A historical review of the effects of dental radiography on pregnant patients.

BACKGROUND: The safety of dental radiography performed on pregnant patients has been a controversial topic since the 1960s. This review synthesizes and consolidates findings, from 1957 through 2021, of the effects dental ionizing radiation could have on a pregnant patient and in utero birth defects. TYPES OF STUDIES REVIEWED: Using PubMed, the following key words were searched: pregnancy, radiology, radiograph, radiation dose, fetus, x-ray, and dental. Criteria evaluation was done on the basis of availability, completeness, quality, relevance, technicality (that is, dental radiography), topicality (that is, pregnant patients), and usability. These results were then filtered on the basis of quantitative and qualitative data as well as the period (decades within the historical framework). The final selection of relevant literature consisted of various studies including cohort studies, systematic reviews, meta-analyses, case reports, and other narrative reviews. RESULTS: If properly performed, the amount of ionizing radiation produced during dental radiographic procedures is so low that it is unlikely to reach the teratogenic threshold. Thus, dental ionizing radiation is unlikely to cause in utero birth defects because it has been detected to have a deterministic (not stochastic) effect. With this information and historical context, this article shows that necessary dental radiography is safe at any stage during pregnancy, as long as proper safety equipment is appropriately used. CONCLUSIONS AND PRACTICAL IMPLICATIONS: As technology advances, more research can further clarify ionizing radiation safety for pregnant patients and its potential effects on in utero birth defects, improving overall oral health care. The dental community must remain educated about current ionizing radiation safety guidelines to make better-informed decisions and successfully provide proper oral health care to pregnant patients.

Thyroid Collars in Dental Radiology: 2021 Update.

Background: In 2013, the American Thyroid Association (ATA) issued a "Policy Statement on Thyroid Shielding During Diagnostic Medical and Dental Radiology." The recently updated National Council on Radiation Protection and Measurement Radiation Protection in Dentistry and Oral and Maxillofacial Imaging (NCRP Report No. 177) prompts this review of progress related to patient thyroid shielding since the ATA statement was published. Summary: Relevant publications appearing since the ATA statement were identified by querying PubMed for "thyroid and dental and (collar or shielding)" and substituting specific dental radiographic procedures in the search. The search was expanded by reviewing the cited papers in the PubMed-retrieved papers and by use of the Web of Science to retrieve papers citing the PubMed retrieved publications. Although many quantitative studies have appeared reflective of current dental radiographic instrumentation and practice, much more can be done to foster minimizing radiation to the thyroid. Conclusions: We list seven areas that should be pursued. Among them are harmonizing guidelines for the use of thyroid collars based on the recent studies and a comprehensive survey of current dental radiological practice patterns.

Dental Radiographs for Age Estimation in US Asylum Seekers: Methodological, Ethical, and Health Issues.

Unaccompanied migrant children seeking asylum status in the United States are often forced to undergo dental radiographs, or x-rays, to verify that they are younger than 18 years.The application of third molar dental radiographs is methodologically flawed and should not be employed as a determinant of chronological age. Furthermore, the use of such tests without obtaining informed consent from either the youth or an objective advocate is unethical.Finally, the legal and health consequences of these inappropriately applied tests are severe and jeopardize the safety and security of these vulnerable minors.

Cuantificación de la distorsión presente en la radiografía posteroanterior de cráneo / Quantification of the distortion present in the postero-anterior cephalogram

