Impacted maxillary canine: Assessment of prevalence, severity and location of root resorption on maxillary incisors: A retrospective CBCT study.

BACKGROUND: The maxillary permanent canine is one of the most frequently impacted teeth, which often requires multidisciplinary management. A common complication of canine impaction is root resorption of the adjacent dentition. The aim of this retrospective study was to report the prevalence of root resorption of maxillary incisors adjacent to impacted maxillary canines from small volume CBCT images by trained clinicians. A secondary objective was to report the location and severity of root resorption. MATERIAL AND METHODS: CBCT images of patients with impacted maxillary canines (unilateral and bilateral) who attended a joint orthodontic/surgical multidisciplinary clinic were screened. Descriptive statistics were used to investigate associations of patient characteristics and presence of root resorption. Generalized estimating equations (GEE) logistic regression model were used to identify predictors of root resorption. RESULTS: In all, 148 impacted maxillary canines (122 patients) were analysed. The majority of patients were under 18 years of age (71.6%) with impacted canines present in more females (68.2%) than males (31.8%). Maxillary lateral incisors showed the highest prevalence of root resorption (38.5%). The apical region was the most common location of resorption for lateral incisors (20.9%) with a variable degree of severity evident: slight (10.1%), moderate (15.6%), and severe (12.8%). Although no significant predictors of root resorption were identified, a weak association was evident for age and root development. CONCLUSIONS: In this cohort of patients, the roots of maxillary lateral incisors are most likely to suffer from root resorption in the presence of an impacted maxillary canine. Clinicians should consider the extent, location and severity of resorption of adjacent teeth when planning treatment decisions and mechanics in cases of impacted maxillary canines.

Long-term follow-up after the treatment of impacted canines in the maxilla causing severe root resorption of the lateral incisors: two case reports.

BACKGROUND: Root resorption of adjacent teeth due to impacted canines is common, and orthodontic treatment often leads to secondary resorption or even loss of adjacent roots. Clinical reports of long-term stability after treatment are rare. CASE PRESENTATION: This study reports two cases of maxillary impacted canines resulting in severe root resorption of the adjacent lateral incisors. Surgical exposure, orthodontic retraction, and alignment of the impacted canines were successful in both cases, and the resorbed lateral incisors were stable with no significant loosening and normal pulp vitality after treatment and at the 5- and 10-year follow-up appointments. CONCLUSIONS: Light orthodontic force may be used to move adjacent teeth with root resorption due to tooth obstruction. The path and direction in which the teeth are moved must be specifically designed so that the adjacent roots are not resorbed and so long-term stability can be achieved.

Accuracy of CBCT in Preoperative Assessment of Impacted Canines vs. Panoramic Radiography.

Background: Accurate assessment of impacted canines is crucial for successful treatment planning. Radiographic techniques like Cone Beam Computed Tomography (CBCT) and Panoramic Radiography are commonly used, but their comparative accuracy remains under scrutiny. Materials and Methods: In this study, 50 patients diagnosed with impacted canines were enrolled. Both CBCT and Panoramic Radiography images were obtained for each patient using standard protocols. Two experienced dentists independently analyzed the images to determine the position of impacted canines and their relationship with neighboring structures. Results: The findings of this study revealed that CBCT provided superior accuracy in assessing the position of impacted canines compared to Panoramic Radiography. Specifically, CBCT demonstrated a mean accuracy rate of 89.5%, while Panoramic Radiography showed a mean accuracy rate of 72.3%. Moreover, CBCT allowed for better visualization of impacted canine angulation, depth, and spatial orientation. Panoramic Radiography, on the other hand, displayed limitations in precisely identifying the impacted canine's position. Conclusion: The study's outcomes underscore the higher accuracy of CBCT over Panoramic Radiography in the preoperative assessment of impacted canines. CBCT's detailed imaging provides valuable insights for treatment planning, potentially leading to improved surgical outcomes. Although CBCT entails greater radiation exposure and cost, its benefits in accurate diagnosis and treatment planning justify its use in cases of impacted canines.

