either discontinued supportive periodontal therapy (n = 42, group B) or dropped out before or during periodontal surgery (n = 44, group C).

RESULTS

At baseline, there were no significant differences between the 3 groups except for mobility. During SPT, mean pocket probing depth and plaque index differed significantly.

CONCLUSION

These results indicate that non-compliant patients compared to compliant patients had similar periodontal conditions at baseline, but responded less favourably to periodontal surgery and maintenance.

"Checkerboard" assessments of periodontal microbiota and serum antibody responses: a case-control study

BACKGROUND

We explored the association between subgingival microbial profiles and serum IgG responses to periodontal microbiota in relation to clinical periodontal status.

METHODS

One hundred thirty-one (131) periodontitis patients aged 29 to 74 years (mean 51.8) were age- and gender-matched with 74 periodontally intact controls (range 26 to 77, mean 49.3). Smoking habits and health history were recorded and assessments of plaque, bleeding on probing, probing depth, and attachment level were performed at 6 sites per tooth on all present teeth, excluding third molars. Subgingival plaque samples were obtained from each tooth in one upper and one lower quadrant (maximum 14 samples/subject; 2,440 samples total) and analyzed with respect to 19 species by means of whole genomic DNA probes. Serum IgG antibodies against the same 19 species were assessed by an immunoassay.

RESULTS

Cases displayed an average of 22.7 teeth, 20.3 sites with probing depth > or =6 mm, and 18.9 sites with attachment loss > or =6 mm. Corresponding figures for controls were 27.1, 0.1, and 1.0, respectively. Heavy smoking was 3 times more frequent among cases than controls (32.1% versus 9.6%). Higher levels of Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens, Prevotella melaninogenica, Bacteroides forsythus, Fusobacterium nucleatum, Treponema denticola, Eubacterium nodatum, Peptostreptococcus micros, and Campylobacter rectus were found in cases and higher levels of Eikenella corrodens, Veillonella parvula, and Actinomyces naeslundii in controls. Cases displayed higher IgG levels against P. gingivalis and Actinobacillus actinomycetemcomitans, while controls displayed higher levels against F. nucleatum, T. denticola, E. nodatum, and Capnocytophaga ochracea. Positive correlations between bacterial colonization and antibody responses were identified for 9 species in controls. In cases, however, statistically significant correlations were observed for only 3 species out of which only one was positive (V. parvula). Both bacterial levels and antibody responses declined in ages over 55 years. A logistic regression employing selected elements of bacterial colonization and antibody responses as independent variables resulted in 81.1% correct diagnosis, with sensitivity of 83.1%, specificity of 77.8%, positive predictability of 86%, and negative predictability of 73.7%. Smoking did not reach statistical significance in this model.

CONCLUSION

A combined microbial colonization/antibody response profile can effectively discriminate between periodontitis patients and periodontally intact controls.

The impact of molecular genetics on oral health paradigms

As a result of our increased understanding of the human genome, and the functional interrelationships of gene products with each other and with the environment, it is becoming increasingly evident that many human diseases are influenced by heritable alterations in the structure or function of genes. Significant advances in research methods and newly emerging partnerships between private and public sector interests are creating new possibilities for utilization of genetic information for the diagnosis and treatment of human diseases. The availability and application of genetic information to the understanding of normal and abnormal human growth and development are fundamentally changing the way we approach the study of human diseases. As a result, the issues and principles of medical genetics are coming to bear across all disciplines of health care. In this review, we discuss some of the potential applications of human molecular genetics for the diagnosis and treatment of oral diseases. This discussion is presented in the context of the ongoing technological advances and conceptual changes that are occurring in the field of medical genetics. To realize the promise of this new molecular genetics, we must be prepared to foresee the possibilities and to incorporate these newly emergent technologies into the evolving discipline of dentistry. By using examples of human conditions, we illustrate the broad application of this emerging technology to the study of simple as well as complex genetic diseases. Throughout this paper, we will use the following terminology: Penetrance--In a population, defined as the proportion of individuals possessing a disease-causing genotype who express the disease phenotype. When this proportion is less than 100%, the disease is said to have reduced or incomplete penetrance. Polymerase chain reaction (PCR)--A technique for amplifying a large number of copies of a specific DNA sequence flanked by two oligonucleotide primers. The DNA is alternately heated and cooled in the presence of DNA polymerase and free nucleotides, so that the specified DNA segment is denatured, hybridized with primers, and extended by DNA polymerase. MIM--Mendelian Inheritance in Man catalogue number from V. McKusick's Mendelian Inheritance in man (OMIM, 1998).

