The relationship between vertical malocclusions and ossification changes in the cranial base and upper cervical spine

The growth and development of the maxillofacial complex share a common embryological origin with the cranial base and upper cervical spine; therefore, anomalies in these regions may be linked to variations in the skeletal pattern. This study aimed to evaluate the relationships between the morphological features of the sella turcica bridging, ponticulus posticus, posterior arch deficiency of the first cervical vertebra, known as the atlas, and the cervical vertebral maturation stages and vertical malocclusions. Randomly selected 300 pre-orthodontic treatment patients (aged 7 to 40 years) were divided into groups according to cervical stage (CS1-CS6) and type of vertical malocclusion. According to the study protocol, cephalometric analysis and evaluation of the sella turcica and atlas were performed twice by two researchers under the supervision of a radiologist. Statistical analysis was performed using SPSS 29.0. Sella turcica bridging was significantly more common in postpubertal patients (58.2%; p < 0.05). Ponticulus posticus and sella turcica bridging occurred more frequently in patients with low mandibular plane angle (43.3% and 51.1%, respectively), whereas atlas posterior arch deficiency occurred more frequently in patients with high mandibular plane angle (24.2%). However, only atlas posterior arch deficiency showed significant difference (p < 0.05). According to logistic regression, patients in the CS6 stage were less likely to have type 1 ponticulus posticus and more likely to have type 2 sella turcica bridging (p < 0.05). Patients with low angle were less likely to have atlas posterior arch deficiency (p < 0.05). Sella turcica bridging and atlas posterior arch deficiency are associated with the skeletal pattern and cervical stage. Sella turcica bridging was more prevalent during the postpubertal period, whereas atlas posterior arch deficiency was more prevalent in those with a high mandibular plane angle.

Cephalometric Assessment of Sella Turcica Morphology and Dimensions in Patients with Non-Syndromic Cleft Lip and Palate: A Systematic Review and Meta-Analysis

ObjectiveThis review aimed to analyze the size and morphology of the Sella Turcica (ST) in 2-dimensional cephalometric radiographs of individuals with non-syndromic cleft lip and or palate (CLP/CP) compared with non-cleft individuals.MethodsA comprehensive search of multiple electronic databases was conducted without language and date restrictions until October 12, 2024. Studies were included that assessed ST dimensions in lateral cephalograms and compared the patients with non-syndromic CLP or CP and non-cleft individuals. The studies' quality assessment was assessed using the JBI case-control guidelines and the Anatomical Quality Assurance checklist. Quantitative analysis was performed using the random-effects meta-analysis model. The GRADE approach was employed to evaluate the certainty of evidence.ResultsOut of 1087 studies, 10 met the inclusion criteria, and 6 were included in the quantitative analysis. Of all, 7 studies were rated moderate, 2 low, and 1 high quality. Unilateral CLP (UCLP) cohort showed statistically significant smaller dimensions for length (MD = -1.22; 95% CI: -2.21, -0.24), depth (MD = -0.65; 95% CI: -1.41, -0.11), and area (MD = -4.75; 95% CI: -7.22, -2.28) and the odds of ST bridging were more than twice compared to non-cleft control. No significant differences were observed in ST dimensions in bilateral CLP versus non-Cleft and UCLP.ConclusionThe evidence of differences in ST dimensions between non-cleft individuals and patients with UCLP is weak, owing to a greater risk of bias resulting from inadequate reporting of design variability, participant demographics, and measurement methods. Future studies with better methodology and larger sample sizes are needed.

Craniofacial and atlas vertebra structures in patients with maxillary palatally displaced canines: A cone-beam computed tomography-based retrospective study

INTRODUCTION

This retrospective cone-beam computed tomography (CBCT) study aimed to analyze the associations between maxillary palatally displaced canine (PDC) with the craniofacial and atlas vertebra structures.

METHODS

A total of 94 patients (47 with PDC and 47 normal) were included. Then, their CBCT data were reconstructed and analyzed to measure the 3-dimensional angular positions of canines, the structures of sella turcica, atlas vertebra, and cranial base. Comparisons of continuous variables between 2 groups were performed using the independent samples t test or the Mann-Whitney U test, whereas 1-way analysis of variance or Kruskal-Wallis tests were used for comparisons among multiple groups. Categorical variables were compared using the chi-square test or Fisher exact test, as appropriate. Binary logistic regression analyses, along with Spearman or Pearson correlation analyses, were conducted to determine the associations between variables.

RESULTS

No significant differences were observed in sella turcica structures or the occurrence of ponticulus posticus between the 2 groups (P >0.05). The anterior cranial base length was significantly smaller, and the cranial base angle was significantly larger in subjects with PDC (P <0.05). Moreover, a significant negative correlation was identified between anterior cranial base length and the occurrence of PDC (P <0.05). However, the angular positions of canines showed no significant correlation with any craniofacial variables.

CONCLUSIONS

On the basis of CBCT data, the structures of sella turcica and atlas vertebra did not differ between patients with PDC and those with normally erupted canines. However, patients with PDC exhibited a significantly shorter anterior cranial base length and a greater cranial base angle, suggesting a possible developmental link between cranial base morphology and maxillary canines. The explicit relationship and clinical significance of PDC with craniofacial structures require further investigation.

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.

The Relationship Between Orthodontic Malocclusion and Morphological Features of Sella Turcica Bridging and Ponticulus Posticus

Background and Objectives: Recent years have been marked by a search for new relationships between malocclusions and the morphological features of the cranial base and upper cervical spine. The aim of this study was to evaluate the relationship between skeletal orthodontic malocclusions and the morphological features of sella turcica bridging (STB) and ponticulus posticus (PP). Materials and Methods: The study sample consisted of 300 randomly selected pre-orthodontic treatment patients aged 7-40 years. Cephalometric analysis was performed twice by two researchers. The patients were divided into three groups according to the type of skeletal malocclusion. Statistical analysis was performed using SPSS 29.0 software. Results: The prevalence of incomplete PP was 40%, and the prevalence of complete PP was 11.33% and was significantly more common in males (56.7%). STB had a prevalence of 52.67% (15.67% complete, 37.0% partial), with a significantly higher prevalence in females (60.1%, p < 0.001). PP and STB were more common in Class II patients, followed by Class I and Class III. However, only PP showed a statistically significant difference (p = 0.042). According to logistic regression, men were twice as likely to have an open groove of PP (p = 0.015), while females had higher odds of partial and complete STB (p < 0.05). Class II malocclusion increases the odds of type 2 and type 4 PP as well as partial STB. However, it was not statistically significant (p > 0.05). Conclusions: The morphological features of sella turcica bridging and ponticulus posticus were related to sex and the orthodontic skeletal pattern. Ponticulus posticus was more prevalent in males, while sella turcica bridging was more prevalent in females; both conditions were more common in patients with a Class II skeletal pattern. Males were more likely to have an open groove of ponticulus posticus, whereas females were twice as likely to have both forms of sella turcica bridging.

