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Introduction Non-syndromic oral clefts, affecting one in 700 newborns in India, are the most prevalent craniofacial anomalies, with genetic or environmental causes impacting various life aspects. Studies indicate higher dental disturbances, particularly impacted canines, in cleft lip and palate (CLP) patients compared to non-cleft individuals. Impacted canines, trapped by hard tissues, require early diagnosis to prevent orthodontic issues. The widely used Ericson and Kurol method employs orthopantomograms (OPGs) to classify canine impaction in typical children. However, diagnosing canines in CLP patients is challenging due to palate defects and post-grafting complications. This study aims to compare the utility of the Kumar and Daigavane (KD) grading system and the sector classification to determine the best method for diagnosing impacted canine eruption paths. Method This cross-sectional comparative observational study was conducted at Sharad Pawar Dental College's Department of Orthodontics and Dentofacial Orthopaedics. The sample size, calculated using a significance level of 5% and a prevalence of 1%, required a minimum of 16 participants aged 9-11 years with non-syndromic clefts and impacted canines. Patients with systemic diseases or over 12 years of age were excluded. The sectoral and KD classification systems collected and evaluated OPGs from qualifying cleft patients. Sector classification considered the angle between the occlusal plane or canine tip and the adjacent tooth's long axis, while KD's classification considered the Frankfort horizontal plane, occlusal plane, vertical height from the occlusal plane, canine apex root position, and canine exposure to the cleft defect. Results The study found an 81.25% agreement between the KD grading system and the sector classification, with a Cohen's kappa value of 0.586, indicating a moderate agreement. The KD system showed 81.82% sensitivity and 80.00% specificity, with positive and negative predictive values of 90.00% and 66.67%, respectively. The receiver operating characteristic (ROC) curve analysis revealed the KD system's superior performance in identifying impacted and non-impacted canines compared to the sector classification. Conclusion The KD grading system demonstrated higher efficacy than the sector classification for evaluating the impacted canines in children with unilateral cleft lip and palate (UCLP). The KD system's high sensitivity and specificity make it a valuable tool for predicting canine eruption paths and addressing anatomical challenges in cleft conditions. This study highlights the need for accurate diagnostic tools tailored to cleft patients and contributes to advancing orthodontic treatment outcomes through improved classification systems.

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Objectives: The goal of the study was to analyze the eruption time of the maxillary impacted canines treated with the "canine first technique" and evaluate the success rate. Materials and methods: A total of 103 patients with 131 impacted canines were treated. Alpha angle, Erickson-Kurol sectors, and age were studied to assess the difficulty of canine eruption. All the canines were treated with the "canine first" approach. The median follow-up time was evaluated using the Kaplan-Meier inverse procedure. The primary outcome (canine eruption time) was analyzed using Kaplan-Meier curves. The curve comparison between the different known risk factors was made using the log-rank test. The median eruption time (95% confidence interval) was calculated for each result. Results: The majority of the canines (66.4%) were placed palatally and positioned in sector 3 (30.16%). The median alpha angle was 38.7°. In 88.9% of cases, canines erupted and the median time of eruption was 4.2 months. A statistically significant difference in alpha angle >/<22° able to influence the eruption time was assessed. The variation of the alpha angle (>/<22°) has found to be statistically significative when compared to the eruption time variation. Conclusion: The canine first technique is effective for the eruption of impacted canines, and an alpha angle <22° can be considered a favorable prognostic factor.

