Intra-oral pattern of tooth and periodontal bone loss between the age of 50 and 60 years. A longitudinal prospective study

Oral Health Status at Age 60 and 72 Years-A Longitudinal Study

OBJECTIVE

This study investigated oral health status in 60-year-old individuals over 12 years.

MATERIALS AND METHODS

Data were obtained from The Swedish National Study on Aging and Care (SNAC). One hundred nineteen 60-year-old individuals (48% females) underwent a clinical and radiographic baseline examination (2001-2003) and follow-up examination in 2013-2015. For statistical analyses, paired t-tests and McNemar's test were performed. Statistical significance was determined at p < 0.05.

RESULTS

At the 12-year follow-up, the mean number of teeth and the proportion of individuals having ≥ 20 teeth decreased (p < 0.001). The mean number of teeth with buccal/lingual and approximal caries lesions increased (p < 0.029 and p < 0.031). Individuals with a distance from the cement-enamel junction to the bone of ≥ 5 mm increased in total (p < 0.002) and in males (p < 0.006). The prevalence of gingivitis increased in total (p < 0.001). The prevalence of periodontitis showed a significant increase in total (p < 0.043) and in females (p < 0.039).

CONCLUSION

The present study indicates that oral health status in 60-year-old individuals deteriorates over 12 years. However, the deteriorations were minor in terms of tooth loss, caries lesions, and changes in periodontal status.

A Tale of Two Fimbriae: How Invasion of Dendritic Cells by Porphyromonas gingivalis Disrupts DC Maturation and Depolarizes the T-Cell-Mediated Immune Response

Porphyromonas gingivalis (P. gingivalis) is a unique pathogen implicated in severe forms of periodontitis (PD), a disease that affects around 50% of the US population. P. gingivalis is equipped with a plethora of virulence factors that it uses to exploit its environment and survive. These include distinct fimbrial adhesins that enable it to bind to other microbes, colonize inflamed tissues, acquire nutrients, and invade cells of the stroma and immune system. Most notable for this review is its ability to invade dendritic cells (DCs), which bridge the innate and adaptive immune systems. This invasion process is tightly linked to the bridging functions of resultant DCs, in that it can disable (or stimulate) the maturation function of DCs and cytokines that are secreted. Maturation molecules (e.g., MHCII, CD80/CD86, CD40) and inflammatory cytokines (e.g., IL-1b, TNFa, IL-6) are essential signals for antigen presentation and for proliferation of effector T-cells such as Th17 cells. In this regard, the ability of P. gingivalis to coordinately regulate its expression of major (fimA) and minor (mfa-1) fimbriae under different environmental influences becomes highly relevant. This review will, therefore, focus on the immunoregulatory role of P. gingivalis fimbriae in the invasion of DCs, intracellular signaling, and functional outcomes such as alveolar bone loss and immune senescence.

Rural-urban differences in oral health among older people in Southern Brazil

This study aimed to assess the association between oral health and rurality in an older Brazilian population. Population-based samples of 1,451 urban and 411 rural elders were obtained from two databases. Several oral health and related measures, including the number of teeth lost, use of dental prostheses, dental visits, self-reported oral health, and perceived need for a dental prosthesis, were compared. Oral health-related information was obtained by a trained research team with interviews conducted in the individuals' homes. Regression models were used to verify the association between living in rural areas and oral health outcomes after adjusting for possible confounding factors. The elderly population mostly comprised of women in rural or urban areas, and the mean age was 70 years in both locations. Less-educated individuals (without or with complete elementary schooling) were more common in rural regions than in urban areas. After adjustment for socioeconomic characteristics, living in rural areas was associated with a lower perceived need for dental prostheses (PR 0.68, 95% CI 0.56-0.84), poor self-reported oral health (OR 1.24; 95% CI 1.05-1.46), and having fewer teeth (β -1.31; 95% CI -2.18 to -0.45). The place of residence had a significant impact on oral health indicators, with rurality negatively influencing oral health. These findings suggest that preventive and curative strategies for dental services may be needed for the Brazilian rural population.