How successful is the CatBoost classifier in diagnosing different dental anomalies in patients via sella turcica and vertebral morphologic alteration?

BACKGROUND

To investigate how successfully the classification of patients with and without dental anomalies was achieved through four experiments involving different dental anomalies.

METHODS

Lateral cephalometric radiographs (LCRs) from 526 individuals aged between 14 and 22 years were included. Four experiments involving different dental anomalies were created. Experiment 1 included the total dental anomaly group and control group (CG). Experiment 2 only had dental agenesis and a CG. Experiment 3 consisted of only palatally impacted canines and the CG. Experiment 4 comprised patients with various dental defects (transposition, hypodontia, agenesis-palatally affected canine, peg-shaped laterally, hyperdontia) and the CG. Twelve sella measurements and assessments of the ponticulus posticus and posterior arch deficiency were given as input. The target was to distinguish between anomalies and controls. The CatBoost algorithm was applied to classify patients with and without dental anomalies.

RESULTS

In order from lowest to highest, the predictive accuracies of the experiments were as follows: experiment 4 < experiment 2 < experiment 3 < experiment 1. The sella area (SA) (mm2) was the most important variable in experiment 1. The most significant variable in prediction model of experiment 2 was sella height posterior (SHP) (mm). Sella area (SA) (mm2) was again the most relevant variable in experiment 3. The most important variable in experiment 4 was sella height median (SHM) (mm).

CONCLUSIONS

Every prediction model from the four experiments prioritized different variables. These findings may suggest that related research should focus on specific traits from a diagnostic perspective.

Associations across 22 dental and craniovertebral anomalies or variations, sagittal skeletal relationships, and vertical growth patterns: a comprehensive epidemiological study of 43 dentoskeletal traits

INTRODUCTION

Despite researchers' recent interest in identifying links between some dental and craniovertebral abnormalities, there are many important, unassessed gaps in our knowledge of this matter. In addition, previous samples were small. This large study aimed to examine, for the first time, the occurrence/severity of numerous dental and skeletal anomalies or variations and their correlations with each other and with growth patterns.

METHODS

This epidemiological study was conducted on pretreatment radiographs of 1194 patients from 3 cities (815 females). Skeletal sagittal skeletal relationships and vertical growth patterns were determined. The occurrence/severity were assessed for: cervical vertebral fusion (CVF), atlas posterior arch deficiency (APAD), ponticulus posticus (PP), sella turcica bridging (STB), hypodontia, oligodontia, hyperdontia, missing of maxillary laterals, microdontia, macrodontia, root dilaceration, odontoma, taurodontism, dental fusion, dental gemination, enamel pearl, permanent molar ankylosis, primary molar ankylosis, dens in dente, dens invaginatus, dental impaction, ectopic eruption, and dental transposition. Incidental findings were recorded as well. Concurrent anomalies, sex dimorphism, and correlations across variables were examined statistically, adjusting for the false discovery rate (α = 0.05).

RESULTS

Prevalence was calculated for 43 dentoskeletal traits/anomalies (22 abnormalities/variations [plus their severities/types] as well as 21 incidentally found traits/anomalies). Dental impaction may be more common in hyperdivergent and severer cases of sella bridging; also, primary molar ankylosis was associated with missing teeth. Dental impaction was associated only with STB and not with PP, APAD, or vertebral fusion. The only association observed among the four skeletal anomalies was seen between APAD and CVF. Merely the variables 'sagittal skeletal relationships, vertical growth patterns, PP, and APAD' showed sexual dimorphism; of these, only vertical growth pattern and APAD remained sexually dimorphic after adjusting for the FDR; still, the other two remained marginally significant and worth further evaluations. Sex dimorphism did not exist in concurrent abnormalities. The skeletal Class III was associated with the concurrent occurrence of craniovertebral, dental, and dentoskeletal abnormalities. Skeletal Class I was associated with fewer occurrences of concurrent dental anomalies. Vertical growth patterns were not associated with concurrent dental or dentoskeletal anomalies. However, the hyperdivergent pattern was associated with fewer cases of concurrent craniovertebral abnormalities.

CONCLUSIONS

STB and hyperdivergent pattern were associated with dental impaction. However, APAD, CVF, or PP were not associated with dental impaction. APAD was associated with CVF. Sexual dimorphism existed conclusively in the case of vertical growth patterns and APAD. Concurrent abnormalities (dental, skeletal, and dentoskeletal) were associated with skeletal Class III.

Association between sella turcica bridging and the impaction severity of palatally displaced canines: A retrospective study

INTRODUCTION

This retrospective study aimed to investigate the association between the extent of the bridging and dimensions of sella turcica and the impaction severity of palatally displaced canines. Secondarily, any possible association between skeletal age and gender was evaluated.

METHODS

Panoramic and cephalometric radiographs of 94 patients (63 female, 31 male; 19 pre-peak, 75 post-peak) with palatally displaced canines were evaluated. Sector classification and α angle were used to determine the impaction severity of palatally displaced canines on panoramic radiographs. The distance from the cusp tip of the palatally displaced canines to the occlusal plane (d) and the extent of the bridging and dimensions of the sella turcica were evaluated on cephalometric radiographs.

RESULTS

Sella turcica bridging and dimensions did not vary regarding the impaction severity of palatally displaced canines, but a significant association was found between sella turcica bridging and skeletal age (P = 0.038). Class II (33.3%) and Class III (12.0%) bridging was higher in postpubertal patients. No differences between females and males were detected for the extent of bridging and dimensions of the sella turcica.

CONCLUSIONS

These findings indicate no association between sella turcica bridging and dimensions and the impaction severity of palatally displaced canines. Sella turcica bridging is more frequent in the postpubertal period, whereas gender does not influence sella turcica bridging. More studies are needed to evaluate if the extent of sella turcica bridging may be indicative of severely impacted palatal canines, which in turn would allow for careful monitoring of patients from an early age and for the clinician to take preventive measures.

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.