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Objectives: The current study aims to explore the stress distribution along the roots of palatally positioned maxillary canines during orthodontic movement using a novel computational spring model. Methods: An experimental analysis based on the spring-model was utilized to calculate Orthodontic Tooth Movement (OTM) and the resulting stresses. Two sets of experiments were conducted: the first set compared stresses on a canine resulting from a single force and a force-couple, while the second set simulated canines' traction during instantaneous movement with varying original tooth angulations using different off-the-shelf orthodontic coils. In total, 130 simulations were performed. Results: The model provided estimated stress distribution throughout the OTM with the expected movements, producing consistent outcomes with prior findings. In the first set of experiments, the force couple exhibited an average stress of 43 KPa, while a single force yielded 51 KPa on average. The maximum stress observed was 63 KPa for the force couple and 130 KPa for a single force. Note that the stress distribution attributed to the force couple was alleviated in comparison to the stress distribution caused by a single force. Force couples generated higher average stress. In the second experiment, the application of an occlusally-directed inclined force led to reduced stress levels overall. For instance, when a 200 g distal force was exerted on the canine, it generated an average stress of 20 KPa, whereas applying a force of the same magnitude in an occlusal-distal direction resulted in a lower average stress of 15.5 KPa. Conclusions: Lower average stress levels when using a force couple indicate that larger loads might be safely applied for rotational movements. Given that areas under maximal stress are prone to damage, orthodontic treatment planning should carefully consider stress distribution to minimize potential harm in these high-stress zones. The results also suggest that force couples enable the use of stronger forces than a single force. Additionally, it is advisable to extrude the tooth initially before starting any horizontal movement towards the target position. Clinical significance: Given that orthodontic treatment often relies on virtual planning, incorporating a variety of methods to evaluate stress distribution within the treatment strategy could offer numerous benefits. Such an approach holds the potential to improve both the efficiency and safety of orthodontic treatments, especially in complex cases that require the application of high forces.

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Background: The canine plays a vital role in dentofacial aesthetics and function. It supports the base of the alar and upper lip, which are crucial for smile aesthetics. When impacted, these functions are lost, leading to low self-esteem and overall poor health-related quality of life. The present study was conducted to find the prevalence of impacted and transmigrated canines in orthodontic patients and also to find the most prevalent type of canine impaction. Materials and Methods: This retrospective study was conducted in a hospital setting at Dental College. A total of 3050 OPGs (Orthopantomagram) of patients who visited dental hospitals for orthodontic treatment constituted the final sample. Demographic details regarding age, gender, and place of residence were collected from the patients. Evaluation of sample radiographs on the standard light box was performed to collect data regarding impacted and transmigrated canines. Statistical analysis was performed using descriptive statistics and Chi-square test. Results: Prevalence of impacted canine was found to be 2.46%. Impacted canine prevalence of 1.53% and 2.85% was reported in males and females, respectively. Only two female patients had transmigrated mandibular impacted canines. Comparison of arch showed a statistically significant (P value 0.02) higher prevalence in the maxillary arch, which was 1.54%, and in the mandibular arch, it was 0.92%. The present study reported significantly more unilateral impactions (P value 0.00) than bilateral impactions. Conclusion: The overall prevalence for impacted canine was 2.46%. Prevalence was higher in female patients. Early diagnosis of impacted canines is vital for planning orthodontic treatment in such patients.

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OBJECTIVE: To evaluate canalis sinuosus (CS) and accessory canalis sinuosus (AC) morphology and their relationship with the impacted canine on cone-beam computed tomography (CBCT) images. METHODS: The diameter and location of the CS, its distance from the nasal cavity (NC-CS), its distance from the buccal cortical plate (BC-CS), and its distance from the alveolar ridge crest (AR-CS) were evaluated on 1000 CBCT scans. The prevalence and termination of AC and the presence of impacted canines were also evaluated. RESULTS: CS was detected in 89 (8.9%) of 1000 CBCTs. The mean CS diameter was found as 1.34 ± 0.53 mm. No statistically significant difference was found between gender, age, direction, and CS presence and diameter. CS was most frequently seen in regions 11 (23.6%) and 13 (23.6%). The average NC-CS, BC-CS, and AR-CS length was 6.14, 6.06 and 4.35 mm, respectively. AC was detected in 22 patients (24.71%). There was no statistically significant difference between the presence of AC and gender, age, CS diameter, NC-CS, BC-CS, and AR-CS distance. BC-CS length and AR-CS length were statistically significantly higher in patients with impacted canines. CONCLUSIONS: It should be kept in mind that the CS diameter, NC-CS, BC-CS, and AR-CS distance may increase in the presence of an impacted canine and the integrity of the neurovascular structure should be preserved. The fact that the CS is often localized in the palatial region requires a detailed evaluation of the anterior maxillary region with three-dimensional imaging methods.