RESUMEN Introducción: Universalmente se acepta que la radiografía postero-anterior de cráneo presenta menor grado de distorsión que otras imágenes radiográficas, por lo que las mediciones en ella son consideradas confiables. Objetivo: Determinar el porcentaje de distorsión que se presenta en las diferentes regiones faciales de la radiografía posteroanterior de cráneo. Métodos: Treinta cráneos humanos con sus mandíbulas fueron divididos por tres planos horizontales y cuatro verticales en quince cuadrantes; resultaron diez en el cráneo y cinco en la mandíbula. En cada uno de ellos se colocó un alambre de acero en posiciones vertical y horizontal y se midió su longitud (medida real). A cada conjunto se le tomó una radiografía en proyección postero-anterior y se midió la longitud de los alambres en la imagen (medida radiográfica). Resultados: No fue posible medir en los cuadrantes laterales del cráneo. La medida horizontal en los cuadrantes intermedios inferiores derecho e izquierdo del cráneo y en los cuadrantes intermedio y lateral de ambos lados de la mandíbula no es confiable; en el cuadrante mediano de la mandíbula se minimiza; en los cuadrantes medianos superior e inferior e intermedios superiores derecho e izquierdo del cráneo se magnifica. Las medidas verticales en todos los cuadrantes son confiables; en los cuadrantes intermedios superiores derecho e izquierdo del cráneo y en los intermedios y laterales derechos e izquierdos de la mandíbula se magnifica; en los cuadrantes intermedios inferiores y medianos superior e inferior del cráneo y mediano de la mandíbula se minimiza. La menor distorsión para ambas medidas se presenta en el cuadrante mediano superior del cráneo. Se reportan los porcentajes de distorsión para cada cuadrante. Conclusiones: Se presenta distorsión en la radiografía postero-anterior de cráneo y esta varía de una región a otra de la cara(AU)

ABSTRACT Introduction: Universally, it has been accepted that the postero-anterior cephalogram presents less distortion than any other x-ray radiograph; for this reason, the measurements taken on it are considered reliable. Objective: To determine for a postero-anterior cephalogram, what percentage of distortion is present in different regions of the skull and mandible. Methods: Thirty human skulls with their mandibles were divided by three horizontal and four vertical planes in fifteen quadrants, resulting ten in the skull and five in the mandible. In each quadrant, one vertical and one horizontal steel wire were fixed and their lengths were measured (real value). To each set, a postero-anterior cephalogram was taken and the wire images were measured (radiograph value). Results: No measurement could be taken in the lateral quadrants of the skull. The horizontal measurement in the right and left intermediate inferior quadrants of the skull and in the right and left intermediate and lateral quadrants of the mandible is not reliable; in the median quadrant of the mandible it is minimized; in the median superior and inferior and intermediate superior right and left quadrants of the skull it is magnified. The vertical measurement in all the quadrants is reliable; in the right and left intermediate superior quadrants of the skull and right and left intermediate and lateral quadrants of the mandible it is magnified; in the right and left intermediate inferior and median superior and inferior quadrants of the skull and median quadrant of the mandible it is minimized. The minimum distortion for both measurements is present in the median superior quadrant of the skull. The percentage of distortion in each quadrant for both measurements is reported. Conclusions: Distortion is present in the postero-anterior cephalogram and it varies from one region to another of the face(AU)

[Tooth and pregnancy, a public health issue]. / Dents et grossesse, un enjeu de santé publique.

Pregnancy is a particularly risky moment for periodontal and oral healthcare. The main diseases encountered are the development or worsening of carious lesions and gestational periodontal diseases such as gingivitis, epulis or gestational periodontitis. There is a lack of knowledge from health professionals and their patients, firstly on the link between poor oral hygiene and the impact on pregnancy, and secondly on the feasibility of oral care during pregnancy. There is a link between periodontal diseases and the increase of premature delivery risk, child with low birth weight and pre-eclampsia. Periodontal care during pregnancy would lower this risk. However, no link has been highlighted to date between oral care provided during pregnancy and the reduction of premature delivery or even of pre-eclampsia. Loco-regional anaesthesia and taking x-ray images-even dental panoramic radiography-are not contraindicated for pregnant women. All periodontal and oral care can be performed during pregnancy, at all gestational ages.

Dental X-Rays and the Risk of Thyroid Cancer and Meningioma: A Systematic Review and Meta-Analysis of Current Epidemiological Evidence.