Predictive Analysis of Maxillary Canine Impaction through Sella Turcica Bridging, Ponticulus Posticus Calcification, and Lateral Incisor Anomalies: A Retrospective Observational Study

Maxillary canine impaction is an increasing dental anomaly and is often related to other dento-skeletal anomalies. The aim of this work is to support the clinician in evaluating the relationship between a displaced maxillary canine and clinical (the features of lateral incisors)/skeletal (ponticulus posticus and sella turcica bridging) anomalies through orthopanoramic radiographs, lateral cephalograms, and plaster casts to identify the parameters that best predict maxillary canine impaction. A retrospective observational study was carried out on the analysis of the medical records, radiographic findings (panoramic radiographs and lateral cephalograms), and plaster casts of 203 orthodontic patients divided into a case group, with at least one impacted maxillary canine, and a control group, without an impaction. A chi-square test and logistic regression analysis were used to analyze the data. A statistically significant association was found between the impaction of the maxillary canine and the female sex, the bridging of the sella turcica, the ponticulus posticus calcification, and the anomaly of the lateral incisor; a logistic regression revealed that these significant variables were found to be positive predictors of impacted maxillary canines, particularly in reference to the impaction in the palatal area. Finding one of these clinical and radiographic elements can represent a predictive sign of the possible impaction of the maxillary canine.

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.

Convolutional Neural Network Performance for Sella Turcica Segmentation and Classification Using CBCT Images

The present study aims to validate the diagnostic performance and evaluate the reliability of an artificial intelligence system based on the convolutional neural network method for the morphological classification of sella turcica in CBCT (cone-beam computed tomography) images. In this retrospective study, sella segmentation and classification models (CranioCatch, Eskisehir, Türkiye) were applied to sagittal slices of CBCT images, using PyTorch supported by U-Net and TensorFlow 1, and we implemented the GoogleNet Inception V3 algorithm. The AI models achieved successful results for sella turcica segmentation of CBCT images based on the deep learning models. The sensitivity, precision, and F-measure values were 1.0, 1.0, and 1.0, respectively, for segmentation of sella turcica in sagittal slices of CBCT images. The sensitivity, precision, accuracy, and F1-score were 1.0, 0.95, 0.98, and 0.84, respectively, for sella-turcica-flattened classification; 0.95, 0.83, 0.92, and 0.88, respectively, for sella-turcica-oval classification; 0.75, 0.94, 0.90, and 0.83, respectively, for sella-turcica-round classification. It is predicted that detecting anatomical landmarks with orthodontic importance, such as the sella point, with artificial intelligence algorithms will save time for orthodontists and facilitate diagnosis.

Relationship between Craniovertebral Abnormalities and Maxillary Lateral Incisors Agenesis: A Case-Control Study

Objectives

This study aimed to investigate whether the sella turcica bridging (STB) and ponticulus posticous (PP) are associated with the congenital missing maxillary lateral incisor (CMMLI), based on lateral cephalograms of patients who needed orthodontic treatment.

Materials and Methods

This case-control study examined 160 panoramic images and lateral cephalograms of 2000 patients seeking orthodontic treatment. The case group included 80 patients with CMMLI (40 with unilateral and 40 with bilateral CMMLI) and the control group included 80 patients without CMMLI. Panoramic images were used to diagnose CMMLI and lateral cephalograms showed STB and PP extension. The researchers used statistical analyses to examine the relationship among STB, PP, and CMMLI (P < 0.05).

Results

The prevalence of STB type I, II, and III was 47.5%, 35%, and 17.5% in the case group and 72.5%, 22.5%, and 5% in the control group, respectively, determining a positive relationship between CMMLI and STB and a significant relationship between bilateral CMMLI and STB (P < 0.05 for both). The prevalence of normal, incomplete, and complete PP extension was 80%, 5%, and 15% in the case group and 82.5%, 5%, and 12.5% in the control group, respectively. There was no significant relationship between CMMLI and PP extension (P > 0.05) and between the STB and the PP extension (P > 0.05).

Conclusion

CMMLI was significantly related to STB but not to PP extension. Investigating the relationship between unilateral/bilateral CMMLI, STB, and PP has shown only a significant relationship between bilateral CMMLI and STB. There was no significant relationship between STB and PP extension.

Calcification of the Atlanto-Occipital Ligament (Ponticulus Posticus) in Orthodontic Patients: A Retrospective Study

Background: Ponticlus Posticus (PP) is a rare anomaly of the first cervical vertebra easily identifiable in lateral cephalometric radiograph and typically required for orthodontic diagnosis. The aim of this study is to evaluate the PP prevalence in lateral Cephalograms in a cohort of orthodontic patients treated at the Dental School of the University of Bari ‘Aldo Moro’, Italy, and to find possible connection between PP and other dental anomalies, as well as the patient’s cephalometric characteristics. Methods: A total of 150 panoramic radiographs and 150 lateral Cephalograms, obtained for orthodontic use only, were evaluated. No patients were referred to for congenital syndromes or disease, or a history of previously occurred maxillofacial trauma. A detailed cephalometric study was performed for each patient, and the whole cohort was divided according to the common three dental malocclusion classes. The values obtained were analyzed using the Chi-Square Test. Results: PP prevalence was 8% (12 of 150 cases), where the complete and partial forms observed 4.7% and 3.3%, respectively. Although females were more affected (9.6%), no statistically significant sex-related difference was found. Furthermore, no statistically significant relationship regarding age or dental anomalies (dental agenesis/palatal impacted canines) among the groups was observed either. Cephalometric analyses revealed that half of the subjects with PP were sagittal skeletal class I and had vertical hyper-divergence. Conclusions: PP is a frequent anatomical variation of the cervical vertebra, apparently unrelated to the skeletal malocclusion type or dental anomalies. The current study needs to further confirm the congenital hypothesis of PP’s origin already reported in literature.

Research Progress of Ponticulus Posticus: A Narrative Literature Review

Study Design

Narrative review.

Objective

The purpose of this review was to consolidate the current literature related to ponticulus posticus (PP) and to improve the systematic understanding of this anatomical variant of atlas among spine surgeons.

Methods

Articles reviewed were searched in PubMed, Ovid MEDLINE, and Embase. All articles of any study design discussing on PP were considered for inclusion. Two independent authors read article titles and abstracts and included appropriate articles. The relevant articles were studied in full text.

Results

A total of 113 literatures were reviewed and consolidated in this narrative review. These articles are roughly divided into the following five subcategories: (1) epidemiology, (2) pathology and anatomy, (3) clinical presentation, (4) surgical significance, and (5) radiographic examination.

Conclusion

The PP is non-negligible with a high prevalence. The PP compresses the V3 segment of the artery, the suboccipital nerve, and the venous plexus, consequently contributing to the incidence of neurological pathologies. When a PP is observed or suspected on a lateral radiograph, we recommend that a computed tomography (CT) scan of a patient who is about to receive a C1 lateral mass screw (C1LMS) should be performed, which could determine a safe entry point and the right trajectory of screw insertion.

