What is that black stain?

Image of black stains on teethActinomyces/Black Stain

Have you ever had a young patient come to your office with strange black staining? Something we see from time to time are children who present with superficial black stains on the teeth. Parents will always ask what causes it, and usually we discuss things like water and vitamins, but often we throw our hands in the air because the answer seemed elusive. Well, this recent study might shed some light on what is going on:



Assess prevalence, familial predisposition and susceptibility to caries of Black Stains (BS). Evaluate the microbiological composition of BS, saliva and subgingival plaque.


Sixty nine subjects with BS (test group) and 120 subjects without BS (control group) were analysed for oral status. For each BS-patient, a BS-deposit, 1 ml of saliva and subgingival plaque were collected and microbiologically analysed. Five deciduous teeth with BS were observed under SEM.


This study showed a BS prevalence similar to that of the Mediterranean area and a familiality. The microbiological origin of BS was confirmed by SEM and culture method and the BS flora differ from that of supragingival plaque.


Predominance in BS and saliva of Actinomycetes and the low salivary prevalence of S. mutans and L. acidophilus may be related with low caries incidence in BS patients. The high presence of Actinomyces spp can be a causative factor for BS.

(Tripodi D, Martinelli D, Pasini M, Giuca MR, D’Ercole S. Black Stains: a microbiological analysis and a view on familiarity and susceptibility to tooth decay of patients in childhood. Eur J Paediatr Dent. 2016 Dec;17(4):261-266. 69+BS, 120 –BS, 5 Decid teeth.)

So what can we tell our patients when they are concerned about their children? Patients with black stains typically have low caries incidence and high presence of the bacteria Actinomyctes causing the black coloration. It turns out the black stain is a bacterial origin issue, and seems to not be anything serious.



Professional Login