Alternative methods for screening periodontal disease in adults

Emergence of Antibiotic-Resistant Porphyromonas gingivalis in United States Periodontitis Patients

Antibiotic resistance patterns of the major human periodontal pathogen Porphyromonas gingivalis were assessed over a 20-year period in the United States. Subgingival P. gingivalis was cultured pre-treatment from 2193 severe periodontitis patients during three time periods: 1999-2000 (936 patients), 2009-2010 (685 patients), and 2019-2020 (572 patients). The clinical isolates were tested for in vitro resistance to 4 mg/L for clindamycin and doxycycline, 8 mg/L for amoxicillin, and 16 mg/L for metronidazole, with a post hoc combination of data for metronidazole plus amoxicillin. Clindamycin-resistant P. gingivalis was significantly more prevalent in 2009-2010 (9.1% of patients) and 2019-2020 (9.3%; 15-fold increase) as compared to 1999-2000 (0.6%). P. gingivalis resistance to amoxicillin also significantly increased from 0.1% of patients in 1999-2000 to 1.3% in 2009-2010 and 2.8% (28-fold increase) in 2019-2020. P. gingivalis resistance to metronidazole, metronidazole plus amoxicillin, and doxycycline was low (≤0.5% prevalence), and statistically unchanged, over the 20-year period. These findings are the first to reveal marked increases over 20 years in clindamycin-resistant and amoxicillin-resistant P. gingivalis in United States periodontitis patients. Increased antibiotic resistance of P. gingivalis and other periodontitis-associated bacteria threatens the efficacy of periodontal antimicrobial chemotherapy.

Antibiotic Resistance of Human Periodontal Pathogen Parvimonas micra Over 10 Years

Changes were evaluated over 10 years in the in vitro resistance of human periodontopathic strains of Parvimonas micra to four antibiotics. Subgingival biofilms culture positive for P. micra from 300 United States adults with severe periodontitis in 2006, and from a similar group of 300 patients in 2016, were plated onto anaerobically incubated enriched Brucella blood agar alone, or supplemented with either doxycycline (4 mg/L), clindamycin (4 mg/L), amoxicillin (8 mg/L), or metronidazole (16 mg/L). P. micra growth on antibiotic-supplemented media indicated in vitro resistance to the evaluated antibiotic concentration. P. micra resistance was significantly more frequent among patients in 2016, as compared to 2006, for doxycycline (11.3% vs. 0.3% patients; 37.7-fold increase), and clindamycin (47.3% vs. 2.0% patients; 23.7-fold increase) (both p < 0.001), whereas resistance to amoxicillin (2.3% vs. 1.0% patients) and metronidazole (0% vs. 0.3% patients) remained low and statistically unchanged between the two patient groups (p-values > 0.05). No P. micra isolates in 2006 or 2016 were jointly resistant in vitro to both amoxicillin and metronidazole. The alarming increases in subgingival P. micra resistance to doxycycline and clindamycin raise serious questions about the empiric use of these antibiotics, either locally or systemically, in the treatment of United States periodontitis patients harboring subgingival P. micra.

Determination of sialic acid levels by using surface-enhanced Raman spectroscopy in periodontitis and gingivitis

OBJECTIVES

To compare the sialic acid (SA) levels in saliva among periodontitis-affected, gingivitis and control patients.

METHODS

The study involved 93 subjects. The participants were divided into three groups: (1) 30 subjects without periodontal disease (control group); (2) 30 subjects with gingivitis; and (3) 33 subjects with periodontitis. The oral parameters examined were as follows: (a) Simplified Oral Hygiene Index; (b) Calculus Index; (c) Gingival Index; (d) probing pocket depth; and (e) level of epithelial attachment. SA levels in saliva were measured by means of surface-enhanced Raman spectroscopy (SERS). This method has demonstrated the capacity to detect extremely low concentrations of molecules. The spectrum was calibrated using analytical reagent SA.

RESULTS

The obtained median values for SA concentrations were 5.98, 7.32, and 17.12 mg/dl for control, gingivitis, and periodontitis patients, respectively.

CONCLUSIONS

Our measurements by SERS corroborate that in periodontitis-affected patients, the SA concentration is larger than their concentrations in either control or gingivitis patients. This confirms previous reports and opens the possibility of using SERS as a diagnostic tool.

Characterization of periodontitis in people with type 1 diabetes of 50 years or longer duration

BACKGROUND

Periodontitis is more common and severe in people with diabetes than the general population. We have reported in the Joslin Medalist Study that people with type 1 diabetes of ≥50 years (Medalists) may have endogenous protective factors against diabetic nephropathy and retinopathy.

METHODS

In this cross-sectional study, the prevalence of periodontitis according to the Centers for Disease Control/American Academy of Periodontology classification in a subset (n = 170, mean age = 64.6 ± 6.9 years) of the Medalist cohort, and its associations to various criteria of periodontitis and diabetic complications were assessed.

