A comparative study of cone-beam computed tomography and digital panoramic radiography for detecting pulp stones

A novel deep learning-based pipeline architecture for pulp stone detection on panoramic radiographs

OBJECTIVES

Pulp stones are ectopic calcifications located in pulp tissue. The aim of this study is to introduce a novel method for detecting pulp stones on panoramic radiography images using a deep learning-based two-stage pipeline architecture.

MATERIALS AND METHODS

The first stage involved tooth localization with the YOLOv8 model, followed by pulp stone classification using ResNeXt. 375 panoramic images were included in this study, and a comprehensive set of evaluation metrics, including precision, recall, false-negative rate, false-positive rate, accuracy, and F1 score was employed to rigorously assess the performance of the proposed architecture.

RESULTS

Despite the limited annotated training data, the proposed method achieved impressive results: an accuracy of 95.4%, precision of 97.1%, recall of 96.1%, false-negative rate of 3.9%, false-positive rate of 6.1%, and a F1 score of 96.6%, outperforming existing approaches in pulp stone detection.

CONCLUSIONS

Unlike current studies, this approach adopted a more realistic scenario by utilizing a small dataset with few annotated samples, acknowledging the time-consuming and error-prone nature of expert labeling. The proposed system is particularly beneficial for dental students and newly graduated dentists who lack sufficient clinical experience, as it aids in the automatic detection of pulpal calcifications. To the best of our knowledge, this is the first study in the literature that propose a pipeline architecture to address the PS detection tasks on panoramic images.

Cone-Beam Computed Tomography Assessment of the Prevalence and Association of Pulp Calcification with Dental and Periodontal Pathology: A Descriptive Study

Background/Objectives: Pulp stones (PSs) are calcified masses, with rounded or oval shapes, ranging from small particles to masses larger than the chamber and/or canals. There are limited data regarding the prevalence of pulp stones in the Iberian population. Our aim was to determine the prevalence of PSs, using CBCT, in an Iberian population, and its association with gender, age, tooth location (arch and hemiarch), dental group, the presence of caries, restorations, alveolar bone loss, and a history of orthodontic treatment. Methods: In total, 300 CBCTs were analyzed, selected from the database of the Dental Clinic of the University of Valencia. A total of 5485 teeth were included. The images were obtained by NewTom equipment and visualized using NNT software 11 by a single calibrated examiner in the axial, sagittal, and coronal planes. The Chi-square test, ANOVA, and t-test were used to analyze the study variables for a significance level of p < 0.05. Results: The prevalence of PSs was 88.3% from the total number of patients assessed and 61.2% from the total number of teeth assessed. No differences were found by gender or age. A significant association was found within tooth groups between arches and hemiarches. The proportion of PSs was 3.7 times higher in teeth with caries, 4.7 times higher in teeth with fillings, and 2.3 times higher in teeth with alveolar bone loss. Conclusions: PSs were more prevalent in molars. The presence of caries, fillings, and bone loss increased the chance of presenting PSs. Maxillary teeth had a higher prevalence of PSs than mandibular teeth.

Pulp stones and kidney stones-related gene: An investigation of single nucleotide polymorphisms in the gene encoding parathyroid hormone

Introduction

Pulp stones (PS), whose origins remain unclear, present a challenge for clinical practice in Endodontics. Similar to other calcifications, a relationship with parathyroid hormone is hypothesized.

Purpose

The aim of this study was to investigate the association between the presence of PS and kidney stones (KS) and single nucleotide polymorphisms (SNPs) in the parathyroid hormone (PTH) gene, which is related to KS.

Methods

This cross-sectional study included adults of both sexes, divided into groups: with PS and without PS. PS diagnosis was based on radiographic evaluation. Saliva samples were collected from all participants, and prior history of KS was recorded. The samples were processed, and genomic DNA was used to genotype the rs694, rs6256, and rs307247 SNPs. The Hardy-Weinberg equilibrium was assessed using the Chi-square test. Genotypic and allelic profiles under additive, dominant, and recessive models were evaluated using a univariate logistic regression model and the Wald test, with analyses conducted in SPSS® version 23.0. Additionally, Fisher's exact test was used to compare the haplotype frequencies. Statistical significance was set at 5 %.

Results

The study included 63 patients with PS and 54 without PS, with a mean age of 32.5 years. No statistically significant association was observed between the groups regarding the presence of KS. Allelic and genotypic analyses revealed no significant association (P > 0.05) between the presence of PS and SNPs analyzed in the groups studied.

