Is it possible to predict neurosensory alterations in impacted lower third molar removal based on preoperative imaging procedures? A prospective cohort study.

BACKGROUND: Surgical extraction of the lower third molar (LTM) may trigger neurosensory injury of the inferior alveolar nerve, making extraction a real challenge. This study set out to assess whether is it possible to predict neurosensory alterations from preoperative imaging. MATERIAL AND METHODS: A total of 99 patients underwent 124 impacted lower third molar (ILTM) surgeries. Prior to surgery, panoramic and CBCT images were evaluated in an attempt to predict a neurosensory disturbance. Preoperative data (ILTM position, panoramic radiograph signs, inferior alveolar nerve (IAN) location and its contact with the ILTM roots) and intra/postoperative findings (extraction difficulty and sensitivity alterations) were recorded. Descriptive and bivariate data analysis was performed. Statistical comparison applied the chi-square test, Fisher test, and one-way ANOVA test. Statistical significance was established with a confidence interval (CI) of 95%. RESULTS: In 4.03% of cases, patients experienced neurosensory alterations. Of 124 ILTM positions in panoramic radiographs, 76 cases were considered to exhibit a potential neurosensory risk as they presented two or more types of superimposed relationships between ILTM and mandibular canal. Of these, alterations were reported in only three cases (3.95%). Of the 48 remaining ILTM images presenting only one sign, neurosensory alterations were observed in two cases (4.17%). No permanent alterations were recorded in any of the five cases observed. CONCLUSIONS: Within the limitations of the present study, prediction of neurosensory alterations prior to ILTM extraction by means of preoperative imaging did not show a significant statistical correlation with post-surgical incidence. Nevertheless, interruption of the canal´s white line (ICWL) or a diversion of the canal (DC) may predict an increased risk of IAN injury.

Carotid Artery Stenosis on Panoramic Radiographs and CT Scans in Patients With Malignancies After Radiotherapy.

BACKGROUND/AIM: This study aimed to identify the progression of carotid artery stenosis (CAS) in patients with head and neck cancer following radiation therapy (RT) by characterizing associated risk factors. PATIENTS AND METHODS: Panoramic radiographs (OPG), computed tomography (CT) scans, cone-beam CT (CBCT) scans, and ultrasonography (US) of 69 patients with head and neck tumors were selected and analyzed to identify the presence of CAS. Data on tumor location, smoking status, hypertension (HTN), hyperlipidemia (HLD), diabetes mellitus (DM), and treatment were collected from the patients' medical records. Patients who received chemotherapy or no treatment were excluded from the study. The differential diagnosis of other radiopacities and anatomical landmarks were excluded. Patients were divided into two groups: those with CAS (group1) and those without CAS (group 2) and their clinical information was compared. RESULTS: The overall prevalence of CAS on the panoramic radiographs was 16%. Of the 69 patients, 44 underwent radiography before and after radiotherapy, only seven had mild CAS on radiographs after radiotherapy, and no significant difference in CAS was identified before and after radiotherapy. There were also no differences between the groups regarding age, sex, smoking, hypertension, diabetes mellitus, hyperlipidemia, tumor location, and RT dose before and after radiation (p>0.05). CONCLUSION: Radiotherapy does not seem to affect the prevalence of CAS, although it has been identified in some patients after radiotherapy completion.

Does Panoramic X-ray Induce Cytogenetic Damage to Oral Cells? A Systematic Review With Meta-analysis.

