Root resorption associated with ectopically erupting maxillary permanent canines: a computed tomography study

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.

Interdisciplinary management of maxillary incisors with root resorption caused by impacted canines: A case report

The aetiology of impacted canines is multi-factorial. Several theories have been proposed, such as lack of space, genetic predisposition, physical barriers like supernumerary teeth, odontomas and other conditions that interfere with the eruption pathway. One of the main complications that can be generated by impacted canines is the resorption of the root of the adjacent teeth. This case report examines the importance of interdisciplinary management of maxillary incisors with root resorption caused by impacted canines in a 13-year-old male patient. Careful traction of impacted canines and proper tissue management followed by space closure and retroclination of anterior incisors with orthodontic treatment. Finally, functional and aesthetic results using dental veneers for oral rehabilitation allowed the patient to obtain favourable results.

A Retrospective Study of Ectopic Eruption in 35 Dogs

Ectopic eruption results from a disturbance in tooth development and eruption, leading to an erupted or non-erupted tooth being in an unexpected anatomical location. This retrospective case series describes the location, position, form, and clinical signs associated with ectopic eruption in dogs. Thirty-five dogs (46 teeth) were diagnosed with ectopic eruption at three clinical practices during 2017-2020. The cases were described in terms of the location, the development and eruption status, the clinical signs, the consequences, and the treatment performed. The collected data were statistically analyzed to establish possible ramifications. The results showed that the ectopic eruption in the evaluated cases involved permanent teeth, mainly located in the maxilla, and mostly unerupted. Those located in the mandible were significantly more impacted than those located in the maxilla. This study concluded that tooth crowding and malocclusion (39.1%), facial swelling (8.6%), and periodontal disease (8.6%) were associated with the presence of ectopic eruption, and consequently, treatment was required in the majority (65.2%) of cases.

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.

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.

Root Resorptions on Adjacent Teeth Associated with Impacted Maxillary Canines

Aim: Through the use of CBCT images, many unidentified features of impacted canines can be easily resolved. The potential collision of impacted maxillary canines and adjacent teeth could lead to root resorption (RR). The aim of this study is to examine the prevalence, location and severity of RR on adjacent teeth caused by impacted maxillary canines and the association between the adjacent teeth and the features of maxillary impacted canines on CBCT. Methods: This study examined 89 subjects with 108 maxillary impacted canines, having had no previous orthodontic treatment (mean age: 18.3 ± 4.1 years). The following impacted-canine-related parameters were analyzed on the CBCT images: location; RR levels on adjacent teeth; occlusal line and midline distances of impacted canines; and the angulations of impacted canines to the midline, lateral incisor and occlusal line. Logistic regression was used to evaluate the association between RR and the measured parameters on CBCT. Results: In this study, we found that the majority of our patients with impacted maxillary canines were female (62.5%). Of the total 108 maxillary impacted canines, 60.2% resorbed the adjacent teeth of the affected quadrants. Lateral incisors were the most affected (34.3%). The mean age of subjects with RR was 16.7 ± 3.5 years. The frequency of RR was statistically significantly higher in female subjects (40.4%). Slight RR was the most frequent (30.5%) and the highest incidence noted at the apical third of the root (29.6%). Regarding the impacted maxillary canine angulation to the midline and adjacent tooth, higher values of angulation caused severe forms of RR (p < 0.05). Conclusion: The sensitivity of CBCT allows for the accurate diagnosis of the location and the degree of RR, alongside the angulation and distance of impacted canines to adjacent teeth. The association between the linear and angular features of the impacted maxillary canines and RR was confirmed.

Root Resorption of Adjacent Teeth Associated with Maxillary Canine Impaction in the Saudi Arabian Population: A Cross-Sectional Cone-Beam Computed Tomography Study

This study aimed to identify the location of root resorption in relation to an impacted maxillary canine and grade its severity using cone-beam computed tomography (CBCT) in the Saudi Arabian population. Materials and Methods: CBCT scans of 169 patients with maxillary canine impaction were evaluated. The location and the severity of root resorption of the affected tooth in relation to the impacted maxillary canine were recorded for each patient. Results: a total 204 impacted maxillary canines caused root resorption in 218 adjacent teeth. Maximum root resorption was present in 63.3% of the apical one-third of the root and 37.6% of the palatal surfaces. There was mild root resorption in 55%, moderate in 10% and severe in 35%. There was no statistically significant difference between the gender, age, type of impaction, side of impaction, and the number, location, or degree of root resorption. Multiple logistic regression models showed significant association (p = 0.024) between gender, type of impaction, and root resorption. A significant correlation was found between the level and the surface of the root resorption (p = 0.018). Conclusion: In the Saudi population, apical one-third root levels and palatal surfaces were primarily involved in root resorption caused by impacted canines. The females with bilateral canine impaction were more likely affected by root resorption.