RESULTS

The prevalence of severe periodontitis in Medalists was only 13.5% which was lower than reported levels in diabetic patients of similar ages. Periodontal parameters, including bleeding on probing, plaque index, gingival index, and demographic traits, including male sex, chronological age, and age at diagnosis were significantly associated with severity of periodontitis, which did not associate with diabetes duration, hemoglobin A1c (HbA1c), body mass index, and lipid profiles. Random serum C-peptide levels inversely associated with severity of periodontitis (P = 0.03), lower probing depth (P = 0.0002), and clinical attachment loss (P = 0.03). Prevalence of cardiovascular diseases (CVD) and systemic inflammatory markers, plasma interleukin-6 (IL-6), and serum immunoglobulin G titer against Porphyromonas gingivalis positively associated with severity of periodontitis (P = 0.002 and 0.02, respectively). Antibody titer to P. gingivalis correlated positively and significantly with CVD, serum IL-6, and high-sensitivity C-reactive protein.

CONCLUSIONS

Some Medalists could be protected from severe periodontitis even with hyperglycemia. Endogenous protective factors for periodontitis could possibly be related to residual insulin production and lower levels of chronic inflammation.

Non-oral gram-negative facultative rods in chronic periodontitis microbiota

OBJECTIVE

The subgingival prevalence of gram-negative facultative rods not usually inhabiting or indigenous to the oral cavity (non-oral GNFR), as well as selected periodontal bacterial pathogens, were evaluated by culture in untreated and treated chronic periodontitis patients.

METHODS

Subgingival biofilm specimens from 102 untreated and 101 recently treated adults with chronic periodontitis in the Netherlands were plated onto MacConkey III and Dentaid selective media with air-5% CO2 incubation for isolation of non-oral GNFR, and onto enriched Oxoid blood agar with anaerobic incubation for recovery of selected periodontal bacterial pathogens. Suspected non-oral GNFR clinical isolates were identified to a species level with the VITEK 2 automated system.

RESULTS

A total of 87 (42.9%) out of 203 patients yielded subgingival non-oral GNFR. Patients recently treated with periodontal mechanical debridement therapy demonstrated a greater prevalence of non-oral GNFR (57.4% vs 28.4%, P < 0.0001), and a greater number of different non-oral GNFR species (23 vs 14 different species), than untreated patients. Sphingomonas paucimobilis was the most frequently isolated subgingival non-oral GNFR species. Several GNFR species normally found in animals and human zoonotic infections, and not previously detected in human subgingival biofilms, were recovered from some patients, including Bordetella bronchispetica, Pasteurella canis, Pasteurella pneumotropica and Neisseria zoodegmatis. Porphyromonas gingivalis and Tannerella forsythia were significantly associated with the presence of subgingival non-oral GNFR.

CONCLUSIONS

A surprisingly high proportion of Dutch chronic periodontitis patients yielded cultivable non-oral GNFR in periodontal pockets, particularly among those recently treated with periodontal mechanical debridement therapy. Since non-oral GNFR species may resist mechanical debridement from periodontal pockets, and are often not susceptible to many antibiotics frequently used in periodontal practice, their subgingival presence may complicate periodontal treatment in species-positive patients and increase risk of potentially dangerous GNFR infections developing at other body sites.

Antibiotic susceptibility of periodontal Streptococcus constellatus and Streptococcus intermedius clinical isolates

BACKGROUND

Streptococcus constellatus and Streptococcus intermedius in subgingival dental plaque biofilms may contribute to forms of periodontitis that resist treatment with conventional mechanical root debridement/surgical procedures and may additionally participate in some extraoral infections. Because systemic antibiotics are often used in these clinical situations, and little is known of the antibiotic susceptibility of subgingival isolates of these two bacterial species, this study determined the in vitro susceptibility to six antibiotics of fresh S. constellatus and S. intermedius clinical isolates from human periodontitis lesions.

METHODS

A total of 33 S. constellatus and 17 S. intermedius subgingival strains, each recovered from separate patients with severe chronic periodontitis (n = 50) before treatment, were subjected to antibiotic gradient strip susceptibility testing with amoxicillin, azithromycin, clindamycin, ciprofloxacin, and doxycycline on blood-supplemented Mueller-Hinton agar and to the inhibitory effects of metronidazole at 16 mg/L in an enriched Brucella blood agar dilution assay. Clinical and Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing interpretative standards were used to assess the results.

RESULTS

Clindamycin was the most active antibiotic against S. constellatus (minimum inhibitory concentration at 90% [MIC90] 0.25 mg/L), and amoxicillin was most active against S. intermedius (MIC90 0.125 mg/L). A total of 30% of the S. constellatus and S. intermedius clinical isolates were resistant in vitro to doxycycline, 98% were only intermediate in susceptibility to ciprofloxacin, and 90% were resistant to metronidazole at 16 mg/L.

