Etiology of maxillary canine impaction: a review

The sacrosanct canine: Considerations for the extraction of severely displaced, or impacted maxillary canine(s)

OBJECTIVE

The maxillary canines have long been considered critical for dental function and aesthetics, with traditional practice prioritizing their preservation and alignment. However, this view often stems from outdated teachings rather than evidence-based principles, since there is no scientific support for the concept of canine-protected occlusion. Therefore, this commentary paper provides justification for extraction of severely impacted maxillary canines with first premolar substitution.

RESULTS

In cases of severely impacted maxillary canines, orthodontic alignment may be associated with higher morbidity, unpredictable outcomes, prolonged treatment times, and increased patient burden. As an alternative, extracting the impacted canines and substituting the first premolars offers a viable, efficient solution that can achieve functional and aesthetic outcomes with fewer complications.

CONCLUSION

This paper challenges traditional perspectives on the management of impacted canines, advocating for an evidence-based approach that prioritizes patient-centered care.

Possible link between the preferential unilateral chewing side and eruptive guidance of the maxillary canine germ : Cross-sectional study on panoramic radiographs

AIM

To determine whether unilateral preferent chewing (UPC) affects the position and angulation of the permanent maxillary canine germ on the preferred side.

MATERIALS AND METHODS

In a retrospective cross-sectional study, medical records from children 7.91(± 0.8) years old with unilateral preferred chewing side and unilateral posterior crossbite were selected. The position of the maxillary canines was analysed by measuring the following angles and distances: the angles formed between the canine axis and the midline (PS; potential impact range > 15°), and that between the canine axis and the bicondylar line (W; potential impact range < 75°). In addition, the canine's position with respect to the lateral incisor (EK; potential impact range > II) and the distance between the canine cusp and the occlusal plane (CCOP potential impact range > 10 mm) were measured.

RESULTS

The final sample consisted of 106 radiographs; thus, a total of 212 maxillary canines were analysed. Tooth angulation on the preferred chewing side was higher for the angle PS with an average angle of 13.88° (± 7.56) and its position was more frequently found in sector II (49.1%), according to the EK analysis, compared to its contralateral that had an average of 11.75° (± 10.13) for the PS angle and a frequency of 67% in the sector I (p < 0.05 in both analyses). The data obtained for the angle W resulted in an average of 76.12° (± 9.09), while on the contralateral side it was 77.16° (± 12.56; p = 0.012). Lastly, according to the CCOP analysis, the preferred chewing side measured on average 15.3 mm (± 2.4), while on the nonpreferred side it was 15.19 mm (± 2.43; p = 0.143).

CONCLUSIONS

Based on this research, UPC seems to have a certain unfavourable influence on canine position and angulation. Thus, this is another factor to consider in decision-making regarding early treatment of this development disorder.

Surgical-orthodontic approach of two palatally impacted canines with maxillary lateral incisor anomalies in a growing class II patient: A case report

INTRODUCTION

After the mandibular third molars, the maxillary canines are the most displaced or impacted teeth in permanent dentition. Surgical-orthodontic disimpaction of impacted canines, followed by aesthetic reconstructions, can be a successful treatment choice.

AIM

The aim of this case report was to describe the smile restoration through simultaneous surgical disimpaction of the two upper permanent canines in a 13-year-old patient who also presented with agenesis of the right upper lateral incisor and a conoid-shaped left upper lateral incisor.

TREATMENT PROTOCOL

The present case report followed the Care Checklist For Case Reports. After having completed the multibrackets fixed orthodontic therapy phase necessary for the preparation of the anchorage, avulsions of the upper deciduous canines were carried out, followed by the making of surgical full thickness palatal flap in order to perform traction of the permanent canines, and an orthodontic eyelet with passive metal looped ligatures was applied. One week after the surgery, traction was started with Crescini-double arch technique. Subsequently, the avulsion of elements 2.2 and 5.2 were executed. At the end of orthodontic treatment, in order to optimise the aesthetics and function of the canines, a restorative treatment was carried out.

RESULTS AND CONCLUSIONS

After the surgical creation of a palatal flap, the disimpaction of the two upper canines, using the double arch technique, allowed the teeth to be moved into the desired position on the upper arch.

Palatal canine impaction is associated with craniofacial shape in humans

BACKGROUND/OBJECTIVES

It is unclear whether palatal canine impaction is related to genetic or local/environmental factors. If a genetic origin is assumed, then it could be expected that palatal canine impaction is associated with overall craniofacial development. Within this context, the aim of this study was to evaluate the craniofacial morphology of individuals with palatal canine impaction and compare it to a matched group of normal controls.

MATERIALS/METHODS

The sample for this investigation comprised 404 individuals (232 females and 172 males). Half of these individuals presented with unilateral or bilateral palatal canine impaction confirmed clinically and radiographically. The other half were matched for sex and age with the first half and comprised individuals without tooth impaction, apart from third molars. The shape of the craniofacial structures was outlined on calibrated cephalometric images through 15 curves and 127 landmarks (11 fixed and 116 semi-landmarks). Shape configurations were superimposed using Procrustes Superimposition and the resulting shape coordinates were reduced into principal components for all subsequent analyses. The effect of palatal canine impaction on craniofacial shape was assessed with regression models, separately in females and males. All statistical tests were performed assuming a type-1 error of 5%.

RESULTS

Individuals with palatally impacted canines appear to have a less convex face, a more brachyfacial skeletal pattern, and a sagittally extended premaxilla. In females effect sizes ranged between η2 = 0.136-0.397 (P < 0.05) and in males between η2 = 0.125-0.396 (P < 0.05, apart from the entire craniofacial configuration: P = 0.259).

LIMITATIONS

Palatal canine impaction was not confirmed through cone beam computer tomography images in all patients, however, in those cases, the treatment history confirmed the diagnosis.

CONCLUSIONS/IMPLICATIONS

Palatal canine impaction is related to a distinct craniofacial shape in females and males. These findings allow for speculation that palatal canine impaction is affected by genetic pathways involved in overall craniofacial development.

Two-Dimensional Radiographic Diagnosis of Maxillary Canine Impactions

Background: The primary aim of this study was to evaluate, using conventional radiographic imaging, the height, angulation, and mesiodistal position of impacted maxillary canines to determine if these variables are significantly associated with the palatal or buccal positioning of the tooth. Methods: A retrospective analysis was conducted on all patients diagnosed and treated for at least one impacted maxillary canine over a 4-year period in the Principality of Asturias. The final sample included 159 impacted canines. The variables analyzed were age, gender, associated pathology, location, angulation, height, mesiodistal position, buccopalatal position, and treatment method. Follow-up periods ranged from 12 to 50 months. Results: The mean age of the patients was 21 years (range 10-41 years), with most cases occurring in patients aged 14 to 30 years. Females accounted for 66.1% of the sample, with a female-to-male ratio of 1.95:1. The type of treatment (extraction/traction, surgical-orthodontic approach) was significantly associated with patient age. Additionally, the proximity of the impacted canine crown to the palatal or buccal cortices was significantly related to the treatment choice. However, no significant relationship was observed between the palatal/buccal position of the canine crown and its height or angulation. Conclusions: In the present work, the upper canines included by the palatal did not have a greater height or angulation than the canines included by the vestibule.