Normative and subjective need for dental prosthesis: accuracy and agreement in a population based-study

The aim of our study was to compare normative need for dental prosthesis (estimated by dentists) with subjective need (self-reported) by testing the accuracy and agreement and comparing direction and magnitude of associations with independent variables using both as outcomes. A representative sample of a birth cohort study (n = 900) was assessed at 31 years of age. Subjective need was obtained from questionnaire. Both normative and subjective need variables were dichotomized in (a) individuals with need for dental prosthesis and (b) without need for dental prosthesis. Accuracy was assessed by sensitivity (SE), specificity (SP), positive (PPV) and negative (NPV) predictive values. Agreement of normative and subjective need was assessed estimating kappa index. Sex, income, educational level, use of dental services and self-reported oral health were used to compare the associations with normative and subjective need. Prevalence of normative need was 48.9% and subjective need was 34.9%. Agreement (kappa: 0.43) and accuracy between normative and subjective need for dental prosthesis was low (SE: 56.5, 95%CI: 50.3-62.6; SP: 85.8, 95%CI: 81.1-89.7; PPV: 79.1, 95%CI: 72.6-84.7; NPV: 67.3, 95%CI: 62.1-72.2). When considering individuals with loss in anterior teeth, results showed a good agreement (kappa: 0.82) and accuracy between normative and subjective need (SE: 93.3, 95%CI: 68.1-99.8; SP: 88.9, 95%CI: 51.8-99.7; PPV: 93.3, 95%CI: 68.1-99.8; NPV: 88.9, 95%CI: 51.8-99.7). Direction and magnitude of associations with normative and subjective need were similar. Thus, normative need for dental prosthesis differs from subjective need in adults, except when anterior losses are present.

Contemporary approaches for identifying individual risk for periodontitis

Key breakthroughs in our understanding of the etiology and principles of predictable treatment of patients with chronic periodontitis first emerged in the late 1960s and carried on into the mid-1980s. Unfortunately, some generalizations of the evidence led many to believe that periodontitis was a predictable result of exposure to bacterial plaque accumulations over time. For a brief period, the initial plaque concept was translated by some to implicate specific bacterial infections, with both concepts (plaque exposure and specific infection) being false assumptions that led to clinical outcomes which were frustrating to both the clinician and the patient. The primary misconceptions were that every individual was equally susceptible to periodontitis, that disease severity was a simple function of magnitude of bacterial exposure over time, and that all patients would respond predictably if treated based on the key principles of bacterial reduction and regular maintenance care. We now know that although bacteria are an essential initiating factor, the clinical severity of periodontitis is a complex multifactorial host response to the microbial challenge. The complexity comes from the permutations of different factors that may interact to alter a single individual's host response to challenge, inflammation resolution and repair, and overall outcome to therapy. Fortunately, although there are many permutations that may influence host response and repair, the pathophysiology of chronic periodontitis is generally limited to mild periodontitis with isolated moderate disease in most individuals. However, approximately 20%-25% of individuals will develop generalized severe periodontitis and probably require more intensive bacterial reduction and different approaches to host modulation of the inflammatory outcomes. This latter group may also have serious systemic implications of their periodontitis. The time appears to be appropriate to use what we know and currently understand to change our approach to clinical care. Our goal would be to increase our likelihood of identifying those patients who have a more biologically disruptive response combined with a more impactful microbial dysbiosis. Current evidence, albeit limited, indicates that for those individuals we should prevent and treat more intensively. This paper discusses what we know and how we might use that information to start individualizing risk and treat some of our patients in a more targeted manner. In my opinion, we are further along than many realize, but we have a great lack of prospective clinical evidence that must be accumulated while we continue to unravel the contributions of specific mechanisms.