CONCLUSION

Subgingival S. constellatus and S. intermedius exhibited variable antibiotic susceptibility profiles, potentially complicating empirical selection of periodontitis antibiotic therapy in patients who are species positive.

Results from the Periodontitis and Vascular Events (PAVE) Study: a pilot multicentered, randomized, controlled trial to study effects of periodontal therapy in a secondary prevention model of cardiovascular disease

BACKGROUND

In the Periodontitis and Vascular Events (PAVE) pilot study, periodontal therapy was provided as an intervention in a secondary cardiac event prevention model through five coordinated cardiac-dental centers.

METHODS

Subjects were randomized to either community care or protocol provided scaling and root planing to evaluate effects on periodontal status and systemic levels of high-sensitivity C-reactive protein (hs-CRP).

RESULTS

After 6 months, there was a significant reduction in mean probing depth and extent of 4- or 5-mm pockets. However, there were no significant differences in attachment levels, bleeding upon probing, or extent of subgingival calculus comparing subjects assigned to protocol therapy (n = 151) to those assigned to community care (n = 152). Using intent-to-treat analyses, there was no significant effect on serum hs-CRP levels at 6 months. However, 48% of the subjects randomized to community care received preventive or periodontal treatments. Secondary analyses demonstrated that consideration of any preventive or periodontal care (i.e., any treatment) compared to no treatment showed a significant reduction in the percentage of people with elevated hs-CRP (values >3 mg/l) at 6 months. However, obesity nullified the periodontal treatment effects on hs-CRP reduction. The adjusted odds ratio for hs-CRP levels >3 mg/l at 6 months for any treatment versus no treatment among non-obese individuals was 0.26 (95% confidence interval: 0.09 to 0.72), adjusting for smoking, marital status, and gender.

CONCLUSION

This pilot study demonstrated the critical role of considering obesity as well as rigorous preventive and periodontal care in trials designed to reduce cardiovascular risk.

Use of Preexisting Radiographs for Assessing Periodontal Disease in Epidemiologic Studies

OBJECTIVES

This study evaluates the feasibility of obtaining preexisting dental radiographs by mail, the validity of assessing alveolar bone loss from posterior radiographs compared to full mouth, and the validity of alveolar bone loss assessed from radiographs taken at different times.

METHODS

This investigation uses data obtained for a study evaluating associations between oral conditions, blood biomarkers, and coronary heart disease within two large cohorts: the Nurses' Health Study and the Health Professionals Follow-up Study. If consenting participants had dental radiographs, we requested these radiographs from their dentists. Some dentists returned multiple sets of radiographs, which enabled us to conduct this study. A calibrated periodontist read all radiographs with good intraexaminer reliability (r=0.91). We compared posterior radiographs to full mouth (n=121 sets), as well as radiographs taken at different times (mean difference of 5 years) (n=102 pairs).

RESULTS

Of the 812 participants, 81 percent consented and 66 percent provided radiographs. Posterior radiographs underestimated periodontitis (> or =1 site with > or =5 mm alveolar bone loss) prevalence by 6 percent (53.7% vs 57.0%) compared to full mouth, with sensitivity of 0.94 (95% confidence interval [CI]=0.86, 0.98) and specificity of 1. Spearman correlation coefficients comparing mean alveolar bone loss were 0.70 for anterior versus posterior teeth (mean difference=0.48), 0.92 for posterior teeth versus full mouth (mean difference=0.25), and 0.78 for pairs of radiographs taken at different times (mean difference=0.01). The kappa statistic was 0.70 comparing radiographs taken within 5 years and 0.29 when the period extended beyond 5 years.

CONCLUSION

Preexisting radiographs are feasible for use in epidemiologic studies and provide valid assessments of periodontal disease.

Risk factors for periodontitis

This review presents a selected overview of the literature concerning risk factors for periodontitis. That in some individuals gingivitis develops into periodontitis is still a matter of extensive research. Cross-sectional studies of clinical and microbiological factors can be meaningful. Longitudinal studies of the natural history allow analysis of potential factors and conditions that may have an impact on the disease process. At present, several possible risk factors for the initiation and progression of periodontitis have been identified: age, gender, plaque, calculus, existing attachment loss. A consistent finding appears to be genetic predisposition for the development of the disease. In terms of microbiology, several micro-organisms have been identified. The results of the Java Project on natural development of Periodontal Disease clearly pinpoint Actinobacillus actinimycetemcomitans as being associated with the onset of disease. The presence of subgingival calculus was found to be associated with onset and dental plaque with progression of disease. Consistent with literature males are more susceptible to disease. The presence of pockets > or = 5 mm appear to be a useful tool, since it was found to be a prognostic factor for disease progression.

