Association of canine impaction with morphological features of maxillary structures- a retrospective cross sectional observational study using CBCT.

The prevalence of canine impaction has been reported to be 1%-4% in different geographic and ethnic populations, this being  higher in patients reporting for orthodontic treatment than estimated for general public, thus validating its influence on malocclusion, esthetics and function. The importance of canine in smile anatomy and physiology is ever established, not only due to the insertion of zygomaticus major, which is one of the important muscles during smiling and also its position at the corner while smiling.  The canine to canine width not only holds the symmetrical smile line but also determines the smile arch.  To a beholder the canines are as important in smile as lateral incisor and central incisor. Thus absence of the canine, which could be due to agenesis ,extraction or impaction, leads to a disharmony not only in smile esthetics but also in masticatory function and may also lead to TMJ dysfunction due to loss of canine protected occlusion.

Thus diagnosing and treating an impacted canine has always been an enigma to the Radiologist as well as an Orthodontist, which needs an interdisciplinary approach to effecting a near perfect or ideal treatment.  The team may consist of orthodontist, radiologist, oral surgeon, pedodontist, periodontist and even endodontist and prosthodontist depending on the severity and complications of the case involved, the obsession with canine and its management for orthodontist is engrained so as to never lose an impacted canine. Multiple methods have been used for diagnosing an impacted maxillary canine such as inspection, palpation and radiographs.  Radiography has time and again been used with intra oral and extra oral techniques to locate the impacted canine in maxilla.  periapical and occlusal films (intraoral) and lateral and frontal cephalograms, OPG, and CT images(extra oral techniques)have also been used. Timely prediction and intervention of canine impaction has a probability of better prognosis

Though OPG (panoramic view) has been an invaluable tool to determine the position of impacted tooth in the jaw bones but as it has its limitations in determining the buccal and palatal position of the offending tooth as well as the related root resorption of the adjacent tooth which, is difficult to identify. CBCT imaging while on the other hand has the advantage of being more accurate, reliable and of high resolution.  Thus in the present study it was attempted through any associated anatomical and morphological differences, when studied in cases of unilateral maxillary canine impaction, to predict their association with the  said anomaly using CBCT imaging.

Materials and methods: CBCT images of patients with unilateral maxillary canine impactions will be selected retrospectively from the collection of radiographic images of patients treated at the study site.

Each of the scans meeting the inclusion criteria will be studied and observations will be recorded by an experienced Oral radiologist.

Statistics: the data obtained will be analyzed with statistical tests.