Thesis (M.Sc.D.)--Boston University, School of Graduate Dentistry, 1973 (Pedodontics) / Bibliography included.

No description available.

Thesis (Ph.D.(Community dentistry))--University of Pretoria, 2008. / Includes bibliographical references (leaves 177-186)

Thesis (M.S.)--University of Michigan, 2002. / Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 2002. / Includes bibliographical references.

Thesis (M.P.H.)--University of Michigan, 1942.

Thesis (M.P.H.)--University of Michigan, 1942.

OBJECTIVE: Caries risk assessment tools operate on the subject level. The aim of the study is to create new caries risk assessment models that functions on the tooth and surface level to assess the risk of caries of single teeth and surfaces. METHODS: Secondary data from the Dental Longitudinal Study was used to evaluate caries symmetry. Teeth were grouped into posterior and anterior teeth. Surfaces were grouped into fissured, proximal, and facial and lingual surfaces. The prediction of future caries on a tooth or a surface by the current caries on a bilateral or adjacent tooth or surface was evaluated. Additional general and oral caries risk factors on teeth and surfaces were adopted from the American Dental Association caries risk assessment tool. Caries on bilateral and/or adjacent teeth or surfaces were augmented with significant oral clinical caries predictor to build the caries risk assessment tools for teeth and surfaces. The models were validated by calculating sensitivities and specificities. RESULTS: 495 subjects with baseline and three year follow up data were included in the study. Caries prevalence and incidence was symmetrical (right and left) on the population level. On the individual level, caries incidence was symmetrical (right and left) and also tends to affect adjacent teeth or surfaces. Baseline caries on bilateral and adjacent teeth and surfaces was predictive of caries at follow up in all groups of teeth and surfaces except posterior teeth. Local oral caries risk factors like visible plaque, interproximal restorations, and xerostomia significantly predicted caries on single teeth and surfaces. Tools of caries risk assessment for anterior teeth and the three groups of surfaces were built. The sensitivities of these tools ranged between 67.33% to 85.51 %, specificities ranged between 38.40 % to 66.11%, and the overall accuracies ranged between 41.95% to 66.27%. CONCLUSION: Dental caries is a symmetrical disease affecting the right and left sides of the mouth equally. Past caries experience is significant in predicting future caries. New models were built to assess caries risk for anterior teeth, fissured surfaces, proximal surfaces, and facial and lingual surfaces with acceptable accuracy. / 2018-09-28T00:00:00Z