Conclusion

None of the SNPs studied in the gene encoding PTH were associated with PS or KS.

Pulp calcification identification on cone beam computed tomography: an artificial intelligence pilot study

BACKGROUND

This study aims to verify the effectiveness of a deep neural network (DNN) in automatically identifying pulp calcification on cone beam computed tomography (CBCT) images.

METHODS

This study retrospectively analysed 150 CBCT images. Pulp calcification was identified and manually annotated by three endodontists with 10 years of experience. A DNN model based on the U-Net architecture was constructed to identify pulp calcification, and ten rounds of fourfold cross-validation were conducted. The model performance was evaluated using sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve (AUC).

RESULTS

The model achieved a sensitivity of 75.91 ± 2.84% in automatically identifying pulp calcification, with a specificity of 68.88 ± 2.35%, an accuracy of 72.78 ± 2.13%, and an AUC of 73.68 ± 3.09%. According to the ranking for diagnostic tests, the proposed method achieved a "good" grade for sensitivity, accuracy, and AUC and a "fair" grade for specificity.

CONCLUSIONS

The results indicate that the proposed method shows promise for identifying pulp calcification on CBCT images. Future research aims to expand the dataset and refine the model, thereby enhancing its clinical applicability. The integration of artificial intelligence into diagnostic and treatment systems is anticipated to increase the efficiency of diagnosing pulp calcification and assist dentists in assessing the difficulty of root canal treatment cases preoperatively.

CLINICAL REGISTRATION

Registration was performed on the Chinese Clinical Trial Registry ( https://www.chictr.org.cn/ ) (Registration number: ChiCTR2300077078, 27/10/2023) and National Medical Research Registry Information System ( https://www.medicalresearch.org.cn/ , 30/10/2023) (Number: MR-44-23-039664).

Distribution and influencing factors of pulp stones based on CBCT: a retrospective observational study from southwest China

BACKGROUND

Pulp stones are a type of pulp calcification, the presence of which tends to hinder endodontic treatment. Thus, this retrospective study aimed to analyze the distribution of pulp stones in the population in southwest China and identify the influencing factors.

MATERIALS

Cone-beam computed tomography (CBCT) scans of 5066 teeth of 200 patients (91 males and 109 females) aged 16-45 years were evaluated. Pulp stones were marked as either present or absent when distinct radiopaque masses were found in the pulp cavity, then evaluated the occurrence of pulp stones with regard to tooth type, sex, age group, and contact it with tooth status. The Pearson chi-square test and nonparametric test were used for statistical analysis.

RESULTS

Pulp stones were detected in 49.0% of patients and 7.4% of teeth, respectively. The incidence in females was 1.9 times higher than in males (OR = 1.9, 95% CI = 1.1-3.3, p = 0.001). Pulp stones were most prevalent in patients 36-45 years of age. Furthermore, in the age range of 16-45 years, the likelihood of finding pulp stones increased 1.1 times per year with age (OR = 1.1, 95% CI = 1.0-1.1, p = 0.032). A higher incidence of pulp stones was observed in the maxilla and molars. Of the 5066 teeth studied, pulp stones were more common in non-intact teeth.

CONCLUSION

Nearly half of the population in southwest China had pulp stones. Pulp stones were found significantly more often in females, maxilla, and non-intact teeth, and their frequency increased with age. For dentists, understanding the distribution of pulp stones is crucial for the proper design of root canal treatment (RCT).

TRIAL REGISTRATION

This study was approved by the Ethics Committee of the Affiliated Hospital of Stomatology, Southwest Medical University (certificate number: 20220818001).

Investigation of polymorphisms in BMP2, BMP4, SMAD6 and RUNX2 genes and pulp stones

This study aimed to assess the association between genetic polymorphisms in BMP2 (rs1005464 and rs235768), BMP4 (rs17563), SMAD6 (rs2119261 and rs3934908) and RUNX2 (rs59983488 and rs1200425) and pulp stones (PS). A total of 117 participants, consisting of 63 individuals with PS and 54 without PS, were included. Digital radiographs and a demographic/clinical questionnaire were used. Genomic DNA from salivary cells was genotyped via real-time polymerase chain reaction. Statistical analyses, including Chi-Square, Fisher's exact tests, Poisson regression and dimensionality reduction, were conducted. The rs2119261 polymorphism in the SMAD6 gene showed an association with genotype distribution in the recessive model (p = 0.049). The T-T haplotype in the SMAD6 gene (rs2119261 and rs3934908) was more prevalent in the control group and significantly linked with PS (p = 0.029). No associations were found between PS risk and genetic polymorphisms in BMP2, BMP4 and RUNX2. Polymorphisms in the SMAD6 gene were associated with PS.