Evaluation of Dimension and Bridging of Sella Turcica and Presence of Ponticulus Posticus in Individuals With and Without Cleft: A Comparative Study

OBJECTIVE

Sella turcica abnormalities such as sella turcica bridging (STB) have been observed frequently among patients with craniofacial anomalies. Ponticulus posticus (PP) is an important structure and its presence causes complications during surgeries. Due to the importance of these structures, this study aimed to evaluate the prevalence of STB, PP, and dimensions of the sella turcica in individuals with and without cleft.

DESIGN

A cross-sectional study.

SETTING

Orthodontic and Radiology Departments in a public dental school, Tehran, Iran.

PATIENTS

Eighty-three lateral cephalograms of individuals with cleft and ninety-two cephalograms of class I individuals without cleft.

MAIN OUTCOME MEASURES

Length, depth, and maximum anterior-posterior diameter (APD) of sella turcica, presence of STB (classified as types 1, 2, and 3), and PP.

RESULTS

In the group with cleft, 19.3% of individuals had type I, 65.1%, type II, and 15.7%, type III STB. In the group without cleft, 15.2% had type I, 73.9%, type II, and 10.9%, type III STB. In the group with cleft, 65.1% of individuals had no PP, 24.1%, incomplete, and 10.8%, complete PP while in the group without cleft, 56.5% had no PP, 29 31.5%, incomplete, and 12%, complete PP.

CONCLUSION

The sella turcica dimensions, STB, and PP prevalence were not significantly different between individuals with and without cleft. The sella turcica length and prevalence of STB and PP were not affected by age, sex, and cleft type. However, the depth and the APD were affected by age.

Sella turcica bridging: a systematic review

PURPOSE

Sella turcica bridging (STB) has significant implications during neurosurgery, since it alters regional anatomy; however, no studies have investigated the global prevalence of STB. Our systematic review aimed to establish the global prevalence of STB, in specimens/individuals with and without comorbidities, in males and females, and of partial, complete, unilateral, and bilateral bridging.

METHODS

A literature search was conducted in MEDLINE/PubMed, ScienceDirect, and Google Scholar with various key words relating to Sella turcica bridging. Quantitative data were extracted and statistically analysed.

RESULTS

Eighty-two studies satisfied our inclusion criteria. The mean prevalence of STB was 26.54%, and most prevalent in Europe. STB was detected more frequently using radiological investigations. STB was less prevalent in healthy individuals (21.12%) when compared to individuals with comorbidities (33.31%). Partial STB was found to be the more prevalent in both individuals with (41.06%) and without (21.55%) comorbidities. The prevalence of unilateral and bilateral STB was only studied in healthy individuals, with unilateral bridging being the more prevalent (6.26% vs 3.84%).

CONCLUSION

The global overall prevalence of Sella turcica bridging in the general population was found to be higher than previously thought. Anatomical and embryological textbooks should consider including information on STB in their texts, due to its considerable prevalence and effects to the regional anatomy.

Evaluation of mandibular indices and cephalometric parameters in adolescents with impacted maxillary canines

Objectives:

Maxillary impacted canines have an important place in orthodontics for the reason of being a common anomaly and its treatment is time consuming and difficult. The aim of this study was to investigate the mandibular indexes and cephalometric parameters in adolescents with impacted maxillary canines.

Materials and Methods:

The radiographs of 4026 patients aged 12–19 years old were scanned and a total of 155 patients were included in the study. Subjects were divided into three groups according to the permanent maxillary canines: Bilateral impacted canine (BIC) (52 subjects; mean age 15.02 ± 1.74 years), unilaterally impacted canine (UIC) (51 subjects; mean age 14.89 ± 1.39 years), and the control (52 subjects; mean age 14.84 ± 1.65 years) groups. Skeletal, soft tissue and dental measurements were performed on cephalometric radiographs. Mandibular index analyzes including the panoramic mandibular index (PMI), mental index (MI), antegonial index (AI), and gonial index (GI) measurements and also angular measurements of impacted maxillary canines were performed on panoramic radiographs. Data were analyzed statistically and P < 0.05 was considered significant.

Results:

Maxillary skeletal and dental measurements showed retrusive positioned maxillary dental arch in the sagittal direction in the impacted canine groups (P < 0.05). PMI and MI values were greater in the BIC and UIC groups than in control group (P < 0.05). There was no statistically significant difference in AI value among groups (P < 0.05). GI value of BIC group was found statistically lower than other groups (P < 0.05).

Conclusion:

Individuals with impacted maxillary canines have more retrusive maxillary dental arch and soft-tissue components. Furthermore, mandibular cortex was thicker in subjects with impacted maxillary canine than individuals with not and clinicians should keep in mind this when examine the panoramic radiographs in terms of early diagnosis of impacted maxillary canine teeth.

Correlation of ponticulus posticus with dentofacial skeletal patterns

Background:

Methods:

Results:

Conclusions:

A correlative study of sella turcica bridging and dental anomalies related to size, shape, structure, number and eruption of teeth

OBJECTIVE:

The main objective of this study is to get a wider and clearer idea about the relationship between sella turcica bridging and the type of dental anomalies related to size, shape, number, structure and eruption of teeth.

MATERIALS AND METHODS:

For the present study, 50 pretreatment lateral cephalometric radiographs showing complete sella turcica bridging were retrieved from the 500 existing case records of patients. The control group consisted of 50 pretreatment lateral cephalograms without sella turcica bridging retrieved from the same case records by using simple random sampling. After collection of the samples, retrospective study was performed with the analysis of patient records to assess any associated dental anomaly in patients with sella turcica bridging and patients without sella turcica bridging. Shafer's classification of morphological variations in size, shape, structure, number and eruption of teeth was used to analyze and group the dental anomalies.

RESULTS:

The incidence of dental anomalies related to number and size of teeth was found to be higher in cases with sella turcica bridging.

CONCLUSION:

Lateral cephalogram is used by orthodontist routinely for diagnosis and treatment planning; it can be used as a prediction tool for dental anomalies as well. Early detection of skeletal anomalies can be used to forecast the presence of dental anomalies later in life, which will help the clinician to adopt preventive measures.