Location and severity of root resorption related to impacted maxillary canines: a cone beam computed tomography (CBCT) evaluation

Background

The present investigation was designed to determine the location and severity of root resorption associated with impacted maxillary canine teeth using cone beam computed tomography (CBCT). A secondary aim was to identify possible influencing factors.

Methods

The radiological reports of 183 patients, radiographed with a small-volume CBCT focussed on the impacted maxillary canine teeth, were assessed. Eighty-five patients had resorption associated with the impaction. The CBCT image datasets were viewed to determine the location and severity of the lesions.

Results

A total of 110 impacted maxillary canine teeth resorbed 120 adjacent teeth, including 14 premolars and one permanent molar. The apical third and palatal surface were commonly involved. Fifty per cent of the resorptive lesions were mild, 20% moderate and 30% severe. There was no significant relation between age or gender on the number, location or severity of resorption. There was a statistically significant correlation between the number of impacted canine teeth and the number of teeth resorbed, as well as the tooth type and the surface involved in the resorption.

Conclusions

All root levels and surfaces of teeth associated with impacted maxillary canine teeth can be resorbed to different levels of severity. Neither age nor gender influences the number, location or severity of the resorption.

Welsh dental trainees' confidence and competence in completing orthodontic assessments and referrals

OBJECTIVE

To improve the confidence and competence of newly qualified dentists in Wales in undertaking orthodontic assessments and making orthodontic referrals.

DESIGN

Quality improvement project.

SETTING

Study days arranged by the Wales Deanery.

PARTICIPANTS

The 2018-2019 cohort of dental foundation trainees (DFTs) and dental core trainees (DCTs) in Wales.

METHODS

Data were collected prospectively between January and February 2019 utilising a 20-item questionnaire based around knowledge and clinical ability in orthodontic assessment and referrals (Stage 1). In May 2019, the trainees were provided with an e-learning package tailored to the results of the clinical questions and the feedback received in Stage 1. After this, trainees repeated the questionnaire with a simplified Index of Orthodontic Treatment Need (IOTN; Stage 2).

RESULTS

There was increased self-reported confidence in 'conducting orthodontic assessments' from 67% to 95% and 'competence in completing orthodontic referrals' from 81% to 92%. At baseline, this cohort were only able to correctly determine dental age and orthodontic treatment need for 40.7% (mean) of the presented linical cases. Following the teaching intervention, this was improved with an average of 70.9% of clinical cases answered correctly.

CONCLUSION

Despite the noted improvement in the self-reported confidence and competence in undertaking orthodontic assessments and referrals in this cohort, there is still room for improvement. Hands-on orthodontic experience during dental training improved the self-reported confidence and competence with assessments and referrals. The results of this quality improvement project emphasise the need for regular continuing professional development in the field of orthodontics to maintain competence in utilising IOTN and referring appropriately.

Root Resorption of Teeth Adjacent to Untreated Impacted Maxillary Canines: A CBCT Study

Objectives

The aim of this retrospective study was to determine the position of the impacted maxillary canine (IMC) and then to inspect the frequency, location, and extent of the consequent root resorption (RR) of the adjacent teeth by using CBCT.

Materials and Methods

Forty-one patients aged 12-68 who have 56 IMC detected on CBCT images were retrospectively examined in 3D. The canine position was determined by assessing the side of impaction, buccopalatal location, the distance of the canine cusp tip to the midline and to the occlusal plane, and canine angulation to the midline. RR of adjacent teeth was analyzed by investigating the nearest location of ectopic canine to adjacent teeth in horizontal and vertical dimensions in addition to measuring the degree of RR.

