Identification and indexing of lattice planes through high-resolution transmission electron microscopy provided precise measurements of intertubular crystals of arrested caries in dentine compared to sound dentine. In arrested caries, mean crystal width was 310 Å (SD 44) with a range from 200 to 400 Å. Mean thickness was 86 A (SD 19.3) with a range from 57 to 130 Å. In sound dentine, mean width was not very different at 296 Å (SD 39) with a similar range from 200 to 400Å. Mean thickness was lower: 31.6 Å (SD 5.4) with a range from 24 to 41 Å. A growing process due to thickening of the crystallites was pointed out. The coexistence of whitlockite and apatite within the large crystals of intratubular dentine in arrested caries was shown through high-resolution electron microscopy and micro-electron diffraction. Two stages of arrested caries could be found at the crystal level: firstly, a precipitate of the material dissolved at the very beginning of the carious process, and secondly, remineralization of decalcified dentine by growth of residual crystals (intertubular dentine) and by a maturating process of whitlockite towards apatite (intratubular crystals).

Our study explored the influence of diet on gliomagenesis and associated systemic effects (SE) in rats. The experimental diet contained various ingredients supposed to interfere with carcinogenesis, mainly phytochemicals (PtcD for phytochemical diet) and its effects were compared to those of the same diet without the phytochemicals (BD for basal diet). Glioma was induced by ethylnitrosourea to pregnant females fed the diets from the start of gestation until the moment of sacrifice of the offpsrings. In male rats fed the PtcD or the BD the incidence of gliomas was markedly reduced compared to rats fed a standard diet (StD). In females this effect was weaker and was limited to the PtcD. A significant proportion of rats with brain tumors and fed the StD exhibited SE evidenced by weight loss, a shorter survival, reduction in liver weight and an increased proportion of liver mitochondria, effects that were not observed in their counterpart fed PtcD. Comparison of the expression of genes involved in the balance proliferation/apoptosis and in the response to oxidative stress in male brain tumors showed that the prevention of SE was associated with an increase in bcl-2 and catalase and a decrease in ki-67, sod-1 and sod-2 transcripts. These results show that the degree of agressiveness of gliomas can be modulated by dietary interventions and suggest that some phytochemicals with antioxidant properties could participate to the mechanism.

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A combination of preventive methods have been used to reduce dental caries in children aged 7-8 at baseline, living in a non-fluoridated area in the West of France. The preventive program involved a daily supervised toothbrushing at school with 180 mg of fluoridated toothpaste, professional prophylaxis every 2 months with topical application of fluoride gel and reinforced motivation. The oral hygiene level was measured using the Silness-Löe plaque index and caries were recorded using the def and DMF surface indices, including incipient lesions. The 3-yr results showed a significant 52% plaque reduction in the test group compared with the control group. Caries reduction was significant at the 0.01% level: 44% for primary teeth and 60% for permanent teeth.