Natural history of periodontitis: Disease progression and tooth loss over 40 years.

OBJECTIVES: To assess long-term attachment and periodontitis-related tooth loss (PTL) in untreated periodontal disease over 40 years. MATERIAL AND METHODS: Data originated from the natural history of periodontitis study in Sri Lankan tea labourers first examined in 1970. In 2010, 75 subjects (15.6%) of the original cohort were re-examined. RESULTS: PTL over 40 years varied between 0 and 28 teeth (mean 13.1). Four subjects presented with no PTL, while 12 were edentulous. Logistic regression revealed attachment loss as a statistically significant covariate for PTL (p < .004). Markov chain analysis showed that smoking and calculus were associated with disease initiation and that calculus, plaque, and gingivitis were associated with loss of attachment and progression to advanced disease. Mean attachment loss <1.81 mm at the age of 30 yielded highest sensitivity and specificity (0.71) to allocate subjects into a cohort with a dentition of at least 20 teeth at 60 years of age. CONCLUSIONS: These results highlight the importance of treating early periodontitis along with smoking cessation, in those under 30 years of age. They further show that calculus removal, plaque control, and the control of gingivitis are essential in preventing disease progression, further loss of attachment and ultimately tooth loss.

Evaluating the agreement of skeletal age assessment based on hand-wrist and cervical vertebrae radiography.

INTRODUCTION: The aim of this study was to examine the agreement of skeletal age assessment based on hand-wrist radiographs with cephalogram-based cervical vertebrae evaluation. To circumvent bias and loss of information from staging, a quantitative approach was applied to determine morphologic changes. METHODS: We analyzed 730 sets of radiographs (cephalogram and hand-wrist) of untreated subjects (352 boys, 378 girls; age range, 6-18 years) from a growth study, each sex as a separate sample. Skeletal age was determined on the hand-wrist radiographs according to the method of Greulich and Pyle. Morphometric changes of the vertebral bodies C2 through C4 were measured (concavity, anterior height, and angle) and tested for correlations with the method of Greulich and Pyle. All correlating variables were included in a multiple linear regression to generate a calculated skeletal age. To establish the agreement between the method of Greulich and Pyle and calculated skeletal age, Bland-Altman plots were made, limits of agreement were identified, and cross-tables (before and after peak height velocity) were computed. Similarly, the agreement between the method of Greulich and Pyle and each subject's chronologic age was estimated for comparison. RESULTS: Concavity of C2, C3, and C4; anterior height of C3 and C4; and the angle of C3 correlated with skeletal age highly significantly (P <0.0001) in both sexes, and calculated skeletal age was established based on a linear regression. The agreement between the method of Greulich and Pyle and calculated skeletal age was modest (limits of agreement: boys, ±3.5 years; girls, ±3.3 years) and substantially weaker than the agreement between the method of Greulich and Pyle and chronologic age (limits of agreement: boys, +2.1 to -1.7 years; girls, +2.2 to -1.2 years). Similarly, calculated skeletal age resulted in considerably more false predictions of peak height velocity (boys, 18.9%; girls, 12.9%) than did chronologic age (boys, 7.1%; girls, 7.4%). CONCLUSIONS: Morphometric assessment of age-dependent changes in the cervical spine offers no advantage over chronologic age, in either assessing skeletal age or predicting the pubertal growth spurt.

The clinical course of chronic periodontitis: V. Predictive factors in periodontal disease.

BACKGROUND: The factors associated with initial periodontitis are not well understood and cannot be identified by cross-sectional studies. AIM: To identify the factors associated with the initiation of chronic periodontitis using ante-dependence modelling. MATERIAL AND METHODS: A 26-year longitudinal study of the natural history of periodontitis served as the basis for the study. In 1969, 565 Norwegian men aged 16-34 years were surveyed. Subsequent surveys were performed in 1971, 1973, 1975, 1981, 1988 and finally in 1995, with 223 remaining subjects. Plaque (PlI), gingival (GI) and calculus indices (CI) and loss of attachment (LoA) were recorded. Ante-dependence modelling using a Markov chain enabled the results of this sequence of examinations to be analysed longitudinally, taking into account serial dependence, describing temporal changes in patients' levels of disease and allowing for both progression and regression between disease categories. RESULTS: With age, the rate of disease regression decreased. Increasing calculus accumulation and smoking increased the rate of disease progression, while increasing GI increased the rate of regression. CONCLUSIONS: Increased mean CI and smoking were significant predictive covariates for progression, while increased mean GI and younger age predicted regression of initial periodontitis.