Results

Twenty-seven (48.2%) impacted canines were on the right side, and 29 (51.8%) were on the left. Most of these teeth 31 (55.4%) were located palatally, while buccal impaction was seen in only 13 (23.2%) canines and 12 (21.4%) were located centrally. The mean distance of the ectopic canine cusp tip to the occlusal plane was significantly higher in males (14.4 mm) than in females (10.7 mm). RR was seen in 9 central incisors (31.03%) and 21 lateral incisors (41.17%) as well as one case in the first and second premolar. This RR was slight for all the adjacent central incisors and premolars.

Conclusions

IMC is more frequent in females, palatally and apically. When left untreated, it may cause RR of some of the adjacent teeth with various degrees, however, with no gender preference.

Prevalence and risk factors of root resorption of adjacent teeth in maxillary canine impaction, among untreated children and adolescents

OBJECTIVES

The aim of this retrospective study was to assess in maxillary canine impaction cases both the prevalence of root resorption of adjacent teeth among untreated children and adolescents, and its associated risk factors.

SUBJECTS AND METHODS

Sixty subjects (mean age 12.2 years; SD 1.9; range 8-17 years) with 83 displaced maxillary canines and without any past or ongoing orthodontic treatment were included in this study. The presence of root resorption was evaluated on images from a single cone beam computed tomography (CBCT) unit. Potential risk factors were measured on the CBCT images and on panoramic reconstructions of the 3D data sets. The sample was characterized by descriptive statistics and multiple logistic regressions were performed to predict root resorption.

RESULTS

Root resorption of at least one adjacent tooth was detected in 67.5 per cent of the affected quadrants. It was found that 55.7 per cent of the lateral incisors, 8.4 per cent of the central incisors, and 19.5 per cent of first premolars were resorbed. Of the detected resorptions, 71.7 per cent were considered slight, 14.9 per cent moderate, and 13.4 per cent severe. Contact between the displaced canine(s) and the adjacent teeth roots was the only identified statistically significant risk factor, all teeth being considered (odds ratio [OR] = 18.7, 95% confidence interval: 2.26-756, P < 0.01). An enlarged canine dental follicle, a peg upper lateral, or an upper lateral agenesis were not significantly associated with root resorption of adjacent teeth, nor were age nor gender.

CONCLUSIONS

Root resorption of adjacent teeth was detected in more than two-thirds of a sample of sixty untreated children and adolescents.

Correlation between skeletal development and maxillary canine eruption

Aim

The aim of this study was to find a correlation between the permanent maxillary canine eruption and the cervical vertebral maturation index (CVMI).

Materials and Methods

145 subjects (73 male and 72 female) in the age of 7-14 years were examined radiographically with lateral cephalographs and orthopantomographs. The CVM patterns were evaluated on the lateral cephalograph using the classification of Hassel and Farman. The stage of the permanent maxillary canine eruption has been investigated on the orthopantomographs depending on its vertical height in relation to the adjacent incisor. Descriptive statistics were obtained for both CVMI stages and canine eruption grading. Spearman rank correlation test was used to determine the correlation between both methods. The minimum level of significance was considered less than 0.05 (P < 0.05).

Results

Results showed a strong correlation between CVMI and the grading of the maxillary canine eruption in both female and male and the (r) value estimated was 0.862 and 0.758, respectively. Over 90% of deceleration stage of CVMI in both genders show canine eruption (pubertal growth spurt) about 91.66% for female and 95.65% for male and a small percentage of delay eruption 8.33% and 4.35% in female and male gender, respectively, with a predilection to the female gender.

Conclusions

A significant correlation between the permanent maxillary canine eruption stages and skeletal maturity was found. The eruption of maxillary canine occurs before the end of pubertal growth. Any delay in the eruption of maxillary canine after the deceleration stage of CVMI, suggesting a chance of impaction.

Comparative analysis of panoramic radiography and cone-beam computed tomography in treatment planning of palatally displaced canines

INTRODUCTION

The objective of this research was to compare the predictive value of panoramic radiographs (PRs) and cone-beam computed tomography (CBCT) scans for the estimation of root resorption, spontaneous eruption of a canine, and time for orthodontic traction.

METHODS

CBCT scans and PR images of 88 patients (27 male and 61 female; aged between 11 and 44 years) with 106 palatally displaced maxillary canines were retrieved from a database. Predictive values of several radiographic parameters, including the 3-dimensional angle of the canine, were analyzed using the area under the curve and multiple regression analysis.

