DOI: 10.1051/odfen/2013306 J Dentofacial Anom Orthod 2013;16:404 Ó RODF / EDP Sciences Spots on tooth enamel: what’s new? Muriel DE LA DURE-MOLLA, Chantal NAULIN-IFI, Katia JEDEON, Ariane BERDAL, Sylvie BABAJKO ABSTRACT Enamel is the most visible tissue of the tooth. It gives the tooth its whiteness, its brilliance and is the main focus of our attention from an esthetic point of view. Unfortunately, it is not uncommon to see alterations in this enamel, whether they are simple localized discolored spots, or more extensive loss of tooth substance. The etiologies, then, are multiple: toxicity during the mineralization of the bud, hyperthermia or a genetic abnormality. As professionals, making an etiological diagnosis and reassuring the parents is a challenge that we must address on a daily basis. KEY WORDS Dysplasia Amelogenesis Hypomineralization Enamel Even though the enamel is the hardest comprised of three distinct entities: hypo- tissue of the tooth, paradoxically, it is also plasias, hypomineralizations and hypoma- biologically the most brittle. In fact, defects turations (Fig. 1). in the enamel presenting most often as –Hypoplasiasare quantitative altera- spots or as loss of tooth substances are tions caused by a defect of secretion much more frequent than abnormalities of of the enamel matrix. Clinically, this the dentin or cement. From a terminologi- leads to a loss of localized tooth cal standpoint, any alteration in the enamel substance, or a decrease in thickness can be designated by the generic term of enamel layer. The remaining enamel, ‘‘enamel dysplasia’’. This dysplasia is Address for correspondence: Article received: 03-2013 Muriel de La Dure Accepted for publication: 04-2013 Private practice 1 121 boulevard Jean Jaure`s 92100 Boulogne Bilancourt [email protected] Article available at http://www.jdao-journal.org or http://dx.doi.org/10.1051/odfen/2013306 MURIEL DE LA DUREMOLLA, CHANTAL NAULIN-IFI, KATIA JEDEON, ARIANE BERDAL, SYLVIE BABAJKO therefore complains about signif- icant pain with changes in tem- perature and when chewing hard foods. Each of these alterations corresponds to a histological defect occurring during specific stage of anamelogenesis. Hypoplasias arise during the secretion stage, hypomaturations during the ma- turation stage and hypomineralizations during the enamel extracellular matrix mineralization5. The prevalence of defects in the en- amel is greater in permanent teeth than in deciduous teeth, but extremely vari- Figure 1 able from one study to the next. In fact, Summary diagram of the different clinical alterations the prevalence is from 24% to 49% in the enamel. (40.2% in Spain) for temporary teeth and from 9% to 63% (52% in Spain) for 6 on the other hand, is very hard permanent teeth . Of course, enamel and its coloring is normal or defects arising in the permanent denti- slightly yellow. tion concern parents the most, espe- – Hypomaturations and hypomi- cially when they appear in the anterior neralizations are, conversely, sectors. Parents are concerned about qualitative defects where the various issues: the esthetics, the risk of very mineralization process itself seeing other teeth affected and the risk is altered. The organic matrix is for brittleness of the affected tooth. But therefore excessive. Strictly the first question that the parents ask is speaking, with hypomaturation, often ‘‘where did it come from’’? the decrease in mineralization is The etiologies are then extremely less severe than in hypominera- variable: traumatic, systemic and ge- lization. Hypomaturation gener- netic. Clinical examination, medical ally shows up as an alteration in history, questioning of the parents the color of the enamel varying concerning the growth, life style and from chalky white to dark brown. the home environment of the child On the other hand, there is no provide information for positive and loss of enamel in the affected differential diagnosis. The first step area. of this diagnosis is to determine how – Hypomineralization is the most many teeth are affected. severe alteration of the enamel. – When a single tooth is affected, The degree of mineralization is the etiological factor is therefore reduced which leads to brittle, local. It is necessary to discover if soft when probed and rapidly there was an earlier trauma that worn enamel. It is a dark yellow occurred to the primary tooth or even orange color. The patient (especially, a traumatic intrusion). 