Background: Exposure to moderate-to-high doses of ionizing radiation is the only established environmental risk factor for thyroid cancer and brain and central nervous system tumors. Considering the high lifetime prevalence and frequency of exposure to dental X-rays, the most common source of diagnostic radiation exposure in the general population, even a small associated increase in cancer risk would be of considerable public health importance. With the objective to inform clinical practice and guidelines, we synthesized the current epidemiological evidence on the association between dental X-rays and the risk of thyroid cancer, meningioma, and other cancers of the head and neck region. Methods: The Medline, Embase, and Web of Science databases were searched to identify eligible studies. Summary odds ratio/relative risk estimates and confidence intervals were extracted, and pooled risk ratios (RRs) for each cancer were calculated using random effects meta-analysis. Results: The literature search identified 5537 publications; of these, 26 studies including 10,868 cancer patients were included in the synthesis. The random effects meta-analyses, based on seven studies of thyroid cancer (six case/control, one cohort) and eight studies of meningioma (all case/control), showed that multiple (or repeated) exposures to dental X-rays were significantly associated with an increased risk of thyroid cancer (pooled RR = 1.87 [95% confidence interval, CI 1.11-3.15]) and meningioma (pooled RR = 1.53 [CI 1.26-1.85]). There was no association with glioma, and there were too few studies of other cancers of the head and neck region to conduct a meaningful meta-analysis. Conclusions: Based on a meta-analysis of retrospective case/control studies, these findings provide some support to the hypothesis that multiple (or repeated) exposures to dental X-rays may be associated with an increased risk of thyroid cancer and meningioma. These studies did not include individual organ doses and ages at exposure, and are subject to recall bias and other limitations. Furthermore, the thyroid exposure has decreased dramatically over time from the use of thyroid shields and improved technology/equipment. Prospective studies, based on dental X-ray records and patient follow-up, are needed to test the hypothesis further and clarify the possible cancer risk associated with dental radiography, as although the risk at the individual level, particularly with improved technology/equipment, is likely to be very low, the proportion of the population exposed is high. Considering that about one-third of the general population in developed countries is routinely exposed to one or more dental X-rays per year, these findings manifest the need to reduce diagnostic radiation exposure as much as possible.

Dental Cone Beam Computed Tomography in Children: Clinical Effectiveness and Cancer Risk due to Radiation Exposure.

Firstly used in the early 90s to generate 3-dimensional projections of X-ray images, cone beam computed tomography (CBCT) has resulted in a large application in dentomaxillofacial imaging, even in children. CBCT uses ionizing radiation that may cause damage to the DNA, and children are at the greatest carcinogenesis risk due to their higher tissue radiosensitivity and their longer life expectancy compared to adults. The questions of whether the cancer risk is really increased after repeated dental CBCT in childhood and of what the underlying biological basis is have become hot topics in the field of dentistry and radiobiology. We performed an overview of the current literature to assess an acceptable role of CBCT in pediatric dentistry.

Attitude and awareness of general population towards radiation hazards and safety: An institutional study.

CONTEXT: Radiological investigations play a pivotal role in the diagnosis and treatment of a wide range of procedures. AIM: To assess the knowledge regarding adverse consequences of radiological examination and encourage awareness regarding radiation protection amongst general public. SETTINGS AND DESIGN: A questionnaire-based cross-sectional study conducted amongst patients visiting the dental outpatient department. MATERIALS AND METHODS: 1,000 adult male and female patients within the age of 20-70 years who visited the outpatient department during May-July 2017 were included in the study. STATISTICAL ANALYSIS: Comparison of frequencies of responses to each item with age and gender was done using chi square test. For all statistical tests, P < 0.05 was considered to be statistically significant, keeping α error at 5% and ß error at 20%. RESULTS: 85.3% participants had visited a hospital earlier and 69.3% had undergone the procedure of an X-ray earlier. Out of those patients, only 24.7% of the participants had any knowledge about the equipment or the procedure while taking a radiograph. 5.2% of the participants were given any safety measures during the radiological procedure. 14.4% had knowledge of the risks and hazards associated with radiation. CONCLUSIONS: This short study showed that there is a need for educating the general population about the hazards and risks associated with radiation exposure.

