After consulting with my vet, it turns out that the efficiency of this product is proven but the emphasis is not put on enough precautions. !!!! This product contains XYLITOL which is a natural substance derived drank birch. If Xylitol is absolutely not dangerous to humans, in contrast to the dog, it can be fatal or cause for serious illness (hypoglycemia, liver disease, kidney ....) if ingested in too large quantity. That is why it is imperative to respect the dosage stated on the bottle and never overdose. Especially if one keeps dogs of very small sizes. However, the effectiveness remains real and superior to all other products "pipo" sold in large area such bones to gnaw or other bar supposedly descaling!