Percentiles relative to maxillary permanent canine inclination by age: a radiologic study.
BACKGROUND
Few studies have investigated developmental norms for maxillary permanent canine eruption. In this observational cross-sectional study, we aimed to provide an age-related description of the percentiles relative to canine inclination in a large sample of nonorthodontic patients. Associations between inclination and sector were also analyzed.


METHODS
Canine inclination and sector location were measured on 1020 panoramic radiographs obtained from subjects of white ancestry aged between 8 and 11 years not seeking orthodontic treatment. The total sample comprised 2037 canines.


RESULTS
Canine inclination increases between 8 and 9 years and decreases between 9 and 11 years. The greatest value for each percentile is at 9 years. A linear model should be hypothesized for differences in canine inclination between 2 successive ages in correspondence to each percentile. The proportion of sector 2 canines decreases and that of sector 1 increases with age. In the same age group, the inclination generally decreases as the sector decreases.


CONCLUSIONS
Percentiles by age show the average canine inclination in a certain population. Further studies are required to verify whether percentiles can be a diagnostic aid for determining normal canine inclination at a given age and for quantifying the risk of canine impaction or adjacent root resorption.
Alessandri Bonetti
Giulio
G
Department of Orthodontics, Alma Mater Studiorum University of Bologna, Bologna, Italy. giulio.alessandri@unibo.it
Zanarini
Matteo
M
Danesi
Margherita
M
Parenti
Serena Incerti
SI
Gatto
Maria Rosaria
MR
D000367:Age Factors; D002648:Child; D003430:Cross-Sectional Studies; D003481:Cuspid / Q000000981:diagnostic imaging / Q000502:physiology*; D003724:Dental Arch / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D005260:Female; D005544:Forecasting; D006801:Humans; D008297:Male; D008437:Maxilla / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D009811:Odontometry / Q000379:methods; D011862:Radiography, Panoramic; D012307:Risk Factors; D014078:Tooth Eruption / Q000502:physiology*; D014095:Tooth, Impacted / Q000000981:diagnostic imaging; D014097:Tooth, Unerupted / Q000000981:diagnostic imaging