RESULTS

The angle to the midline and canine position category had a discriminative ability for root resorption of the central incisors with area under the curve values of 0.63 (95% confidence interval, 0.56-0.79) and 0.83 (95% confidence interval, 0.75-0.91), respectively. PR measurements were not reliable predictors of resorptions, except severe resorptions, of the lateral incisors and the premolars. The measurements describing the position of the canine in relation to the midline could predict spontaneous eruption of the canine, regardless of the imaging method. The canine angle to the midline assessed on CBCT was significantly associated with traction time of the canine, producing the following equation: canine traction time = 49.6 - 0.24 × canine angle to the midline (r² = 0.360).

CONCLUSIONS

Only severe resorptions of roots can be predicted with PRs. The use of CBCT is indicated in cases of impacted canines.

To what extent are impacted canines associated with root resorption of the adjacent tooth?: A systematic review with meta-analysis

BACKGROUND

The authors' aim in this systematic review was to evaluate to what extent impacted canines are associated with root resorption (RR) of the adjacent tooth by using cone-beam computed tomography.

METHODS

The authors performed an open-ended electronic search of the Cochrane Library, Latin American and Caribbean Health Sciences Literature, PubMed (MEDLINE), Scopus, and Web of Science and a partial gray literature search by using Google Scholar, Open Grey, and ProQuest. The authors included studies in people (adolescents, adults, and older adult) with impacted maxillary permanent canines in which the investigators assessed the incidence of RR in adjacent teeth. The investigators detected RR by using cone-beam computed tomography. Two reviewers independently performed the study selection, data extraction, and risk of bias assessment with no language restrictions. The selection criteria included observational studies.

RESULTS

From the 953 studies recorded in databases, the authors included 18 studies. The meta-analysis results revealed that the most frequent position of impacted canines was 56.99% palatal (95% confidence interval [CI], 47.032% to 66.673%); the apical one-third was the most prevalent one-third for RR (56.87%; 95% CI, 38.880% to 73.628%). The intensity of RR was slight (43.2%; 95% CI, 35.229% to 51.352%), although 30.9% (95% CI, 19.007% to 44.261%) of RR was severe. Although the studies had different sample sizes, the main methodological problem was the absence of a control group and follow-up.

CONCLUSIONS

RR in maxillary incisors was correlated with their contact with maxillary canines during eruption. Delayed eruption or treatment of impacted canines may lead to resorption of the adjacent lateral and central incisors. All root levels and surfaces of teeth associated with impacted maxillary canines can be resorbed to different levels of severity, but the apical one-third with slight resorption is the most common.

PRACTICAL IMPLICATIONS

Knowing to what extent impacted canines are associated with root resorption of the adjacent tooth before starting any intervention, and being able to share this information with the patient, caregivers, or caregivers and patient, allows the choice of the most appropriate treatment.

Predictive factors for resorption of teeth adjacent to impacted maxillary canines

PURPOSE

The aim of this study was to assess the link between the degree of resorption of teeth adjacent to an impacted maxillary canine and the situation of the latter so as to identify factors predictive of resorption.

MATERIAL AND METHODS

This was a retrospective study concerning all patients with impacted maxillary canines who consulted the orthodontics department at the Center for dental care, teaching and research (CSERD) in Montpellier between 2010 and 2015, with a full radiological file including panorex, periapical long-cone and cone-beam images. In all, 25 patients with 31 impacted maxillary canines were analyzed. Measurements were made by a single operator using 2D images and 3D analysis; they concerned the quantitative and qualitative aspects of resorption of teeth adjacent to the impacted canines and also evaluation of the position of the maxillary canine and its follicular sac. The X² test was used to compare percentage resorption in men and women. Analysis of variance (ANOVA) was applied to compare the average degree of resorption of the adjacent teeth depending on the sagittal or vertical position of the impacted maxillary canine. Covariance analysis (ANCOVA) was used to study the average degree of resorption taking jointly into account the sagittal, vertical and transverse positions and adjusting for age and sex. Calculations were performed with a significance threshold of 5% using MyStat^® software.