Association of Fcgamma receptor IIa genotype with chronic periodontitis in Caucasians

BACKGROUND

Functional polymorphisms of immunoglobulin G (IgG) Fc receptors IIIa and IIIb (FcgammaRIIIa and FcgammaRIIIb) have been shown as risk factors for periodontitis. The aim of this study is to examine whether FcgammaRIIa polymorphism is associated with a disease risk as well.

METHODS

Baseline periodontal and general health examinations were carried out on 1,221 Caucasian adults. From these, 422 subjects with moderate to severe, or little or no periodontal disease were assigned to two groups according to their mean clinical attachment loss (CAL). Subjects with mean CAL > or = 2.94 mm were diagnosed with chronic periodontitis (n = 213, 62 never-smokers and 151 smokers). Subjects with mean CAL < or = 1.77 mm were considered as having little or no periodontal disease and designated as controls (n = 209, 125 never-smokers and 84 smokers). The FcgammaRIIa genotype for three bi-allelic polymorphisms (FcgammaRIIa-R/ R131, R/H131, and H/H131) was determined by means of allele-specific polymerase chain reactions.

RESULTS

The distribution of FcgammaRIIa genotype between the patient and control groups was significantly different, with enrichment of the high ligand-binding genotype FcgammaRIIa-H/H131 in the patients (patients versus controls: 36.6% versus 25.4%; P = 0.04). Multivariate logistic regression model demonstrated that subject age and gender, smoking, and the FcgammaRIIa genotype were significantly associated with severity of chronic periodontitis. For smokers, a significant over-representation of FcgammaRIIa-H/H131 in the patient group compared to the control group (patients versus controls: 35.1% versus 19.0%; P = 0.03). Additionally, smokers with FcgammaRIIa-H/H131 exhibited significantly greater mean CAL (mean +/- SE: 3.44 +/- 0.16 mm) than those with FcgammaRIIa-R/H131 (2.91 +/- 0.14 mm) and R/R131 (2.82 +/- 0.16 mm) (P = 0.04). There was no association between FcgammaRIIa genotype and the disease susceptibility or severity in subjects who had never smoked.

CONCLUSIONS

Our results suggest that the FcgammaRIIa-H/H131 genotype may be associated with chronic periodontitis risk (and disease severity) in Caucasian smokers. Further studies with families and studies of mechanisms are necessary to help establish the extent to which this is a genetic determinant of periodontal diseases.

The usefulness of using Ramfjord teeth in predicting periodontal status of a Tanzanian adult population

OBJECTIVES

The only partial mouth index that has been validated against full-mouth examinations in the East African population is the CPITN (Community Periodontal Index of Treatment Needs). Since the Ramfjord index can potentially shorten the examination time by almost half, we evaluated Ramfjord teeth in predicting full-mouth periodontal status of an adult population in Tanzania.

MATERIAL AND METHODS

Pocket depth was measured for 192 consecutive patients aged from 15 to 77 years (36 years old on average); 86 (45%) females referred to the Department of Restorative Dentistry, Muhimbili National Hospital, Tanzania between January 1997 and December 1999, and the mean pocket depth for full-mouth and Ramfjord teeth was calculated.

RESULTS

The correlation between the mean pocket depth calculated from the full-mouth and Ramfjord teeth was 0.96. The beta coefficient for the mean pocket depth measured by Ramfjord teeth to predict the full-mouth mean was 0.94, and was not affected by adjustment for age, missing teeth or sex.

CONCLUSION

This overall high agreement between Ramjford teeth and full-mouth periodontal pocket situation confirms the epidemiological validity of Ramfjord's dental sample in our setting.

Alcohol consumption increases periodontitis risk

Alcohol consumption impairs neutrophil, macrophage, and T-cell functions, increasing the likelihood of infections. We examined the association between alcohol consumption and periodontitis, prospectively, among 39,461 male health professionals aged 40 to 75 years and free of periodontitis at the start of follow-up. Alcohol intake was assessed at baseline and updated every 4 years by a food-frequency questionnaire. Periodontal disease status was self-reported and validated against radiographs. Multivariate analysis was adjusted for age, smoking, diabetes, body-mass index, physical activity, time period, and caloric intake. During 406,160 person-years of follow-up, there were 2125 cases of periodontitis. Compared with non-drinkers, the relative risk (95% confidence interval) among men reporting usual alcohol intake of 0.1-4.9 g/day was 1.24 (1.09, 1.42); 5.0 to 14.9 g/day, 1.18 (1.04, 1.35); 15 to 29.9 g/day, 1.18 (1.01, 1.38); and > 30 g/day, 1.27 (1.08, 1.49). The results suggest that alcohol consumption is an independent modifiable risk factor for periodontitis.

Multivariate analysis of oral hygiene data from a representative sample

BACKGROUND

This analysis was based on an oral health survey with dental examination and interview by questionnaire.