Investigation of radiation-protection knowledge, attitudes, and practices of North Queensland dentists.

AIM: Queensland has current radiation-protection guidelines; however, with the absence of data exploring compliance and implementation, the efficacy is unknown. The aim of the present study was to investigate the knowledge and attitudes on radiation protection among private North Queensland (NQ) dentists. METHODS: A quantitative methodology was employed in an observational and descriptive study using questionnaires for data collection. RESULTS: Of the 154 questionnaires distributed, 63 were completed and returned. The respondents' knowledge concerning the technical details of their equipment was limited, with 31.5% and 47% not knowing the tube voltage and current utilized for their machines, respectively. In total, 23.8% of dentists had limited knowledge about the speed of the conventional film they used, 90.5% of respondents agreed that the role of imaging in dentistry is important, and 75.8% dentists reported the thyroid as the most important organ to protect during dental radiography. Their knowledge regarding position-distance rule was reasonably adequate; 80.3% of the dental practices appeared to follow the Australian Radiation Protection and Nuclear Safety Agency guidelines, 95.2% preferred taking radiographs if it was only urgent, and 69.8% identified a need for spreading awareness regarding radiation protection. CONCLUSIONS: An opportunity and need for further continuing education was identified among NQ dentists to ensure safety of patients.

Doses, Benefits, Safety, and Risks in Oral and Maxillofacial Diagnostic Imaging.

Diagnostic imaging is essential in dentistry. Doses range from low to very low, benefits to patients can be immense, and safe techniques are well known but widely ignored. Doses range from very low with properly executed intraoral, cephalometric, and panoramic imaging to higher than multidetector computed tomography with cone-beam computed tomography. Benefits are substantial: imaged dental disease, often obscured from direct vision by size and anatomy, can pose a mortal threat to the patient. Additionally, imaging is often central in planning complex dental procedures. Safe imaging in dental environments is straightforward; the means for minimizing dose and maximizing diagnostic efficacy have been widely and inexpensively available for decades. Such techniques reduce patient dose by some 80% over traditional techniques but are infrequently used. Digital panoramic equipment reduces doses markedly. For cone-beam computed tomography imaging, selection criteria are critical in defining appropriate fields of view and presets; several publications address this. It is treacherous to discuss risk in oral and maxillofacial radiology. There are more than 330 million dental x-ray examinations annually, the majority being intraoral examinations, with steady increases in panoramic and cone-beam computed tomography. Radiation carcinogenesis from conventional imaging is unlikely, while large field-of-view, high-resolution preset cone-beam computed tomography can be comparable in carcinogenesis risk to craniofacial multidetector computed tomography. Uncertainties in risk estimation from low doses coupled with the huge numbers of dental images taken annually and the rapid growth of cone-beam computed tomography dictate that safe oral and maxillofacial imaging is in the interests of patients, staff, and the public. As low as reasonably achievable (ALARA) practices and linear no-threshold risk modeling continue to be prudent and appropriate.

A comprehensive review of the literature on the biological effects from dental X-ray exposures.

PURPOSE: Routine dental X-rays are among the most common sources of ionizing radiation exposure for healthy individuals globally, with 300 examinations/1000 individuals/year as documented by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) global survey of medical radiation usage and exposure. Furthermore, in the United States of America, an increased use of dental radiography is evident. However, with the shift from using film to digital image receptors, the dose of radiation per routine examination has decreased. Despite this, there remains public concern of dental X-rays. This continuing concern highlights the need to review the literature on biological and health effects related to exposure, from dental X-rays. MATERIAL AND METHODS: This report presents studies investigating biological and health effects related to exposures using dental X-rays in patients and provides a critical evaluation. Relevant studies specific to dental X-rays are reviewed from 1970 and onward with the bulk data in this field resulting from epidemiological and biomonitoring studies. RESULTS: While, most epidemiological studies suggest a possible correlation between head/neck related tumors and exposure to dental X-rays, evidence for causation is lacking. Biomonitoring studies suggest that exposure to low-level radiation such as that of dental radiography may not be a factor in inducing long-term chromosomal damage, but may result in localized cytotoxicity in the irradiated region of the mouth, with no long-term harm. CONCLUSIONS: In general, the total number of studies is low and the majority of the data has been generated from poorly designed experiments. This review will highlight shortcomings that could influence outcomes and provide a more balanced interpretation that could impact the public perception and the level of public concern on the health effects resulting from dental X-rays.