Orthodontic traction of a deeply impacted mandibular first molar via a ramus miniscrew through lateral-window technique: A case report

BACKGROUND

The incidence of mandibular first molar impaction is less than 0.01%, and there are no standard treatment guidelines. Orthodontic traction can be chosen as a treatment plan in some circumstances. One miniscrew in the mandibular ramus can offer sufficient anchorage for the traction of impacted mandibular molars.

CASE DESCRIPTION

A 10-year-old boy had a completely labially positioned maxillary left canine and a deeply impacted mandibular left first molar associated with a dentigerous cyst. Using 2 palatal miniscrews for distalization, space was created to align the maxillary left canine. In addition, a miniscrew in the mandibular ramus facilitated the traction of the mandibular left first molar. After 3 years and 6 months of orthodontic treatment, the integrity of the dental arch was restored, and occlusal function was reestablished.

PRACTICAL IMPLICATIONS

A ramus miniscrew is an effective and viable treatment option for the orthodontic traction of deeply impacted mandibular molars.

Aesthetical and Functional Rehabilitation for an Ankylosed Maxillary Canine-A Case Report

Background: As the functional and aesthetical importance of the canine cannot be overstated, the management of a missing canine is challenging. This case report describes the treatment of an infra-occluded ankylosed maxillary canine in a patient with previously failed orthodontic treatment. Case description: A 20-year-old patient sought a second opinion for orthodontic treatment failure. The patient presented with an impacted, ankylosed, and severely infra-occluded right maxillary canine, as well as an iatrogenic clockwise cant of the maxillary occlusal plane and several root resorptions. The treatment corrected the cant of the occlusal plane while avoiding further root resorption, partially extracted the upper right canine, improved the quality and quantity of the soft tissue in the newly edentulous area, and provided a prosthetic rehabilitation using a lithium disilicate ceramic resin-bonded cantilever bridge. Conclusions: The use of a cantilevered bridge resulted in an aesthetically pleasing and minimally invasive rehabilitation. This technique is reversible, does not affect pulp vitality, and is a viable solution for rehabilitating the smiles of young patients. Clinical significance: The smile rehabilitation for an ankylosed maxillary canine, especially in the case of a previously failed orthodontic treatment, is an important clinical challenge. A minimally invasive long-term restoration with a cantilever bridge is a viable solution. Functional and aesthetically pleasant results can be achieved with a multidisciplinary approach.

Assessment of the positional and morphological differences of unilaterally impacted canines: A cross-sectional study

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.

A hierarchical deep learning approach for diagnosing impacted canine-induced root resorption via cone-beam computed tomography

OBJECTIVES

Canine-induced root resorption (CIRR) is caused by impacted canines and CBCT images have shown to be more accurate in diagnosing CIRR than panoramic and periapical radiographs with the reported AUCs being 0.95, 0.49, and 0.57, respectively. The aim of this study was to use deep learning to automatically evaluate the diagnosis of CIRR in maxillary incisors using CBCT images.

METHODS

A total of 50 cone beam computed tomography (CBCT) images and 176 incisors were selected for the present study. The maxillary incisors were manually segmented and labeled from the CBCT images by two independent radiologists as either healthy or affected by root resorption induced by the impacted canines. We used five different strategies for training the model: (A) classification using 3D ResNet50 (Baseline), (B) classification of the segmented masks using the outcome of a 3D U-Net pretrained on the 3D MNIST, (C) training a 3D U-Net for the segmentation task and use its outputs for classification, (D) pretraining a 3D U-Net for the segmentation and transfer of the model, and (E) pretraining a 3D U-Net for the segmentation and fine-tuning the model with only the model encoder. The segmentation models were evaluated using the mean intersection over union (mIoU) and Dice coefficient (DSC). The classification models were evaluated in terms of classification accuracy, precision, recall, and F1 score.

RESULTS

The segmentation model achieved a mean intersection over union (mIoU) of 0.641 and a DSC of 0.901, indicating good performance in segmenting the tooth structures from the CBCT images. For the main classification task of detecting CIRR, Model C (classification of the segmented masks using 3D ResNet) and Model E (pretraining on segmentation followed by fine-tuning for classification) performed the best, both achieving 82% classification accuracy and 0.62 F1-scores on the test set. These results demonstrate the effectiveness of the proposed hierarchical, data-efficient deep learning approaches in improving the accuracy of automated CIRR diagnosis from limited CBCT data compared to the 3D ResNet baseline model.

CONCLUSION

The proposed approaches are effective at improving the accuracy of classification tasks and are helpful when the diagnosis is based on the volume and boundaries of an object. While the study demonstrated promising results, future studies with larger sample size are required to validate the effectiveness of the proposed method in enhancing the medical image classification tasks.

The "canine first technique" in maxillary impacted canines: analysis of the treatment duration and success of therapy

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.

A Comparative Analysis of Sector Classification and the Impacted Canine Grading System by Kumar and Daigavane in Patients With Unilateral Cleft Lip and Palate Utilizing Orthopantomogram (OPG) as a Diagnostic Tool

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.

Radiographic assessment and management of two deeply and horizontally impacted maxillary central incisors: A clinical case report

This case report describes the treatment of a 9-year-old boy with impacted maxillary central incisors due to 2 supernumerary teeth. A sequential approach comprising of surgical removal of the supernumerary teeth and 2 stages of surgical exposure and orthodontic traction of the impacted teeth resulted in correct repositioning of incisors. Close monitoring and multidisciplinary cooperation during various stages of treatment led to a successful esthetic outcome, with optimal periodontal health and functional occlusion.

Craniofacial morphology in patients with impacted canine: a case control-study

BACKGROUND

The objective of this study was to evaluate the risk of maxillary canine impaction through cephalometric evaluation.

METHODS

One hundred and eighty-two Caucasian patients (80 males and 102 females) with a mean age of 12.4±0.5 were retrospectively enrolled in the present study. Ninety patients with impacted canines were compared with ninety-two patients with physiologically erupted canines. The following cephalometric variables were analyzed: SNA, ANB, SN-GOME, GO-ME, SP-CL, SELLA TURCICA DEPHT, A-Pt LINE, B-Pt LINE, A-Pt LINE°, B-Pt LINE°, A1s-Pt, A1i-Pt, A1s-Pt°, A1i-PT°, A-SN, B-SN and SN-U1. When applicable, a paired sample t-test was performed to investigate the difference in means between the two sample groups, while the Mann-Whitney Test was used as a non-parametric test in the case of a non-normal distribution of data. Statistical significance was set at P<0.05.

RESULTS

The group with impacted canines showed an increase in Go-Me distance, SNA angle and A1s-Pt angle compared with the control group. In addition, the same group showed a decrease in A-SN and SP-Cl distance compared with the control group.

