The subject should be examined in the upright position, with the examiner facing the subject with his or her back to the light (window). Natural light to be used. Note the distribution pattern of any defects and decide if they are typical of fluorosis i.e. the defects in the questionable to mild scores (the most likely to occur) may consist of fine white lines or patches usually near the incisal edges or cusp tips. They are paper white or frosted in appearance and tend to fade into the surrounding enamel. They are of a generalised nature and there is usually a definite tendency to bilateral distribution. The premolars and second molars are most frequently affected followed by the upper incisors. The mandibular incisors are least affected.
If fluorosis is present then decide on the two most severely affected teeth. Dean’s Index is scored on the condition of these two teeth. If the two teeth are not equally affected score on the least affected. When scoring, start at the higher end of the Index i.e. severe, and eliminate each score until you arrive at the condition present. If in any doubt the lower score should be given.
Criteria for Dean’s Classification System for Dental Fluorosis (1942)
Criteria –The enamel represents the usual translucent semivitriform type of structure. The surface is smooth, glossy and usually of pale creamy white colour
Criteria – The enamel discloses slight aberrations from the translucency of normal enamel, ranging from a few white flecks to occasional white spots. This classification is utilised in those instances where a definite diagnosis is not warranted and a classification of ‘normal’ not justified
(10-25% of surface)
Criteria – Small, opaque, paper white areas scattered irregularly over the tooth but not involving as much as approximately 25 per cent of the tooth surface. Frequently included in this classification are teeth showing no more than about 1 – 2mm of white opacity at the tip of the summit of the cusps, of the bicuspids or second molars.
(25-50% of surface)
Criteria – The white opaque areas in the enamel of the teeth are more extensive but do involve as much as 50 percent of the tooth.
(100% of surface)
Criteria – All enamel surfaces of the teeth are affected and surfaces subject to attrition show wear. Brown stain is frequently a disfiguring feature
(100% of surface)
Criteria – All enamel surfaces are affected and hypoplasia is so marked that the general form of the tooth may be affected. The major diagnostic sign of this classification is discrete or confluent pitting. Brown stains are widespread and teeth often present a corroded-like appearance.