Assessments of Prevalence of Ponticulus Posticus, Atlas Posterior Arch Deficiency, Sella Turcica Bridging, Maxillary Canine Impaction, and Associations Among Them in 500 CBCTs of Italian Orthodontic Patients

Background: The ponticulus posticus (PP) is an important anomaly of the atlas (C1 vertebra) with a complete or partial bone bridge that transforms the groove of the vertebral artery (VA) into a canal (arcuate foramen). The aim was to retrospectively determine prevalence of PP evaluating morphological features and the possible association with other dentoskeletal anomalies in the midface and neck area such as maxillary canine impaction (MCI), atlas posterior arch deficiency (APAD), and sella turcica bridging (SB).

Methods: This study was conducted in the Department of Medical, Oral and Biotechnological Sciences of the University “G. D'Annunzio” in Chieti. The detection of PP was performed on 500 patients with cone beam CT (CBCT) images (6 to 87 years).

Results: Analysis revealed the presence of uni- and bi-lateral PP in 110 patients (22%): 24 (4.8%) patients with bilateral complete PP, 12 (2.4%) patients with complete PP on the left, 6 (1.2%) patients with complete PP on the right, 8 (1.6%) patients with complete PP on the right and partial PP on the left, 6 (1.2%) patients with complete PP on the left and partial PP on the right, 26 (5.2%) patients with partial bilateral PP, 18 (3.6%) patients with partial left PP, and 10 (2%) patients with partial PP on the right. The Chi-squared statistic confirmed that there are significant associations between MCI and PP (p = 0.020) and between SB and MCI (p &lt;0.00001). No correlation between chronological age and presence of the PP (p = 0.982), between chronological age and morphotypes of the PP (p = 0.779), between APAD and the PP (p = 0.0757), between SB and the PP (p = 0.111), and between APAD and MCI (p = 0.222) were found.

Conclusion: This observational study showed how bilateral partial variant and bilateral complete variant are the most represented morphotypes in all the age groups. The prevalence of MCI is positively associated with PP and with SB.

Sella turcica bridging and ponticulus posticus calcification in subjects with different dental anomalies

INTRODUCTION

This study aimed to evaluate and compare the bridging and dimensions of the sella turcica and calcification of the ponticulus posticus in subjects with different dental anomalies.

METHODS

Pretreatment records of orthodontic patients with palatally impacted canines (n = 95), mandibular second premolar agenesis (n = 45), maxillary lateral incisor agenesis (n = 75), tooth transpositions (TT, n = 25), peg-shaped maxillary lateral incisors (n = 30), and third molar agenesis (TMA, n = 145) were analyzed and compared with the control group (CG) consisting of 145 subjects with skeletal Class I malocclusion and no dental anomalies. The length, diameter, and depth of the sella turcica were calculated for each patient. The degree of sella turcica bridging was scored as type I, II, and III, whereas the extent of ponticulus posticus was classified as Class I, II, and III.

RESULTS

Only decreases in the length and diameter of the sella turcica in subjects with TT were found to be statistically significant. Although type II bridging frequency was found to be significantly lower in subjects with mandibular second premolar agenesis, maxillary lateral incisor agenesis, TT, and TMA, type III bridging frequency was found to be significantly higher only in subjects with TMA. The decrease in Class I calcification frequencies and the increase in Class II calcification frequencies were found to be significant in subjects with palatally impacted canines, TT, and TMA compared with the CG. In addition, the presence of Class III calcification was found to be significantly more frequent in subjects with TMA than in the CG.

CONCLUSIONS

Although type II and type III bridging frequencies were found to be higher than in previous studies because of the higher type II bridging frequency in the CG, type II bridging frequency was found to be insignificant. Furthermore, an increased frequency of ponticulus posticus calcification was observed in subjects with palatally impacted canines, TT, and TMA.

Sella Turcica Bridging and Tooth Agenesis in Children With Unilateral Cleft Lip and Palate

AIM

To investigate differences in sella turcica size and bridging in children with unilateral cleft lip and palate (UCLP) with or without concomitant dental anomalies.

PATIENTS AND METHODS

A cross-sectional study was carried out looking at 56 children with nonsyndromic UCLP. Lateral cephalograms, taken before alveolar bone grafting, were used to assess sella turcica height, width, area, and bridging. Panoramic radiographs were used to evaluate the presence of dental anomalies in the cleft area including agenesis, supernumerary, and peg-shaped lateral incisors. Differences between sella turcica measurements in the presence or absence of dental anomalies were assessed using t tests. Differences between the prevalence of dental anomalies and sella turcica bridging were assessed using χ² and Fisher exact tests. Multinomial logistic regression was used to investigate potential associations between sella measurements and dental anomalies.

RESULTS

Twenty-six of the 56 children presented with agenesis of the cleft-side lateral incisor, while 7 had a supernumerary, and 19 had a peg-shaped lateral incisor. With regard to sella turcica bridging, 27 children had no calcification, 25 partial and 4 complete calcification. Children with agenesis of the cleft-side lateral incisor showed a shorter sella maximum height (P = .010) and a smaller area (P = .019). When looking at sella turcica bridging, 100% of children with complete calcification showed agenesis of the cleft-side lateral incisor, compared with 52% and 33% of children with partial calcification and no calcification, respectively (P = .034).

CONCLUSIONS

Children with UCLP and sella turcica bridging are more likely to present with agenesis of the cleft-side maxillary lateral incisor.

Comparison of cervical vertebral anomalies and sella turcica bridging in different growth stages with various vertical skeletal growth patterns

PURPOSE

To compare cervical vertebral anomalies and sella turcica bridging (STB) in different growth stages in orthodontic patients with different vertical skeletal growth patterns.

METHODS

Lateral cephalometric radiographs (LCR) of 270 patients in the preadolescent, adolescent, or postadolescent periods and having low angle [LA], normal angle [NA], or high-angle [HA] vertical skeletal growth patterns were evaluated retrospectively. STB was visualized using LCRs while evaluating the deficiency of ponticulus posticus (PP) and atlas posterior arch (PAA) associated with the atlas bone. The Pearson chi-square and Fisher's exact tests were used for categorical data and one-way ANOVA for numerical data.

RESULTS

The prevalence of fully calcified PP and STB increased from the preadolescent (PP, 10.0%; STB, 11.1%) to the postadolescent period (PP, 24.4; STB, 21.1%); they did not differ from vertical skeletal growth patterns (p > 0.05). The prevalence of PAA deficiency is significantly higher in individuals with LA (46.7%) than with other angles (NA, 27.8%; HA, 26.7%). The vertical skeletal growth pattern was significantly related to STB in the preadolescent period and PAA in the postadolescent period.

CONCLUSIONS

Different anomalies during different growth periods correlate with the vertical skeletal growth pattern. It will be useful to evaluate a different anomaly according to the relevant growth period.