Artificial Intelligence for 3D Reconstruction from 2D Panoramic X-rays to Assess Maxillary Impacted Canines.

The objective of this study was to explore the feasibility of current 3D reconstruction in assessing the position of maxillary impacted canines from 2D panoramic X-rays. A dataset was created using pre-treatment CBCT data from a total of 123 patients, comprising 74 patients with impacted canines and 49 patients without impacted canines. From all 74 subjects, we generated a dataset containing paired 2D panoramic X-rays and pseudo-3D images. This pseudo-3D image contained information about the location of the impacted canine in the buccal/lingual, mesial/distal, and apical/coronal positions. These data were utilized to train a deep-learning reconstruction algorithm, a generative AI. The location of the crown of the maxillary impacted canine was determined based on the output of the algorithm. The reconstruction was evaluated using the structure similarity index measure (SSIM) as a metric to indicate the quality of the reconstruction. The prediction of the impacted canine's location was assessed in both the mesiodistal and buccolingual directions. The reconstruction algorithm predicts the position of the impacted canine in the buccal, middle, or lingual position with 41% accuracy, while the mesial and distal positions are predicted with 55% accuracy. The mean SSIM for the output is 0.71, with a range of 0.63 to 0.84. Our study represents the first application of AI reconstruction output for multidisciplinary care involving orthodontists, periodontists, and maxillofacial surgeons in diagnosing and treating maxillary impacted canines. Further development of deep-learning algorithms is necessary to enhance the robustness of dental reconstruction applications.

Apical incisor root resorption due to ectopic maxillary canine eruption: Association with time of diagnosis and type of intervention in a retrospective population-based cohort study.

OBJECTIVES: The primary aim was to study upper incisor severe apical root resorption (RR) related to ectopic canine eruption and its association with timing of diagnosis and type of intervention conducted. The secondary aim was to correlate resorption with other dental anomalies. MATERIALS AND METHODS: Digital journals and radiographic material of all ectopic maxillary canines registered in 2012 in the regional public paediatric dental clinics in the Council of Aarhus were inspected retrospectively. Data related to 10 variables were retrieved. Post-treatment radiographs were used for evaluation of incisor RR. RESULTS: A total of 260 ectopic maxillary canines were diagnosed in 2012. The majority were found in the 9-13-year-old age group (0.8% prevalence within the total population). In all, 244 canines were assessed for eligibility and 181 had adequate final radiographs for evaluation of RR. Among ectopic maxillary canines, 9.4% caused severe incisor RR to neighbouring teeth. Timely palpation for canine eruption significantly reduced the odds for upper incisor resorption by 80%. Multiple regression showed that when the permanent canine cannot be palpated and the deciduous has been extracted, delaying the first X-rays was associated with a 38% odds ratio increase for RR for each year of delay after the age of 10 years. No significant associations were found between incisor RR and intervention conducted or other dental anomalies. CONCLUSION: Palpation of erupting maxillary canines is crucial for timely diagnosis of ectopic eruption and initiation of treatment to avoid RR. If the canine cannot be palpated at 10 years of age, radiographic examination is highly recommendable.

Radiographic assessment of unerupted permanent maxillary canines and their relationship to the phases of dentition in mixed dentition Spanish children: a retrospective cross-sectional study.

PURPOSE: Evaluate if there is a significant association between the position and inclination of the unerupted maxillary canine measured on a panoramic radiograph, and their relationship to gender, age of the patient and stage of dentition. METHODS: 138 panoramic radiographs were examined for this retrospective cross-sectional investigation. Only patients living in Madrid, Spain with mixed dentition were included. These measurements were performed on radiographs, considering the inclination and position of the maxillary canines with regards to the midline, and height with respect to the occlusal plane. Spearman's correlation coefficient was used to analyze the relation among the canine angle and height. p < 0.05 was considered to be significant. RESULTS: The prevalence of patients with an altered canine angle was 10%, while 43.5% had an apparently abnormal position (overlapping at least half of the adjacent lateral incisor root). No statistically significant association was found between these two variables. In 5% of the patients, the maxillary canine was with an anomalous angle and position. Significant differences were obtained when comparing canine height between children with ectopic canines and normal canines (p = 0.032). CONCLUSION: No significant association was found between the position and inclination of the unerupted maxillary canine in our sample. Ectopic maxillary canines had a higher incidence in girls, although we did not find statistically significant differences between genders. We observed a higher prevalence of abnormal position and inclination of the permanent maxillary canine in early mixed dentition. Maxillary canines were significantly elevated, further from the occlusal plane, in children with ectopic canines.