RESULTS

Women made up 60.6% of the study population, with no significant age differences between the two sexes (21±5 years). The risk of adjacent resorption was not linked to age but was significantly greater (P-value=0.03) for women (60%) than for men (23%). The average degree of resorption is explained jointly by sagittal position (P-value=0.0001) and transverse position (P-value=0.01), after adjustment for age and sex. On the other hand, the average degree of resorption was not linked to vertical position, nor to the shape or size of the follicular sac.

CONCLUSION

This study leads to the conclusion that the risk of resorption of the lateral incisor is not linked to the buccal or palatal situation of the canine. The risk is greater when the canine is vertically above the lateral incisor root and close to the median palatine suture, suggesting a mechanical blockage by the apex of the lateral incisor.

Impacted maxillary canines and root resorption of adjacent teeth: A retrospective observational study

Background

The prevalence of impacted maxillary canine is reported to be between 1% and 3%. The lack of monitoring and the delay in the treatment of the impacted canine can cause different complications such as: displacement of adjacent teeth, loss of vitality of neighbouring teeth, shortening of the dental arch, follicular cysts, canine ankylosis, recurrent infections, recurrent pain, internal resorption of the canine and the adjacent teeth, external resorption of the canine and the adjacent teeth, combination of these factors. An appropriate diagnosis, accurate predictive analysis and early intervention are likely to prevent such undesirable effects. The objective is to evaluate, by means of a retrospective observational study, the possibility of carrying out a predictive analysis of root resorption adjacent to the impacted canines by means of orthopantomographs, so as to limit the prescription of additional 3D radiography.

Material and Methods

120 subjects with unilateral or bilateral maxillary impacted canine were examined and 50 patients with 69 impacted maxillary canine (22 male, 28 female; mean age: 11.7 years) satisfied the inclusion criteria of the study. These patients were subjected to a basic clinical and radiographic investigation (orthopantomographs and computerized tomography). All panoramic films were viewed under standardized conditions for the evaluation of two main variables: maxillary canine angulations (a, b, g angles) and the overlapping between the impacted teeth and the lateral incisor (Analysis of Lindauer). Binary logistic regression was used to estimate the likelihood of resorbed lateral incisors depending on sector location and angle measurements.

Results

Results indicated that b angle has the greatest influence on the prediction of root resorption (predictive value of b angle = 76%). If β angle <18° and Lindauer = I, the probability of resorption is 0.06.

Conclusions

Evaluation of b angle and superimposition lateral incisor/impacted canine analysed on orthopantomographs could be one of the evaluation criteria for prescribing second level examination (CT and CTCB) and for detecting root resorption of impacted maxillary canine adjacent teeth.

Key words:Impacted canine, root resorption, panoramic radiography, angulation, prediction.

Predictors of root resorption associated with maxillary canine impaction in panoramic images

OBJECTIVES

The aim was to identify a prediction model for root resorption (RR) caused by impacted canines based on radiographic variables assessed on 2D panoramic radiographs with the intention to reduce the need for additional cone beam computed tomography (CBCT) imaging.

MATERIALS AND METHODS

Three hundred and six patients (188 female, 118 male; mean age, 14.7 years; standard deviation, 5.6; range, 8.4-47.2 years) were included in the study. In total, 406 impacted maxillary canines were studied, from 206 patients with unilateral impaction and from 100 patients with bilateral impaction. Initial 2D panoramic radiography was available, and 3D CBCT imaging was obtained upon clinical indication. The generated radiographic variables and specific features investigated were collected on 2D panoramic imaging and were correlated to the presence/absence of RR detected on CBCT. A validation sample consisting of 55 canines from 45 patients with maxillary canine impactions was collected to validate the outcome of the present study.

RESULTS

The incidence of RR of the adjacent teeth was 33.8%. A prediction model using panoramic images for the possible presence of RR was established [area under the curve (AUC) = 0.74, 95% confidence interval (CI): 0.69-0.79] and validated by applying leave-one-out cross-validation (AUC = 0.71, 95% CI: 0.66-0.77). For the subgroup of presence of severe RR the discriminative ability increased to 0.80. In this prediction model, patient gender, canine apex, vertical canine crown position, and canine magnification were the strongest predictors for RR.

CONCLUSIONS

The final prediction model for RR based on available panoramic radiographs could be a helpful tool in justifying the need of additional CBCT examination.