Association of maxillary dental developmental abnormality with precocious puberty: a case-control study

Background

Dental studies of precocious puberty have focused on examination of jaw and dentition growth. The aim of the study was to analyze the relationship between precocious puberty and maxillary dental developmental abnormalities (DDAs).

Methods

This retrospective study was conducted on the Korean patients in whom dental panoramic and hand-wrist radiographs had been taken before they were 15 years of age. The maxillary DDAs were assessed as mesiodens, congenital missing teeth, peg-shape lateral incisors, or impacted teeth. The chronological ages of the control group members were within the normal range of the hand-wrist bone age. Others with a peak luteinizing hormone of ≥ 5 and < 5 IU/L were allocated to central precocious puberty (CPP) and peripheral precocious puberty (PPP), respectively.

Results

Of the enrolled 270 patients, 195, 52, and 23 were allocated to the control, CPP, and PPP groups, respectively. The maxillary DDAs were significantly more prevalent in the CPP group than in the other groups. Among those with maxillary DDA, the mesiodens predominated. Age- and sex-adjusted multivariate analysis revealed maxillary DDA (odds ratio, 3.36; 95% CI, 1.60-7.05) and especially mesiodens (odds ratio, 5.52; CI, 2.29-13.28) to be significantly associated with CPP.

Conclusions

Maxillary DDAs were significantly more prevalent in the CPP group than in the PPP or control groups. Among the many types of maxillary DDAs, mesiodens was significantly associated with CPP and may be considered a predictor of the development of CPP.

Associations among palatal impaction of canine, sella turcica bridging, and ponticulus posticus (atlas arcuate foramen)

INTRODUCTION

The palatal impaction of canine (PIC) can be predicted by some head and neck skeletal anomalies or variants. Since studies on this regard (especially vertebral anomalies) are scarce, this study was conducted.

METHODS

This case-control study was done on 46 PIC orthodontic patients (34 females, 12 males) and 46 control orthodontic patients (36 females, 10 males). The diagnosis of PIC was done on lateral cephalographs and panoramic radiographs. On cephalographs, sella turcica bridging (occurrence and severity) and ponticulus posticus (occurrence and severity) were assessed. Associations between PIC, sella bridging, and ponticulus posticus were examined statistically (α = 0.05, β ≤ 0.2).

RESULTS

Cases' and controls' mean ages were 17.7 ± 4.0 and 17.4 ± 3.5, respectively. Of the case subjects, 22, 22, and 2 had respectively types I (normal), II, and III of sella bridging, while these numbers were 34, 12, and 0 in controls (chi-square P = 0.023 for severity, 0.010 for occurrence). Ponticulus posticus was observed in 28 cases (7 completed) and 17 controls (6 completed, P = 0.022 for occurrence, 0.056 for severity). Sella bridging was not associated with ponticulus posticus (Spearman P = 0.150). According to binary logistic regression, sella bridging can increase the odds of palatal canine impaction for OR = 2.8 times, while ponticulus posticus for OR = 2.6. Age and sex did not affect sella bridging or ponticulus posticus.

CONCLUSIONS

Both sella bridging and ponticulus posticus can predict an increased rate of PIC for more than 2.5 times.

Association between Anatomical Variations and Maxillary Canine Impaction: A Retrospective Study in Orthodontics

This study aims to evaluate whether or not there is a higher prevalence of skeletal abnormalities in subjects with maxillary canine impaction (MCI). This retrospective study was performed on 67 subjects with maxillary canine impaction (test group) and on 67 patients without dental displacement (control group). Sella turcica bridging (SB), ponticulus posticus (PP), atlas posterior arch deficiency (APAD) and the morphology of sella turcica and pterygopalatine fissure were evaluated on lateral cephalometric radiographs. Statistical analysis was performed using chi-square, Mann–Whitney test and multivariate logistic models; the level of significance was p < 0.05. Results showed that in the test and control groups 87% and 62.7% of patients had SB, respectively. PP was observed in 60% of patients in the test group and in 16.4% of patients in the control group. APAD was observed in 9% of test group and in 4.5% of the control group. Skeletal anomalies were significantly increased (p < 0.05) in subjects with MCI. A significant difference between the groups was observed in regards to the shape of the pterygopalatine fissure, found to be less wide and longer in the test group. SB, PP and APAD were higher in subjects with MCI; furthermore, an elongated pterygopalatine fissure was significantly associated with MCI.

Cervicovertebral anomalies and/or normal variants in patients with congenitally bilateral absent maxillary lateral incisors

OBJECTIVE

To determine whether there is a relationship between congenitally bilaterally absent maxillary lateral incisors (BAMLIs) and skeletal anomalies and/or normal variants.

MATERIALS AND METHODS

The records of 86 patients (62 girls, 24 boys; age 12-17 years) with congenitally BAMLIs and 86 patients (55 girls, 34 boys; age 13-18 years) without any dental or skeletal anomalies were collected and evaluated retrospectively. The study was based on the evaluation of lateral cephalometric and orthopantomographic radiographs. Posterior arch deficiency of the atlas bone (PADA); atlanto-occipital ligament calcification, known as "ponticulus posticus" (PP); and interclinoid ligament calcification, known as "sella turcica bridging" were recorded for each participant. Pearson χ2 and Fisher exact tests were used to evaluate and compare skeletal anomalies and/or normal variants between patients with BAMLIs and the control group.

RESULTS

The prevalence of cervicovertebral anomalies and/or normal variants seen in the lateral cephalometric radiographs was higher in patients with BAMLI than in the control group. The prevalence of PP was lower and that of PADA was higher in patients with BAMLIs than in the control group (P < .05).

CONCLUSION

The prevalence of PADA was increased and that of PP formation was decreased in patients with BAMLIs. There was a significant relationship between skeletal anomalies and/or normal variants.

Evaluation of the relationship between impacted canines and three-dimensional sella morphology

PURPOSE

The purpose of this study was to assess the three-dimensional morphometric features of the sella turcica using cone beam computed tomography (CBCT) in subjects with unilateral and bilateral maxillary impacted canines and normal controls.

METHODS

In this retrospective study, CBCT images captured with ultra-low dose protocol of 73 subjects (21 males, 52 females; mean age 20.01 ± 6.53 years) with unilateral or bilateral maxillary impacted canines (29 unilateral and 29 bilateral) and 15 controls were evaluated. Nineteen different measurements of the pituitary fossa were made on CBCT images. To evaluate the normality, the Kolmogorov-Smirnov test was used. The nonparametric statistical Kruskal-Wallis and Mann-Whitney U tests were applied to analyze the significant differences among and between the groups. Statistical significance was set at 5%.