CONCLUSIONS

An increase in mandibular length (GO-ME) and SNA angle associated with a reduction in A-Sn distance and interclinoid distance (SP-Cl) were observed in patients with impacted canines.

Aesthetic assessment of maxillary lateral and canine implant-supported crowns by laypersons and orthodontists

INTRODUCTION

The objectives of this study were to evaluate how laypersons and orthodontists evaluate and rank aesthetic parameters of an implant-supported crown (ISC) on the canine position (ISC-C) and lateral position (ISC-L).

METHODS

A digital survey of 11 cases, 5 ISC-C, 5 ISC-L and 1 control case without ISC, was distributed to 207 laypersons and 296 orthodontists. All cases included one extraoral photograph and three intraoral photographs. The respondents were asked to identify the ISC and to evaluate the aesthetic parameters regarding colour of the implant (CI), shape of the implant (SI) and gingival colour around ISC (GCI). Differences within and between the groups were tested using Chi-2-test and Independent-Samples t-test.

RESULTS

All invited laypersons and 184 orthodontists (62% response rate) answered the survey. Orthodontists (89%) more correctly identified the ISC, regardless of its position, than laypersons (50%) (p < 0.001). Both laypersons (54%) and orthodontists (23%) rated higher proportions of acceptance of CI, SI and GCI in favour for the ISC-L than ISC-C (laypersons: 40%, orthodontists: 10%) (p < 0.001). Assessing each parameter separately, orthodontists rated higher for ISC-L, compared to the ISC-C (p < 0.001). In general, laypersons and orthodontist ranked tooth colour (mean, standard deviation [SD]:8.0,1.5 and 9.0, 1.0) and tooth shape (mean, SD: 8.0, 1.7 and 8.8, 1.2) as aesthetically higher than the gingival colour (mean, SD: 7.2, 2.2 and 8.0, 1.7) (p > 0.001).  Conclusion: Laypersons and orthodontists consider the ISC-L as aesthetically more preferable, compared to the ISC-C.

Radiological features and treatment of erupting maxillary canines in relation to the occurrence of dental developmental abnormalities

OBJECTIVE

This study aimed to investigate the radiological features of the permanent canines and the treatment carried out to ensure their eruption relative to certain features involved in Dental Anomaly Patterns (DAP).

MATERIAL AND METHODS

The cross-sectional part of this retrospective register--based study focused on 1,315 dental panoramic tomographs (DPTs) of children aged 8.5-10.5 years, while the longitudinal part involved information on the treatment provided for 1,269 canines after the DPTs and on their eruption into the oral cavity.

RESULTS

The canines of the DAP children more often showed evidence of early treatment (p = 0.014), with girls having more frequently interceptive treatment (p = 0.004) and boys early headgear (p = 0.022). Delayed dental age was associated with early treatment (OR 3.29, 95% CI 1.08-9.99). Either no or clear overlapping of a canine with the lateral incisor occurred more often in the DAP children, whereas canine inclination did not differ between the groups. The root development stage of the canine was more often either beginning or well advanced in the DAP children.

CONCLUSIONS

The children with dental developmental abnormalities more often showed evidence of early treatment for the canines. Monitoring of the erupting canines after the first mixed stage is important to enable timely early treatment.

"Examining the link between tooth agenesis and papillary thyroid cancer: is there a risk factor?" Observational study

BACKGROUND

Mutations in one or multiple genes can lead to hypodontia and its characteristic features. Numerous studies have shown a strong genetic influence on the occurrence of hypodontia, and identified several genes, including AXIN2, EDA, FGF3, FGFR2, FGFR10, WNT10A, MSX1, and PAX9, that are directly associated with dental agenesis and carcinogenesis. The objective of this study was to investigate the occurrence and pattern of tooth agenesis, microdontia, and palatally displaced canine (PDC) in women diagnosed with papillary thyroid cancer (PTC), compared to a control group of women without any malignancy or thyroid disease.

MATERIALS AND METHODS

This case-control study was carried at the Department of Orthodontics, School of Dental Medicine University of Zagreb, and Department of Oncology and Nuclear Medicine Sestre Milosrdnice University Hospital Centre. The study involved a clinical examination and evaluation of dental status, panoramic X-ray analysis, and assessment of medical and family history of 116 female patients aged 20-40 with PTC, as well as 424 females in the control group who were of similar age.

RESULTS

The prevalence of hypodontia, microdontia, and PDC was statistically higher in women with PTC than in the control group. The prevalence rate of hypodontia was 11.3% in the experimental group and 3.5% in the control group. The experimental group showed a higher occurrence of missing upper lateral incisors, lower left central incisors, and all the third molars (except the upper left) compared to the control group. Women with PTC showed the prevalence of PDC significantly higher than the control group (3.5%, 0.7%, p = 0.002). The probability of hypodontia as a clinical finding increases 2.6 times, and microdontia occurs 7.7 times more frequently in women with PTC.

CONCLUSION

Our study suggests a possible link between odontogenesis and PTC. The absence of permanent teeth may increase the likelihood of PTC in women. Leveraging the age-7 orthopantomogram to identify women at high risk for PTC within a critical early detection window could significantly improve oral health outcomes and PTC prognosis through proactive interventions.

Evaluation of stress and displacement of maxillary canine during the single canine retraction in the maxillary first premolar extraction cases- A finite element study

OBJECTIVES

This finite element study aimed to simulate maxillary canine movement during anterior teeth retraction.

MATERIALS AND METHODS

Three methods of maxillary canine movement including miniscrew sliding with high hooks (MSH), miniscrew sliding with low hooks (MSL), and the traditional sliding method (TS) without using miniscrews were simulated using three-dimensional finite element analysis. The initial displacement of the maxillary canine, the maximum principal stress of the periodontal ligament and the Von Mises stress were calculated.

RESULTS

The distolingual tipping movements of the canine were shown in three movement modes. MSH showed a small tendency to lingual tipping movement and a extrusion movement while MSL had the largest lingual inclination. TS demonstrated a tendency toward distolingual torsion displacement. Compressive stress values were mainly concentrated in the range - 0.003 to -0.006 MPa. For tensile stress, the distribution of MSH and MSL was concentrated in the range 0.005 to 0.009 MPa, TS was mainly distributed about 0.003 MPa. Von Mises equivalent stress distribution showed no significant difference.

CONCLUSIONS

The loss of tooth torque was inevitable, irrespective of which method was used to close the extraction space. However, miniscrew application and higher hooks reduced the loss of torque and avoided lingual rotation.

CLINICAL RELEVANCE

This study shows that miniscrew implants with different hooks can better control the movement of the maxillary canines. The non-invasive nature of the finite element analysis and its good simulation of dental stress and instantaneous motion trend have a clinical advantage in the analysis of tooth movement.

The Analysis of Intermolar Width and Skeletal Base Class as a Predictor of Potential Maxillary Canine Impaction in Permanent Dentition: A Cross-Sectional Study

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.

Influence of alveolar bone thickness and bucco-palatal inclination on root resorption of lateral incisors in unilateral maxillary impacted canines: a retrospective observational study

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.