METHOD

The data set comprised a representative random sample of the over 14-year-old residents of the German Federal State of Saxony (n=714), in which a multivariate logistic regression analysis was conducted. The dependent variable was the debris index (DI) score of the oral hygiene index scoring system. The subjects were split into 2 groups by dividing DI scores into tertiles: those with acceptable oral hygiene (1st tertile, DI 0.00< or =1.20) and unacceptable oral hygiene (2nd and 3rd tertile, DI>1.20). The most important explanatory variable was the community periodontal index of treatment need (CPITN).

RESULTS

The higher the CPITN score, the lower the probability of acceptable oral hygiene. In relation to the reference category score 0, higher CPITN scores were associated with acceptable oral hygiene, with an odds ratio 0.05 (95% confidence interval (CI)=0.01-0.23) for CPITN score 1, and an odds ratio 0.02 (95% CI: 0.01-0.08) for score 4. Further significant variables were: self-evaluation of tooth condition, gender, and the number of missing teeth.

In vitro evaluation of the retention of three species of pathogenic microorganisms by three different types of toothbrush

The retention and survival of microorganisms on toothbrushes pose a threat of recontamination for certain patients at risk. In order to measure the influence of brush design and optimize the choice of toothbrush model for complementary studies, the in vitro retention of three microbial species (Porphyromonas gingivalis ATCC 33277, Streptococcus mutans ATCC 25175 and Candida albicans ATCC 26555) was evaluated for three types of toothbrush. Two series of standardized experiments were carried out for each brush and microorganism. The first series tested the retention of the microorganisms on the head portion of the brush, while the second measured retention on the head of the brush and the part of the handle inserted in the mouth during brushing. For each series, the microorganisms were counted at T0 and T24 (after storage of the brushes at room temperature for 24 h). Depending on the microorganism studied, from 0.2% to 2% of the initial inoculum was retained on the brush. The number detected increased with the size of the exposed area. After 24 h, P. gingivalis and S. mutans were found on only one type of brush. C. albicans survived on all three. These results confirm that microorganisms can quickly colonize toothbrushes.

Localized adhesion molecule expression and circulating LFA-3 levels in adult and early onset forms of periodontitis

Because of their importance in mediating cellular interactions in chronic inflammatory diseases, this study has examined the expression of a number of adhesion molecules in adult (n=11), generalized early onset (n=5) and localized early onset (n=2) forms of periodontitis. In comparison with immunostaining profiles of cryostat sections of healthy gingival tissue (n=7), the beta 1 integrins VLA-1, VLA-2 and VLA-4 were found to be up-regulated in periodontitis, with VLA-6 being markedly elevated. Although only small differences were observed in ICAM-1 and LFA-3 expression in the gingival epithelium, there was particularly notable up-regulation of these adhesion molecules within the inflammatory infiltrates of the diseased tissues. However, there were no statistically significant differences between the serum levels of a soluble form of LFA-3 in periodontitis patients (n=47) compared with healthy control subjects (n=40), although the generalized early onset and adult periodontitis groups exhibited wider ranges of circulating LFA-3. These findings show that there is localized modulation of adhesion molecule expression in the chronic inflammatory periodontal diseases studied, but that the levels of LFA-3 in the circulation nevertheless remain unaffected.

Risk of severe periodontal disease in a Swedish adult population. A cross-sectional study

In this study, potential risk factors for severe periodontal disease were identified in a cross-sectional sample from the county of Jonkoping, Sweden. 547 adults 20-70 years of age were categorised clinically and radiographically by level of periodontal disease experience. These levels were used to divide the sample into groups--individuals without any reduction in periodontal bone level (60%) and those with severe periodontal bone loss (13%)--which were then used in univariate and multivariate logistic regression analyses as dependent variable. Demographic, socio-economic, general health, smoking habits, clinical, and dental care variables were used in the different regression analyses. In the univariate model, age (20-70 years) was found to be correlated with more severe periodontal disease experience (odds ratio: 1.13; 95% CI: 1.10-1.17). The association with periodontal disease was more pronounced for the older age groups (50, 60, and 70 years). A negative financial situation was also related to severe periodontal bone loss when regressed univariately (odds ratio 2.20 [95%: 1.04-4.68]). Moderate-heavy smoking (> or =10 cigarettes/day) appeared to be associated with severe periodontal destruction with an odds ratio of 9.78 (95% CI: 3.62-36.42). Of the clinical variables in the univariate model, higher mean levels of supragingival dental plaque and the presence of subgingival calculus were related to more severe periodontal disease with odds ratios of 1.02 (95%: 1.01-1.03) and 2.96 (95%: 1.50-5.88), respectively. When the same variables were regressed multivariately, age (continuous) (odds ratio 1.17 [95% CI: 1.12-1.22]), moderate-heavy smoking (odds ratio 11.84 [95% CI: 4.19-33.50]), and higher mean levels of plaque (odds ratio 1.02 [95% CI: 1.00-1.03]) remained significant. Light smoking (1-9 cigarettes/day) was not significantly associated with severe periodontal disease in the 2 regression models. The present study demonstrated that smoking, greater age, and higher mean levels of plaque are potential risk factors for severe periodontal disease in this specific population.