Intricate Assessment and Evaluation of Long-term Implant Success as affected by Clinicomicrobial and Salivary Diagnostics in Type II Diabetic Patients: A Longitudinal Study

INTRODUCTION

Replacement of missing teeth by dental implants is one of the most common methods employed these days. Because of significant advancement in the design of implants and modifications in the procedure of dental implant surgery, the survival rate of the dental implants has reached up to approximately 95%. Osseointegration is one of the important factors affecting the survival of dental implants. Apart from these, the body's physiologic alterations can also predispose the dental implants for failure. Diabetes is one such metabolic disease characterized by abnormal or delayed wound healing. Hence, we assessed the clinicomicrobial and salivary profile of diabetic patients undergoing rehabilitation by dental implants.

MATERIALS AND METHODS

This study included diabetic patients who underwent dental implant surgeries for prosthetic rehabilitation. Follow-up records of the patients' up to 1 year were maintained. Various clinicoradiographic and periodontal parameters were measured at various time intervals during follow-up time; 25 mL of salivary and blood sample was taken from all the subjects and was sent to the laboratories for assessment of various salivary biomarkers. All the results were analyzed by Statistical Package for the Social Sciences software.

RESULTS

The mean level of interleukin-p at baseline time was found to be 2.38 and 2.21 in diabetic group and control group respectively. While comparing the levels of osteoprotegerin in both study groups, a significant correlation was obtained. In diabetic and control group, 62 and 61 years was the mean age of the patients respectively. No significant correlation was obtained while comparing the microbial flora of diabetic and control group.

CONCLUSION

In both diabetic and nondiabetic patients, similar microbial, salivary marker, and clinicoradiological patterns were seen.

CLINICAL SIGNIFICANCE

Diabetic patients who maintain their body's metabolic rate show similar success rate of dental implants as seen in nondiabetic patients.

A Randomized Double-Masked Clinical Trial Comparing Four Periodontitis Treatment Strategies: 5-Year Tooth Loss Results

BACKGROUND

Tooth loss is the ultimate negative consequence of periodontitis, and reports of the extent to which different treatment strategies may influence long-term tooth loss are hard to find. This study aims to test the hypothesis that there is no difference in 5-year clinical outcome of therapy in terms of tooth mortality between groups of patients treated with conventional scaling and root planing (SRP) over weeks or same-day full-mouth disinfection (FDIS), with or without adjunctive metronidazole (MET).

METHODS

One hundred eighty-four patients with moderate-to-severe periodontitis were randomly allocated to one of four treatment groups: 1) FDIS+MET; 2) FDIS+placebo; 3) SRP+MET; and 4) SRP+placebo. Total 161 patients (88%) completed the 5-year follow-up examination, and data on number and timing of tooth extractions as well as pre-extraction diagnoses and reasons for extractions were analyzed.

RESULTS

No differences were observed between groups with regard to number of, reasons for, or time of extractions in the four groups at baseline and 1, 3, and 5 years after treatment.

CONCLUSION

If extraction or retention of teeth is regarded as a measure of failure or success 5 years after completion of periodontal therapy, none of the four strategies produced an end result better than the other.

Epidemiology of oral health conditions in older people

The main conditions of interest when considering the epidemiology of oral diseases among older people are tooth loss, dental caries, periodontitis, dry mouth and oral pre-cancer/cancer, along with oral-health-related quality of life (OHRQoL). This article presents an overview of what is known about the epidemiology of each of the main conditions of interest among older populations.

Increased risk for premolar tooth loss in shortened dental arches

OBJECTIVES

To assess sustainability of shortened dental arches (SDA) by determining time to 'first restorative intervention' of teeth and time to 'tooth loss' and comparing these outcomes with complete dental arches (CDA) and SDA plus removable dental prostheses (RDP).

METHODS

Data (follow-up time ranged from 27.4 (SD 7.1) to 35.0 (SD 5.6) years; max. follow up: 45.8 years) from patient records of 59 subjects (23 SDA, 23 CDA, and 13 SDA plus RDP) participating in a prospective cohort study on shortened dental arches (SDA) were analysed. Group effects on survival were analysed using Cox regression models; where appropriate Kaplan-Meier analyses were done.