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OBJECTIVE: This randomized clinical trial aimed to assess the feasibility of computer-assisted open exposure of palatally impacted canines. MATERIALS AND METHODS: Patients aged 11-30 years who required orthodontic eruption for the full palatal impaction of their canines were included in this study. Exclusion criteria were psychosocial and dental contraindications of orthodontic treatment, congenital craniofacial disorders, and trauma in the patient's history in the vicinity of the surgical site. Virtual planning software was used to register the intraoral scans and cone-beam computed tomography data and to design a surgical template. In the test group, exposure of the canines was guided by a surgical template, whereas in the control group, the surgeon relied on the surgical plan to localize the impacted canine. The success of the intervention, duration of surgery, and complications, including excessive hemorrhage, damage to the canine or neighboring anatomical landmarks, and postoperative inflammation of the surgical site were assessed. Postoperative pain was reported by the patients using the visual analog pain scale (VAS). RESULTS: Surgery was deemed successful in all patients in both groups. During healing, no complications were observed. The duration of surgery decreased significantly in the test group (4 min 45.1 s ± 1 min 8.4 s) compared to that in the control group (7 min 22.3 s ± 56.02 s). No statistically significant differences were observed between the VAS scores of the two study groups. CONCLUSIONS: The application of virtual planning and static navigation is a viable approach for the open exposure of palatally impacted canines. CLINICAL TRIAL REGISTRATION NUMBER: NCT05909254. CLINICAL SIGNIFICANCE: Computer-assisted surgery is a feasible method for open exposure of palatally impacted canines, which decreases the duration of surgery compared to the freehand method.

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INTRODUCTION: This study aimed to use cone beam computed tomography (CBCT) to evaluate the dimensional and morphological characteristics of unilaterally impacted canines, their effects on adjacent teeth, and differences with contralaterally erupted canines. MATERIALS AND METHODS: A sample of 31 patients (22 males, mean age 22.22 ± 4.82 years; 9 females, mean age 23.91 ± 5.16 years) with unilaterally impacted maxillary palatal teeth were included in the study. CBCT images were obtained using a NewTom 5 G unit in standard mode. Three-dimensional multiplanar reconstructions emulating a panoramic view and curved planar reconstructions were evaluated. Individuals were divided into two groups (low- and high-complexity) according to Ericson and Kurol's impaction complexity classification. RESULTS: The crown lengths and mesiodistal crown widths of the impacted canines were similar to the symmetric canine on the opposite arch and significantly larger than adjacent lateral and premolar teeth (p<0.05). The alpha (31.33 ± 8.32) and beta angles (39.53 ± 10.31) and the 'h' height (10.11 ± 2.02) values in the low-complexity group were significantly lower than the high-complexity group (alpha angle=57.40 ± 12.15; beta angle=71.31 ± 13.94; 'h' height=14.35 ± 3.71, and alpha angle: p<0.001; beta angle: p<0.001; 'h' height: p=0.002) CONCLUSION: The root lengths of impacted maxillary canine teeth are significantly shorter than symmetrically erupted canine teeth regarding labiolingual crown width. As the alpha and beta angles and 'h' height increase, the complexity level of the impacted canine also increases.

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Background: To our knowledge, no systematic review assessed and gathered information about the prevalence of impacted canines among the Saudi population. The purpose of this study was to critically assess the previously published studies about the prevalence of canine impaction according to impaction type (buccal/ palatal), gender (male/female), and location (maxillary/mandibular, right/left), are among the Saudi population. Methods: PubMed (MEDLINE), Scopus, the Web of Science, Dimensions, and Semantic Scholar databases were searched systemically for articles related to the topic of the study published between 1987 and 2022. The PRISMA statements were used to conduct a systematic review with the help of the Best Practice for Survey and the Public Opinion Research scales by the American Association for Public Opinion Research (AAPOR) to assess and evaluate the selected studies' quality. Results: The initial search of the databases yielded 221 articles. After discarding duplicates, 161 were selected for further evaluation. Eventually, 16 articles were selected for inclusion in this study. Regarding the quality of the selected articles, all articles, except one, were of high quality. Only one was of medium quality. Conclusion: It was found that the incidence of palatal canine impactions was higher than buccal impactions. Females had a higher prevalence of canine impactions as compared to males. There were more canine impactions in the maxilla than the mandible and more on the left side than the right one.