Root resorptions related to ectopic and normal eruption of maxillary canine teeth - A 3D study

OBJECTIVE

To assess the incidence and severity of root resorption of maxillary incisors caused by ectopically and normally erupting maxillary canines and to analyse factors influencing root resorption of incisors using cone beam computed tomography.

SUBJECTS AND METHODS

The study sample comprised 59 patients with a total of 80 canines. Forty-six of the canines, in 37 patients, were defined as ectopic and 34 canines, in 22 patients, were defined as normal. The severity of root resorptions were analysed according to studies by Ericson and Kurol. Multiple logistics regression was used to evaluate the association between various factors and root resorptions.

RESULTS

The prevalence of root resorptions was significantly higher in the ectopic canine group, 11.0% of the central incisors and 67.6% of the lateral incisors in comparison to 0% and 36.2% in the normal erupting group. Most resorptions were defined as 'slight' and were located in the middle third of the root. There was a statistically significant relationship between canines located mesial to the midline of the lateral incisor and root resorption on the maxillary incisors.

CONCLUSION

The present results show that root resorption of maxillary lateral incisors was common in patients referred to CBCT imaging due to maxillary canine eruption disturbances. Although significantly more frequent in patients with ectopically erupting canines, lateral incisor resorption was also found in association with approximately every third of the normally erupting canines. The best predictor for root resorption seemed to be location of the canine mesial in relation to the midline of the lateral incisor root.

The effect of using CBCT in the diagnosis of canine impaction and its impact on the orthodontic treatment outcome

Aim:

To investigate the added-value of using CBCT in the orthodontic treatment method of maxillary impacted canines and treatment outcome.

Materials and Methods:

The sample consisted of 118 treated patients. The CBCT group (n = 58) (39 females/19 males with the mean age of 14.3 years) included those with conventional treatment records consisting of panoramic and cephalometric radiographs, intra-and extra-oral photographs, and dental casts and complemented with a CBCT scan for additional diagnostic information. The conventional group (n = 60) (31 females/29 males with mean age 13.1 years) included those with similar conventional treatment records but without CBCT imaging.

Results:

There were significant differences in the canine-related variables between both groups. The CBCT group had the higher level of difficulty and more severely displaced canines when compared with the conventional group. However, no significant difference was found between groups either in the number of treatment methods used or in the use of interceptive methods combined with other treatment modalities or choice of extraction versus non-extraction. In terms of treatment success and interval duration, no significant differences were found. However, treatment duration was significantly (4 months) shorter in the CBCT group compared with the conventional group (P = 0.023).

Conclusion:

CBCT has been used in cases with more severe symptoms of maxillary canine impaction. The use of CBCT improved the diagnostic capabilities and improved the chances of success in the more difficult cases to a level similar to that of simpler cases treated on the basis of 2D information.

Impacted maxillary canines and root resorptions of neighbouring teeth: a radiographic analysis using cone-beam computed tomography

The study analyses the location of impacted maxillary canines and factors influencing root resorptions of adjacent teeth using cone-beam computed tomography (CBCT). In addition, the interrater reliability between observers of two different dental specialties for radiographic parameters will be evaluated. CBCT images of patients who were referred for radiographic localization of impacted maxillary canines and/or suspicion of root resorptions of adjacent teeth were included. The study analysed the exact three-dimensional location of the impacted canines in the anterior maxilla, frequency and extent of root resorptions, and potential influencing factors. To assess interrater agreement, Cohen's correlation parameters were calculated. This study comprises 113 patients with CBCT scans, and 134 impacted canines were analysed retrospectively. In the patients evaluated, 69 impacted canines were located palatally (51.49 per cent), 41 labially (30.60 per cent), and 24 (17.91 per cent) in the middle of the alveolar process. Root resorptions were found in 34 lateral incisors (25.37 per cent), 7 central incisors (5.22 per cent), 6 first premolars (4.48 per cent), and 1 second premolar (0.75 per cent). There was a significant correlation between root resorptions on adjacent teeth and localization of the impacted canine in relation to the bone, as well as vertical localization of the canine. Interrater agreement showed values of 0.546-0.877. CBCT provides accurate information about location of the impacted canine and prevalence and degree of root resorption of neighbouring teeth with high interrater correlation. This information is of great importance for surgeons and orthodontists for accurate diagnostics and interdisciplinary treatment planning.