The influence of malocclusion on the diagnostic value of the orthopantomogram in the maxillary labial segment.
OBJECTIVE
To investigate the effect of malocclusion and incisor inclination on the diagnostic value of the orthopantomogram in the maxillary labial segment.


METHODS
The Department of Orthodontics at The Royal London Hospital.


METHODS
A literature review identified seven key features of an ideal radiograph of the upper labial segment. This provided the 'Gold Standard'. Four previously extracted maxillary incisors were set-up with a complementary acrylic dentition in a dry human skull. The maxillary base was modified to facilitate the movement of the upper jaw to simulate a total of nine malocclusions, based on skeletal I, II with III patterns with varying upper incisor inclination. A lateral cephalogram was taken to quantify the upper incisor inclination. An orthopantomogram (OPG), upper standard occlusal (USO) and four long-cone periapical radiographs (PA) were also taken. Each radiograph was scored against the Gold Standard. In addition, a clinical audit involving 100 new orthodontic patients was carried out to determine whether in vivo findings mirrored the in vitro results.


RESULTS
The orthopantomogram provides low levels of diagnostic value in the maxillary incisor region. The diagnostic value for the skeletal I skull set-up ranged from 57 per cent for the OPG, 71 per cent for the USO and 86 per cent for the PA view.


CONCLUSIONS
The orthopantomogram showed poor diagnostic value in relation to the upper incisor teeth. Long-cone periapicals are recommended as the supplementary view of choice in the maxillary incisor region.
Oral Growth and Development, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
M L
ML
Hayes
A
A
Johal
D002508:Cephalometry / Q000592:standards; D019230:Dental Audit; D006801:Humans; D007180:Incisor / Q000000981:diagnostic imaging*; D008310:Malocclusion / Q000000981:diagnostic imaging*; D008311:Malocclusion, Angle Class I / Q000000981:diagnostic imaging; D008312:Malocclusion, Angle Class II / Q000000981:diagnostic imaging; D008313:Malocclusion, Angle Class III / Q000000981:diagnostic imaging; D008437:Maxilla / Q000000981:diagnostic imaging*; D008953:Models, Anatomic; D057887:Overbite / Q000000981:diagnostic imaging; D011446:Prospective Studies; D016300:Radiography, Bitewing / Q000592:standards; D011862:Radiography, Panoramic / Q000592:standards*; D019227:Tooth Apex / Q000000981:diagnostic imaging