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OBJECTIVE: We propose a method utilizing mixed reality (MR) goggles (HoloLens 2, Microsoft) to facilitate impacted canine alignment, as planning the traction direction and force delivery could benefit from 3D data visualization using mixed reality (MR). METHODS: Cone-beam CT scans featuring isometric resolution and low noise-to-signal ratio were semi-automatically segmented in Inobitec software. The exported 3D mesh (OBJ file) was then optimized for the HoloLens 2. Using the Unreal Engine environment, we developed an application for the HoloLens 2, implementing HoloLens SDK and UX Tools. Adjustable pointers were added for planning attachment placement, traction direction, and point of force application. The visualization was presented to participants of a course on impacted teeth treatment, followed by a 10-question survey addressing potential advantages (5-point scale: 1 = totally agree, 5 = totally disagree). RESULTS: Out of 38 respondents, 44.7% were orthodontists, 34.2% dentists, 15.8% dental students, and 5.3% dental technicians. Most respondents (44.7%) were between 35 and 44 years old, and only 1 (2.6%) respondent was 55-64 years old. Median answers for six questions were 'totally agree' (25th percentile 1, 75th percentile 2) and for four questions 'agree' (25th percentile 1, 75th percentile 2). No correlation was found between age, profession, and responses. CONCLUSION: Our method generated substantial interest among clinicians. The initial responses affirm the potential benefits, supporting the continued exploration of MR-based techniques for the treatment of impacted teeth. However, the recommendation for widespread use awaits validation through clinical trials.

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OBJECTIVE: To compare the periodontal outcomes of surgically exposed and orthodontically aligned buccally impacted maxillary canines to spontaneously erupted maxillary canines. DATA SOURCES: An unrestricted search was carried out of indexed databases (Medline, EMBASE, Web of Science and Scopus), reference lists of included studies, and grey literature published until December 2023. DATA SELECTION: Observational and experimental studies that addressed the focused question 'Do periodontal outcomes of buccally impacted maxillary canines that were surgically exposed and subsequently extruded and aligned using orthodontic alignment, differ from those of spontaneously erupted maxillary canines?' were included. DATA EXTRACTION: Study screening, selection and data extraction were performed independently by two authors, with disagreement resolved by a third reviewer. The risk of bias was assessed using the JBI Critical Appraisal Checklist and GRADE approach. RESULTS: A total of 857 citations were found and five studies were eligible for inclusion. Supragingival plaque accumulation and gingival inflammation were similar between impacted canines and their contralaterals in most studies. Meta-analyses revealed no significant differences in keratinised tissue width (prospective studies: MD = -0.28, 95% confidence interval [CI] = -1.13-0.56, I² = 78%; retrospective studies: MD = 0.61, 95% CI = -1.51-2.72, I² = 94%). However, a meta-analysis of prospective studies showed slightly greater mean probing depth for impacted canines compared to their contralateral canines (prospective studies: MD = 0.16, 95% CI = 0.04-0.28, I² = 0%). The evidence certainty for keratinised tissue width and probing depth outcomes was low. CONCLUSION: Surgically exposed and orthodontically aligned buccally impacted canines have slightly greater probing depths, potential bone loss and increased clinical crown length, compared to their counterparts. However, these small differences (<1 mm) are unlikely to be clinically significant.