Identification and classification of pulp calcifications in posterior teeth according to dental condition using digital panoramic radiography and cone beam CT

OBJECTIVE

To compare digital panoramic radiography (DPR) and cone beam CT (CBCT) in the detection and classification of pulp calcifications in posterior teeth in relation to tooth condition and its location.

METHODS

Two hundred and fifty patients with simultaneous DPR and CBCT scans were selected from a dental image bank. For each posterior tooth, its condition was registered (healthy, restored, or decayed). The presence of calcifications was assessed and classified according to location (coronal or radicular) and type (total obliteration, partial obliteration, narrowing, and no calcification). Chi-square and McNemar tests were used to compare DPR and CBCT results, with a significance level of 5%. DPR diagnostic values were calculated using CBCT as reference.

RESULTS

Decayed and restored teeth showed a significantly (P < .001) higher prevalence of pulp calcifications than healthy teeth in both imaging exams. There was a significant discrepancy between the imaging modalities in the identification of calcifications (P < .001), especially for radicular calcifications of maxillary teeth (DPR = 55.2%; CBCT = 30.9%). In the case of coronal calcifications, there was a greater discrepancy between CBCT and DPR in the mandibular teeth (10.7%) than in the maxillary teeth (7.7%). Overall, DPR presents higher sensitivity (0.855) than specificity (0.483) for pulp calcifications detection.

CONCLUSION

DPR considerably overestimates pulp calcifications in posterior teeth, as compared to CBCT. A higher prevalence of pulp calcifications is related to decayed and restored teeth.

Pulp stones in unerupted teeth: a retrospective analysis using cone-beam computed tomography

BACKGROUND

A pulp stone is a calcified mass that develops in the dental pulp of any tooth. Despite many studies examining the relationship between pulp stone formation and non-oral factors, the methods used in these studies have been unable to explain the exact role of these factors alone as distinct from probable effects within the oral cavity environment. Considering that totally unerupted (impacted or developing) teeth are unexposed to the oral cavity's environmental and functional conditions, they provide a more suitable material for studying the effects of these non-oral factors on pulp stone formation. This research study aimed to investigate pulp stones in unerupted teeth and the associated factors in a Saudi subpopulation.

METHODS

The study included 644 cone-beam computed tomography images, with 496 (50.9%) maxillary and 479 (49.1%) mandibular teeth. Of the investigated patients, 293 (45.5%) were men, and 351 (54.5%) were women. The age range was 15-76 years. A chi-square test was used to investigate the associations between pulp stones and age, gender, and history of systemic disease and chronic medication use.

RESULTS

Pulp stones in unerupted teeth were present in 24.2% of the examined dental jaws and 18.6% of the examined teeth. There was no statistically significant relationship between pulp stones and gender (p > 0.05). A significantly greater percentage of pulp stones were found with increasing age (p = 0.000). Additionally, a significantly increased number of pulp stones was observed in patients with systemic diseases and chronic medications (p < 0.05).

CONCLUSIONS

The results support the idea that pulp stones can be present in any type of unerupted tooth. This study provides additional evidence of the increased incidence of pulp stones with age, systemic disease, and chronic medications.

Prevalence and Association of Calcified Pulp Stones with Periodontitis: A Cone-Beam Computed Tomography Study in Saudi Arabian Population

This study aimed to identify the prevalence and association of periodontitis and pulp stone (PS) along with the clinical variables. This study assessed the cone-beam computed tomography (CBCT) records to identify the presence of PS and clinical periodontitis records were used to determine the stages of periodontitis. The Chi-square test was used to evaluate the relationship between study parameters. Logistic regression was used to determine the association between PS and periodontitis. A total of 228 CBCT records were conveniently selected for this study based on the inclusion and exclusion criteria. Cohen's kappa analysis showed near to perfect scores for both examiners. The Chi-square test showed that CBCT records from the age range 41-50 years, male patients, and stage II of periodontitis prevalently showed pulp stones; however, there were no significant differences observed between the PS and clinical variables. However, gender, involvement of tooth, and stages of periodontitis showed significant distribution of the PS. Logistic regression showed that the stages of periodontitis showed no significant association with PS in patients with periodontitis. Moreover, multivariate odds ratio adjustment did not alter the outcome. Periodontitis is not associated with the presence of PS in the current population.