Evaluation of the relationship between maxillary canine impaction with arch dimensions and maxillary sinus dimensions using Cone Beam Computed Tomography (CBCT )

Background

We aimed to evaluate the morphology of maxilla and sinus dimensions in subjects with unilaterally and bilaterally impacted canine using cone beam computed tomography (CBCT) records.

Methods

CBCT records taken during 2020-2022 of 120 patients were obtained to investigate the relationship between impacted canine and maxillary morphology as well as sinus dimensions. The CBCT images were then divided into three groups: control, unilaterally canine impaction and bilaterally canine impaction. Then morphology-related variables (arch circumference, arch length, inter molar width, inter first premolar width, palatal depth, anterior posterior dimension of the right and left sinuses, and mediolateral dimension of the right and left sinuses) were analyzed and compared between groups. All measurements were done by Ondeman 3D dental software. Statistical analysis was carried out by SPSS software version 21 using one-way ANOVA.

Results

There were meaningful differences in patients with canine impaction compared with control group in arch circumference (P value= 0.004) and arch length (P value= 0.001), inter molar width (P value= 0.001), inter first premolar width (P value= 0.001), mediolateral dimension of the right (P value=0.001) and left (P value= 0.001) sinuses of maxilla. Furthermore, Palatal depth and anterior posterior dimension of the right and left sinuses did not show statistically significant difference between groups.

Conclusion

Canine impaction can considerably affect the morphology of maxillary and sinuses dimensions. Nevertheless, future studies are needed to determine the exact structural and molecular effects of the canine impaction on maxillary sinuses and neighboring tissues.

Screening for the risk of canine impaction, what are the presumptive signs and how does it affect orthodontics? A cross-sectional study in France

PURPOSE

The treatment of impacted canines is a challenge for orthodontists. The availability of suggestive clinical signs has become crucial for treatment before the potential for evolution ceases. The main objective was to evaluate the prevalence of the suspected displaced canine (SDC) and to highlight factors easily identifiable from the oral examination.

METHODS

SDC was assessed on panoramic X-rays, on the basis of the angle with the median sagittal plane and the degree of overlap with the permanent lateral incisor. Its association with mesio-distal tooth and palate widths was assessed by univariate analysis. Next, the association of SDC with temporary tooth extraction, expansion and/or premolar extraction was considered using the same modality.

RESULTS

In this retrospective study, the records of 292 patients aged 7 to 13 years were reviewed. SDC was detected in 39% of patients i.e., 28,8% of observed canines. Reduced coronal mesio-distal diameters of permanent maxillary central incisors, 8.7 ± 0.6 mm versus 8.8 ± 0.7 mm (p < .05), and first permanent molars, 10.0 ± 0.7 mm versus 10.2 ± 0.7 mm (p < .001), as well as reduced inter-molar width, 38.7 ± 2.7 mm versus 39.4 ± 2.9 mm (p < .01), were predictive factors. SDC led orthodontists to indicate extraction of maxillary primary canines, OR = 3,32 (p < .001) or even extraction of premolars, OR = 1,66 (p < .05).

CONCLUSION

This study confirmed the interest of panoramic X-rays in detected canines at risk of SDC. Dental factors can be combined to make screening more reliable and predict impaction that makes orthodontics complex.

TRIAL REGISTRATION NUMBER

Opinion n°21.131, dated 09.21.2021, retrospectively registered.

Knowledge, attitudes, and practice of non-medical students regarding impacted teeth: a cross-sectional study

OBJECTIVES

To explore the knowledge, attitudes, and practice (KAP) of non-medical students regarding impacted teeth and the factors associated with KAP.

MATERIALS AND METHODS

This cross-sectional study enrolled non-medical students at two universities (Northeastern University and Shenyang Conservatory of Music) in northeastern China between December 2022 and February 2023. Scores > 70% were defined as adequate knowledge, positive attitudes, and proactive practice.

RESULTS

A total of 519 non-medical students participated in this study. Most participants were male (54.72%), ≤ 20 years of age (72.83%), and freshmen (36.03%). The mean knowledge score was 4.98 ± 3.46 (possible range: 0-10), indicating poor knowledge (49.80%). The multivariable analysis showed that having impacted teeth were independently associated with adequate knowledge (OR = 3.114, 95% CI: 1.589-6.103, P = 0.001). The mean attitude score was 24.65 ± 3.78 (possible range: 7-35), indicating favorable attitudes (70.43%). The knowledge (OR = 1.182, 95% CI: 1.116-1.251, P < 0.001), junior grade (OR = 0.541, 95% CI: 0.327-0.895, P = 0.017), senior grade and above (OR = 0.477, 95% CI: 0.274-0.829, P = 0.009), and a history of impacted tooth extraction (OR = 2.386, 95% CI: 1.048-5.436, P = 0.038) were independently associated with the good attitudes. The mean practice score was 21.45 ± 5.64 (possible range: 6-30), indicating positive practice (71.50%). The knowledge (OR = 1.074, 95% CI: 1.017-1.133, P = 0.010) and female (OR = 1.501, 95% CI: 1.052-2.141, P = 0.025) were independently associated with the proactive practices.

CONCLUSIONS

Non-medical students had poor knowledge but favorable attitudes and good practice toward impacted teeth. Non-medical students require additional education and awareness about the importance of early detection and management of impacted teeth.

CLINICAL RELEVANCE

The study highlights the need for improved education and awareness among non-medical students regarding impacted teeth.

Influence of the maxillary dimensions and lateral incisor anatomy on the palatal impaction of maxillary permanent canines: A three-dimensional case-control study

OBJECTIVE

The diagnosis of impacted upper permanent canines (IUPC) is a relatively common clinical finding. The aim of this study was to investigate associations between the upper permanent canines palatal impaction, lateral incisors morphology and the maxilla bone base.

MATERIAL AND METHODS

Cone-beam tomography files from 62 subjects were divided into 2 groups: impaction group (ICG/n=31; mean age 14.3±2.4) with 45 canines impacted on the palatal side and age- and sex-matched control group (CG/n=31; mean age 14.3±2.3), with 62 normally erupted canines. Linear and volumetric measurements of the lateral incisors, linear transversal measures and the maxillary anterior perimeter were taken. Independent Student's t-test was used for intergroup analysis with correction of Bonferroni.

RESULTS

Significant differences were found for crown length and root diameter (buccal-palatal) (P<0.005). The maxillary anterior perimeter in the ICG was reduced in relation to the GC but not significantly (P=0.008). The transverse skeletal variables of the maxilla were equivalent in the intergroup comparison (P>0.005).

CONCLUSION

Smaller dimensions in the crown length and in the upper permanent lateral incisors root buccal-palatal diameter were associated with the impaction of upper permanent canines on the palatal side. The maxillary transverse morphology did not show any association with the occurrence of this condition.