Periodontitis-associated marker bacteria in an urban North American patient population: application of a commercial immunoassay

We used an immunoassay to demonstrate marker organisms (Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans) in 3 private practice populations (F-ME periodontist, 55 patients; MHM periodontist, 179 patients; and EWM general dentist, 19 patients). Occurrence of the marker organisms involves the whole oral environment, not just individual sites, as shown by close correlation between presence of the marker organisms in 2 independent sites/samples within a single mouth. Presence of the marker P. gingivalis (and P. intermedia) relates closely to periodontal pocketing while presence of A. actinomycetemcomitans does not have this pocket-associated characteristic. There was no significant relationship between presence of the marker organisms and the number of teeth in a mouth, and in the periodontal practice patients there was no significant effect of gender on occurrence of the marker organisms. A. actinomycetemcomitans and the other 2 markers were found over the entire age range (12 to 75) of our patients. Regular periodontal treatment reduced occurrence of all marker organisms and increased the frequency of marker-negative patients and sites. Occurrence of the marker organisms above immunoassay threshold levels appears to represent how receptive a patient is to each individual organism. Most patients appear receptive to the presence of P. intermedia whether treated or not. Significantly fewer patients who underwent regular treatment show the presence of P. gingivalis or A. actinomycetemcomitans when compared to untreated patients. Diagnostic application of microbial markers requires ongoing clinical assessment of patients and careful clinical judgment. 1391.

Imaging of hard- and soft-tissue structure in the oral cavity by optical coherence tomography

We have developed a prototype optical coherence tomography (OCT) system for the imaging of hard and soft tissue in the oral cavity. High-resolution images of in vitro porcine periodontal tissues have been obtained with this system. The images clearly show the enamel-cementum and the gingiva-tooth interfaces, indicating OCT is a potentially useful technique for diagnosis of periodontal diseases. To our knowledge, this is the first application of OCT for imaging biologic hard tissue.

Practical periodontal screening and diagnosis

The differences in approach between screening for and diagnosis of periodontal diseases are highlighted. The Periodontal Screening and Recording procedure is discussed in terms of its evolution and current application. For patients screened and found to have more advanced periodontal problems a panoramic dental radiograph with restricted supplemented periapicals are recommended. A comprehensive clinical periodontal examination should be performed for these patients, but it is argued that this may be performed after the initial hygiene phase of treatment. In establishing a diagnosis it is suggested that attention be paid to possible risk exposures. Newer, non-anatomic diagnostic procedures are discussed in principle and it is concluded that these do not have a practical application at present.

Radiographic periodontal findings in an elderly Finnish population

By means of panoramic radiography and additional intraoral radiographs, the occurrence of calculus, the extent of horizontal bone loss, the depth and number of infrabony pockets, the number of furcation lesions, and the number of interproximal restoration overhangs were studied in 169 dentate 76-, 81-, and 86-year-old subjects (54 male and 115 females) living at home. Alveolar bone loss (horizontal or vertical) among the participants was common, and in only 8 subjects (5%) was it judged non-existent. It was slight in 30 subjects (18%), moderate in 53 (31%), and advanced in 78 (46%). Infrabony pockets were found in 51% of the subjects and furcation lesions in 28%. The presence of calculus did not correlate with the other parameters. The number of interproximal overhangs was associated with the number of infrabony pockets and of furcation lesions (R=0.3, p<0.001 and p<0.0001) and the number of infrabony pockets with the number of furcation lesions (R=0.4, p<0.0001). Our study shows that periodontal findings are common in the dentate elderly, and associations recently found between periodontal infections and several serious diseases make radiographic examination an integral part of the oral examination of the elderly patient.

Periodontitis detection efficacy of film and digital images

OBJECTIVE

The objective of this study was to evaluate the accuracy of alveolar crestal bone detection in a comparison of unenhanced and enhanced Sidexis (Siemens Medical Systems, Inc., Bensheim, Germany) digital images with Ektaspeed Plus (Eastman Kodak, Rochester, N.Y.) films by means of receiver operating characteristic analysis.

STUDY DESIGN

More than 100 proximal and furcal areas in the anterior and posterior areas of the mandible and maxilla of each of three tissue-equivalent human skull phantoms were imaged with film, direct digital images, and contrast- and brightness-enhanced digital images. Alveolar crest status was assessed by a consensus panel of three experts who used the Delphi method and evaluated information from all of the imaging modalities concurrently. Five observers assessed all images for the presence or absence of crestal bone loss using a five-point confidence scale. Receiver operating characteristic curves were generated, and calculated areas (Az) were analyzed by means of analysis of variance.