Orthodontic Treatment of Palatally Impacted Maxillary Canines with the Use of a Digitally Designed and 3D-Printed Metal Device.

The purpose of this article is to present a computer designed and 3D-printed metal device, which was used for the surgical exposure and orthodontic treatment of maxillary palatally impacted canines. In two cases which presented a palatally impacted canine, a Cone-Beam Computed Tomography (CBCT) was acquired and an intraoral scanning was performed, to determine the exact location of the canine. Based on a digital model, a device leaning on the teeth and mucosa was designed to serve as a guiding tool for the oral surgeon to expose the crown of the canine and help the orthodontist to provide proper traction. The device was then 3D-printed in biocompatible dental alloy and placed in the patients' mouth. After the surgical exposure of the canine's crown in both cases, a gold chain apparatus was bonded on and it was mounted on the metal projection of the device through an elastic chain. Within 3 months of traction, the crown of the canines appeared in the patients' palate to the exact location that was predicted and guided. A 3D-designed and manufactured metal device, with information acquired by CBCT and intraoral scanning, can be used for the exposure and traction of palatally impacted canines.

Success rate, treatment duration, and pain perception in the management of palatally impacted canines using the K9 and Ballista spring: a randomized clinical trial.

OBJECTIVES: To evaluate the success rate, treatment duration, and pain perceived during forced eruption of maxillary palatally impacted canines using the K9 and Ballista springs. MATERIALS AND METHODS: Thirty unilateral palatal canine impactions of moderate and difficult category as determined by KPG index (score between 10 and 19) were enrolled. Group 1 comprised canine impactions managed with K9 springs, and Group 2 comprised Ballista springs. Block randomization and opaque sealed envelopes were used for allocation. The success rate and treatment duration (application of force to ligation of the impacted canine into the initial alignment archwire) were recorded. Pain perception was evaluated on a 10-point visual analogue scale (VAS) and modified McGill Pain Questionnaire. Chi-square test and Mann-Whitney U-test were used to compare the groups. RESULTS: The success rate for eruption of palatally impacted canines was 100%. The average treatment duration was 296.13 ± 96.45 days and 311.93 ± 94.34 days, respectively for Group 1 and Group 2. VAS scale scores for pain were greater for Group 2 compared to Group1, and the differences were statistically significant at all time intervals except at T1. The frequency of none and mild pain was significantly greater at all time intervals in both groups. CONCLUSIONS: The impacted canines of moderate and difficult category were erupted with a 100% success rate and similar treatment duration with both interventions. The pain scores of Ballista springs were greater after 24 hours of force application.

Periodontal health of unilateral labially vs. palatally impacted maxillary canines erupted by closed eruption technique.

OBJECTIVE: This study's aim was to compare the periodontal health of labially and palatally impacted maxillary canines erupted by closed eruption technique, and to compare them with the contralateral canines that served as control teeth. MATERIALS AND METHODS: A total of 32 subjects, 17 with unilateral labially impacted maxillary canines and 15 with palatally impacted maxillary canines were enrolled in this study. Pretreatment maxillary canine variables were evaluated from initial panoramic radiographs using Nolla stage, α­angle, d­depth and s­sector. The closed eruption technique was used for surgical exposure of the impacted teeth. Posttreatment periodontal parameters such as plaque index (PI), gingival index (GI), gingival bleeding index (GBI), probing depth (PD), keratinized gingival width (KGW), attached gingival width (AGW), and gingival thickness (GT) were evaluated to compare the periodontal health with the contralateral canines. RESULTS: Intergroup comparison results exhibited insignificant differences in all periodontal parameters between the labially and palatally impacted maxillary canines. Intragroup comparison results showed a significant increase in PI, GI, GBI, and PD, and a significant decrease in AGW, KGW, and GT in the impacted teeth compared to the controls, except for PI in the palatally impacted maxillary canines. CONCLUSION: The decrease in KGW, AGW, and GT was not associated with the pre-eruptive position of the impacted teeth. These side effects seen after orthodontic treatment of impacted teeth should be followed carefully in the long term.