RESULTS

No measurement differed significantly among the groups (all p > 0.05) other than the right sella length, which differed between the unilateral and bilateral test groups and the unilateral test group and controls (both p < 0.05). The bilateral test group and control group did not differ significantly, but both exhibited greater right sella length than did the unilateral test group (p > 0.05).

CONCLUSIONS

Other than the right sella length, there were no among-group differences in the mean pituitary fossa measurements of subjects with impacted unilateral and bilateral canines and normally erupted canines. The right sella length was lower in subjects with impacted unilateral canines than in those with bilateral impacted canines and normal controls.

Morphology of palatally displaced canines and adjacent teeth, a 3-D evaluation from cone-beam computed tomographic images

Background

The goal of this study was to investigate in patients with unilateral palatally displaced canine (PDC) the morphology of maxillary teeth from cone-beam computed tomography (CBCT) scans both on the PDC side and non-PDC side using a “surface matching” technique.

Methods

CBCT images from 28 patients (mean age 16.04 ± 1.77 years) with unilateral PDC were selected. Each tooth in this study was segmented and then rendered into a 3D model using Mimics Research software and the root length was measured. Afterwards, 3D deviation analysis between the PDC and non-PDC side was carried out using Geomagic Control X software.

Results

Statistically significant differences (p ≤ 0.001) were obtained when comparing the root lengths and volumes of lateral incisors from the PDC side, non-PDC side and control group. In accordance with the findings of 3D deviation analysis, statistically significant differences between the patients and control group were obtained for the lateral incisors and canines (p ≤ 0.0001) and greater differences were found for the tooth crowns and root tips.

Conclusions

Lateral incisors adjacent to PDCs have shorter roots than contra-lateral lateral incisors. Furthermore, there were morphological differences between lateral incisors and canines in subjects with unilateral PDCs.

The Association between Ponticulus Posticus and Dental Agenesis: A Retrospective Study

Objective:

Neural tube defects may increase the risk of an abnormal development of skull, vertebral column and teeth formation, including dental agenesis in non syndromic patients. The association between the presence of a congenital Dental Agenesis (DA) and the Atlantooccipital Ligament (AOL) calcification, known as “Ponticulus Posticus” (PP), as possible links can be investigated.

Design:

After a systematic review of the scientific literature on this topic, two independent examiners assessed the AOL calcification in lateral cephalograms of 350 non syndromic patients(7-21 years old). The results were compared with a control group (non syndromic patients, without congenital missing teeth).

Results:

The 16.3% of the population studied by cephalometric analysis revealed a prevalence rate of PP (both complete and partial) with a slight male predominance is seen, not statistically significant (χ square test = 0.09; p= 0.76). In both sexes complete PP is more observed. In the patients affected by DA the frequency of PP is the 66.6% (both complete than partial). The χ square test with Yates correction showed a significative difference(χ= 66.20; p value= 0.00) between PP in patients with DA compared to not affected by DA.

Conclusions:

PP is not an uncommon anomaly. Since orofacial pain like migraine and other symptoms are often associated to PP, during routine radiographic examination, if detected, it should be documented in patients’ health record and with symptoms, further investigation should be sought for. These findings encourage to think there’s an association between DA in non syndromic patients and neuro-crestal cells defects.

Whole exome sequencing in an Italian family with isolated maxillary canine agenesis and canine eruption anomalies

OBJECTIVE

The aim of this study was the clinical and molecular characterization of a family segregating a trait consisting of a phenotype specifically involving the maxillary canines, including agenesis, impaction and ectopic eruption, characterized by incomplete penetrance and variable expressivity.

DESIGN

Clinical standardized assessment of 14 family members and a whole-exome sequencing (WES) of three affected subjects were performed. WES data analyses (sequence alignment, variant calling, annotation and prioritization) were carried out using an in-house implemented pipeline. Variant filtering retained coding and splice-site high quality private and rare variants. Variant prioritization was performed taking into account both the disruptive impact and the biological relevance of individual variants and genes. Sanger sequencing was performed to validate the variants of interest and to carry out segregation analysis.

RESULTS

Prioritization of variants "by function" allowed the identification of multiple variants contributing to the trait, including two concomitant heterozygous variants in EDARADD (c.308C>T, p.Ser103Phe) and COL5A1 (c.1588G>A, p.Gly530Ser), specifically associated with a more severe phenotype (i.e. canine agenesis). Differently, heterozygous variants in genes encoding proteins with a role in the WNT pathway were shared by subjects showing a phenotype of impacted/ectopic erupted canines.

CONCLUSIONS

This study characterized the genetic contribution underlying a complex trait consisting of isolated canine anomalies in a medium-sized family, highlighting the role of WNT and EDA cell signaling pathways in tooth development.

Prevalence of foramen arcuale and its clinical significance: a meta-analysis of 55,985 subjects

OBJECTIVE

The foramen arcuale (FA) is a bony bridge located over the vertebral artery on the posterior arch of the atlas. The presence of an FA can pose a risk during neurosurgery by providing a false impression of a broader posterior arch. The aim of this study was to provide the most comprehensive investigation on the prevalence of the FA and its clinically important anatomical features.

METHODS

Major electronic databases were searched to identify all studies that reported relevant data on the FA and the data were pooled into a meta-analysis.

RESULTS

A total of 127 studies (involving 55,985 subjects) were included. The overall pooled prevalence of a complete FA was 9.1% (95% CI 8.2%–10.1%) versus an incomplete FA, which was 13.6% (95% CI 11.2%–16.2%). The complete FA was found to be most prevalent in North Americans (11.3%) and Europeans (11.2%), and least prevalent among Asians (7.5%). In males (10.4%) the complete FA was more common than in females (7.3%) but an incomplete FA was more commonly seen in females (18.5%) than in males (16.7%). In the presence of a complete FA, a contralateral FA (complete or incomplete) was found in 53.1% of cases.

CONCLUSIONS

Surgeons should consider the risk for the presence of an FA prior to procedures on the atlas in each patient according to sex and ethnic group. We suggest preoperative screening with computerized tomography as the gold standard for detecting the presence of an FA.

How common is ponticulus posticus on lateral cephalograms?

Background

Ponticulus posticus is an anomaly of first cervical vertebra visible on lateral cephalogram and has some serious medical and surgical implications. Unfortunately, it is often overlooked or undetected by orthodontists. The general objective of this study is to sensitize orthodontists about this anomaly by depicting its prevalence among a group of Nepalese orthodontic patients.

