Pre-surgical treatment planning for maxillary canine impaction using two- versus three-dimensional imaging

AIM: To compare surgical treatment planning for impacted maxillary canines between two-dimensional (2D) versus three-dimensional (3D) diagnostic radiographs, and to evaluate the influence of the imaging modality on treatment planning. SUBJECTS AND METHOD: Thirty-two subjects (19 females, 13 males) with a mean age of 25 years (SD 14 years). In total, 39 impacted canines were referred for surgical intervention. Two sets of radiographic information were obtained. The first set was panoramic radiographs and the second 3D volumetric images obtained from a cone beam computed tomography (CBCT) scan. Both 2D and 3D pre-operative radiographic diagnostic sets were produced and subsequently analyzed by four orthodontists and two oral surgeons. Peri-operative evaluations were conducted by the treating surgeon. A short post-operative recall after one week was recorded. RESULTS: The observers had a significantly higher level of confidence in their CBCT image-based therapy plans than the 2D radiograph-based plans (P < 0.001). The radiographically based diagnosis of type of impaction, canine crown position in the sagittal and axial planes, contact relationship, and lateral incisor root resorption were significantly different between the 2D versus 3D datasets. In contrast, pre- and perioperative evaluations were not significantly different when using 2D or 3D information. The use of 3D images resulted in extra diagnostic information compared to 2D in 31 per cent of the cases. The evaluation of this study recommended the use of CBCT in 61 per cent of the impacted canine cases. In 79 per cent of the evaluations, the observers changed the therapeutic approach based on 3D information. CONCLUSION: CBCT is recommended for the surgical intervention in canine impaction. CBCT images are useful for optimal treatment planning in cases of canine impaction and root resorption of adjacent incisors.status: publishe

Raman Micro-Spectroscopy of Dental Pulp Stem Cells: An Approach to Monitor the Effects of Cone Beam Computed Tomography Low-Dose Ionizing Radiation

© 2018, © 2018 Taylor & Francis. The objective of this study was to determine the molecular and biochemical changes in dental pulp stem cells (DPSCs) due to consecutive low-dose ionizing radiation exposures using label-free Raman micro-spectroscopy (RMS). Ionizing radiation produces biological damage leading to health effects of varying severity. The effects and subsequent health implications caused by exposure to low-dose radiation, such as diagnostic exposure, remain ambiguous. We identified Raman biomarkers characteristic to low-dose cone beam computed tomography (CBCT) irradiation of the DPSCs. The biomarkers were monitored inside the cells using the relative intensity distribution of the 785 and 1734 cm −1 bands. The control cells presented a higher relative intensity of the nucleic acid specific Raman bands, whereas the irradiated cells revealed an increased intensity of the lipid-induced bands. The results obtained in this study demonstrate the capability of RMS for the detection of cell response to diagnostic radiation dose levels. This may indicate the potential of the technique for future applications such as monitoring the radiation responses in pediatric patients suffering repeated radiological exposures.status: publishe

Irradiation provided by dental radiological procedures in a pediatric population

BACKGROUND: Children are more sensitive to ionizing radiation effects due to their high radiosensitivity. PURPOSE: To estimate doses and risks for dental radiological examinations in children. MATERIAL AND METHODS: A pediatric population consisting of 7150 children and young adults which underwent 12252 dental radiological examinations (4220 intraoral, 1324 cephalometric, 5284 panoramic radiographs and 1424 CBCTs) within two years were included. Two groups were studied: CBCT group (exposed to CBCT ± conventional radiographs) and 2D group (exposed only to 2D radiological examinations). The effective doses were corrected according to age at exposure and settings parameters (mA;FOV) by using logarithmic fit equations for dose interpolation. The individual cumulative dose, per-caput collective dose and radiation risk were calculated for each group. RESULTS: The median effective and cumulative doses for conventional radiographs were lower than 20 μSv and did not vary with age. Children exposed to CBCT had a higher median effective dose (127.2 μSv) and cumulative dose (156.5 μSv) with a significant increased cumulative dose between 11 and 14 years. The CBCT contributed with 70% to the collective dose and per caput collective dose was 184 μSv for CBCT exposures. The Life Attributable Risk (LAR) and Relative Radiation Level (RRL) were significantly higher for children exposed to CBCT under the age of 18. The highest radiation dose for CBCT was equivalent with 34.1 days of natural background radiation and it was found for ages between 11 and 15. CONCLUSION: The CBCT doses and radiation risk vary but remain in the lower levels of the relative risk of medical exposures.status: publishe

Cone-beam CT in paediatric dentistry: DIMITRA project position statement

DIMITRA (dentomaxillofacial paediatric imaging: an investigation towards low-dose radiation induced risks) is a European multicenter and multidisciplinary project focused on optimizing cone-beam CT exposures for children and adolescents. With increasing use of cone-beam CT for dentomaxillofacial diagnostics, concern arises regarding radiation risks associated with this imaging modality, especially for children. Research evidence concerning cone-beam CT indications in children remains limited, while reports mention inconsistent recommendations for dose reduction. Furthermore, there is no paper using the combined and integrated information on the required indication-oriented image quality and the related patient dose levels. In this paper, therefore, the authors initiate an integrated approach based on current evidence regarding image quality and dose, together with the expertise of DIMITRA's members searching for a state of the art. The aim of this DIMITRA position statement is to provide indication-oriented and patient-specific recommendations regarding the main cone-beam CT applications in the pediatric field. The authors will review this position statement document when results regarding multidisciplinary approaches evolve, in a period of 5 years or earlier.status: publishe