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BACKGROUND: This study aimed to investigate the potential associations between alveolar bone thickness, bucco-palatal inclination of maxillary lateral incisors, and lateral incisor root resorption in patients with unilateral maxillary impacted canines (UMICs). METHODS: A total of three hundred and five subjects (120 males, 185 females; mean age, 16.39 years; standard deviation, 4.04) with UMICs were included. Canine position and root resorption were assessed using CBCT. UMICs were divided into palatal, buccal and mid-alveolus groups (PICs, BICs and MAICs), with 117, 137 and 51 subjects, respectively. Alveolar bone thickness and bucco-palatal inclination of lateral incisors were measured using the Dolphin software. RESULTS: The prevalence of lateral incisor root resorption was significantly lower in the BICs (13.9%) than MAICs (29.4%) and PICs (29.1%). Alveolar bone thickness of the apical area was smaller in UMICs with lateral incisor root resorption than no resorption in both PICs (8.33 ± 1.64 vs 10.53 ± 2.55 mm) and BICs (8.94 ± 1.85 vs 10.76 ± 2.28 mm). Furthermore, lateral incisors on the impacted side were more buccally inclined in PICs with lateral incisor root resorption than no resorption, while in both BICs and MAICs, there was no statistical difference between lateral incisor root resorption than no resorption. Moreover, alveolar bone thickness of the apical area, rather than bucco-palatal inclination of lateral incisors, was significantly correlated with lateral incisor root resorption both in PICs and BICs. CONCLUSIONS: Lateral incisor root resorption is less common in BICs. Thinner alveolar bone thickness at the apical area of lateral incisors can be considered as a potential risk factor for lateral incisor root resorption in UMICs.

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Objectives. This study aimed to analyze the inter-molar width and skeletal base class to predict maxillary canine impaction in permanent dentition. Methods. This cross-sectional study was carried out between September 2021 to March 2022. Patients aged between 13 and 20 years were recruited. These patients' cone-beam computer tomography(CBCT), lateral cephalogram, and dental casts were collected and analyzed. For statistical analysis, T-test and Chi-square tests were applied. Results. A total of 92 patients were enrolled in this study. Inter-molar width was significantly decreased in patients with impacted canine(P < .001). The skeletal base classification was statistically significant when compare with intermolar width(P < .05). The location of impaction (P = .060), type of impaction(P = .435), and side of impaction(P = .239) were determined to be statistically insignificant. Conclusion. The Inter-molar width was decreased in patients with impacted canine; therefore, it may be a potential risk factor. The skeletal classification was found to affect inter-molar width in impacted canine patients.

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INTRODUCTION: The aim of this study was to investigate the maxillary width within individuals with a unilaterally impacted maxillary canine and to determine any association between the impacted canine location and some canine-related variables. METHODS: A cross-sectional analytical study using a split-mouth design included 22 CBCTs of individuals with unilaterally impacted maxillary canines (a total of 44 sides). The maxillary width was measured and compared in both impacted and non-impacted sides at various levels: basal, alveolar, and dental. The following canine-related variables were analyzed and compared with impaction location: impacted canine angulation, cusp tip distance from the occlusal plane, type of impaction (vertical or horizontal), presence of root resorption, deciduous teeth, or adjacent teeth transposition. Significance was considered at P < 0.05. RESULTS: There was a significant reduction in maxillary width on the impacted side at the following levels: maxillary first premolar alveolar crest in both coronal and axial sections, dental width measured from the central fossa of maxillary first molar to the midline, and width measured from the canine cusp tip to the midline. Moreover, the distance from the palatally impacted canine cusp tip to the occlusal plane was statistically significantly lower (7.6 ± 1.5 mm) compared to buccal (10.8 ± 3.3 mm) and mid-alveolus (12.0 ± 3.9 mm) impaction, (P values = 0.02). CONCLUSIONS: There was a significant association between canine impaction and reduction in the maxillary width at least on the dental level. The palatally impacted canine cusp tip was significantly closer to the occlusal plane compared to the buccal and mid-alveolar impaction.

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The purpose of this research was to test the reliability of a modified magnification method for determining the position of an impacted canine from a single panoramic radiograph. This retrospective study evaluated 114 panoramic radiographs showing 136 impacted maxillary canines. The widths of the impacted canines, contralateral erupted canines, and ipsilateral maxillary incisors were measured, and ratios for the canine-incisor index (CII) and canine-canine index (CCI) were calculated. The impacted canines were also classified according to their location in the vertical plane (apical, middle, or coronal zone) relative to the contralateral central incisor. Continuous data were analyzed for normal distribution, and logistic and multivariate logistic regression models were conducted. The Benjamini-Hochberg procedure with a false discovery rate of 0.05 was used to account for multiple testing. The intrarater reliability was excellent for impacted canine, central incisor, and contralateral canine measurements (intraclass correlation coefficient > 0.9). The CII and vertical zone were strong predictors of an impacted canine position with clinically useful sensitivity and specificity values (0.69 and 0.74, respectively, based on an area under the curve concordance statistic of 0.75). A predictive range was evident for the CII of palatally (1.10-1.39) and buccally (0.90-1.19) impacted canines in the middle and coronal zones, respectively. The occurrence of palatal or buccal positioning was not significantly associated with the CCI (P = 0.2). The CII and vertical zone identified from a single panoramic radiograph can be used to determine the buccopalatal position of an impacted canine, with more reliability if the impacted canine crown is in the middle or coronal zone of the contralateral central incisor.