RESULTS

Compared to SDA subjects, CDA subjects had a lower risk to receive a first restorative intervention in anterior teeth (HR=0.377; 95% CI [0.205-0.695]) and premolars (HR=0.470; 95% CI [0.226-0.977]). CDA subjects had a lower risk to lose premolars compared to SDA subjects (HR=0.130; 95% CI [0.053-0.319]). Risk for 'first restorative intervention' and for 'tooth loss' did not significantly differ between SDA with and without RDP.

CONCLUSIONS

SDA subjects had an increased risk to lose premolars and to receive a first time restoration in anterior teeth and premolars compared to CDA subjects. SDA subjects with RDP had no increased risk to receive a first restorative intervention or for tooth loss compared to SDA without RDP.

CLINICAL RELEVANCE

Subjects with shortened dental arches can be discerned as enduring at-risk patients. It is therefore recommended that shortened dental arch subjects receive intensive and continuous care to prevent further tooth loss.

Influence of attachment and bone loss on the mobility of incisors and canine teeth

OBJECTIVE

The purpose of this clinical study was to evaluate the correlation between tooth mobility (TM), crown-to-root ratio (CRR) and clinical attachment loss (CAL) in periodontally-compromised participants.

MATERIALS AND METHODS

While slowly biting on a load cell, the mobility of the upper incisors and canine teeth of 20 volunteers was measured using a photogrammetric measurement technique. An automated software program recorded the force-related three-dimensional TM at 3-N intervals. CAL was assessed clinically and CRR values were assessed radiographically. For each contralateral pair of teeth (central, lateral incisor, canine) and for each main level of force, the Pearson product-moment correlation coefficient between TM and CRR and between TM and CAL was computed. Correlations were considered statistically significant at p < 0.05.

RESULTS

Statistically significant positive correlations were found between TM and CRR for incisors and canines for each main level of force, whereas canines had the lowest correlation. Statistically significant positive correlations were also found between TM and CAL for the central and lateral incisors at each main level of force. Canines showed no significant correlation between CAL and TM, regardless of force level.

CONCLUSION

The loss of attachment and bone seem to have more influence on the mobility of incisors than canines.

Clinical, microbiological, and salivary biomarker profiles of dental implant patients with type 2 diabetes

OBJECTIVE

Regulators of peri-implant bone loss in patients with diabetes appear to involve multiple risk factors that have not been clearly elucidated. This study was conducted to explore putative local etiologic factors on implant bone loss in relation to type 2 diabetes mellitus, including clinical, microbial, salivary biomarker, and psychosocial factors.

MATERIALS AND METHODS

Thirty-two subjects (divided into type 2 diabetes mellitus and non-diabetic controls), having at least one functional implant and six teeth, were enrolled in a 1-year longitudinal investigation. Analyses of clinical measurements and standardized intra-oral radiographs, saliva and serum biomarkers (via protein arrays for 20 selected markers), and plaque biofilm (via qPCR for eight periodontal pathogens) were performed at baseline and 1 year. In addition, the subjects were asked to respond to questionnaires to assess behavioral and psychosocial variables.

RESULTS

There was a significant increase from baseline to 1 year in the probing depth of implants in the diabetes group (1.95 mm to 2.35 mm, P = 0.015). The average radiographic bone loss during the study period marginally increased at dental implants compared to natural teeth over the study period (0.08 mm vs. 0.05 mm; P = 0.043). The control group harbored higher levels of Treponema denticola at their teeth at baseline (P = 0.046), and the levels of the pathogen increased significantly over time around the implants of the same group (P = 0.003). Salivary osteoprotegerin (OPG) levels were higher in the diabetes group than the control group at baseline only; in addition, the salivary levels of IL-4, IL-10, and OPG associated with host defense were significantly reduced in the diabetes group (P = 0.010, P = 0.019, and P = 0.024), while controls showed an increase in the salivary OPG levels (P = 0.005). For psychosocial factors, there were not many significant changes over the observation period, except for some findings related to coping behaviors at baseline.

