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P Gaengler

Publications and source records attributed to P Gaengler.

25 records · Page 2Linked to original sources
PubMed1992

The periodontal differentiation in the phylogeny of teeth--an overview.

During the evolution of teeth, different types of periodontal attachment have been developed. On the basis of the comparative histology of periodontal tissues, protoacrodontal, acrodontal, acro-protothecodontal, pleurodontal and thecodontal structures can be distinguished that depend upon the area of attachment (crestal, marginal or socketed type) and the mode of attachment (ankylosis, fibrous or combined type). Due to "phylogenetic memory", changes of the periodontium in health and disease could be interpreted as copies of phylogenetically older patterns. The greatest variations in tooth attachment have originated in acrodont bony fishes and in pleurodont reptiles, whereas the selection for a single thecodont or socketed type was an important event in the evolution of mammals. The detailed structures of cementum, of the fiber apparatus and of the junctional epithelium vary from type to type and within one type. These principal structures are decisive for reaction patterns of degeneration and regeneration. Therefore, comparative periodontology could be an important adjunct to help interpret the natural history of periodontal diseases, to help in the selection of experimental animals and to help provide treatment strategies in both human and veterinary situations.

Animals↗
PubMed1988

Assessment of periodontal disease and dental caries in a population survey using the CPITN, GPM/T and DMF/T indices.

2263 randomly selected subjects, aged 15-19, 20-24, 25-29, 30-34, 35-44, 45-54, 55-64, and greater than 64 yr, were assessed for periodontal status, caries status and treatment needs using the Community Periodontal Index of Treatment Needs (CPITN), the ratio of Gingivitis: Periodontitis: Missing teeth (GPM/T index) and the DMF/T index. The advantages of full mouth examination were compared to partial recordings. The CPITN underestimated deep pocketing especially in older age groups and in younger groups overestimated the need for scaling. Although the mean GPM/T number of periodontally affected teeth is in the range of 9-13 teeth and stable throughout the age groups there were age-dependent high risk groups for developing shallow pocketing (20-24 yr) and deep pocketing (45-54 yr), whereas adolescents were at high caries risk. The increase in the number of missing teeth was dramatic after the age of 54 yr only one decade after the high risk age for deep pathologic pockets.

Adolescent↗
PubMed1984

Prevalence and distribution of gingivitis, periodontitis and missing teeth in adolescents and adults according to GPM/T index.

The purpose of the present study was to determine the distribution and the prevalence of periodontal disease in adolescents and adults using the WHO method TRS 621 and to propose a method of presenting the results by a simple index system. On the basis of a medium term longitudinal 5-yr project 1048 subjects were examined in age group 1 (15-19 yr) and 425 subjects in age group 2 (35-44 yr). Each subject had a full mouth examination for the presence of supra- or subgingival calculus, pocketing, bleeding and recession and the PI (Russell). These epidemiologic data were characterized by the ratio Gingivitis:Periodontitis:Missing teeth by using solely the recordings for bleeding, pockets and missing teeth. The mean GPM index in Group 1 was 15.4:0.6:0.8. The mean GPM index in Group 2 was 12.0:4.6:7.7. The Periodontal Index is more subjective than the TRS 621 method. Full mouth recording is required for the suggested GPM/T index analogous to the DMFT index. This new scoring ratio makes it possible to present data of the progression rate of periodontal disease by the increment of tooth related P/T and M/T. Both indices with the common M-value (Missing) might be used for longitudinal programs of control and prevention of periodontal disease and dental caries.

Adolescent↗
PubMed1984

In vivo remineralization of human enamel and dental calculus formation.

The aim of this investigation was to determine the inorganic composition and the surface morphology of remineralized enamel areas and of dental calculus in heavy-calculus-formers (five subjects) and to compare these results with those of non-calculus-formers (two subjects). Electron probe micro-analysis (EPMA) was carried out on sound, acid-etched, and in vivo remineralized enamel samples from heavy- and non-calculus-formers. The mean values of Ca, P, Na, Mg, Al, Si, S, Cl, and K were compared with the SEM morphology. EPMA measurements showed no significant differences in the Ca/P ratio of the surface layers of prism-oriented and/or homogeneous enamel remineralization. The variations of remineralization pattern after acid-etching are similar in teeth from heavy dental-calculus-forming patients and in teeth from non-calculus-formers. The SEM appearances of remineralized areas and of the inner surface of mature dental calculus must be considered to be totally different. The experiments carried out suggest that the remineralization of enamel is not related to the formation of calculus.

Calcium↗
PubMedDate not supplied

Correlation between clinical scoring of secondary caries at crown margins and histologically assessed extent of the lesions.

PURPOSE: The aim of this study was to propose a new clinical diagnostic rating index for secondary caries lesions at crown margins and to correlate this index with histologic evaluations. MATERIALS AND METHODS: Based on criteria for the evaluation of root caries, a modification of secondary caries lesions at the crown margin (SC index) was applied; the lesion characteristics were described as SCO to SC4. A total of 16 crowned teeth exhibiting secondary caries were randomly selected. The teeth were rated and grouped according to their clinical SC grades (SC1 to SC4). After embedding in Technovit, the teeth were serially sectioned and histologic caries scores were given for each section. RESULTS: Fifty-two percent of the prepared margins were in cementum/dentin. Crown margins with no caries lesions were mainly found in teeth clinically rated as SC1 and exhibiting localized discolorations, whereas deep lesions were found histologically at teeth rated SC4. The nonparametric test according to Spearman's rank correlation coefficient (rho) confirmed a highly significant correlation between the clinical SC index and the histologic evaluation (rho = 0.87, 95% confidence interval = 0.67 to 0.96, P < 0.01). SC1 discolorations overestimate caries lesions, whereas SC2 and SC4 lesions are well correlated to the percentage of histologically evaluated caries extension into all sections of a tooth. Lesions rated SC3 demonstrated a high variability of caries penetration into the dentin. CONCLUSION: The depth of discolorations and circular lesions is clinically not well predictable. Clinical diagnosis for localized superficial caries and deep caries lesions at the crown margin correlated well with the histologic caries rating.

Adult↗