AIM: The aim of this review was to evaluate the scientific literature regarding the cytogenetic damage in oral exfoliated cells of adult patients submitted to panoramic X-ray. MATERIALS AND METHODS: An extensive search of the literature was conducted on PubMed, Scopus and Web of Science databases for all studies published until April 2021 using combinations of the following keywords: "panoramic X-ray," "DNA damage," "genetic damage", "genotoxicity", "mutagenicity", cytotoxicity", "buccal cells", "oral mucosa", "tongue", "gingiva", "micronucleus assay", according to the PRISMA guidelines. All clinical studies in English language were included in the study. A total of 10 studies were identified. RESULTS: As expected, the results regarding the cytogenetic damage induced by panoramic X-ray are conflicting. Some authors have demonstrated that panoramic X-ray induces mutagenesis in oral cells, whereas others did not. After reviewing the 10 studies, two were classified as strong, four were considered moderate, and four were considered weak, according to the quality assessment components of the Effective Public Health Practice Project (EPHPP). Meta-analysis data revealed a negative response related to mutagenicity in oral cells by panoramic X-ray. CONCLUSION: Taken together, this review failed to demonstrate the association between micronucleus frequency and panoramic X-ray.

Evaluation of cell and DNA damage induced by panoramic radiography.

BACKGROUND: X-rays are potential mutagenic agents that can cause both the gene mutations and chromosomal aberrations. AIMS: In this study, the micronucleus (MN) test and the comet assay methods are implemented in order to observe the damage that can occur in the cell nucleus and in the structure of DNA of the patients who underwent a panoramic examination. METHODS AND MATERIALS: In our study, buccal mucosa swabs were obtained just before the radiography and 2 weeks after the radiography from 30 volunteer patients who had to take radiographs due to dental diagnosis. Changes in the nuclei of 1,000 cells of each swab sample had been counted under a light microscope and recorded. Besides, 100 cells of each other swab samples were analyzed by the comet assay. Comet assay parameters namely tail length and percentage of DNA in tail, which indicate the level of DNA damage were analyzed and compared in both groups. Statistical analysis was performed by using the Statistical Package for the Social Sciences (Version 21). RESULTS: In our study, the results of percentage of DNA in tail and tail length before and after X-ray exposure were statistically significant (P < 0.001). Likewise, increase in the MN frequency observed in buccal mucosa cells after X-ray exposure was found significant (P < 0.001). CONCLUSIONS: As a result, panoramic radiographs taken during dental diagnosis and treatment cause cytotoxicity and DNA damage in oral mucosal cells. Panoramic radiographs should be applied only when necessary, using an accurate radiographic technique and radioprotection criteria.

The panoramic dental radiograph for emergency physicians.

Dental emergencies are common reasons for presenting to hospital emergency departments. Here, we discuss the panoramic radiograph (orthopantomogram (OPG, OPT) as a diagnostic tool for the assessment of mandibular trauma and odontogenic infections. In this article, we review the radiographic principles of image acquisition, and how to conduct a systematic interpretation of represented maxillofacial anatomy. The aim is to equip the emergency physician with the skills to use the OPG radiograph when available, and to rapidly assess the image to expedite patient management. Included is a discussion of a number of cases seen in the emergency setting and some common errors in diagnosis.

Medication-Related Osteonecrosis of the Jaws: Two Center Retrospective Cohort Studies.

This retrospective cohort study aims to describe characteristics of patients with MRONJ, to identify factors associated with MRONJ development, and to examine variables associated with favourable outcome. Totally 32 patients were followed and observed: 21 females and 11 males, in the age range 35-84 in the period from 2009 to 2018. Clinical, radiological examination (Orthopantomograph and CBCT) and biopsy were performed in order to achieve diagnosis. Demographic and clinical variables were taken into consideration: sex, age, primary disease, medication type, mode of delivery, anatomic location, drug treatment duration, timing of tooth extraction, chemotherapy, presence of bone metastasis, aetiology of MRONJ, disease stage, and treatment modality. MRONJ developed under osteoporosis and malignant disease in 11 and 21 patients, respectively. MRONJ development was triggered by tooth extraction or trauma in 30 out of 32 cases, whereas the two patients developed MRONJ spontaneously. Stages I, II, and III were confirmed in 5 (16%), 18 (58%), and 9 (28%) patients, respectively. Mandible was affected in 23 (72%) patients. MRONJ was treated in our department by conservative and surgical modality. In this study we found that 65% of all patients were classified in the cured/improvement group and 35% in the stable/progression group. The female gender, osteoporosis as primary disease, oral regime intake, shorter period on BPs, earlier stage of disease, and specific anatomic localisation (frontal and premolar maxilla) were factors associated with better response to therapy and favourable clinical outcome. Comprehensive treatment protocol and further randomized studies are necessary for further improvements.

