Title	An Upright Maxillary Lateral Incisor Inclination May Predict Palatal Displacement of Maxillary Canine
Clinical Question	In patients with a palatal maxillary canine displacement, is the inclination of the maxillary lateral incisors a significant diagnostic tool for canine eruption?
Clinical Bottom Line	There appears to be an association between the presence of more upright maxillary lateral incisors and palatally displaced canines.
Best Evidence
PubMed ID Author / Year Patient Group Study type (level of evidence) 23631964 Liuk/2013 Experimental group: 40 patients with 46 displaced maxillary canines Control group: 30 patients with 60 non-displaced maxillary canines Case Control Study Key results In the results of a multiple regression analysis, the investigators determined that the differences between the two patient groups were significant for both canine variables (P<0.001) and lateral incisor variables (P<0.005). The most significant variables were the angulations of the maxillary lateral incisors both sagittally (P<0.005, mean 17.7°) and coronally (P<0.001, mean 9.8°), where the lateral incisors tended to be more upright in both planes for the group with palatally displaced canines.
Evidence Search	displaced[All Fields] AND ("cuspid"[MeSH Terms] OR "cuspid"[All Fields]) AND ("maxilla"[MeSH Terms] OR "maxilla"[All Fields] OR "maxillary"[All Fields]) AND lateral[All Fields] AND ("incisor"[MeSH Terms] OR "incisor"[All Fields] OR "incisors"[All Fields])
Comments on The Evidence	Validity: The gold standard to date for determining displacement of the maxillary canines is considered to be whether or not the maxillary canine cusp tip extends to the mesial of a line that bisects the maxillary lateral incisor mesiodistally. This article did not specifically test against the gold standard, but instead compared the orientation and dimension of the maxillary incisors with the orientation and location of the displaced canines. The experimental group was sex- and age-matched with the control group to prevent confounding; however, tomograph collection, patient recruitment, and data extraction were not standardized. Sufficient measurements of digital cone-beam volumetric tomography images were taken by one non-blinded investigator and analyzed to account for variations in the morphology, location, and orientation of the maxillary lateral incisors and canines. No competing interests were disclosed. Perspective: Based on this case control study, determining the inclination of the maxillary lateral incisors may be a potential tool for predicting maxillary canine displacement. However, since a case control study is cross-sectional in nature, more evidence is necessary to confirm the association and usefulness of such an association. Thus, a longitudinal study that follow patients with nonerupted canines would be beneficial in determining whether patients who have more upright maxillary lateral incisors initially are more likely to have palatally displaced canines upon eruption.
Applicability	Because the permanent maxillary lateral incisor generally erupts before the permanent maxillary canine, observing the angulation of the lateral incisor may be an early beneficial diagnostic tool to determine whether a patient’s maxillary canine may become palatally displaced. Measures could then be taken to prevent canine displacement, thus potentially eliminating the later need for patients to need surgery to retrieve the displaced tooth.
Specialty	(General Dentistry) (Orthodontics)
Keywords	Displaced tooth Cone-Beam Computed Tomography Cuspid/anatomy Cuspid/radiography Incisor/anatomy Incisor/radiography Maxilla Palate, Hard Tooth Eruption, Ectopic
ID#	2998
Date of submission	03/07/2016
E-mail	mitchellaj@livemail.uthscsa.edu
Author	Amanda Mitchell
Co-author(s)
Co-author(s) e-mail
Faculty mentor	Clarence C. Bryk, DDS, MS
Faculty mentor e-mail	brykc@uthscsa.edu
Basic Science Rationale (Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?) None available
Comments and Evidence-Based Updates on the CAT (FOR PRACTICING DENTISTS', FACULTY, RESIDENTS and/or STUDENTS COMMENTS ON PUBLISHED CATs) None available