Awareness Level of Radiation Protection among Dental Students.

INTRODUCTION: Dental radiographs have always been the mainstay of the diagnosis of oral diseases. Even if the radiation hazard posed by the dental radiographs is low but still accumulation of such low level radiation in human body over a time period can pose a threat to the overall health of the individual. The aim of this study is to assess the knowledge of dental students about radiation protection and hazards. METHODS: The present cross sectional study was conducted by enrolling one hundred 4th year dental students from the two teaching hospitals in Chitwan district of Nepal. A questionnaire consisting of a total of 20 questions was distributed and each question was allocated 0.5 marks for correct response whereas no deduction for wrong answer. RESULTS: The results of the present study depicted that 85 (85%) of the total students enrolled in the study had "good" knowledge about the radiation physics, protection and hazards whereas only 15 (15%) of them had "poor" knowledge. CONCLUSIONS: The study concluded that teachers should involve in imparting more and more knowledge as well as training about the topic and dental curriculum should be altered so as to train the budding dentists about all aspects of radiation.

Procedural pain in routine dental care for children: a part of the Swedish BITA study.

AIM: To investigate the frequency and reported intensity levels of dental treatment pain and discomfort in children, in conjunction with regular dental visits. METHODS: The study included 2363 children in four different age cohorts. Data was collected from structured interviews by dental personnel regarding pain experiences or discomfort after treatments, including analgesia, extractions, operative treatments and radiographic examinations. RESULTS: One-third of all treatment occasions were experienced as painful and/or causing discomfort. Treatment sessions including analgesia were assessed as painful in 49.7% of occasions, with injection being the most common given reason for pain. Extraction was painful in 62.4% of occasions, with injection as the main reason for pain. Operative treatments were assessed as painful in 38.8% of occasions, with drilling as the most common reason for pain and discomfort. Pain was reported in approximately 19% of all radiographic examinations. CONCLUSIONS: Injection was the major reason for pain during treatment, including injection and extraction, while drilling was the most common cause of pain during restorative treatment. Dentists should try to minimise the experience of pain and discomfort by using all available measures to perform pain-free and effective dental injections.

Estimated radiation risk of cancer from dental cone-beam computed tomography imaging in orthodontics patients.

BACKGROUND: Radiation dose evaluation is important to cone-beam computed tomography (CBCT) for routine orthodontic treatment planning, especially for a significant proportion of children in orthodontic patients. This study evaluated the patient radiation dose and estimated the radiation cancer risk on dental CBCT according to the calculations by the Monte Carlo simulation method. METHODS: The dental CBCT scanner evaluated in this project was the i- CAT® (Imaging Sciences International Inc., PA, U.S.A.) device. Organ doses and effective doses were calculated by using personal computer-based Monte Carlo simulation (PCXMC 2.0 Rotation) software. The cancer risk resulting from the exposure to ionizing radiation was estimated by using the BEIR VII (Biologic Effects of Ionizing Radiation VII) report model, and the risk of exposure-induced death (REID) was assessed by PCXMC 2.0 Rotation software. RESULTS: The largest contribution to the organ dose and effective dose at Zref 83 cm positioned in the dental CBCT x-ray beam centerline was from the salivary glands (738.29µGy, 7.38 µSv). The different organ doses showed the maximum values at the different Zref locations, and the largest contribution to the organ dose and effective dose of all simulated positions was from the thyroid (928.77µGy, 37.5 µSv). The REID values in the 10-year olds (22.6 × 10- 7, female; 19 × 10- 7, male) were approximately double than those in 30-year olds (10.4 × 10- 7, female; 8.88 × 10- 7, male) for all cancers. The highest change during age range from 10 to 30 was shown in breast cancer of females. CONCLUSIONS: Although individual cancer risk estimates as a function of gender and age are small, the concern about the risks from dental CBCT is related to the rapid increase in its use for orthodontic practice, especially in children patients.