CONCLUSIONS

The study suggests that the clinical, microbiological, salivary biomarker, and psychosocial profiles of dental implant patients with type 2 diabetes who are under good metabolic control and regular maintenance care are very similar to those of non-diabetic individuals. Future studies are warranted to validate the findings in longer-term and larger clinical trials (ClinicalTrials.gov # NCT00933491).

Tooth-related risk factors for tooth loss in community-dwelling elderly people

OBJECTIVE

To appropriately explore risk factors for tooth loss operating at the tooth-level, subject-related factors and a hierarchical data structure have to be considered. The purpose of this study was to evaluate tooth-related and subject-related risk factors affecting tooth loss.

METHODS

A 10-year longitudinal survey was carried out on 286 elderly subjects. At baseline, the prosthodontic status and abutment function of the 5574 teeth were recorded. Tooth loss was defined as the main outcome variable, and a multilevel logistic regression model considering subject and tooth levels was applied.

RESULTS

Tooth loss was found in 75% of subjects and most frequently in molars. A multivariable, multilevel logistic regression revealed that the following tooth-related variables were significantly related to tooth loss over 10 years: maxillary teeth, multirooted teeth, single crowns, abutment teeth for a fixed/removable partial denture (FPD/RPD), and periodontally involved teeth. Among them, single crowns, abutment teeth for an FPD, and teeth with severe periodontal disease at baseline had the highest odds of 5.1, 6.0, and 7.1, respectively.

CONCLUSIONS

The findings of this study suggest that tooth loss is the result of complex interactions of tooth-related factors. Several tooth-related variables including multirooted teeth, abutments, and single crowns were found to be possible risk factors for tooth loss. Thus, these findings confirm and underline the potential benefit of minimizing prosthetic treatment of molars.

Gender-dependent associations between socioeconomic status and tooth loss in working age people in the Study of Health in Pomerania (SHIP), Germany

OBJECTIVES

Individual impact and the effect magnitude of socioeconomic key indicators (income, education and occupation) and of gender on oral health are ambiguous. In primary analyses of cross-sectional data among participants of the Study of Health in Pomerania (north-east Germany), women with low school education and low income were at highest risk for missing teeth, whereas being single was a risk indicator for missing teeth in men. Using the 5-year follow-up of this study, we aimed at verifying these findings and at investigating the gender-dependent impact of key socioeconomic indicators on tooth loss.

METHODS

The longitudinal data originate from 1971 subjects (1062 women) aged 25-59 enrolled from 1997 to 2001 and again from 2002 to 2006. The effects of marital status, household income, school education and occupational prestige for tooth loss were examined by gender using negative binomial regression analyses.

RESULTS

Low education and low income were moderately [relative risks (RR) between 1.6 and 2.0] associated with tooth loss among both women and men, whereas occupational prestige was not. After multiple imputations of missing data, less-educated women with lower income exhibited the highest risk of tooth loss [RR=3.1; 95% confidence interval (CI)=1.7-5.5 for <10 years of school education and the lowest income tertile] and tooth loss was more likely in single men (RR=1.5; 95% CI=1.0-2.2) than in single women (RR=0.9; 95% CI=0.6-1.3).

CONCLUSIONS

The primary cross-sectional results were partly confirmed. Socioeconomic factors help to explain differences in tooth loss, although the causal pathways are speculative. To improve dental health, the policies should target not only the individual, e.g. oral health promotion, but also an entire population by better education and higher wage employment.