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OBJECTIVES: Automating the digital workflow for diagnosing impacted canines using panoramic radiographs (PRs) is challenging. This study explored feature extraction, automated cropping, and classification of impacted and nonimpacted canines as a first step. METHODS: A convolutional neural network with SqueezeNet architecture was first trained to classify two groups of PRs (91with and 91without impacted canines) on the MATLAB programming platform. Based on results, the need to crop the PRs was realized. Next, artificial intelligence (AI) detectors were trained to identify specific landmarks (maxillary central incisors, lateral incisors, canines, bicuspids, nasal area, and the mandibular ramus) on the PRs. Landmarks were then explored to guide cropping of the PRs. Finally, improvements in classification of automatically cropped PRs were studied. RESULTS: Without cropping, the area under the curve (AUC) of the receiver operating characteristic (ROC) curve for classifying impacted and nonimpacted canine was 84%. Landmark training showed that detectors could correctly identify upper central incisors and the ramus in ∼98% of PRs. The combined use of the mandibular ramus and maxillary central incisors as guides for cropping yielded the best results (∼10% incorrect cropping). When automatically cropped PRs were used, the AUC-ROC improved to 96%. CONCLUSIONS: AI algorithms can be automated to preprocess PRs and improve the identification of impacted canines.

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BACKGROUND: Orthodontic treatment planning for an impacted canine tooth requires accurate information about its position. The aim of this study was to compare the diagnostic accuracy of two conventional orthodontic radiographic modalities with cone-beam computed tomography (CBCT) for localization of impacted maxillary canine teeth. MATERIALS AND METHODS: Panoramic radiographs, lateral cephalograms, and CBCT scans of 30 patients with unilaterally impacted maxillary canine teeth were retrieved from the archives. Eight expert orthodontists evaluated the parameters related to the location of impacted canine teeth by using panoramic radiographs and lateral cephalograms of patients. After 4 weeks, the same parameters were evaluated on CBCT scans of patients. The diagnostic accuracy of conventional modalities and CBCT was compared with each other and also with the gold standard. RESULTS: The conventional radiographic modalities and CBCT had similar accuracy for assessment of the overall inclination (p = 0.11), apex morphology (p = 0.18), and mesiodistal position of the apex (p = 0.12). CBCT had significantly higher accuracy for determination of incisal tip location (p = 0.001), labiopalatal (p = 0.001) and vertical (p = 0.01) position of the crown tip, minimum bone thickness covering the crown (p = 0.001), and root resorption of the adjacent tooth (p = 0.001). CONCLUSION: The combination of panoramic radiographs and lateral cephalograms was sufficiently accurate to assess some diagnostic parameters such as overall inclination, apex morphology, and mesiodistal apex location of impacted canine teeth.

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The eruptive deviation of the permanent maxillary canine must be identified early, at the beginning of the second transitional period of the mixed dentition. Acting at this moment is fundamental for its spontaneous redirection and eruption. The aim of the paper is to present a case where the extraction of the deciduous canines was the choice for redirecting the maxillary permanent canines with eruptive palatal deviation, as well as to suggest a sequence of procedures for diagnosis and choice of treatment. The success of deciduous canine extraction in redirecting the ectopic permanent canines is discussed in this case, as well as aspects that might lead to failure. Still, it highlights the importance of computed tomography for choosing conservative treatment or traction, including it in the sequential guideline for acting in these cases.