Variation in costs of cone beam CT examinations among healthcare systems

Objectives: To analyse the costs of cone beam CT (CBCT) in different healthcare systems for patients with different clinical conditions. Methods: Costs were calculated for CBCT performed in Cluj (Romania), Leuven (Belgium), Malmö (Sweden) and Vilnius (Lithuania) on patients with (i) a maxillary canine with eruption disturbance, (ii) an area with tooth loss prior to implant treatment or (iii) a lower wisdom tooth planned for removal. The costs were calculated using an approach based on the identification, measurement and valuation of all resources used in the delivery of the service that combined direct costs (capital equipment, accommodation, labour) with indirect costs (patients’ and accompanying persons’ time, ‘‘out of pocket’’ costs for examination fee and visits). Results: The estimates for direct and indirect costs varied among the healthcare systems, being highest in Malmö and lowest in Leuven. Variation in direct costs was mainly owing to different capital costs for the CBCT equipment arising from differences in purchase prices (range J148 000–227 000). Variation in indirect costs were mainly owing to examination fees (range J0–102.02). Conclusions: Cost analysis provides an important input for economic evaluations of diagnostic methods in different healthcare systems and for planning of service delivery. Additionally, it enables decision-makers to separate variations in costs between systems into those due to external influences and those due to policy decisions. A cost evaluation of a dental radiographic method cannot be generalized from one healthcare system to another, but must take into account these specific circumstances

Method validation to assess in vivo cellular and subcellular changes in buccal mucosa cells and saliva following CBCT examinations

OBJECTIVES: Cone-beam CT (CBCT) is a medical imaging technique used in dental medicine. However, there are no conclusive data available indicating that exposure to X-ray doses used by CBCT are harmless. We aim, for the first time, to characterize the potential age-dependent cellular and subcellular effects related to exposure to CBCT imaging. Current objective is to describe and validate the protocol for characterization of cellular and subcellular changes after diagnostic CBCT. METHODS: Development and validation of a dedicated two-part protocol: 1) assessing DNA double strand breaks (DSBs) in buccal mucosal (BM) cells and 2) oxidative stress measurements in saliva samples. BM cells and saliva samples are collected prior to and 0.5 h after CBCT examination. BM cells are also collected 24 h after CBCT examination. DNA DSBs are monitored in BM cells via immunocytochemical staining for γH2AX and 53BP1. 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) and total antioxidant capacity are measured in saliva to assess oxidative damage. RESULTS: Validation experiments show that sufficient BM cells are collected (97.1 ± 1.4 %) and that γH2AX/53BP1 foci can be detected before and after CBCT examination. Collection and analysis of saliva samples, either sham exposed or exposed to IR, show that changes in 8-oxo-dG and total antioxidant capacity can be detected in saliva samples after CBCT examination. CONCLUSION: The DIMITRA Research Group presents a two-part protocol to analyze potential age-related biological differences following CBCT examinations. This protocol was validated for collecting BM cells and saliva and for analyzing these samples for DNA DSBs and oxidative stress markers, respectively.status: publishe

Quantification of DNA Double Strand Breaks and Oxidation Response in Children and Adults Undergoing Dental CBCT Scan

Assessing the possible biological effects of exposure to low doses of ionizing radiation (IR) is one of the prime challenges in radiation protection, especially in medical imaging. Today, radiobiological data on cone beam CT (CBCT) related biological effects are scarce. In children and adults, the induction of DNA double strand breaks (DSBs) in buccal mucosa cells and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) and antioxidant capacity in saliva samples after CBCT examination were examined. No DNA DSBs induction was observed in children nor adults. In children only, an increase in 8-oxo-dG levels was observed 30 minutes after CBCT. At the same time an increase in antioxidant capacity was observed in children, whereas a decrease was observed in adults. Our data indicate that children and adults react differently to IR doses associated with CBCT. Fully understanding these differences could lead to an optimal use of CBCT in different age categories as well as improved radiation protection guidelines.status: publishe

Lateral Cephalometric Analytical Uses for Temporomandibular Joint Disorders: The Importance of Cervical Posture and Hyoid Position

The temporomandibular joint disorder (TMD) is a syndrome that affects the masticatory muscles and temporomandibular joint (TMJ). Its pathophysiology is not yet fully known. Cephalometric analysis is used for routine evaluation regarding orthodontic treatment and other purposes. The aim of this study was to assess if using cephalometric analysis and TMJ conservative therapy to evaluate the hyoid bone position and the cervical posture reduced symptoms in adults with TMDs compared to no intervention. The authors conducted a systematic review of the literature (PubMed, Cochrane, Web of Science, Scopus, and Embase) for clinical studies of TMDs with conservative treatment and lateral cephalometric analysis of the hyoid and cervical posture. To assess the risk of bias for non-randomized clinical trials ROBINS-I tool was used. Out of 137 studies found, 6 remained to be included. Most of them found a link between TMD and lateral cephalometric analysis, but there was a high risk of bias. This review found a possible link between TMDs, the neck and cervical posture. There is a benefit reported regarding the use of the lateral cephalometry as a treatment, but more extensive prospective randomized clinical trials are necessary to be able to draw definitive conclusions