Periodontal health in Europe: future trends based on treatment needs and the provision of periodontal services--position paper 1

This review gives an update on recent epidemiologic data on periodontal diseases and a description of current periodontal services in Europe. A Medline search of articles published within the last decade with the keywords epidemiology, prevalence, periodontitis, tooth loss, and Europe was performed. Data on provision of dental services originated from international databases. Epidemiologic data on the prevalence of edentulism, the number of missing teeth, the prevalence of probing depth (Community Periodontal Index - CPI >or= 3 or Pocket Depth - PD >or= 4 mm), and clinical attachment loss (CAL >or= 4 mm) displayed a fragmentary picture within Europe. With respect to the limited data on periodontal health, Spain, Sweden, and Switzerland ranked as the healthiest among European countries in contrast to Germany where increased tooth loss and the highest prevalence of CAL >or= 4 mm were reported. The role of dental auxiliaries especially of dental hygienists and/or the medico-legal framework in which they work, appears to be an important factor in provision of effective periodontal care. Actual epidemiologic data on periodontal diseases are non-homogeneous and absent from several European countries. This emphasises the need for more national representative epidemiological studies with a uniform design to permit comparability between different nations. Merging actual epidemiologic data with former data on provision of periodontal care may help to explain differences in periodontal parameters on a population basis and to define future provision of dental care.

Extent of peri-implantitis-associated bone loss

OBJECTIVE

The purpose of the present study was to describe the extent of peri-implantitis-associated bone loss with regard to implant position.

MATERIAL AND METHODS

Patient files and intra-oral radiographs from 182 subjects were analysed. Among the 1070 examined implants, 419 exhibited peri-implantitis-associated bone loss. The position of each implant within the jaw and fixed reconstructions was determined. In the radiographs the distance between the abutment-fixture junction and the most coronal position of bone to implant contact was assessed at the 419 "affected" implants using a magnifying lens (x 7) with a 0.1 mm graded scale.

RESULTS

About 40% of the implants in each subject was affected by peri-implantitis-associated bone loss. The proportion of such implants varied between 30% and 52% in different jaw positions and the most common position was the lower front region. In addition, affected implants were found in larger proportions among "mid" than "end" abutments irrespective of supporting fixed complete or fixed partial dentures.

CONCLUSION

It is suggested that peri-implantitis occurs in all jaw positions and that an "end"-abutment position in a fixed reconstruction is not associated with an enhanced risk for peri-implantitis.

Radiographic alveolar bone loss in patients undergoing periodontal maintenance

The aim of the present cross-sectional investigation was to evaluate percentage of bone loss in patients who had been one year under periodontal maintenance at the Department of Periodontology, Faculty of Dentistry, University of São Paulo by radiographic analysis. Complete sets of periapical radiographs provided data regarding percentage of alveolar bone loss, which was correlated with arches, tooth group and proximal sites. The sample consisted of 27 men and 53 women ranging in age from 16 to 85 years (mean: 48.3 years). A total of 1,120 periapical radiographs (1,970 teeth) were digitized and analyzed with the Image Tool software (University of Texas Health Science Center). Bone loss was defined as when the distance between the cemento-enamel junction and the alveolar bone crest was greater than 2 mm. Two examiners (p<0.0001) performed radiographic measurements of bone loss. The Greenhouse-Geisser normality test and a univariate analysis of variance were used for statistical analysis. Mean bone loss was 20.60% (+/-12.12). The highest level of bone loss was observed on the distal surface and in the upper arch, as well as in the upper incisors and molars.

Risk indicators for missing teeth in working-age Pomeranians--an evaluation of high-risk populations

OBJECTIVE

The goal of this study was to examine whether psychosocial conditions for general health described in the public health literature are also reflected in tooth loss.

METHODS

The relation of psychosocial factors to missing teeth was evaluated among 2,501 individuals aged 25 to 59 years from the population-based cross-sectional Study of Health in Pomerania using logistic regression analyses. The case group included 15 percent of participants of each 5-year age group with the highest number of missing teeth.

RESULTS

Unemployment, dose-dependent current and former smoking, a poor general health status, and a longer time since the last dental appointment were significant risk indicators for missing teeth. Alcohol consumption, use of interdental cleaning products, and checkup as the reason for the last dental visit were protective. Women with low education and low income were identified as a high-risk group for missing teeth by the three-way interaction between gender, school education, and household income. The effect of marital status was modified by gender: being single was a risk indicator for men but it was protective for women.