Rescuing the Hidden Canine: A Case Report of Successful Surgical Exposure and Orthodontic Management

Canine impaction, a recognized dental condition, particularly in the maxillary region, poses both functional and esthetic challenges. This case report explores the management of impacted maxillary canines coexisting with missing upper third molars in the same patient, showcasing the complexity of dental anomalies. Its multifaceted etiology includes complex eruption pathways and potential genetic factors. Addressing the impacted canine (upper left), particularly in the anterior region, is essential for oral health and aesthetics. Surgical-orthodontic techniques, guided eruption, and interdisciplinary collaboration have revolutionized management. This report emphasizes early diagnosis, personalized treatment, and the transformative potential of surgical exposure and orthodontic intervention in enhancing oral health, function, and aesthetics.

Influence of the maxillary dimensions and anterior teeth anatomy on the buccal impaction of upper permanent canines: A three-dimensional case-control study

OBJECTIVE

The diagnosis of impacted upper permanent canines (IUPC) is a relatively common clinical finding. The aim of this study was to investigate the association of the buccal impaction of upper permanent canines with their dimensions and the maxilla bone base.

MATERIAL AND METHODS

Cone beam computed tomography files of 66 patients were allocated into: impaction group (ICG/n=33/mean age 15.7±3.9 years), with 44 impacted canines by the buccal side; control group (CG/n=33/mean age 15.66±3.99 years), matched for age and sex, with 66 canines normally erupted. The following measurements were obtained from ICG and CG groups: linear and volumetric canine dimensions, linear measurements of upper permanent central and lateral incisors, measurements of the anterior perimeter and transverse segments of the maxilla. Independent Student's t-test was used for intergroup analysis with correction of Bonferroni (α=0,005).

RESULTS

Higher values were found in the means of the variables regarding to the anterior teeth crowns in the ICG group, however, without a significant difference (P<0,005). The upper arch anterior perimeter of the individuals with canine impaction through buccal area was reduced compared to CG (P=0.001).

CONCLUSIONS

It can be concluded that individuals with upper buccal impacted permanent canine showed a significantly smaller anterior perimeter of the maxillary arch when compared to the control group. Although greater canine mesiodistal diameter was found in this group, there is no statistical association with the occurrence of this condition.

Orthodontic Treatment of Palatally Impacted Canines in Severe Non-Syndromic Oligodontia with the Use of Mini-Implants: A Case Report

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.

Prevalence of canine impaction in the western province of Saudi Arabia: A cross-sectional survey

BACKGROUND/AIM

Canine tooth impaction could have a negative influence on the stomatognathic system and could make it difficult for clinicians to manage malocclusions. The aim of this retrospective study was to investigate the prevalence of canine impaction, which could be a cause of malocclusion, in the population in the western province of Saudi Arabia.

METHODS

A retrospective analysis of digital orthopantomograms (OPGs) of 400 patients aged 12-40 years, who are citizens of Saudi Arabia residing in the western province and who presented for treatment at the dental clinics of Batterjee Medical College, Jeddah, Saudi Arabia were included. The OPGs and dental records of these patients were reviewed for canine impaction and were categorized based on age, gender, and type of impaction.

RESULTS

The prevalence of patients that exhibited canine impaction was found to be 4%. Males had a significantly higher percentage of prevalence than females (P < 0.016), and impaction was significantly higher among patients aged below 18 years (P < 0.001). Moreover, the most commonly observed impaction was mandibular canine impaction (87.5%).

CONCLUSIONS

Prevention of malocclusion and maintenance of a normal dentition (better aesthetics and chewing) necessitates early detection of impacted canines.

Orthodontic input in the management of hypodontia cases

This article aims to give an overview of the part orthodontics plays in the management of hypodontia cases. Severity of hypodontia varies and some cases can be managed by orthodontics alone. The more complex cases benefit from multidisciplinary care with a combination of orthodontics and restorative treatment. This article sub-divides orthodontic involvement in hypodontia cases into three distinct phases, while providing clinical examples to highlight the management of a variety of cases ranging from simple to complex.

Maxillary Impacted Canine and Upper Lateral Incisor Agenesis Treatment with "Canine First Technique" and Clear Aligners: A Case Report

The aim of this study was to show a case of an impacted canine in an adult patient with agenesis of the maxillary lateral incisor treated with clear aligners (CA). A 19-year-old male with a persistence of 5.3 and absence of 1.2 came to our department of the School of Orthodontics at the University of Federico II in Naples and asked for an aesthetic treatment. The Canine First approach was used to surgically expose the canine and pull it into the dental arch. In order to ensure long-term aesthetic, periodontal, and occlusal results, a treatment with CAs to close the space through the mesial placement of the canine and the enameloplasty of the tooth crown was performed. At the end of the treatment, the occlusal objectives were achieved.

Root Resorption of the Permanent Central Incisor through Ectopic Eruption of the Maxillary Canine

Although ectopic eruption of the maxillary canine has a low prevalence, a late diagnosis can have serious consequences. A careful clinical examination, assisted with radiographic examination, ensures early diagnosis, facilitates planning, and minimizes possible adverse consequences. This study reports a case of ectopic eruption of the permanent maxillary canine, with complete root resorption of the central permanent incisor, the consequences of which caused functional, aesthetic, and psychological harms to the patient. The procedures used included canine ectopic remodeling of the ectopic canine in the central incisor and orthodontic correction, which treated the anomaly and rebuilt the patient's self-esteem.

Investigation of the Relationship of Impacted Maxillary Canines with Orthodontic Malocclusion: A Retrospective Study

Impacted canines, which play an important role in smile aesthetics and functional occlusion, can lead to dental and skeletal malocclusions. In this study the aim was to evaluate the relationship between impacted maxillary canines and malocclusion. A total of 151 patients comprising 101 females and 50 males aged between 13 and 33 years were included. The groups were divided based on age, gender, skeletal and dental classification, and sector classification. Angular and linear measurements were performed on lateral cephalometric and panoramic radiographs. In panoramic radiographs, the vertical distance of the impacted canine to the occlusal plane and the angle between it and the bicondylar plane were measured and sector classification was performed according to its relationship with the root of the lateral incisor. Skeletal classification was performed according to the ANB angle on lateral cephalometric radiographs and dental classification by molar relationship via the intraoral photographs. The Chi-square test analyzed independent qualitative and quantitative data using Kruskal-Wallis and Man-Whitney U tests. The statistical significance level was accepted as p < 0.05. According to the intraclass correlation test, an excellent positive correlation was found with 0.985 for canine distance and 0.993 for canine angle between the repeated measurements. The impaction of the maxillary right canine was significantly highest in females and lowest in males. The impacted canine angle was significantly highest in sector 1 and lowest in sector 4. Distance to the occlusal plane was significantly higher in dental Class II and sector 4. It was observed that there was a considerable relationship between impacted maxillary canines and malocclusion; bilateral impacted canines were more frequent in skeletal Class III, and the distance of impacted canines to the occlusal plane increased while their angles decreased both in dental Class II and from sectors 1 to 4.

Association between maxillary canine impaction and other dental anomalies: radiological study of a mixed dentition children's cohort from an orthodontic clinic

PURPOSE

To investigate the significance of association between maxillary impacted canines and various dental anomalies.