RESULTS

The expert panel determined that of 106 crestal areas, 48 were disease free and 58 exhibited bone loss greater than 2 mm apical to the cemento-enamel junction. Analysis of variance of observer Az scores showed significant differences among readers (p < 0.001) and among readings (p = 0.027), but not among modalities (p = 0.435). Mean Az values for the different modalities were as follows: Sidexis, 0.70; enhanced Sidexis, 0.71; Ektaspeed Plus films, 0.735.

CONCLUSION

The Sidexis digital imaging system was not significantly different from Ektaspeed Plus film for crestal bone evaluation in this in vitro study.

Microbiota of health, gingivitis, and initial periodontitis

This study compared the subgingival microbiota in periodontal health, gingivitis and initial periodontitis using predominant culture and a DNA probe, checkerboard hybridization method. 56 healthy adult subjects with minimal periodontal attachment loss were clinically monitored at 3-month intervals for 12 months. More sites demonstrated small increments of attachment loss than attachment gain over the monitoring period. Sites, from 17 subjects, showing > or = 1.5 mm periodontal attachment loss during monitoring were sampled as active lesions for microbial analysis. Twelve subjects demonstrated interproximal lesions, and 5 subjects had attachment loss at buccal sites (recession). Cultural studies identified Bacteroides forsythus, Campylobacter rectus, and Selenomonas noxia as the predominant species associated with active interproximal lesions (9 subjects), whereas Actinomyces naeslundii, and Streptococcus oralis, were the dominant species colonizing buccal active sites. A. naeslundii, Campylobacter gracilis, and B. forsythus (at lower levels than active sites) were the dominant species cultured from gingivitis (10 subjects). Health-associated species (10 subjects) included Streptococcus oralis, A. naeslundii, and Actinomyces gerencseriae. DNA probe data identified higher mean levels of B. forsythus and C. rectus with active (7 subjects) compared to inactive periodontitis sites. Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans were detected infrequently. Cluster analysis of the cultural microbiota grouped 8/9 active interproximal lesions in one subcluster characterized by a mostly gram-negative microbiota, including B. forsythus and C. rectus. The data suggest that B. forsythus C. rectus and S. noxia were major species characterizing sites converting from periodontal health to disease. The differences in location and microbiota of interproximal and buccal active sites suggested that different mechanisms may be involved in increased attachment loss.

Dental calculus: recent insights into occurrence, formation, prevention, removal and oral health effects of supragingival and subgingival deposits

Dental calculus, both supra- and subgingival occurs in the majority of adults worldwide. Dental calculus is calcified dental plaque, composed primarily of calcium phosphate mineral salts deposited between and within remnants of formerly viable microorganisms. A viable dental plaque covers mineralized calculus deposits. Levels of calculus and location of formation are population specific and are affected by oral hygiene habits, access to professional care, diet, age, ethnic origin, time since last dental cleaning, systemic disease and the use of prescription medications. In populations that practice regular oral hygiene and with access to regular professional care, supragingival dental calculus formation is restricted to tooth surfaces adjacent to the salivary ducts. Levels of supragingival calculus in these populations is minor and the calculus has little if any impact on oral-health. Subgingival calculus formation in these populations occurs coincident with periodontal disease (although the calculus itself appears to have little impact on attachment loss), the latter being correlated with dental plaque. In populations that do not practice regular hygiene and that do not have access to professional care, supragingival calculus occurs throughout the dentition and the extent of calculus formation can be extreme. In these populations, supragingival calculus is associated with the promotion of gingival recession. Subgingival calculus, in "low hygiene" populations, is extensive and is directly correlated with enhanced periodontal attachment loss. Despite extensive research, a complete understanding of the etiologic significance of subgingival calculus to periodontal disease remains elusive, due to inability to clearly differentiate effects of calculus versus "plaque on calculus". As a result, we are not entirely sure whether subgingival calculus is the cause or result of periodontal inflammation. Research suggests that subgingival calculus, at a minimum, may expand the radius of plaque induced periodontal injury. Removal of subgingival plaque and calculus remains the cornerstone of periodontal therapy. Calculus formation is the result of petrification of dental plaque biofilm, with mineral ions provided by bathing saliva or crevicular fluids. Supragingival calculus formation can be controlled by chemical mineralization inhibitors, applied in toothpastes or mouthrinses. These agents act to delay plaque calcification, keeping deposits in an amorphous non-hardened state to facilitate removal with regular hygiene. Clinical efficacy for these agents is typically assessed as the reduction in tartar area coverage on the teeth between dental cleaning. Research shows that topically applied mineralization inhibitors can also influence adhesion and hardness of calculus deposits on the tooth surface, facilitating removal. Future research in calculus may include the development of improved supragingival tartar control formulations, the development of treatments for the prevention of subgingival calculus formation, the development of improved methods for root detoxification and debridement and the development and application of sensitive diagnostic methods to assess subgingival debridement efficacy.