Orthodontic Localization of Impacted Canines: Review of the Cutting-edge Evidence in Diagnosis and Treatment Planning Based on 3D CBCT Images.

A thorough clinical and radiographical assessment of an impacted maxillary canine's location forms the basis for proper diagnosis and successful treatment outcomes. Implementing a correct biomechanical approach for directing force application primarily relies on its precise localization. Poor biomechanical planning can resorb the roots of adjacent teeth and result in poor periodontal outcomes of the canine that has been disimpacted. Furthermore, treatment success and time strongly rely on an accurate assessment of the severity of impaction, which depends on its 3D spatial location. The evolution of cone-beam computed tomography (CBCT) radiographs provides more detailed information regarding the location of the impacted canines. In addition, the literature has shown that CBCT imaging has enhanced the quality of diagnosis and treatment planning by obtaining a more precise localization of impacted canines. This review article highlights current evidence regarding comprehensive evaluation of three-dimensional orientations of impacted canines on CBCT images for precise diagnosis and treatment planning.

Evaluation of Lateral Incisor Resorption Caused by Impacted Maxillary Canines Based on CBCT: A Systematic Review and Meta-Analysis.

BACKGROUND: Root resorption (RR) of the adjacent teeth due to upper canine impaction requires an appropriate modification of the orthodontic treatment plan and the mechanotherapy used. AIM: The aim of this review was to assess scientific evidence published during the last decade, concerning the prevalence of lateral incisor RR caused by impacted maxillary canines, based only on cone-beam computed tomography (CBCT). The location of RR on this tooth, as well as the prevalence of RR on the other adjacent teeth, were additionally evaluated. METHODS: This review followed the criteria specified by the PRISMA statement. Four databases were searched for articles published between January 2008 and June 2021. Predefined and piloted data collection forms were used to record the necessary information. RESULTS: A total of 5098 records were initially screened. Only seven articles were finally eligible for further analysis. A total number of 540 participants (176 males and 364 females) was derived from the included studies. RR of maxillary lateral incisors was common (50%). RR of mild severity was more common (62%), more frequently located in the middle (52%) and apical (42%) thirds of the root. CONCLUSIONS: Further research with more homogeneous groups is required.

The diagnostic value of orthopantomograms in detecting resorption of lateral incisors associated with ectopic canines: a CBCT study.

OBJECTIVE: To examine the diagnostic value of orthopantomograms (OPG) in the identification of root resorption of lateral incisors, secondary to an impacted canine, as confirmed by a cone-beam computed tomography (CBCT) scan. DESIGN: Retrospective observational cohort study. SETTING: South Wales secondary care setting: Royal Gwent Hospital, Newport and Nevill Hall Hospital, Abergavenny. METHODS: A total of 40 consecutive patients with impacted canines between January 2018 and December 2019 were selected. For each patient, one consultant orthodontist examined the OPG in isolation to detect the presence and extent of resorption of lateral incisors. The CBCT report was then studied to confirm the presence and extent of pathology. Sensitivity, specificity, accuracy, positive predictive values and negative predictive values were calculated. RESULTS: In total, 19 maxillary right canines, 18 maxillary left canines, one mandibular right canine and two mandibular left canines were examined. Impactions were more prevalent in the maxilla (92.5%) with higher predilection towards female patients (65%). There was higher prevalence of root resorption in the maxillary right quadrant (57.1%), in concordance with other studies. OPGs were found to have a sensitivity of 81.0% and a specificity of 10.5%, with an accuracy value of 47.5%. Positive and negative predictive values were found to be 50.0% and 33.3%, respectively. The extent of root resorption was incorrectly estimated from the OPG in 84% of cases. Correct estimation occurred in 16% of cases, with overestimation and underestimation occurring in equal proportion (42%). CONCLUSION: This study demonstrates the limitations of plain film radiographs and the merits of using CBCT in the accurate diagnosis of resorption of lateral incisors with an associated impacted canine. It also gives an indication into the location prevalence of resorption in a small cohort of patients. This preliminary study establishes the basis for future, larger-scale studies where outcomes can be generalisable at a population level.