Actinobacillus actinomycetemcomitans in destructive periodontal disease. Three-year follow-up results

BACKGROUND

Convincing data exist that A. actinomycetemcomitans is an etiologic agent of periodontal disease. The purpose of this longitudinal study was to evaluate A. actinomycetemcomitans as a diagnostic indicator for periodontal disease in treated and periodontally maintained patients.

METHODS

Following comprehensive mechanical/surgical and supportive amoxicillin plus metronidazole therapy in 13 subjects with A. actinomycetemcomitans-associated destructive periodontal disease, we monitored subgingival A. actinomycetemcomitans at 4 individual sites in each patient up to 3 years post-therapy. The periodontal status was determined, and A. actinomycetemcomitans levels were quantitatively enumerated on TSBV agar in CFU/ml. Six patients with a persistence of subgingival A. actinomycetemcomitans at each reexamination within 3 years post-therapy were selected to be at risk for minor periodontal treatment outcomes and further recurrence of periodontal disease (test group). Seven subjects with a complete suppression of A. actinomycetemcomitans at each post-therapy visit served as controls.

RESULTS

The periodontal parameters decreased from overall values of 6.39 mm (probing depth, PD) and 7.64 mm (clinical attachment level, CAL) at the outset to 3.81 mm (PD) and 5.62 mm (CAL) 2 years post-therapy (Friedman, P< or =0.05). At the 3-year reexamination, the PD/CAL scores increased to 4.03/5.78 mm. Among the 6 individuals (46%) with persistence of subgingival A. actinomycetemcomitans at the final 3-year visit (test group), periodontal status yielded increased levels of 4.45 mm (PD) and 6.60 mm (CAL). The control subjects (n = 7) revealed lower values of 3.67 mm (PD) and 5.09 mm (CAL). However, on a patient level, during the 3-year observational trial, the periodontal status of the 13 individuals was not statistically affected by subgingival infection with A. actinomycetemcomitans.

CONCLUSIONS

Although in advanced periodontal disease, comprehensive mechanical and antimicrobial treatment is an appropriate regimen for sustained improvement of periodontal health, long-term control of subgingival infection with A. actinomycetemcomitans could not be achieved. In the maintenance care of destructive periodontitis, the persistence of A. actinomycetemcomitans is not a diagnostic parameter for periodontal disease.

Tooth mobility and periodontal disease

Tooth mobility (TM) is an important feature of periodontal disease. This is evidenced by the large number of devices and methods of TM assessment that have been developed and tested. TM had been considered and investigated as an indirect measure of the functional condition of the periodontium as well as possible aggravating co-factor for periodontal disease.

Periodontal diseases: epidemiology

1. The interpretation of epidemiological data of periodontal disease is difficult, due to inconsistencies in the methodology used. It is not possible, therefore, to accurately assess if the prevalence of the periodontal diseases shows a world-wide decline. As long as the disease is assessed through accumulated clinical attachment loss, retention of the natural dentition in older ages entails increased prevalence in these cohorts. Contemporary epidemiological studies should ideally employ full-mouth examination of the periodontal tissues. Partial recording estimates are generally biased, especially when the prevalence of the disease is low. 2. Early-onset periodontitis is infrequent in all populations. Adult periodontitis is rather prevalent; however, advanced disease affects limited subfractions of the population (probably less than 10 to 15%). Although prevalence figures vary with race and geographic region, in most cases, the progression pattern of the disease seems compatible with the retention of a functional dentition throughout life. 3. Of a plethora of behavioral and environmental risk markers identified by multi-variate analysis, smoking and presence of certain subgingival microorganisms have been proven to be true risk factors. The same holds true for diabetes mellitus, a systemic condition that confers a risk for periodontal disease which is independent of the effect of other significant factors. 4. In certain cases, periodontal infections appear to have a systemic impact on the host. Most recent data indicate that periodontal disease may confer risk for coronary heart disease and pre-term low birth weight.