METHODS

Files of 874 orthodontic patients were evaluated for the presence of maxillary impacted canines. From this sample, a group of 97 patients (39 males and 58 females) with at least 1 impacted maxillary canine consisted the study group. This group was compared to a control group of 97 patients (42 males and 55 females) that was created by random selection from the initial sample without maxillary canine impaction. The impaction diagnosis was made from the panoramic radiographs. Chi-square test was used to perform the analysis for significant associations. Stepwise discriminant analysis, binary logistic regression and classification tree were used to identify best combinations.

RESULTS

Statistically significant difference was found for peg-shaped maxillary lateral incisors and infraoccluded deciduous molars. The presence of peg-shaped upper lateral incisors arises the probability of impacted canine to 83.3%, a distal displaced unerupted second premolar to 63.16% and the impaction of any other teeth to 80% as showed by the classification tree.

CONCLUSIONS

The presence of peg-shaped maxillary lateral incisors and infraocclusion of deciduous molars can be considered major valuable early risk indicators for maxillary canine impaction, because they manifest before the maxillary canine eruption. Special consideration should be given on distal displaced unerupted second premolar and the impaction of any other teeth. Patients with these dental anomalies are candidates for future interceptive treatment for canine eruption.

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.

An Orthodontic Approach for the Correction of Transposition along with Multiple Impacted Teeth

Impaction of teeth affects patients' esthetics, speech, and masticatory efficiency. In addition, the transposition of teeth makes a case difficult to manage. This case report describes a case of a 14-year-old boy with the impaction of the maxillary right central incisor and canine along with the transposition of the right canine and lateral incisor. The impacted teeth were surgically exposed and guided into the arch using orthodontic traction. Likewise, the transposition was corrected orthodontically by moving the teeth to their desired position without any detrimental effect on the adjacent teeth. The patient's esthetics and occlusion improved substantially after the orthodontic intervention.

Comparison of root apex's position between unilateral and bilateral palatally impacted canines: A pilot study

INTRODUCTION

The purpose was to determine whether the location of the root apices of unilateral palatally impacted canines differs from that of bilateral palatally impacted canines using cone-beam computed tomography.

METHODS

The subjects were divided into 3 groups: a bilateral palatally impacted canine group (BPG; n = 28), a unilateral palatally impacted canine group (UPG; n = 28), and a control group (CG; n = 28) that included contralateral normally erupted canines in the UPG. After selecting the root apex in the onDemand3D program, 3-dimensional coordinates were extracted. These 3-dimensional coordinates were converted using the MATLAB program to 2-dimensional coordinates via projection on the palatal plane. Procrustes analysis was used to superimpose these 2-dimensional coordinates. The x- and y-coordinates of the root apices were used to measure the distance between the origin and root apex.

RESULTS

The distance between the root apex of the canine and the origin was 17.43 ± 1.78 mm in BPG, 17.96 ± 1.87 mm in UPG, and 13.96 ± 0.95 mm in CG. There was no statistically significant difference between UPG and BPG. However, there was a statistically significant difference between the CG and impacted groups (UPG and BPG). The same results were found for the x- and y-coordinates.

CONCLUSIONS

The location of the root apices of unilateral palatally impacted canines is similar to that of bilateral palatally impacted. The location of root apices of palatally impacted canines differs from that of normally erupted canines.

Unilateral vs Bilateral Maxillary Canine Impaction: A Cone-Beam Computed Tomography Study of Patterns and Associations

AIM

This retrospective study aimed to compare and evaluate the pattern of maxillary canine impaction and its association with other anomalies using cone-beam computed tomography (CBCT).

METHODS

A total of 59 CBCT records of patients (ages 12 and up) were divided into two groups: A total of 35 subjects with unilateral canine impactions and 24 subjects with bilateral canine impactions. The CBCT data were analyzed for the measurement of qualitative and quantitative variables.

RESULTS

In unilateral canine impaction, the mesiodistal (MD) width of the central incisors and the nasal cavity (NC) width were wider (p < 0.05). The canine-palatal plane (U3-PP) distance was significantly longer in bilateral canine impaction (p < 0.05). The distance of the impacted canines from the palatal and mid-sagittal planes, the anterior dental arch width, and the maxillary skeletal width changed significantly with the position of the impacted canines (p < 0.05). Males had 0.185 odds of presenting with a bilateral canine impaction as compared to females (p = 0.025). The odds of having bilateral canine impaction with a longer canine-midsagittal plane (U3-MSP) distance was 1.30 (p = 0.003).

CONCLUSION

The findings indicate a gender predilection with females showing a greater prevalence of bilateral canine impaction. Supernumerary teeth were associated with unilateral impacted canines and lower canine impaction with bilaterally impacted canines.

CLINICAL SIGNIFICANCE

Anomalies in the form of the maxillary central and lateral incisors, distance from the maxillary canine to the palatal plane and the mid-sagittal plane, NC width, maxillary skeletal width, and gender, are the best discriminating parameters between unilateral and bilateral canine impactions.

The labiopalatal impacted canine: Accurate diagnosis based on the position and size of adjacent teeth: A cone-beam computed tomography study

INTRODUCTION

Labiopalatal impacted canines (L-PICs) occur when the canines lie between central and lateral incisors, with their tip palatal to the central incisor and part of their crown labial to the lateral incisor. Because of their unusual position, they are often misdiagnosed, and their orthodontic resolution fails. This study aims to provide clinicians with pathognomonic features for early and accurate positional diagnosis of L-PICs.

METHODS

The L-PIC sample included 21 subjects with full diagnostic records. The control group of normally erupted canines was taken from a previous study. Clinical photographs, 2-dimensional radiographs, and cone-beam computed tomography were used to evaluate the positions of the adjacent incisors and first premolars, the canine incisor index, and the mesiodistal width of the lateral vs central incisors.

RESULTS

Central incisors adjacent to L-PICs showed significant mesial root angulation, labial root inclination, and mesiolabial crown rotation, whereas lateral incisors presented significant distal root angulation, palatal root inclination, and mesiolabial crown rotation, in comparison to controls. The roots of the central and lateral incisors were divergent, in contrast to the controls, in which they were slightly convergent. The first premolar positions were not affected. The mean canine incisor index was significantly bigger in L-PICs vs the controls, suggesting a palatal canine. The lateral incisor widths were similar between the groups.

CONCLUSIONS

This study provides the orthodontist with evidence-based clinical and radiographic red flags for diagnosing L-PIC, which may allow timely initiation of orthodontic treatment and correct planning of mechanotherapy.

Root morphology of lateral incisors adjacent to impacted maxillary canines: A cone-beam computed tomography retrospective cross-sectional study

INTRODUCTION

To compare the root morphology of the maxillary lateral incisors (MLIs) adjacent to an impacted (IMC) versus non-impacted maxillary canine (non-IMC).