Treatment of impacted canines with aligners: An alternative and viable option.

To recover impacted canines without esthetic issues, the aligners can be a resolutive tool allowing by pontics the camouflage of absent canines during orthodontic treatment. Knowledge of biomechanics, correct staging of dental movements, and surgery planification are strategic to achieve a good result.

Orthodontic Treatment of a Patient with Dentin Dysplasia Type I and Bilateral Maxillary Canine Impaction: Case Presentation and a Family-Based Genetic Analysis.

Dentin dysplasia is a rare hereditary disorder, transmitted by autosomal dominant mode, affecting both dentin and pulp. In Type I crown morphology is normal, but root dentin organization loss leads to shorter roots. Mutations in the SSUH2, VPS4B and SMOC2 genes have been reported as responsible for this condition. Orthodontic treatment was conducted on an 11-year-old female patient presenting the disorder along with bilaterally impacted permanent maxillary canines, in close proximity to the roots of the lateral and central incisors. Treatment plan included lateral incisors extraction, surgical exposure and traction of the impacted canines. Light forces were applied from a custom-made trans-palatal arch. Comprehensive orthodontic treatment was performed using edgewise appliances. After 3 years and 2 months, group function occlusion was achieved. The canines underwent composite resin restorations. At one year post-retention, the dentition remained stable. Family-based genetic analysis did not reveal any mutations in the aforementioned genes pointing to further genetic heterogeneity of this disorder. As dental medicine becomes more sophisticated and personalized, the association between mutation type/function and orthodontic treatment response may provide useful therapeutic insights. The positive treatment response of the presented case could be attributed to a more "benign" mutation awaiting to be identified.

Uncovering and Autonomous Eruption of Palatally Impacted Canines-A Case Report.

The impaction of permanent maxillary canine is a common clinical occurrence, and it is observed in 2% of patients who require orthodontic treatment. This case report describes a new orthodontic-surgical approach through the use of CO2 laser, for the exposure of the palatally impacted canines. A 13-year-old female referred to our observation to make an orthodontic examination because of the maxillary primary canines' persistence in upper arch. Orthopanoramic X-ray showed impaction of both permanent maxillary canines. The family history revealed that the patient's mother had the same orthodontic problem. Cone Beam Computer Tomography (CBCT) was requested to plan the surgical-orthodontic treatment. Surgical exposure of the impacted canines was performed using a CO2 laser and subsequent periodontal pack application. No orthodontic devices were applied for impacted teeth traction on dental arch. Canines' movement was monitored at 1, 8 and 16 weeks post-surgery with photo and intraoral scanner CS3500 (CS3500®, Carestream Health, Atlanta, GA, USA). When canine crowns were completely erupted on palatal side, the alignment in the arch with indirect bonding technique was performed. Complete disimpaction of canine crowns was obtained in only four months. As reported in the literature, this case confirms that impacted canines' exposure to CO2 laser has advantages if compared with traditional surgery: no bleeding during and after the procedure, decontaminant effect on the surgical area, no suture, and a fast spontaneous eruption. Conclusions: The pre-orthodontic uncovering and autonomous eruption of palatally impacted maxillary canines provides simplified, predictable, and more aesthetic outcomes. Furthermore, a significant positive factor is that there is no need to carry out the orthodontic traction of the impacted element, undoubtedly better compliance by the patient during the next alignment phase with the fix orthodontic appliance.

