J. Ghosh et Rs. Nanda, EVALUATION OF AN INTRAORAL MAXILLARY MOLAR DISTALIZATION TECHNIQUE, American journal of orthodontics and dentofacial orthopedics, 110(6), 1996, pp. 639-646
The purpose of this study was to determine the effects of the pendulum
appliance on distalization of maxillary molars and the reciprocal eff
ects on the anchor premolars and maxillary incisors. Initial and follo
w-up cephalometric radiographs were obtained on 41 subjects (26 girls
and 15 boys) who were treated with the pendulum appliance for bilatera
l distalization of the maxillary first molar teeth, for correction of
the Class II molar relationship or for gaining space in the maxillary
arch. Dental casts were available on 31 patients, Dental, skeletal, an
d soft tissue changes were determined. The mean maxillary first molar
distalization was 3.37 mm, with a distal tipping of 8.36 degrees, The
mean reciprocal mesial movement of the first premolar was 2.55 mm, wit
h a mesial tipping of 1.29 degrees. The maxillary first molar position
intruded 0.1 mm, whereas the first premolar extruded 1.7 mm. The tran
sverse width between the mesiobuccal cusps of the first molars increas
ed 1.40 mm. The maxillary second molars were also distalized 2.27 mm,
tipped distally 11.99 degrees, and moved buccally 2.33 mm. The effect
of distalization on the maxillary third molars was extremely variable,
The eruption of maxillary second molars had minimal effect on distali
zation of first molars. The lower anterior face height increased by 2.
79 mm. This increase was greater in patients with higher Frankfort-man
dibular plane angle measurements, The pendulum appliance is an effecti
ve and reliable method for distalizing maxillary molars, provided the
anchor unit is adequately reinforced, Its major advantages are minimal
dependence on patient compliance, ease of fabrication, one-time activ
ation, adjustment of the springs if necessary to correct minor transve
rse and vertical molar positions, and patient-acceptance.