[Open bite and interdental sigmatism].

The authors revealed very often open bite in preschool children with interdental sigmatism and vice versa. They investigated the effect of interdental sigmatism on the persistence of open bite. According to the authors findings open bite persists in 3-5 year-old children with open bite and interdental sigmatism after a 10-to-22 month follow-up significantly more often than in children of similar age with open bite but without interdental sigmatism. Interdental sigmatism is associated with already existing open bite. It is possible that at the time of their development open bite and interdental sigmatism have no causal relationship and the two defects associate accidentally. Only during subsequent development open bite persists more frequently in those children who suffer at the same time from interdental sigmatism, while in children without interdental sigmatism the open bite improves more often.