噛みしめ型FKO適用状況と効果の検討 Examination in Regard to the Applied Status and Effects on the Biting Type FKO
The aims of this study were to examine the applied status of a biting type FKO (B-FKO) which is a modified Andersen type FKO and to re-examine its effects. The B-FKO was applied with the object of promoting the mandibular growth toward the mesial direction by clenching at the molar segment. The subjects consisted of 21 patients, aged 8-12.3 years,9.8 years on average, all of whom possessed an large over jet (deep bite and protrusion) and to whom the B-FKO had been applied. Numerous parameters such as cephalometric analysis, study casts and treatment record were assessed at the onset of the treatment using the B-FKO, at the removal and 1 year after the removal to determine treatment-related changes due to therapy with the B-FKO.<BR>According to the treatment record, the two objects for employing this appliance were to promote the mandibular growth (PG) and to reduce the over jet or bite. The former has a frequency of 61.9%and with skeletal factors taken from roentgenographic cephalometry while the later has a frequency of 38.1% with the dento-alveolar factor. The appliance has been used during the beginning of a mixed dentition. Attitude on the part of the patients when using the appliance was demonstrated as an important factor which have the benefits on the therapy. Among the changes in the skeletal profile from the onset of the B-FKO to its removal, as for the deference between the onset and the removal ∠ANB, over jet, and ∠LsN′Li decreased significantly. The indications in the skeletal profile at the removal showed however mandibular retrusion still in the subjects alone with the expected effects. The judgment of the effects was made based on changes in the soft tissue profile following therapy. Among the changes in the skeletal profile from the removal of the B-FKO to 1 year after the removal, the diffbrence between the removal and the 1 year after the removal as for ∠LsN′Li increased significantly again. Among the qualitative changes from the onset to 1 year after a time of the removal, ∠SNB, Go-Me, ∠A′N′B′, and ∠LsN′Li demonstrated the tendency to retum.<BR>These findings indicated that the B-FKO was a useful appliance for changing the skeletal profile. The effect was not enough however to improve and to be stable. Moreover, it was suggested that the skeletal profile changes during B-FKO therapy were often not maintained thereafter.
小児歯科学雑誌 36(4), 595-603, 1998-09-25
The Japanese Society of Pediatric Dentistry