Enamel cracks. The role of enamel lamellae in caries initiation

Abstract

Lamellae or cracks are distributed throughout tooth enamel in both deciduous and permanent dentitions. While earlier authors postulated that lamellae may be pathways of entry for caries, no evidence was adduced and the theory appears to have been discounted . The present study seeks to show that, at least in some cases, lamellae are permeable to dyes, may be associated with caries initiated in the dentine, supporting the hypothesis of Hardwick and Manly of lamellae penetration by Streptococcus mutans and lactobacilli. The enamel lamellae are shown to be a permeable pathway allowing caries-producing bacteria access to the dentine-enamel junction . Caries can thus be established within the tooth without visible evidence at the surface.

Dental enamel as a dietary indicator in mammals

“…(42) In the enamel of modern humans, posteruption cracks (lamellae) provide pathways for carious infections. (43) The microstructure of enamel has an effect on tooth function because enamel deforms and cracks preferentially between rods rather than across them. (44)(45)(46)(47) Enamel decussation plays an important role in resisting crack propagationit makes the tooth tougher.…”

Influence of enamel wetness on resin composite restorations using various dentine bonding agents: Part I—effects on marginal quality and enamel microcrack formation

“…[20][21][22] The presence of enamel microcrack may increase the risk of microorganism ingrowth and caries formation. 23 However, the relationship between enamel substrate wetness and the post-operative microcrack formation was not investigated.…”

Impulse debracketing compared to conventional debonding

“…1 Irreversible loss of enamel should be minimized, as the outermost enamel layer contains a higher concentration of fluoride ions and is considered to be essential for protection against caries. 2 A variety of factors (eg, the choice of adhesive used for bracket bonding, the particular type of enamel etching, and postprocessing after debonding, as well as the method used for debonding) have been considered to contribute to a potential loss of enamel and the amount of adhesive residue.…”