Therapy-resistant periodontitis (I). Clinical and treatment characteristics

The aim of this study was to evaluate the clinical criteria for classification of 2 different patient groups. From retrospective comparisons of pocket probing depth (PPD) charts, we classified 22 patients as either non-responding or responding to periodontal treatment. The non-responding patient group, in comparison with the responding patient group, showed a profile over time of less PPD reduction in response to periodontal treatment. Information registered in each patient's file regarding clinical periodontal conditions, as well as treatment procedure characteristics, was gathered. Bivariate analyses were performed. 3 clinical variables (frequency of mean PPD > or = 6 mm during the treatment period; at final registration; and the mobility score at the final registration) indicated that 2 separate patient groups had been identified. Although the patient groups exhibited advanced periodontitis at the beginning of treatment, both groups at the end of treatment had lost very few (1-2) teeth, probably as a result of regular supportive treatment. The characteristics of the selected clinical criteria warrant the use of these 2 patient groups in further analysis of the relation of psychosocial stress and microbiological characteristics of therapy-resistant periodontitis.

Changes in periodontal treatment needs. A follow-up study of Oslo citizens from the ages of 35 to 50 years

A random sample of 35-year-old subjects from Oslo took part in a dental survey in 1973 and were re-examined in 1988. Eighty-one subjects (85%) attended the final examination. The need for periodontal treatment was assessed by the Periodontal Treatment Need System (PTNS), and the oral hygiene by the Simplified Oral Hygiene Index (OHI-S). The participants attended a structured interview and answered a questionnaire about general and dental health habits as well as psycho-social factors. Only small changes in the distribution of subjects in the different PTNS categories were found to have taken place during the 15 years. In 1973, 56.8% were in need of scaling (Class B) and 32.1% had one or more deep inflamed pockets (Class C), and in 1988 the scores were 54.3% and 30.1% respectively. A logistic regression model was used to study the associations between risk factors and increased treatment need, as expressed by increase in the number of C-quadrants. Increased number of C-quadrants was positively associated both with short duration of education and with no interdental cleaning. Using a socio-ecological model for periodontal diseases, variables describing the items "behaviour" and "environment" were found to be most closely associated with increased need for periodontal treatment.

Histological location of a standardized periodontal probe in man

The purpose of this study was to locate the position of the periodontal probe tip using a pressure of 126 N/cm2 (force of 0.30N using a round periodontal probe tip with a diameter of 0.55 mm). The influence of gingival inflammation on this position was also studied. Subjects with three levels of periodontal health and disease were entered into the study and each contributed one experimental tooth. At each site a standardized probing system was used to place a probe into a clinical pocket. The probe tip was luted to the test tooth surface. The tooth with its gingival tissue and probe tip was extracted, fixed, and processed for histological measurements. Distances in mm were obtained from the cemento-enamel junction (CEJ) to the probe tip, to the base of the crevice/pocket, and to the most coronal connective tissue attachment. Analysis of the data indicated that clinical inflammation was not a factor in the placement of the probe tip at crevice/pocket's landmarks relative to the CEJ; however variability of probing may have caused the non-significance. The probing system placed the probe tip 0.66 mm apical to the base of the crevice/pocket and 0.06 mm coronal to the most coronal connective tissue attachment. These conclusions corroborated the results of the previous study in dogs which predicted probe placement of 0.44 mm apical to the base of the crevice using the standardized pressure of this probing system.

Maintenance therapy in young adults with severe generalized periodontitis

The purpose of this study was to evaluate one year of maintenance therapy in young adults with severe periodontitis (SP) who had previously received periodontal therapy consisting of root planing and scaling followed by open flap debridement. Subjects were evaluated with clinical and microbiological measurements at 3, 6, 9, and 12 months following the completion of active therapy. Subjects were included in the study if they completed a minimum of two evaluation appointments. Monitoring of these subjects during the maintenance phase was analyzed by three methods. First, changes in mean attachment level and mean probing depth were calculated at 3-month intervals to determine if the subjects continued to lose or gain attachment and/or had periodontal pockets of increasing or decreasing depth. Second, the frequency of periodontal breakdown was determined and compared to breakdown rates of subjects in other patient populations. Third, future changes in attachment level were related to the presence or absence of two putative periodontal pathogens, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in subgingival plaque. Mean attachment level remained constant in 13 subjects who completed one year of maintenance therapy. However, mean probing depth increased at a yearly rate of 0.19 mm and in periodontally-involved sites pocket depth increased at a yearly rate of 0.65 mm both of which were statistically significantly different from 0 (P < .05). The frequency of periodontal breakdown in this study was higher than reported in other similar studies of different periodontitis patient populations. The remainder of the data in the study was from 21 subjects who had completed at least two recall appointments.(ABSTRACT TRUNCATED AT 250 WORDS)