A reaction-time study of social, health, and personal attributions in relation to fluorosed teeth

Fuzzy K-Nearest Neighbor Based Dental Fluorosis Classification Using Multi-Prototype Unsupervised Possibilistic Fuzzy Clustering via Cuckoo Search Algorithm

Dental fluorosis in children is a prevalent disease in many regions of the world. One of its root causes is excessive exposure to high concentrations of fluoride in contaminated drinking water during tooth formation. Typically, the disease causes undesirable chalky white or even dark brown stains on the tooth enamel. To help dentists screen the severity of fluorosis, this paper proposes an automatic image-based dental fluorosis segmentation and classification system. Six features from red, green, and blue (RGB) and hue, saturation, and intensity (HIS) color spaces are clustered using unsupervised possibilistic fuzzy clustering (UPFC) into five categories: white, yellow, opaque, brown, and background. The fuzzy k-nearest neighbor method is used for feature classification, and the number of clusters is optimized using the cuckoo search algorithm. The resulting multi-prototypes are further utilized to create a binary mask of teeth and used to segment the tooth region into three groups: white-yellow, opaque, and brown pixels. Finally, a fluorosis classification rule is created based on the proportions of opaque and brown pixels to classify fluorosis into four classes: Normal, Stage 1, Stage 2, and Stage 3. The experimental results on 128 blind test images showed that the average pixel accuracy of the segmented binary tooth mask was 92.24% over the four fluorosis classes, and the average pixel accuracy of segmented teeth into white-yellow, opaque, and brown pixels was 79.46%. The proposed method correctly classified four classes of fluorosis in 86 images from a total of 128 blind test images. When compared with a previous work, this result also indicates 10 out of 15 correct classifications on the blind test images, which is equivalent to a 13.33% improvement over the previous work.

Aesthetic perception of dental fluorosis--opinions of dentists and non-specialists

Aesthetic perception of the changes in teeth appearance is one of the factors that makes a person undertake a dental treatment.

OBJECTIVE

The aim of this study was to survey dentists' and non-specialists' aesthetic perception of dental fluorosis.

PATIENTS AND METHODS

We recruited 120 young people (age range 18-22 years with little knowledge of dental fluorosis and 120 randomly selected dentists. Evaluation of the abnormalities in the teeth aesthetic appearance was conducted using cards specially designed for the purpose.

RESULTS

The results suggest that changes in dental fluorosis, even in the mildest forms, are perceived as deviations in the aesthetic appearance of teeth. Non-specialists are more tolerant towards the changes characteristic of mild dental fluorosis compared with their reaction to other conditions that result in deviations in the type of dentition as a whole.

CONCLUSION

Further studies are needed to more precisely determine the role of aesthetic perception in determining the indications for the complex treatment of dental fluorosis.

A literature review of aesthetic perceptions of dental fluorosis and relationships with psychosocial aspects/oral health-related quality of life

Aesthetic perceptions and oral health-related quality of life concerning dental fluorosis have been assessed in several studies during the past two decades. However, no comprehensive review article summarizing the studies investigating this issue has been published.

OBJECTIVE

To assess the relationships between perceptions of dental appearance/oral health-related quality of life (OHRQoL) and dental fluorosis.

METHODS

The PubMed database was searched using the Medical Subject Headings (MeSH) for English-language studies from 1985 to March 2009. Thirty-five articles qualified for inclusion and then were classified into three categories based on the type of study approach: (i) respondent review of photographs and assessment concerning satisfaction/acceptance, (ii) respondent assessment of study subject's teeth concerning satisfaction/acceptance, and (iii) respondent assessments of the psychosocial/OHRQoL impact.

RESULTS

There were varied results from earlier studies focused on satisfaction/acceptance of very mild to mild fluorosis. More recent studies with methodological improvements to assess impact on quality of life clearly showed that mild fluorosis was not a concern. Furthermore, mild fluorosis was sometimes associated with improved OHRQoL. Severe fluorosis was consistently reported to have negative effects on OHRQoL.

CONCLUSION

Because dental fluorosis in the United States and other nations without high levels of naturally-occurring fluoride is mild or very mild, with little impact on OHRQoL, dental professionals should emphasize the appropriate use of fluorides for caries prevention and preventing moderate/severe fluorosis.