Deep remineralisation of caries with BioHAP


In Germany, almost half of all children in their first year at school suffer from tooth decay. What is even more alarming is the figures among three-year-olds. Almost one in five have cavities in the teeth that have only just emerged through the gums. Even though milk teeth are completely replaced by permanent teeth by age of about 11, they have important functions. Tooth decay also means children suffer from pain. Pain that can be avoided. A key starting point is cleaning the teeth with a suitable toothpaste that prevents cavities. Since children, particularly toddlers, frequently swallow (almost) all the toothpaste during cleaning, non-toxic active ingredients are recommended. BioHAP (biomimetic hydroxyapatite) is an active ingredient preventing cavities that has been developed based on dental biology.


Can BioHAP remineralise early caries lesions and prevent tooth decay?

Material and methods

This study was conducted by the renowned research group of Amaechi et al. under oral cavity conditions (“in situ”). A total of 30 test subjects took part in the study. Specimens of milk teeth were inserted into the mouths of the test subjects. Some of these specimens already had initial carious lesions. Over a 14-day period, the test subjects either used a children’s toothpaste with fluoride or a children’s toothpaste with BioHAP (KINDER KAREX). After a “washout phase” of 7 days, the groups were switched (“cross-over design”). This was conducted as a double blind study (neither the test subject nor the examiner knew which toothpaste was used). The specimens were then examined using the latest methods. The gold standard for examining such carious lesions is so-called transverse microradiography (TMR).


Both toothpastes remineralise initial carious lesions. Furthermore, both toothpastes prevented the formation of new caries. BioHAP and fluoride result in net-remineralisation while reducing the depth of the lesion. Closer inspection of the specimens revealed that the type of remineralisation was different for fluoride and BioHAP. While fluoride only remineralises the surface of the tooth (and the carious lesion remains intact underneath), BioHAP remineralises the caries evenly (homogenously) deep into the lesion.

Schematic figure by Amaechi et al. 2019: BioHAP evenly remineralises (initial) caries deep into the lesion.
Schematic figure by Amaechi et al. 2019: BioHAP evenly remineralises (initial) caries deep into the lesion.


The children’s toothpaste with BioHAP (KINDER KAREX) is as effective at remineralising (initial) carious lesions as the control toothpaste with fluoride. However, BioHAP results in even remineralisation deep into the lesion.

The publication of the study can be found here.

Source: Amaechi, B. T. et al. Comparative efficacy of a hydroxyapatite and a fluoride toothpaste for prevention and remineralization of dental caries in children. BDJ Open 5, 18 (2019).