MATERIALS AND METHODS

This cross-sectional study included cone beam computed tomography (CBCT) images derived from 154 subjects (with unilateral/bilateral impacted maxillary canines or without canine impaction). Each MLI was considered as a unit of analysis. Thus, the study group included 122 MLIs adjacent to impacted maxillary canine (IMCG) and the control group included 122 MLIs adjacent to a non-impacted maxillary canine (CG). Groups were matched by age, sex and evaluation side. Root length, root dilaceration angle and root convergence angle were evaluated in both the coronal and sagittal planes. Comparisons between groups were made with Student's t-test and the chi-square test with Bonferroni correction (P<0.008, P<0.01, respectively).

RESULTS

The root measurements of the MLIs showed some significant differences between the groups. The coronal root length was 0.52mm shorter but not highly significant (P=0.032), the coronal root dilaceration angle was 7.51° smaller (P<0.001), and the coronal root convergence angle was 1.28° greater (P<0.001) in the IMCG compared to the CG. The orientation of root dilaceration in the MLIs showed significant differences between the groups: it was mostly distopalatal in the GC (87.5%), to a lesser extent in the IMCG (58.9%) and also mesiopalatal in the IMCG (22.3%), (P=0.001).

CONCLUSIONS

The root morphology of MLIs adjacent to an IMC showed a tendency of shorter length, smaller root dilaceration and greater root convergence in the coronal section than MLIs adjacent to a non-IMC.

Radiographical characteristics and traction duration of impacted maxillary canine requiring surgical exposure and orthodontic traction: a cross-sectional study

This cross-sectional study aimed to classify the radiographical characteristics of impacted maxillary canines that were surgically exposed following orthodontic traction and to find out which factor is most closely related to traction duration. This study enrolled 74 patients with 87 maxillary canines. Cone-beam computed tomography images, panoramic radiographs, and medical records were analyzed. Cystic-appearing lesion and resorption of adjacent roots were observed in 26.4% and 23.0% of cases, respectively. Impacted maxillary canines were mostly distributed in the lateral incisor area. The mean (± standard deviation) traction duration for the 47 teeth that met the study criteria was 13.9 (± 8.9) months. Impacted maxillary canines treated with surgical exposure and orthodontic traction showed increasing possibilities of palatal impaction and resorption of the adjacent root as they were located mesially (p < 0.05). The distance from the occlusal plane to the impacted maxillary canine showed the strongest positive correlation with traction duration (r = 0.519, p < 0.01). When establishing treatment plans for patients with impacted maxillary canines, distance from the occlusal plane to the impacted canines, rather than the angle, should be considered in predicting the duration of treatment.

The Stability Guided Multidisciplinary Treatment of Skeletal Class III Malocclusion Involving Impacted Canines and Thin Periodontal Biotype: A Case Report with Eight-Year Follow-Up

Skeletal class III malocclusion with severe skeletal disharmonies and arch discrepancies is usually treated via the conventional orthodontic-surgical approach. However, when associated with tooth impaction and periodontal risks, the treatment is more challenging and complex. The esthetic, occlusal, and periodontal stability of the treatment outcome is more difficult to obtain. The 16-year-old female patient in this case was diagnosed with dental and skeletal Class III malocclusion, bilateral impacted maxillary canines, and scalloped thin gingiva. The multidisciplinary management included a segmental arch technique, extracting two premolars, a subepithelial connective tissue graft surgery, and orthognathic surgery. The esthetic facial profile, pleasant smile, appropriate occlusion, and functional treatment results were obtained and maintained in 8-year follow-up.

Relationship between palatally impacted canines and dimensions and morphology of sella turcica: A cone-beam computed tomography study

INTRODUCTION

This study aimed to analyze the association of unilateral and bilateral palatal canine impaction with the dimensions and morphology of sella turcica from 3-dimensional cone-beam computed tomography (CBCT) images.

METHODS

CBCT images of patients with bilateral (BPI) (n = 12; 9 female 3 male; 20.75 ± 5.88 years) and unilateral (UPI) (n = 35; 22 female 13 male; 19.28 ± 5.57 years) palatally impacted canines were compared with a control group (n = 56; 34 female 22 male; 20.82 ± 4.88 years). Linear measurements regarding sella turcica were made, and its morphologic variations were categorized. Two group comparisons were made with the Student t test or Mann-Whitney U-test, whereas one-way analysis of variance or Kruskal-Wallis tests were used for multiple group comparisons. Categorical variables were compared using the chi-square or Fisher exact test as appropriate. The binary logistic regression analyses and correlations using Spearman or Pearson correlation analyses were used to determine associations between variables (P <0.05).

RESULTS

Sella diameter was significantly smaller in the BPI group compared to UPI and control groups. There was a significant association between sella diameter and BPI when compared with the control group (χ2[1] = 9.150; P = 0.008). There were no significant differences between groups in the distribution of sella turcica morphology.

CONCLUSIONS

Despite the similar genetic origin of the sella turcica region and teeth, the association of palatal canine impaction with dimensions and morphology of sella turcica was weak. Both local and genetic factors might contribute to the ectopic position of the canine.

Traction of impacted and stacked maxillary anterior teeth with precise biomechanics followed by torque control using gate spring

Impaction of multiple maxillary anterior teeth is a rare condition; when it occurs, it impacts the patient's chewing function and smile esthetics, and it has always been problematic for clinicians. This case report presents an 11-year-old girl with impaction of 3 adjacent maxillary anterior teeth, including labiopalatally oriented maxillary right central and lateral incisors and a mesially inclined maxillary right canine. These 3 impacted and stacked teeth were sequentially aligned after surgical exposure and orthodontic traction, and the surrounding dentigerous cyst healed simultaneously. Precise and delicate biomechanics will control root movement and prevent root collision. Gate spring, a novel torquing auxiliary, was used for highly efficient root torque movements of the previously impacted incisors. After 32-month treatment, the patient's occlusion and esthetics greatly improved.

“Canine First Technique”, An Innovative Approach in Maxillary Impacted Canines: A Case Report

Background:

Maxillary canine impaction is one of the most challenging issues in orthodontics. The best treatment protocol in these cases is still debated. The purpose of this study is to describe the management of maxillary canine impaction in an adult female patient with the “Canine First Technique”.

Case Report:

A 21-years-old female attended our dental unit seeking orthodontic treatment. Clinical examination revealed a class II relationship, the persistence of both upper deciduous canines. The panoramic X-ray and Cone Beam Computed Tomography showed bilateral palatal permanent canine displacements and close proximity between crowns of impacted canines and roots of lateral incisors. The canines were disimpacted by means of two cantilevers inserted directly in two Temporary Anchorage Devices placed palatally and when canines were near the crest, the fixed orthodontic treatment was started.

Results:

At the end of the treatment, canine Class I relationships with torque correction of canines, normal overjet and overbite, and good alignment of dental arches were achieved. The radiographic evaluation showed ideal root parallelism and preserved periodontal health in the canine region.

Conclusion:

The Canine First Technique could provide some advantages compared to conventional approaches in terms of biomechanics, esthetics, oral hygiene, and risk reduction of root resorption of upper lateral incisors.