Cone-Beam Computed Tomography-Based Investigation of the Prevalence and Distribution of Pulp Stones and Their Relation to Local and Systemic Factors in the Makkah Population: A Cross-Sectional Study

Objectives This study aimed to assess the prevalence and distribution of dental pulp stones and evaluated their possible associations with local and systemic factors in the Makkah population in Saudi Arabia. Materials and methods Archived cone-beam computed tomography (CBCT) images for 390 patients, from the electronic health records (EHR) in the Dental Teaching Hospital, Umm Al-Qura University, were used. Images were examined in all planes (coronal, sagittal, and axial) for a discrete radiopaque mass in the pulp of all teeth, in both arches. The teeth conditions (the presence of caries, restoration, the periodontal condition, and the presence of pulp stones) were recorded. Additional patient information, including age, gender, and medical condition, was obtained from the patients' archived files. The collected data were statistically analyzed using the Statistical Package for Social Sciences (SPSS) (IBM SPSS Statistics, Armonk, NY) software; a p-value of ≤ 0.05 is considered statistically significant. Results Pulp stone prevalence was 78.97% of the subjects (308 out of 390) and 15.92% of the examined teeth (1644 out of 10326). There were statistically significant differences regarding nationality (p=0.043) and age (p=0.023) but no significant difference between males and females (p=0.876), maxillary and mandibular teeth (p=0.392), and right and left sides (p=0.222) in pulp stone prevalence. Significant differences were found between pulp stone prevalence of sound versus and carious and restored teeth and between periodontally affected teeth and periodontally healthy teeth (p=0.031). Conclusion The prevalence of pulp stones in the Makkah population is high. A positive association was found between nationality, age, tooth restorations, caries, periodontal diseases, and pulp stone prevalence, but no correlation was found with patients' health or gender. The molars were the most affected teeth, while the incisors were the least.

The Study and Relevance of Pulp Chamber Anatomy in Endodontics - A Comprehensive Review

With the ever-increasing understanding of tooth anatomy, there is a renewed focus on the pulp chamber as an important component of the root canal system. For example, the pulp chamber is of critical relevance during diagnostic procedures such as pulp sensibility tests, deep caries removal, vital pulp treatments, access cavity preparation, tooth whitening, tooth restoration as well as methods for examining the floor of the pulp chamber to aid the detection of root canal orifices or the presence of perforations and cracks. The more recent concept of minimal invasive endodontics has also created a need to understand better the anatomy of the pulp chamber. The purpose of this article is to discuss the research methods used to study pulp chamber anatomy and the significance of the pulp chamber in endodontic research and clinical practice. In addition, directions for future research are emphasised.

The prevalence of pulp stones in a Turkish paediatric cohort from the Isparta district: an 8-year retrospective radiographic study

PURPOSE

To evaluate the prevalence of pulp stones in a Turkish paediatric cohort from the Isparta district using panoramic radiographs.

METHODS

Panoramic radiographs of 19,857 children and adolescents between the ages of 9 and 18 years were retrospectively analysed to determine the prevalence and distribution of pulp stones. Teeth with pulp stones were classified in terms of dentition, location, dental status and complete or incomplete root formation. Statistical analysis was carried out by applying Chi‑square and Mann-Whitney U. Univariate logistic regression analysis was applied to determine the factors affecting pulp stone status. Differences were considered as significant when p < 0.05.

RESULTS

Out of a total of 19,857 patients, pulp stones were identified in 6.5%. Among the 548,415 teeth examined, 0.96% had pulp stones. The incidence of pulp stones in girls (7.4%) was higher than in boys (5.7%) (p < 0.001). The prevalence of pulp stones increased with age and was significantly higher in molar teeth. A significant difference existed in the incidence of pulp stones according to the jaws (p < 0.001). In both jaws, no statistically significant difference was observed in terms of teeth with pulp stones being on the right and left (p = 0.834). Of molars with pulp stones, 91.8% had completed root formation. The majority of patients (37.7%) had pulp stones in four teeth.

