During the last 15 years, cleft lip and palate (CLP) patients with maxillary deficiency in the care of the Bergen CLP team have undergone an interceptive orthopedic treatment phase during the deciduous and mixed dentition period. The present study includes 68 patients who received maxillary transverse expansion by use of a modified quad-helix appliance and 98 cases given maxillary protraction by a facial mask. All cases were treated until an acceptable normal occlusion was attained. Lateral cephalograms were taken immediately before and after the active treatment periods. Sagittal changes of the soft-tissue profile during transverse expansion and protraction were analyzed separately for unilateral complete cleft lip and palate (UCLP) patients and bilateral complete cleft lip and palate (BCLP) patients. The soft-tissue profiles of the groups were compared to growth changes of noncleft age-matched children (NORM group). During the short period of maxillary transverse expansion (mean period, 3.5 months) no significant change of the soft-tissue profile was found, except in the protrusion of the lower lip in the BCLP group. During the period of maxillary protraction (mean periods, 12 months in the UCLP group and 15 months in the BCLP group) the soft-tissue profile improved significantly by reducing the characteristic tendency towards a concave profile in CLP patients with maxillary deficiency. Significant Increases of the sagittal maxillomandlbular lip relation (angle SS-N-SM: mean Increase, 2.5 degrees) and the Holdaway-angle (H-angle: mean increase, 3.0 degrees) were found to be similar in the UCLP and BCLP groups. However, the use of different reference lines for evaluation of treatment effects upon the soft-tissue profile resulted in conflicting findings suggesting that anteriorly situated reference lines are more suitable for the evaluation of CLP patients. Thus, the esthetic line (E.line) indicated a favorable position of the lips after treatment; the subspinale-pogonlon line (ss.pg) revealed an Improved soft-tissue profile; the soft-tissue-facial line (N.PG) showed a retruded nose and upper lip; whereas basal references such as the nasion-sella line (NSL) and the occlusal-line perpendicular (OLP) mainly showed major differences between the CLP groups and the NORM groups.
Transverse expansion of the electron sheath during laser acceleration of protons