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Objective: To evaluate the effectiveness of a minimally-invasive corticotomy-assisted treatment of palatally impacted canines (PICs) compared with the traditional method by evaluating treatment time, the velocity of movement, and the associated dentoalveolar changes. Materials and methods: Forty-six patients with palatally or mid-alveolar upper impacted canines were recruited and distributed into two groups: the corticotomy-assisted traction group (CAT group, mean age: 20.39±2.27 years) and the traditional treatment group (TT group, mean age: 20.26±2.17 years). The closed surgical approach was used in both study groups. The velocity of traction movement, traction duration and overall treatment duration were evaluated clinically. In addition, the bone support ratios and the amount of root resorption were assessed on cone-beam computed tomography (CBCT) images. Results: At the end of treatment, significant differences were found between the two groups regarding the velocity of traction movement, traction time, and overall treatment time (P<0.05). The mean velocity of traction movement in the CAT group was greater than the TT group ( x velocity=1.15±0.35 mm/month; 0.70±0.33 mm/month, P=0.027, respectively). The duration of the active traction and the overall orthodontic treatment in the CAT group were significantly shorter than the TT group by 36% and 29%, respectively. The mean bone support ratios of the aligned canines did not differ significantly between the two groups (88% vs. 89% in the CAT and TT groups, respectively). No significant differences were found between the two groups regarding the mean amount of root resorption on the adjacent laterals ( x resorption = 1.30±1.18 mm; 1.22±1.02 mm, P=0.612, in CAT and TT groups, respectively). Conclusions: The traction movement velocity of the palatally impacted canines can be increased using minimally-invasive corticotomy-assisted orthodontic treatment. The side effects of the acceleration procedure were minimal and almost similar to those of the traditional technique.

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Background: The risk of palatally displaced canines (PDCs) rises in patients with tooth agenesis. The orthodontic extrusion and alignment of PDCs require adequate anchorage to enable tooth movement and control the side effects. There is no paper presenting treatment in the case of severe oligodontia with simultaneous PDCs and the use of mini-implants (MIs) for their orthodontic extrusion. Case presentation: A 15-year-old patient presented with non-syndromic oligodontia and bilateral PDCs. Cone beam computed tomography revealed that both PDCs were in proximity to the upper incisors' roots. There was no evident external root resorption of the incisors. The "canines first" approach was chosen. MIs were used both as direct and indirect anchorage. First, the extrusive forces of cantilevers were directed both occlusally and distally. Next, the buccal directions of forces were implemented. Finally, fixed appliances were used. PDCs were extruded, aligned, and torqued. Proper alignment and occlusion were achieved to enable further prosthodontic restorations. Conclusions: The use of MIs made it possible to avoid collateral effects, reduce the risk of complications, and treat the patient effectively. MIs provide adequate anchorage in demanding cases. The use of MIs for the extrusion of PDCs made it possible to offer this treatment option to patients with severe oligodontia. The presented protocol was effective and served to circumvent treatment limitations associated with an inadequate amount of dental anchorage and a high risk of root resorption.

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BACKGROUND: The prognosis of orthodontic treatment for a patient with impacted canine teeth can be affected by many factors and understanding some of the characteristics of impacted teeth can increase the effectiveness and reduce the duration of treatment. This study aims to explore the effects of positions and dentoalveolar morphological characteristics of impacted maxillary canines on the prognosis of orthodontic treatment. METHODS: In this study, forty-six adolescent individuals who applied for treatment of impacted teeth were divided into three groups: CC (no impacted maxillary canine group), BC (unilateral buccally positioned impacted maxillary canine group), and PC (unilateral palatally positioned impacted maxillary canine group). The impacted canine and adjacent teeth were evaluated in terms of position, angulation, inclination, mesiodistal and buccolingual widths, root length, dilaceration angle, and root resorption. RESULTS: The mean values of U3 Ang (angulation of the maxillary impacted canine) and U3/U2 angles (maxillary impacted canine and lateral incisor angle) were statistically significantly higher in the BC and PC groups (p < 0.001). The mean values of U2 RL (lateral incisor root length) and U3 RD (canine root dilaceration angle) were statistically significantly lower in the BC and PC groups. CONCLUSIONS: The results of this study suggest that shorter root lengths and increased angulation values may lead to the ectopic eruption of canines. The higher canine angulations in the PC group increase the degree of root resorption.