Three-dimensional changes in root angulation of buccal versus palatal maxillary impacted canines after orthodontic traction: A retrospective before and after study.

INTRODUCTION: The aim of this study was to three-dimensionally compare the root angulation changes after orthodontic traction of buccally versus palatally maxillary impacted canines (MICs). MATERIAL AND METHODS: This retrospective study included patients from a private dental office of both sexes, older than 12 years, with at least one unilateral or bilateral buccal or palatal MIC, no loss of permanent teeth, with complete apical closure at the beginning of traction, and with CBCTs taken at pretreatment (T0) and after orthodontic traction (T1). The sample was divided in two groups according to their impaction site: buccal versus palatal. In all the scans, the MIC was segmented and the root angulation changes after traction were evaluated. The assessment included the sigma angle (projected on the XZ plane or coronal tomographic view), the delta angle (projected on the XY plane or axial view) and the epsilon angle (projected on the YZ plane, or sagittal view). Intragroup comparisons were performed with Wilcoxon signed-rank tests. Intergroup comparisons were performed with t-tests or Mann-Whitney U tests. Finally, the influence of MIC characteristics on the measured angles were evaluated with multiple linear regression analyses (α=0.05). RESULTS: Thirty-three patients (16 men, mean age: 20.38; 17 women, mean age 18.37) with forty-five orthodontically treated MIC (19 buccal versus 26 palatal) were finally included. The palatal MICs showed greater mediolateral uprighting than the buccal MICs, root displacement towards the midsagittal plane, as demonstrated by the sigma angle (palatal group: 37.58±15.08°; buccal group: 29.17±31.15°; P=0.164) and delta (palatal group: -76.90±26.55°; buccal group: -30.56±41.67°; P<0.001)angle changes. The buccal MICs showed greater anteroposterior uprighting, anterior root displacement, as demonstrated by the epsilon angle (palatal group: -4.63±12.37°; buccal group: -25.96±17.79°; P<0.001). CONCLUSIONS: Mediolateral and anteroposterior root angulation show significant differences after traction between buccal and palatal MICs. Palatal MICs showed greater medial root displacement while buccal MICs showed greater anterior root displacement. This condition should be considered for better planning of traction and orthodontic finishing.

A study of smile aesthetic perception among dental professionals, patients and parents towards impacted maxillary canine treatment options.

OBJECTIVE: To evaluate the smile aesthetics of the different treatment options for impacted maxillary canines as perceived by orthodontists, dentists, patients and parents. DESIGN: Cross-sectional survey. SETTING: Four rater groups were selected to complete the questionnaire consisting of an orthodontist group, a general dental practitioner group, a patient group consisting of patients aged 11-18 years who were considered to be 'Gillick competent' and a parent group consisting of parents/guardians who accompanied the patients to their orthodontic appointments. METHOD: Four digitally manipulated images were created to imitate different treatment options available for the treatment of ectopic maxillary canines including: alignment of the impacted maxillary canine; substituted premolars; retained deciduous canines; or gaps present. The images were embedded into piloted questionnaires. Each participant completing the questionnaire was asked to mark the visual analogue scale (VAS) beneath each image according to their perception of attractiveness of each image. Quantitative scoring of the perceived attractiveness of the smile was assessed by one calibrated assessor measuring the distance from the start of the scale to the marked cross placed on the VAS. A two-way ANOVA (mixed between-within subject's ANOVA) was used to compare perception of differences in smile aesthetics. RESULTS: There were significant differences found in the VAS between the groups (P = 0.002) and between the treatment options (P < 0.001) There was no statistically significant difference found between the aligned canines and substituted premolars images by the patient (P = 0.2) or parent group (P = 0.5). All groups most disliked the treatment option where gaps were present at the end of treatment. CONCLUSION: The patient and parent groups showed similar perception in smile aesthetics for aligned canines and substituted premolars and all groups showed a strong dislike to the presence of gaps. The orthodontist group showed the most critical aesthetic perceptions.

Three dimensional movement analysis of maxillary impacted canine using TADs: a pilot study.