Impacted Palatal Canines and Diode Laser Surgery: A Case Report

INTRODUCTION

Maxillary canine is the most frequent dental element that could likely remain impacted in the bone structure, with a percentage between 1 and 5%. This study presents a case report using a diode laser for surgical-orthodontics disinclusion of a palatal mucosal impacted permanent left upper canine (2.3) and the simultaneous application of an orthodontic bracket.

METHODS

After cementation of the trans-palatal bar to the upper first molars with a hook for orthodontic traction, local anaesthesia with articaine was performed, followed by surgical operculectomy using a diode laser (810 nm wavelength, continuous wave mode with a power output of 3 W, and a 0.4 mm diameter optical fiber), and the orthodontic bracket with a passive metal looped ligature was applied. Subsequently, active elastic traction was applied on 2.3 and the upper arch was bonded for the application of a series of orthodontic wires, lace-back, and metal ligatures. A progressive reactivation of the elastic traction and extraction of 6.3 was necessary to translate the canine into the correct arch position.

RESULTS

Diode laser surgical-orthodontic disinclusion of impacted upper canine was performed successively, resulting in a dry surgical field ideal for orthodontic bracket adhesion. No pain and no swelling have been reported from the patient. The orthodontic treatment allowed the canine to be moved to the correct position in the arch.

CONCLUSIONS

This case showed that the diode laser is a valid alternative for the surgical-orthodontic disinclusion of an included tooth element.

Risk Prediction of Maxillary Canine Impaction among 9-10-Year-Old Malaysian Children: A Radiographic Study

BACKGROUND

Early diagnosis and interceptive treatment of the maxillary canine impaction is crucial as it reduces treatment complexity and decreases complications and adverse outcomes. Aim and Objectives. To determine the mean maxillary canine position among 9-10-year-old children and predict the risk of impaction of the maxillary canines. Methodology. Panoramic radiographs (PANs) of 289 healthy children aged between 9 and 10 years were observed where the average position of maxillary canines was related to the lateral incisor, sector locations, and angulations to the bicondylar line were traced. The average position was obtained by using descriptive statistics. One sample Wilcoxon signed-rank test is done to predict the risk of canine impaction by comparing the data obtained to the average position from prior studies.

RESULTS

A total of 289 PANs (126 males and 163 females) were utilized for the analysis. The findings showed that the average position of the maxillary canines in our population was statistically different from the average position of nonimpacted canines in previous studies. However, on average, more than 85% of canines in our population were still located within the safe range of satisfactory position, with females showing slight predominance outside of the acceptable range. The mean scores of the angles between the right canine and lateral incisor were significantly higher among females than males (p = 0.001). Similarly, females had a significantly higher mean angle of the left canine than males (p < 0.001). In regard to the angles between the bicondylar line and permanent maxillary canine, the mean scores were not significantly different (p > 0.05) on both the left and right side.

CONCLUSION

There is a low risk of impaction of maxillary canines in the Malaysian population. However, more retrospective studies using more radiographic and clinical indicators need to be done to confirm the risk of impaction further.

A Modified Hyrax-Type Expander Is Effective for Distal Bodily Movement of the Maxillary First Molar

Impaction and eruption disturbance of permanent teeth are frequently encountered in orthodontic practice. The canine teeth play an important role both functionally and esthetically. Eruption disturbance of a maxillary canine, if left untreated, can cause not only disturbed jaw movement and esthetic problems, but also root resorption of adjacent permanent teeth, and thus should be diagnosed and treated appropriately. In this report, we present a case of a patient with eruption disturbance of the maxillary left canine in which the maxillary left second molar was extracted and the maxillary left first molar was distally moved with a Hyrax-type expander (Veltri Monolateral Screw®; Leone, Firenze, Italy) designed to enable the distal movement of a unilateral first molar in order to create eruption space for the maxillary left canine, resulting in smooth distal molar movement and alignment of the left maxillary canine in the dental arch. Furthermore, the maxillary third molar was also aligned to achieve a good occlusal relationship without reducing the number of teeth.

Volumetric Evaluation of Maxillary Lateral Incisor Root Resorption due to Positional Variations of Impacted Canine

Introduction

The purpose of this study was to investigate the relationship of the volume of lateral incisor resorption and impacted canine features.

Materials and Methods

This study consisted of CBCT images of 47 samples with unilateral impacted maxillary canine (13 males and 34 females). The volume of lateral incisors in impacted side and nonimpacted side was calculated with the Mimics 10.01 software. Canine and lateral incisor angulations were measured in panoramic reformatted images. The canine cusp tip distance from midpalatal suture was measured in axial cross-section images.

Results

The difference between two sides volume was considered as the mean volume of resorption (MVR) that was statistically significant (P < 0.001). MVR was not statistically significant between two sexes (P=0.95), in buccopalatal and mesiodistal positions of impacted canine, and in different angulations or distances of the impacted canine to midline (P > 0.05). The concurrent effect of the canine distance to the midline and the angle of the canine with the lateral incisor on the MVR were statistically significant (P=0.049).

Conclusion

The maximum rate of lateral root resorption is when the distance from the canine to the midline is less than 5 mm and the angle of the canine to the lateral incisor is 30–60 degrees.

Predictive factors associated with adjacent teeth root resorption of palatally impacted canines in Arabian population: a cone-beam computed tomography analysis

BACKGROUND

This study aimed to evaluate three-dimensionally the factors associated with adjacent teeth root resorption of palatally impacted canines.

METHODS

In this retrospective cross-sectional study, one-hundred and fourteen cone beam computed tomography scans with palatally impacted maxillary canines were evaluated for the presence of adjacent root resorption. Seven parameters were analyzed: alignment of maxillary incisors, presence of deciduous canines, first premolars' roots configuration, impacted canines rotation, angulation of impacted canine to the midline, contact relationship, and area of contact with adjacent teeth. The association between dependent and independent qualitative and quantitative variables was analyzed using chi-square and independent student's t-test, respectively. The multivariate analysis was performed using regression analysis. The significant value was set at P ≤ 0.05.

RESULTS

The overall incidence of vertical, horizontal impaction and adjacent root resorption were 92, 8 and 77.2%, respectively. The apical third was the most involved area (57%); resorption of a single tooth was found in 21.9% of the total sample. The most common resorbed teeth were lateral first premolars (24.6%), followed by central lateral incisors (20.2%), and lateral incisors (15.8%) of the total sample. The severity of resorption was highest in grade I (31.5%) and lowest in grade III (7.6%). Three variables showed significant differences between resorption and non-resorption groups namely; canine rotation (P < 0.013), contact relationship (P < 0.001), and area of contact with adjacent teeth (P < 0.001). Regression analysis revealed an association between adjacent root resorption and permanent canine rotation, adjacent premolars' roots configuration, contact relationship, and area of contact (P < 0.05).

CONCLUSION

Two-thirds of impacted maxillary canines showed a form of root resorption. The most commonly resorbed tooth was the lateral incisors while the least affected one was the central incisors with apical one-third being of the highest risk. The predisposing factors including the canine rotation, premolar with separated roots, contact relationship, and area of contact with adjacent teeth are to be considered for any interceptive treatment.