Cone Beam Computed Tomography.

In the last several decades, the need for 3D images in dentistry have developed. Computerized tomography was first introduced mainly with the advent of implantology, but its use remained limited to a small number of specialists, due to its indications, access and dose radiation. In the late 90's, a new technology using a cone-shaped beam and a reciprocating detector, which rotates around the patient 360 degrees and acquires projected data in a single rotation, namely the cone beam computerized tomography (CBCT), invaded dentistry, making the perception of 3D easily acceptable to dentists and their patients.

Clinical considerations and potential liability associated with the use of ionizing radiation in orthodontics.

Ionizing radiation is a known carcinogen. Its damaging effects can be deterministic or stochastic. Deterministic effects occur only after radiation exposure thresholds are reached, but stochastic effects are random, and there is no known threshold below which harmful effects will not occur. Therefore, the use of ionizing radiation in orthodontic treatment should bring a benefit to the patient that outweighs the risks. No legally binding statutes, rules, or regulations provide explicit radiographic prescription protocols for orthodontic practice. The objective of this article was to discuss guidelines and risk management strategies for appropriate and defensible use of ionizing radiation in orthodontics. Guidelines are discussed for radiographic acquisition at different points along the orthodontic treatment timeline. In addition, risk management strategies and best practices are presented regarding adequate and defensible radiographic interpretation. These guidelines are not rigid and do not establish standards of care; they should be modified as necessary for each patient and each clinical encounter.

Understanding and communicating radiation dose and risk from cone beam computed tomography in dentistry.

With the increased use of 3-dimensional dental imaging and cone beam computed tomography in dentistry, dental practitioners should understand and effectively communicate the associated radiation doses and risks to patients. This article will explain dose and risk of cone beam computed tomography technology, drawing on 3 decades of experience in communicating human health risk to the public from radiation exposure in the environment. This report provides examples of dose and risk metrics and comparisons to help providers understand the risk to their patients and to effectively communicate that risk. In the clinical setting, providers can use the guidelines outlined in this report for responsible delivery of dose using cone beam computed tomography. In addition, the metrics and comparisons provided here can be shared with patients to aid in communicating pertinent information about dose and risk.

Buccal mucosa cell damage in individuals following dental X-ray examinations.

The aim of the present study was to monitor genotoxic and cytotoxic effect of X-ray on exfoliated buccal mucosa cells and investigate the association between the effects and the accumulated absorbed doses of oral mucosa. 98 participants' buccal mucosa cells were collected before and 10 days after different series of dental radiographs performed. Cytological preparations were successively dyed with the methods of Feulgen and fast-green, and analyzed under a light microscope. Micronuclei (MN)and other cells were scored. Accumulated absorbed dose of buccal mucosa was estimated with the method of anthropomorphic phantom and dosimeter chips. The dose rang was 0.18-3.54 mGy. A significant difference in the rate of MN cell was found before and after X-ray examinations (P = 0.008) as well as in the rates of Pyknotic (p < 0.001) and Karyolytic cell (p = 0.0021). When only the patients whose mucosa absorbed dose is lower than 1 mGy was analyzed, significant differences were not found except for Karyolytic cells (p = 0.0313). There was a correlation between the accumulated does and the change rate (ρ = 0.25, p = 0.0118). The frequency of micronuclei cells in buccal mucosa may be increased when a series of dental radiographs including a CBCT examination was performed.