2 De La DureMolla M., Naulin-Ifi C., Jedeon K., Berdal A., Babajko S. Spots on tooth enamel:what’s new? SPOTS ON TOOTH ENAMEL: WHAT’S NEW? The root of the primary tooth will exert force on the bud of the permanent tooth during morpho- genesis and therefore disturb the amelobastics layer. This type of trauma most frequently involves the incisors. The 2nd possible local etiological factor is infection. In fact, if an infection presents on a primary molar and propagates to Figure 2 the succesional tooth during its Intraoral view of a patient with mild to morphogenesis, this will cause an moderate dental fluorosis. abnormality in the permanent tooth that is then referred to as a mineralization at that age, namely the ‘‘Turner’s tooth’’. The premolars permanent incisors, the 1st perma- are teeth most affected by this nent molars, some of the canines disorder. and premolars. The 2nd molars are – When several teeth are affected, very rarely affected by fluorosis. the etiology to consider therefore Since this pathology is well known is systemic toxicity, that’s mean now, its prevalence decreased con- prolonged exposure to a factor that siderably ranging from 3.9% in 1991 alters amelogenesis. to 2.73% in 1998 in France. – Fluorosis: Fluoride was the first enamel toxin – MIH: Molar Incisor Hypominer- described. In fact, an overdose of alization: fluoride, namely an intake of fluoride In 2001, Weerheijm defined MIH greater than 1.5 mg/j, is responsible as being a ‘‘hypomineralization of for dental fluorosis. This dosage is systemic origin frequently affecting reached very quickly. In fact, by way 1-4 permanent first molars whether of comparison, drinking water has a associated or not with affected per- 9 fluoride content on average varying manent incisors’’ . The damage can From 0.3 to 0.5 mg/l. The prophylac- be mild, moderate or severe. In the tic dose is 0.05 mg/kg/j. The serious- mild forms, we see limited white or ness of enamel alteration varies, light yellow spots. from ‘‘very mild’’ forms to ‘‘severe’’ In moderate forms, these spots forms according to Dean classifica- are more extensive, ranging from tion in 1942. The mildest form is white to brown. And in the severe characterized by limited small opaque forms, these spots are associated areas affecting at least half of the with hypoplasias. The severity of dental surface and the severe form is the damage to the incisors generally characterized by brown or even black indicates the severity of the molar in- stains combined with areas of hypo- volvement, whereas the converse is plasia (Fig. 2). Excessive intake of not true. Generally, the spots are fluoride generally occurs during the well-defined on the incisors, espe- first years of a child’s life. Fluorosis cially impacting the buccal surface. then affects all the teeth during At the level of the molars, on the Rev Orthop Dento Faciale 2014;17:404. 3 MURIEL DE LA DUREMOLLA, CHANTAL NAULIN-IFI, KATIA JEDEON, ARIANE BERDAL, SYLVIE BABAJKO Figure 3 a-b: Intraoral views showing un incisor and a permanent molar affected by MIH. The incisors present white and yellows stains that are well defined. The molar presents a localized brown spot on the occlusal surface combined with a hypoplasia of the enamel on the bucco-distal sur- face of the cuspid. c: Microscopic photograph of a cut of a tooth presenting a localized white spot on the palatal surface. d: Scanning electron microscope photograph of the pre- vious cut that visualizes a deformation in the thickness of the enamel in the area affected by MIH as well as a decrease in mineralization (dark gray areas). other hand, they are more diffuse Different criteria should be taken and especially affecting the occlusal into account for the diagnosis: surface and the buccal surface. The – the presence of well-defined damage is not symmetrical either in opacities either white, yellow or relation to the affected tooth nor in brown in color; relation to the severity of the damage – post-eruptive losses of enamel from one tooth to the other in the due to abrasion of the hypomi- same patient. All the other perma- neralized enamel; nent teeth are healthy, only the inci- – atypical restorations; sors and permanent first molars are – extractions of the first molars affected. These hypomineralizations combined with damage to the make the enamel extremely suscepti- incisors in a patient who presents ble to wear and to caries (Fig. 3). The a low risk for caries. molars are the teeth most affected When the incisors are the only by this phenomenon of a carious le- teeth affected, MIH can be ruled out. sion that then will develop very ra- The etiology of MIH is still un- pidly. It is not uncommon to see known. Numerous epidemiological caries approaching the pulp on teeth studies have been carried out, with- that are still erupting. An histological out really pinpointing any causal analysis of these teeth confirms factor. The only certain finding is that hypomineralization of the enamel in one or more toxic factors occurred the affected area. Prisms are then during the end of pregnancy or separated from one another by the during the first years of life of the non-degraded organic matrix render- child. In fact, this period corresponds ing the enamel permeable to micro- to the period of mineralization of organisms3.