CONCLUSION

Knowing the incidence of pulp stones in paediatric patients by dentists, endodontists, and paediatric dentists will help prevent complications that may occur during applications by facilitating the determination of appropriate methods, especially during endodontic procedures.

Three-dimensional analysis for detection of pulp stones in a Saudi population using cone beam computed tomography

PURPOSE

To assess the prevalence and distribution of pulp stones in a Saudi population.

METHODS

A cone beam computed tomography (CBCT) analysis of 150 upper and 150 lower dental arches was performed. The relationships between pulp stones and age, sex, tooth type, dental arch, orthodontic treatment, caries, and restoration were statistically examined (P < 0.05).

RESULTS

A total of 295 dental arches (98.3%) had at least one pulp stone, and the prevalence was higher in the maxillary teeth (56.2%) than in the mandibular teeth (48.1%) (P = 0.0003). Men were more likely to have pulp stones than women (P = 0.011 for the maxilla, P < 0.0001 for the mandible). Furthermore, age and orthodontic treatment had no significant effects on the incidence of pulp stones (P > 0.05). A higher occurrence of pulp stones was observed in the first molars (>91%), and in carious and restored teeth when compared to intact teeth (P < 0.05).

CONCLUSION

Pulp stones were more prevalent in the upper dental arches, first molars, and carious and restored teeth, as well as in the male population, and were not associated with age or orthodontic treatment.

Association between the prevalence of pulp stones and calcified atherosclerotic plaques: a systematic review and meta-analysis

OBJECTIVE

To evaluate the association between the prevalence of pulp stones (PS) in permanent teeth and calcified atherosclerotic plaques (CAP).

METHODS

An electronic search was performed in 10 databases to locate observational studies that investigated the association between PS in permanent teeth and CAP, published until March 2022. Two reviewers performed the search, selection and extraction of data from eligible studies. The individual risk of bias of eligible studies was assessed using the JBI Critical Appraisal Tools. The meta-analysis was conducted using fixed and random effects and odds ratio (OR) as an effect measure with a 95% confidence interval (CI). The heterogeneity between the studies was quantified using the I² test. The certainty of evidence was evaluated using the GRADE approach.

RESULTS

The electronic search resulted in 2968 records, of which only 7 studies were considered eligible. The total sample consisted of 3770 participants from 5 countries. All studies showed biases of confounding factors and exposure assessment. Based on six studies and with very low certainty of evidence, the meta-analysis showed that patients with PS were more likely to also have CAP in carotid or coronary arteries (OR: 1.70; 95% CI: 1.21; 2.38, I² = 0%).

CONCLUSIONS

Limited evidence suggests that there is a positive association between the prevalence of PS in permanent teeth detected using panoramic radiography and CAP in the coronary or carotid arteries.

Cone beam computed tomography assessment of the prevalence and association of pulp calcification with periodontitis

Periodontitis has a known association with pathological calcification in the cardiovascular system. Considering the close anatomic and circulatory association between dental pulp and the periodontium, this study aimed to evaluate the prevalence of pulp calcification (PC) under different periodontal conditions, as well as the associations of PC with the degree of periodontal damage, via cone beam computed tomography (CBCT) examination. In this study, 55 patients were categorized into three groups according to periodontal condition: group 1 (healthy controls), group 2 (periodontitis stage I-II), and group 3 (periodontitis stage III-IV). PC and radiographic bone loss (RBL) was assessed by CBCT in sagittal, axial, and coronal views, and statistical analyses were conducted. PC was identified in 378 of 1170 teeth (32.3%). The prevalence significantly differed among the three groups (P < 0.001). Group 2 had a 2.43-fold (P < 0.001, 95% confidence interval [CI] 1.64-3.61) higher risk of PC than group 1; and the risk of PC was 3.04-fold (P < 0.001, 95% CI 2.06-4.48) higher in group 3 than group 1. Teeth with more severe RBL exhibited a higher prevalence of PC (P < 0.001). Molar teeth had a higher risk of PC than incisors and premolars. In conclusion, the occurrence of PC is related to the periodontal state, and the prevalence of PC is higher in teeth with periodontitis; tooth type and periodontitis status are important risk factors for PC.

Detecting calcified pulp stones in patients with periodontal diseases using digital panoramic and periapical radiographies

Background/purpose

Pulp stones are discrete calcified masses appearing in the dental pulp of healthy, disease and unerupted teeth. They are presented freely within the pulp tissue or attached and embedded in any part of coronal and radicular dentin. Here, the purposes of this study were to identify the presence of pulp stones in periodontal patients using digital panoramic and periapical radiographies, and to determine the association with gender, age, tooth type and dental arch.