Peripheral blood leukocyte populations in the elderly with and without periodontal disease

Periodontal disease in the elderly has not been characterized. Initial reports suggest that the disease is common and severe. Deficiencies in the immune response have also been reported to occur in the elderly. Consequently it was hypothesized that aging-related changes in the immune response may contribute to the severity and occurrence of periodontal disease in the elderly. To test that hypothesis, the % and number of leukocytes and leukocyte subsets in the peripheral blood of elderly (65-75 years) subjects were tested and used as indicators of the immune potential of those individuals. Age and gender effects on several of the parameters tested were identified. With the exception of increased number of leukocytes in the elderly group with severe periodontal disease, no other alteration in the leukocyte parameters tested were identified. These results suggest that periodontal disease in the elderly was not associated with obvious changes in the leukocyte and leukocyte subsets in the peripheral blood due to aging.

Prognosis versus actual outcome. II. The effectiveness of clinical parameters in developing an accurate prognosis

The assignment of prognosis is one of the most important functions undertaken in clinical practice, yet there is little evidence to support the current decision-making process which is based on an outdated model of disease etiology and progression. This study evaluated 100 treated periodontal patients (2,484 teeth) under maintenance care for 5 years, with 38 of these patients followed for 8 years, to determine the relationship of assigned prognoses to the clinical criteria commonly used in the development of prognosis. The method of generalized estimating equations (GEE) for correlated data was utilized to determine the relationship of each clinical factor to the assignment of initial prognosis, improvement in prognosis at 5 years, and worsening in prognosis at 5 years. A multiple linear regression model was constructed for predicting initial prognosis based on initial clinical data. Increased probing depth, more severe furcation involvement, greater mobility, unsatisfactory crown-to-root ratio, malpositioned teeth, and teeth used as fixed abutments resulted in worse initial prognoses. The coefficients from this model were able to predict accurately the 5-year and 8-year prognoses 81% of the time. When teeth with "good" prognoses were excluded, the predictive accuracy dropped approximately 50%. Multiple logistic regression models indicated that improvement in prognoses and worsening in prognoses were both strongly associated with initial probing depth, initial furcation involvement, initial tooth malposition, and smoking when adjusted for initial prognosis. In addition, good hygiene was found to increase the probability of improvement in prognosis while initial mobility was found to decrease the likelihood of improvement in prognosis. Neither of these factors was found to be significant in worsening of prognosis. Smoking decreased the likelihood of improvement by 60% and doubled the likelihood of worsening in prognosis at 5 years. The results of this study indicate that some clinical factors used in the assignment of prognoses are clearly associated with changes in clinical condition over time. The data also demonstrated that the traditional approach for assigning prognoses is ineffective for teeth with an initial prognosis of less than good. Since most periodontally involved teeth are compromised, further work should include the development of a more effective method for assigning prognoses that is based on clear, objective clinical criteria.

Antibody responses to suspected periodontal pathogens in elderly subjects with periodontal disease

Little is known about the relationship of aging to periodontal disease. The immune response undergoes aging-related changes resulting in loss of functional capacity. The aim of this study was to investigate the relationship between levels of serum IgG antibodies against suspected periodontal pathogenic microorganisms to the presence or absence of periodontal disease in an elderly (65-75 yrs) population. From this study, we obtained information concerning: (1) the ability to differentiate elderly individuals without disease from those with disease by their levels of antibodies against periodontal pathogens and (2) which periodontal pathogen(s) triggered those responses. IgG anti- Porphyromonas gingivalis (strains W83 and 381) levels in the serum of elderly patients with severe periodontal disease were the only antibody responses measured which were elevated compared to the elderly control group of subjects with no periodontal disease. Anti- Prevotella intermedia IgG levels in both elderly patient groups were depressed compared to anti- P. intermedia levels in the young normal control subjects. Serum IgG antibody levels to six other plaque microorganisms did not differentiate between diseased and normal, elderly or young subjects. This data suggested that P. gingivalis was associated with periodontal disease in this elderly group of individuals and that those elderly individuals were able to respond with a normal IgG immune response.