Dental caries is caused by acidogenic oral micro-organisms which convert fermentable carbohydrates to acids that damage the tooth by causing a demineralisation and disintegration of the inorganic and organic substances of the tooth, respectively (Soames and Southam, 2005). In horses, two variants of dental caries occur: equine dental peripheral caries (PC) involving the periphery of teeth; and infundibular caries (IC) of the maxillary cheek teeth. Twenty-five veterinarians and equine dental technicians experienced in equine dentistry were recruited to perform a UK-wide survey and examined 706 horses for the presence PC and IC, as well as for concurrent dental disorders. The recorded survey results for individual horses included data on potential risk factors including breed, sex, age, diet and the postcode of stables. The prevalence of PC and IC in this population, was 51.7% and 45.5%, respectively. The most commonly and severely PC affected teeth were the three caudal cheek teeth (Triadan 09-11) and for IC were the Triadan 09s. In a multivariable model without observer as a random effect, potential risk factors for the development of PC were: the presence of IC, the presence of diastema/periodontal disease (PD), the presence of multiple concurrent dental disorders other than IC, being fed 2.1-3.0 kg concentrates per day, and living in South East England and South West England. The risk factors which remained significantly associated with the presence of PC in a multivariable model with observer as a random effect, were: feeding 2.1-3 kg concentrates per day, multiple concurrent dental disorders other than IC, the presence of diastema/periodontal disease; additionally, dental fractures now became significantly associated with the presence of PC. In a multivariable model without observer as a random effect, potential risk factors for the development of IC were: the presence of PC, the presence of multiple dental disorders other than IC, and increasing age. Horses in North England and South West England were significantly less likely to have IC than horses in other regions of England and Scotland. In a multivariable model with observer as random effect, the only remaining risk factors were increasing age and geographical region, with a significantly lower likelihood for horses to have IC in South West England than in the other regions. A molecular microbiological study on equine dental caries using a linear discriminant analysis effect size (LEfSe) at genus or higher level, showed Gemella and Actinobacillus to be the genera most associated with the PC study control group (no PC), and Streptococcus, Olsenella and Scardovia to be the genera most associated with PC. Additionally if LEfSe was performed at genus level only, then an additional genus shown to be associated with PC was Mitsuokella. The genus most associated with IC using LEfSe at genus or higher level was Acidaminococcus, while Bacillus was the genus most associated with the IC study control group (no IC). A pathological study examined PC-affected cheek teeth grossly, histologically and, by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Dental plaque, containing bacteria was found to cover the PC lesions. In peripheral cementum, PC lesions were categorised by their shape on histological cross sections of affected teeth into: flake-type, flask-like, or ellipsoid-shaped lesions or combinations of these patterns. Bacteria from surface lesions penetrated between Sharpey's fibers of cementum in a direction perpendicular to the peripheral aspect of the tooth, destroying the intrinsic fibres and Sharpey's fibers. Bacteria also penetrated in a direction parallel to the peripheral aspect of the tooth, undermining the intrinsic fibres, including at the level of incremental growth lines. Bacteria were also found in ellipsoid-shaped lesions and in cemental lacunae of affected cementum. In dentine affected by PC, bacteria were found within and between damaged dentinal tubules, sometimes causing flake-type lesions similar to those seen in cementum. Bacteria penetrated primary dentine and/or (regular/irregular) secondary dentine from the occlusal surface, or entered primary dentine through cementum and enamel from the peripheral aspect. Dental plaque containing bacteria were sometimes observed in dentinal fissure fractures. PC of enamel was only visible using SEM, because this was the only method which did not require prior decalcification, that almost completely removed enamel. In conclusion, PC and IC are prevalent dental disorders in the examined British equine population. The association between PC and concurrent dental disorders (multiple concurrent dental disorders, diastemata/periodontal disease and dental fractures), indicates that these should be addressed in affected horses. In horses affected by IC, the focus should be on treatment of IC itself (like infundibular fillings), because associations of IC were found with risk factors which cannot (or not easily) be controlled such as age and region. Several bacteria could be identified which were associated with PC and other bacteria were more associated with IC or control groups. It was confirmed in the pathological study that bacteria penetrate the cheek teeth affected by PC and IC. So the focus of treatment of PC and IC can also be on reducing the bacteria associated with PC and IC respectively, or the focus could be on prevention by making the teeth more resistant against caries by fluoride treatment. A critical assessment of the use of chlorhexidine mouthwashes and supplementation of fluoride are needed to evaluate its potential effects on PC and IC.

The aim of the present thesis was to find a test for prediction of caries activity which would be useful in routine clinical work.Correlations between oral health, general health, food habits and socioeconomic conditions were investigated in 4- and 8-year-old children. It was found that the salivary secretion rate and the prevalence of oral lactobacilli were factors which might be useful in caries prediction.In 5- and 8-year-old children negative correlations between caries frequency and secretion rate, pH and buffer effect of saliva were demonstrated. However, these parameters showed a wide range of variation.A dip-slide test (Dentocult®), for determination of the number of lactobacilli in saliva, were investigated. The test proved to be reliable for determining of the number of lactobacilli in saliva.The clinical use of information on salivary secretion rate and number of lactobacilli in saliva in prediction of caries activity was examined in 115 14-year-old children over a period of 64 weeks. The number of lactobacilli in saliva, but not the salivary secretion rate, was correlated to caries activity. The number of lactobacilli in saliva seems to reflect the frequency of ingested fermentable carbohydrates and indirectly the risk for initiation of carious lesions. However, when the lactobacillus test is used it is important that there are no such areas of microbial retention on the teeth, as open cavities, poorly executed conservations, dentures or orthodontic bands. The lactobacillus test would make it possible to individualize prophylactic caries treatment. / <p>Annan ISSN på omslaget och titelblad (ISSN 0934-7532).</p><p>Härtill 5 delarbeten.</p> / digitalisering@umu