Maxillary dimensions and arch shape with palatally displaced canines

Abstract

Summary Background/objectives The aim of this study was to explore the effect of palatally displaced canines on maxillary dimensions and arch shape. Methods Occlusal and skeletal landmarks were plotted on cone beam computed tomography (CBCT) images of 156 orthodontic patients: 78 with palatally displaced canines (PDC) (27 left, 28 right, and 23 bilateral) and 78 controls using Mimics™ (Materialise, Belgium). Arch forms were created, and arch width, depth, and skeletal dimensions were measured. T-test (P < 0.05) was used to compare the groups. Geometric Morphometrics (GM) analysis was used to compare the groups and to explore the pattern of covariation between two sets of landmarks. Results The unilateral PDC group showed an increased first premolar, second premolar, molar widths, and an increased molar depth. No significant difference was found in arch form. The skeletal measurements were generally larger in the PDC group, but the transverse measurements were the most significant. Discriminant Function Analysis (DFA) with cross-validation allowed an accurate classification of 85.9% of the control group and 66.7% of the PDC group. The Mahalanobis distance displayed significant differences among three combinations of groups. Strong covariance was found between the second premolar and all other landmarks. Limitations The small sample sizes of the stratified groups precluded recognition of statistical significance. Conclusions Patients with unilateral PDC displayed significantly wider first, second premolar, and first molar widths, and increased first molar depths. There were no significant differences in arch form; however, GM showed significant differences between the groups and a prominent covariance function for the 2nd premolars.

Statistical shape analysis of maxillary palatal morphology in patients with palatally displaced canines

“…Discriminant analysis also showed an accurate classification of 85.9% for the control group and 66.7% for the PDC group. In the present study, prediction accuracy was 70% for the control group and 68.9% for the PDC [ 29 ].…”

Skeletal and dental maxillary morphological characteristics in patients with impacted canines: systematic review and meta-analysis

“…The appropriate timing of the maxillary arch expansion procedure could resolve the transverse deficiency and lower the risk of canine impaction [ 28 ]. In contrast, Saade et al [ 29 ] found wider first molar and premolar widths in patients with palatally displaced canines. This might be due to the different methodologies applied.…”

Cephalometric characteristics of patients with vestibular and palatal canine impaction

“…Smatra se da se etiopatogeneza bukalnih (BI) i palatinalnih impakcija (PI) očnjaka suštinski razlikuje 6,7 . Bukalno impaktirani očnjaci češće se povezuju sa nedostatkom prostora u gornjoj vilici, sagitalnom i transveralnom nerazvijenošću maksile, teskobom i uskom apikalnom bazom 8 ; veći broj palatinalno impaktiranih očnjaka uočen je pak kod pacijenata sa dobro razvijenom gornjom vilicom, prerazvijenom apikalnom bazom, te pacijenata kod kojih nije prisutna teskobnost zubnih nizova 7,9,10 . Cilj rada bio je ispitati i analizirati kefalometrijske karakteristike pacijenata sa impaktiranim stalnim očnjakom.…”

“…Ukoliko se rizik od impakcije prepozna u ranoj fazi, primena interceptivnih mera, poput ekstrakcije mlečnog očnjaka 16,17 i upotrebe aparata za rapidnu ekspanziju palatuma 18 , može umnogome doprineti nicanju ovih zuba. Mnogi autori su pokušavali da ispitivanjem i analiziranjem dentoskeletnih karakteristika predvide rizik od nastanka impakcije maksilarnog očnjaka 1,6,8,19,20 . Kada je reč o sagitalnim parametarima, analiza ANB ugla sprovedena u okviru ove studije ukazala je na najveću zastupljenost impaktiranog očnjaka u grupi pacijenata II klase po Angleu (44,3%), dok je najmanji broj ispitanika u grupi pacijenata III klase po Angleu (25,7%).…”

“…Many factors are directly associated with the occurrence of this irregularity and it is considered that the etiopathogenesis of buccal impaction (BI) and palatal impaction (PI) of canines is essentially different 6,7 . Buccally impacted canines are more often associated with a lack of space in the upper jaw, sagittal and transverse underdevelopment of the maxilla, tightness, and a narrow apical base 8 , whereas a greater number of palatally impacted canines is observed in patients with a well-developed upper jaw, an overdeveloped apical base, and no tight dental rows 7,9,10 .…”