Methods

Four hundred and fourteen digital lateral cephalograms of orthodontic patients were retrieved from the archives of the department. The lateral cephalograms were carefully assessed for the presence of ponticulus posticus in the posterior spine of atlas vertebra by two investigators independently and the findings were recorded.

Results

Ponticulus posticus was observed in 35.7% of the cases, of which 30.9% had partial ponticulus posticus and 4.8% had complete ponticulus posticus. Even though there was some female predilection, no statistically significant association was found between gender of the patient and presence of ponticulus posticus.

Conclusion

Ponticulus posticus is a fairly common anomaly with more than one-third (35.7%) of a group of Nepalese orthodontic patients affected and is independent of gender. Since, this anomaly is associated with numerous medical conditions and has surgical implications, orthodontists should use lateral cephalogram as screening radiograph for this anomaly.

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-017-2494-z) contains supplementary material, which is available to authorized users.

Associations between occlusion, jaw relationships, craniofacial dimensions and the occurrence of palatally-displaced canines

BACKGROUND AND PURPOSE

Cephalometric and arch measurements might predict the occurrence of a palatally-displaced impacted maxillary canine (PDC). Despite their clinical importance, studies in this regard are limited and controversial.

METHODS

In this case-control study, 35 PDC patients and 77 controls aged over 13 years were examined. Eleven cephalometric measurements: N-S, ANS-PNS, ANS-N, S-N-ANS, facial angle (FH/NPog), SNA, SNB, Y-axis (SN/SGn), gonial angle, Go-Gn/SN, and Jarabak Index were performed. The maxillary and mandibular intermolar and interpremolar widths were measured. Patients' sagittal skeletal relationships and centric occlusions (molar) were measured by radiographic and cast examinations. The differences between the two groups in terms of the above-mentioned cephalometric and anatomic variables were assessed using Chi² and Mann-Whitney U-tests (α=0.05).

RESULTS

Chi² showed a significant negative association between dentoalveolar class I (molar) and PDC occurrence (P=0.018), but not between PDC and skeletal sagittal relationships. Facial angle (FH/NPog) and Y-axis (SN/SGn) were more obtuse in patients with PDC (P<0.05). No arch dimensions differed between the two groups.

CONCLUSIONS

PDC tends to accompany molar class II/III but is not associated with upper or lower jaw widths or lengths. Vertical dimensions might be smaller in PDC patients. Some variables were inconclusive and need future assessments.

Prevalence of C7 level anomalies at the C7 level: an important landmark for cervical nerve ultrasonography

BACKGROUND

Recently, various examination and intervention techniques using cervical nerve ultrasonography have been developed. The specific shapes of the C7 transverse process and vertebral artery in front of the C7 transverse process have become landmarks.

PURPOSE

To determine the prevalence of anomalies and anomalous vertebral artery entrances at the C7 transverse process.

MATERIAL AND METHODS

The records of patients who underwent plain or contrast-enhanced neck or cervical spine computed tomography (CT) were reviewed. The examinations were scored for the anomalous presence of anterior tubercles or cervical ribs as well as vertebral artery entrances in the C7 transverse process. The prevalence of anomalies was compared based on patient sex and age.

RESULTS

Evaluating the examinations from 2067 patients (1046 men; 1021 women), 1% of patients exhibited an anomalous presence of anterior tubercles, and 0.3% of patients displayed cervical ribs at the C7 transverse process. The prevalence of anomalies process was significantly higher in men aged less than 40 years than in older men (P < 0.001), whereas the prevalence was not higher in women aged less than 40 years than in older women. The prevalence of vertebral artery entry into the C7 transverse foramen was 0.6%.

CONCLUSION

Although an anomalous vertebral artery entry into the C7 transverse foramen was rare, the prevalence of an anomaly at the C7 transverse process was higher in men aged less than 40 years. Therefore, we recommend performing CT in younger men before cervical nerve ultrasonographic intervention to avoid misinterpretations at the cervical level.

Possible Further Evidence of Low Genetic Diversity in the El Sidrón (Asturias, Spain) Neandertal Group: Congenital Clefts of the Atlas

We present here the first cases in Neandertals of congenital clefts of the arch of the atlas. Two atlases from El Sidrón, northern Spain, present respectively a defect of the posterior (frequency in extant modern human populations ranging from 0.73% to 3.84%), and anterior (frequency in extant modern human populations ranging from 0.087% to 0.1%) arch, a condition in most cases not associated with any clinical manifestation. The fact that two out of three observable atlases present a low frequency congenital condition, together with previously reported evidence of retained deciduous mandibular canine in two out of ten dentitions from El Sidrón, supports the previous observation based on genetic evidence that these Neandertals constituted a group with close genetic relations. Some have proposed for humans and other species that the presence of skeletal congenital conditions, although without clinical significance, could be used as a signal of endogamy or inbreeding. In the present case this interpretation would fit the general scenario of high incidence of rare conditions among Pleistocene humans and the specific scenariothat emerges from Neandertal paleogenetics, which points to long-term small and decreasing population size with reduced and isolated groups. Adverse environmental factors affecting early pregnancies would constitute an alternative, non-exclusive, explanation for a high incidence of congenital conditions. Further support or rejection of these interpretations will come from new genetic and skeletal evidence from Neandertal remains.

Association between sella turcica bridging and palatal canine impaction

INTRODUCTION

The association of sella turcica bridging and various dental anomalies has been an area of interest for researchers. Based on the evidence of a common embryologic origin between sella turcica and the teeth, the objectives of this study were to measure the dimensions of sella turcica and to test whether an association exists between sella bridging and impacted canines.

METHODS

Orthodontic records comprising standard-quality lateral cephalograms and dental panoramic radiographs were selected. Thirty-one patients with palatally impacted canines (20 female, 11 male; mean age, 18.4 ± 8.9 years) and 70 controls with erupted canines (35 male, 35 female; mean age, 17.1 ± 7.5 years) were included in the study. Comparison of sella dimensions between the patients and the controls was carried out by independent sample t tests, whereas the association of sella bridging with impacted canines was analyzed using the chi-square test.

RESULTS

The frequencies of complete and partial calcification of sella in the patients were 8 (25.8%) and 17 (54.8%), respectively, whereas those in the controls were 0 and 36 (51.4%), respectively. The frequency of sella bridging was significantly higher in subjects with canine impaction than in the controls (P <0.001). The sagittal interclinoidal distance was found to be significantly reduced in the patients (P = 0.028). According to the statistical analysis, age and sex do not influence the dimensions and calcification of sella turcica.

CONCLUSIONS

Sella bridging is frequently found in patients with impacted canines. Hence, sella bridging can complement other diagnostic parameters in confirming the status of canine impaction.