CONCLUSIONS

The study supports the hypothesis that psychosocial conditions that affect health status as described in the general public health literature also have an effect on tooth loss. Strategies to prevent tooth loss may be expeditiously implemented in combination with approaches to prevent other health-related problems.

The Cost-Effectiveness of Large Amalgam and Crown Restorations Over a 10-Year Period

OBJECTIVE

To assist clinical decision making for an individual patient or on a community level, this study was done to determine the differences in costs and effectiveness of large amalgams and crowns over 5 and 10 years when catastrophic subsequent treatment (root canal therapy or extraction) was the outcome.

METHODS

Administrative data for patients seen at the University of Iowa, College of Dentistry for 1735 large amalgam and crown restorations in 1987 or 1988 were used. Annual costs and effectiveness values were calculated. Costs of initial treatment (large amalgam or crown), and future treatments were determined, averaged and discounted. The effectiveness measure was defined as the number of years a tooth remained in a state free of catastrophic subsequent treatment. Years free of catastrophic treatment were averaged, and discounted. The years free of catastrophic treatment accounted for individuals who dropped out or withdrew from the study.

RESULTS

Teeth with crowns had higher effectiveness values at a much higher cost than teeth restored with large amalgams. The cost of an addition year free of catastrophic treatment for crowns was 1088.41 dollars at 5 years and 500.10 dollars at 10 years. Teeth in women had more favorable cost-effectiveness ratios than those in men, and teeth in the maxillary arch had more favorable cost-effectiveness ratios than teeth in the mandibular arch.

CONCLUSIONS

Neither the large amalgam or crown restoration had both the lowest cost and the highest effectiveness. The higher incremental cost-effectiveness ratio for crowns should be considered when making treatment decisions between large amalgam and crown restorations.

Prognostic model for tooth survival in patients treated for periodontitis

BACKGROUND

In patients with periodontitis, a quantitative prognostic assessment is needed in order to make evidence-based decisions about retaining teeth or extracting and replacing them with a dental prosthesis.

METHODS

One hundred and ninety eight patients receiving active periodontal treatment in 1989 or 1990 and complying with supportive periodontal therapy (SPT) over an average of 11.8+/-2.3 years were included in the study. A generalized linear model was established and fitted via generalized estimating equations to identify predictors for tooth loss during SPT.

RESULTS

Of the 4559 teeth present at baseline, 166 (3.6%) were extracted during active treatment and 249 (5.5%) during SPT. Baseline findings of diabetes mellitus (OR=4.17), reduced alveolar bone levels (OR=1.04 for each 1% increment), increased tooth mobility (III versus 0: OR=5.52), multiple roots (OR=1.82), and non-vital pulp (OR=2.24) were significant (p<0.05) predictors for tooth loss during SPT. Based on these parameters, a prognostic model was constructed that provides estimates of tooth survival probability when periodontal therapy is rendered.

CONCLUSION

Using a multivariate approach, a prognostic model was developed that may be of value for clinical decision making.

Progression of dental caries and tooth loss between the third and fourth decades of life: a birth cohort study

The majority of what is known of the experience of dental caries among adults is from cross-sectional studies, and there are surprisingly few population-level longitudinal studies of dental caries among adults. Dental examinations were conducted at age 26 and again at age 32 among participants in a longstanding prospective study of a birth cohort born in Dunedin (New Zealand) in 1972/1973. Some 901 individuals (88.8%) were dentally examined at both ages. The mean number of remaining teeth and tooth surfaces fell between 26 and 32, reflecting ongoing tooth loss. The overall prevalence of caries rose from 94.9 to 96.8%, while there were greater increases in the proportion with caries-associated tooth loss (from 10.8 to 22.8%). Caries experience was greatest in the molar teeth and upper premolars, and was lowest in the lower anterior teeth. The mean crude caries increment (CCI) was 5.0 surfaces (SD 6.6); 681 (75.5%) experienced 1+ CCI, and the mean CCI among those individuals was 6.6 surfaces (SD 6.9). Substantial dental caries and tooth loss experience occur as people move from the third into the fourth decade of life.

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.