In the group treated with Forsus FRD appliances, the upper incisor teeth proclined and protruded, while the Jasper Jumper appliance had a retroclination
and retrusion effect.
[13,16] Previous studies showed that gingival recessions damage to the root surface and the alveolar bone might occur with the proclination or retroclination
of the mandibular incisors also.
However, agenesis, microdontia and tooth impaction have been associated with Class II division 1 in Portuguese patients, showing correlation with retroclination
of four or more maxillary anterior teeth.12
Class II malocclusion characterized by proclination of the maxilla and/or upper dental arch or retroclination
of the mandible and/or lower dental arch or combination of these is a type of malocclusion in which accurate diagnosis and appropriate treatment can yield successful outcomes (1).
Intraorally, the retroclination
of upper and lower incisors was corrected.
Treatment with both appliances resulted in significant increase of the SNB angle, reduction of the ANB angle, retrusion and retroclination
of the maxillary incisors, protrusion and proclination of the mandibular incisors, and reduction of the OJ (Table 3).
The lower lip line is slightly resting higher than normal which resulted in the retroclination
of the upper central incisors.
This strongly indicates that the change in the above dimensions in the mandibular arch is due to retroclination
of mandibular incisors rather than true deficiency in the arch itself.
Solow et al47 showed that obstructed nasopharyngeal airways are usually seen in connection with a large craniocervical angle, a small mandibular dimensions, mandibular retrognathism, a large mandibular inclination, and retroclination
of the upper incisors.
On cephalometric evaluation, an ANB of 8[degrees] (SNA: 82[degrees], SNB: 74[degrees]) was measured, skeletal class II malocclusion due to mandibular retrognathia was detected, and retroclination
of the maxillary incisors (U1-SN: 83[degrees], U1-PP: 89[degrees]) and slight proclination of the mandibular incisors (IMPA: 94[degrees]) were observed.
In fact, the patient's initial occlusion showed a remarkable dental compensation to the skeletal pattern characterized by high proclination of the lower incisors and retroclination
of the upper incisal group.