Materials and methods

This is a retrospective study on selected records of 465 dental samples obtained between January and December, 2020. Data were collected from patients diagnosed with generalized chronic periodontitis and accepted the full periodontal treatment covered by the Government's Periodontal Health Care Program. Their digital panoramic (DPR) examination and full mouth periapical radiographic (DPA) examination (including 12 periapical and 4 bitewing images) were performed at the Outpatient Clinics of the Department of Stomatology, Taichung Veterans General Hospital. Patients were segregated into various groups according to their age, gender and tooth locations. All radiographic images were examined by a dental radiologist and two dentists to identify the presence of pulp stone calcifications and their associated factors using the Sirona applications software. Records were analyzed using SPSS version 22.0 based on tests of Pearson Chi-square and McNemar correlation.

Results

From 271 males and 194 females, a total of 465 DPR and 7440 DPA radiographs were studied. Pulp stone calcifications were identified in 270 (58.0%) subjects in DPR images and 348 (74.8%) subjects in DPA images (for 1 or more teeth per subject). We detected calcified opacities in 1031 teeth with DPR images and in 1326 teeth with DPA images from a total of 12,407 teeth. The incidence of pulp stones was similar across genders, but different in tooth locations and dental arch sextant. Moreover, pulp stones were detected more often on maxillary molars and subjects of old ages (>40 years). Digital panoramic and periapical radiography showed significant differences in the detection of pulp stone calcifications (P < 0.05), and detected better with digital periapical radiography examination.

Conclusion

We found 58.0% (n = 645) of our patients with pulp stones using digital panoramic radiography, and 74.8% using digital periapical radiography. Regarding individual teeth, only 8.5% of pulp stones were observed in digital panoramic radiography and 10.6% in digital periapical radiography. Pulp stones were more often seen in maxillary molar teeth and old patients of ages >40 years old using periapical radiography examination especially in those patients with periodontally condition. As a two-dimensional imaging system, digital periapical radiography is recommended for a definitive and routine assessment in patients suspected of hard tissue abnormality and pulp calcification formation.

Evaluation of the relation between the pulp stones and direct restorations using cone beam computed tomography in a Turkish subpopulation

Objectives

This study aimed to assess the presence of pulp stones through an examination of cone beam computed tomography images and correlate their prevalence with age, sex, dental arch and side, tooth type, and restoration type and depth.

Materials and Methods

Cone beam computed tomography images obtained from 673 patients and archival data on 11,494 teeth were evaluated. The associations of pulp stones with age, sex, dental arch and side, tooth type, and restoration type and depth were noted. All the measurements were subjected to a χ² test and one sample χ² test (p < 0.05).

Results

In the study group, 163 (24.2%) patients and 379 (3.3%) teeth had at least one pulp stone. The pulp stone frequency in those aged 30–39 years was significantly greater than in those aged 18–29 and ≥ 60 years, and the frequency was higher in females than in males (p < 0.05). The highest prevalence of pulp stones was found in maxillary dental arches and molar teeth (p < 0.05). Pulp stones were significantly more common in medium-depth restorations (p < 0.05).

Conclusions

Maxillary molar teeth, medium-depth restorations, individuals aged 30–39 years and females had a greater percentage of pulp stones.

Micro-CT assessment of radicular pulp calcifications in extracted maxillary first molar teeth

OBJECTIVES

The present study aimed to evaluate the frequency, position, and length of radicular pulp calcifications in three-rooted maxillary first molars using micro-computed tomography.

MATERIALS AND METHODS

Two hundred three-rooted maxillary first molars were scanned at a pixel size of 10 µm and reconstructed using similar parameters. Three-dimensional models of the mesiobuccal (MB1, MB2, MB3), distobuccal (DB), and palatal (P) canals were qualitatively evaluated for discontinuity in the canal path. Transaxial and sagittal cross-sectional images of the roots were further screened, and the complete obliteration of the canal lumen by pulp calcification was identified when the canal had similar radiodensity to the surrounding dentine. Then, the number, position, and length of the calcifications were recorded for each root. Intra-observer agreement was performed using Cohen's kappa test, while one-way ANOVA and Duncan tests compared the lengths of calcifications among the canals, with α = 5%.