BACKGROUND: The aim of the present study was to compare two different anchorage systems efficiency to disinclude impacted maxillary canines using as evaluation tool superimposed Cone Beam Computed Tomography (CBCTs). METHODS: The study has been conducted with two parallel groups with an allocation ratio of 1:1. Group test received treatment using as anchorage a miniscrew, control group was treated using an anchorage unit a trans palatal arch (TPA). Both groups received a calibrated traction force of 50 g. CBCT before treatment and 3 months after traction were superimposed and canine tip and root movement were evaluated in mm/month ratio. RESULTS: No differences were observed between groups for apex displacement, tip displacement and observation timespan. Twenty-two patients (12 female, 10 male, mean age:13.4 years) undergoing orthodontic treatment for impacted maxillary canines were recruited for this study. No differences were observed between groups for apex displacement, tip displacement and observation timespan. CONCLUSIONS: The present pilot study provided no evidence that indirect anchorage on miniscrews could make canine disimpaction faster than anchorage on a TPA. An apex root movement of 0.4-0.8 mm per month was found, while average canine tip movement ranged between 1.08 mm and 1.96 mm per month. No miniscrews failures were observed. TRIAL REGISTRATION: The study reports the preliminary results of the randomized clinical trial registered at www.register.clinicaltrials.gov (registration number: NCT01717417 ).

CBCT and Intra-Oral Scanner: The Advantages of 3D Technologies in Orthodontic Treatment.

BACKGROUND: The aim is to demonstrate the validity of the monitoring through intraoral scanner of the dental movements and the real impact, advantages, and convenience, in terms of treatment time and efficiency gain, to frequently monitor a patient with the scanner application. METHODS: A movement control of palatally impacted canines was performed, surgically treated with laser opercolectomy. Three-dimensional models of the patient's dental arch were obtained with intraoral scanner during a monitoring time of 4 months. The STL (Standard Triangle Language) files were superimposed with the 3D models extrapolated from the pre-operative CT (Computerized Tomography). The measurements of eruption, exposed palatal and vestibular areas, and distances between the canines and the incisors were performed, using digital technologies and with a digital caliber. RESULTS: Descriptive and inferential statistical analysis of the data obtained from both conventional and digital monitoring has been realized and performing the T Student Test for paired data. CONCLUSION: The advantages of digital monitoring are numerous, like the possibility to reduce the error of method caused by manual measurement on plaster casts and the possibility to compare the pattern and amount of eruption of the canine in the same patient overtime.

Root changes in buccal versus palatal maxillary impacted canines of adults: A longitudinal and retrospective 3-dimensional study before and after orthodontic traction.

OBJECTIVE: Maxillary impacted canines (MIC) could suffer root changes after canine traction. The aim of this study was to evaluate the 3-dimensional root changes in buccal versus palatal MIC after orthodontic traction. MATERIALS AND METHODS: This longitudinal and retrospective study included pre-treatment and after traction cone beam computed tomography scans (CBCTs) of 30 subjects with unilateral/bilateral MIC. A total of 43 MIC were divided into 2 groups: buccal (n=17) or palatal (n=26). Root changes in length and area after orthodontic traction were measured at sagittal, coronal and axial sections. Intergroup comparison was carried out by t or U Mann-Whitney tests, depending on normality. Multiple linear regression analysis was used to evaluate the influence of all predictor variables on root changes (P<0.05). RESULTS: Significant difference between groups was found for root area changes in the upper limit of the cervical third at axial section that showed greater appositional values for the palatal impacted canine group (-1.18mm2) and resorptive values for the buccal impacted canine group (0.62mm2) (P=0.024). Position of impaction palatal influenced the increase of root area in the coronal section and in the upper limit of the cervical third at axial section. Age directly influenced the decrease of total length and root area in sagittal and coronal sections, respectively. CONCLUSION: Orthodontic traction of MIC produced an important appositional root change in the palatal impaction group in the axial root area of the upper limit of the cervical third. Impaction position and age influenced the increase and decrease of root area and length of some specific radicular regions.