RESULTS

Intra-observer agreement was perfect for identification of pulp calcifications (ĸ = 1.0; p = 0.000). MB2 and MB3 canals accounted for the highest percentage frequency of calcifications distributed throughout the canal path. In the MB1, DB, and P canals, they occurred mainly at the apical third. Lengths of calcifications were greater in the MB3 (0.89 ± 0.81 mm) and MB2 (0.82 ± 0.93 mm) canals than in the MB1 (0.39 ± 0.32 mm), DB (0.34 ± 0.22 mm), and P (0.28 ± 0.22 mm) canals (p < 0.05).

CONCLUSION

MB2 and MB3 canals accounted for the highest frequency and length of radicular pulp calcifications. In the MB1, DB, and P canals, calcifications occurred mostly at the apical third, while in the MB2 and MB3, most of calcifications were observed at the orifice level and along the canal path.

CLINICAL RELEVANCE

In maxillary first molars, radicular pulp calcifications are mainly located at the apical third of the MB1, DB, and P canals, while in the MB2 and MB3 canals, most of them are at the orifice level or along the canal path.

Does dose optimisation in digital panoramic radiography affect diagnostic performance?

OBJECTIVES

To compare the overall diagnostic performance of digital panoramic radiographs obtained with low-dose protocols and to estimate the absorbed dose in the head and neck.

MATERIALS AND METHODS

Forty-eight panoramic radiographs were obtained from eight imaging phantoms using six exposure protocols of progressively lower tube voltages (kVp) and currents (mA), as follows: (1) 70 kVp and 12.5 mA, (2) 66 kVp and 10 mA, (3) 66 kVp and 8 mA, (4) 66 kVp and 5 mA, (5) 66 kVp and 4 mA and (6) 66 kVp and 3.2 mA. Five oral radiologists independently evaluated the images and reported all detectable radiographic findings. Intra-examiner reproducibility was assessed by re-evaluation of 25% of the images. The data were analysed using the McNemar and weighted Kappa tests. Absorbed doses of the six protocols were obtained from thermoluminescent dosimeters placed inside a Rando phantom and compared using one-way ANOVA with post hoc Tukey (α = 0.05).

RESULTS

The overall diagnostic performance of panoramic radiographs obtained with low-dose protocols did not differ from that of panoramic radiographs obtained with the highest dose (p > 0.05). Moreover, substantial agreement was observed between all protocols. Protocol 1 resulted in the highest absorbed dose and protocols 4, 5 and 6 in the lowest absorbed doses, with the difference being significant (p ≤ 0.05).

CONCLUSION

Although digital panoramic radiography is considered a relatively low-dose examination, the radiation dose can be further reduced without negatively affecting its overall diagnostic performance.

CLINICAL RELEVANCE

Considering the risks associated with X-rays, digital panoramic radiographs can be obtained at even lower exposure levels.

Evaluation of the relationship between sleep bruxism and pulpal calcifications in young women: A clinico-radiological study

PURPOSE

This study was performed to investigate the relationship between sleep bruxism (SB) and pulpal calcifications in young women.

MATERIALS AND METHODS

A total of 100 female participants between 20 and 31 years of age who were referred to our radiology clinic for a dental check-up, including 59 SB and 41 non-SB patients, were sampled for the analysis. SB was diagnosed based on the American Academy of Sleep Medicine criteria. All teeth were evaluated on digital panoramic radiographs to detect pulpal calcifications, except third molars, teeth with root canal treatment, and teeth with root resorption. Binary logistic regression analysis was used to determine the risk factors for pulpal calcifications. The Spearman correlation coefficient was applied and the Pearson chi-square test was used for categorical variables. To test intra-examiner reproducibility, Cohen kappa analysis was applied. P values <.05 were considered to indicate statistical significance.

RESULTS

A total of 2800 teeth were evaluated (1652 teeth from SB patients and 1148 from non-SB patients), and 61% of patients had at least 1 dental pulpal calcification. No statistically significant relationship was found between SB and pulpal calcifications (P>0.05). In SB patients, the total number of pulpal calcifications was 129, while in non-SB patients, it was 84. Binary logistic analysis showed that SB was not a risk factor for the presence of pulpal calcifications (odds ratio, 1.19; 95% CI, 0.52-2.69, P>.05).

CONCLUSION

No relationship was found between SB and pulpal calcifications.