Doses in eye lens, thyroid, salivary glands, mammary glands, and gonads, due to radiation scattered in dental orthopantomography.

In the aim to support treatments and diagnostics in Dentistry the most common radiographies are the periapical radiography and the dental panoramic. In the dental panoramic the X-ray beam is addressed into a large zone of the face obtaining the image of the upper and lower jaw. In this procedure part of the X-rays are scattered reaching some other parts of the patient body. In this work the absorbed dose in the eye lens, thyroid, salivary glands, mammary glands, and gonads, was measured in patients undergoing a dental orthopantomography. Measurements were carried out with thermolmuminiscent dosimeters. With the absorbed doses the Effective dose were calculated. The highest dose was obtained in the salivary glands (30.4 µSv) and the lowest dose was obtained in thyroid (3.8 µSv).

Correlação entre a mineralização dos terceiros molares e a idade cronológica por três métodos / Correlación entre la mineralización del tercer molar y la edad cronológica por tres métodos / Correlation between third molar mineralization and chronological age by three methods

Introdução: os estágios de mineralização dentária têm sido utilizados em diversos estudos para a estimativa de idade, apresentando confiabilidade nos resultados. Objetivo: correlacionar a mineralização dos terceiros molares e a idade cronológica pelos métodos de Nolla, Demirjian e Nicodemo, Moraes e Médici Filho numa amostra populacional do nordeste brasileiro. Métodos: de um universo de 1 205 radiografias panorâmicas digitais, foram selecionadas 297 imagens de pacientes atendidos rotineiramente em um serviço de Radiologia Odontológica privado. Todas as imagens foram avaliadas em ambiente escurecido por três examinadores calibrados, utilizando as classificações de Nolla (1960), Demirjian (1973) e Nicodemo, Moraes e Médici Filho (1974). Os dados numéricos foram resumidos através das estatísticas descritivas de locação e dispersão. Para análise estatística foi ajustado um modelo de regressão linear simples considerando a idade como variável resposta. Para os testes, foi adotado o nível de significância de 5 porcento ciento. Resultados: o desenvolvimento dos terceiros molares foi mais adiantado no sexo masculino na maioria dos estágios, para os três métodos. Nos dentes superiores, o dimorfismo sexual foi mais evidente no estágio 7 de Nolla (diferença de 16,34 m no dente 18 e 14,43 m no dente 28). Nos dentes inferiores, as maiores diferenças ocorreram: no estágio 6 de Nolla (diferença de 13,92 m no 38 e 10,46 m no 48) e estágio 5 de Nicodemo (diferença de 16,23 m mais elevado no elemento 38 e 9,9 m no 48). O desenvolvimento dos dentes terceiros molares dos lados direito e esquerdo apresentou-se semelhante, contudo os dentes superiores apresentaram-se mais adiantados que os inferiores. O presente estudo permitiu o desenvolvimento de fórmulas baseadas em regressões lineares simples utilizando os três métodos propostos, possibilitando, assim, estimar a idade cronológica dos indivíduos da amostra. Conclusão: houve correlação do desenvolvimento dentário dos terceiros molares com a idade cronológica pelos três métodos(AU)

Introducción: las etapas de mineralización de los dientes se han utilizado en varios estudios para estimar la edad, lo cual ha mostrado resultados fiables. Objetivo: correlacionar la mineralización de los terceros molares y la edad cronológica por los métodos de Nolla, Demirjian y Nicodemo, Moraes y Medici Filho en una muestra de población del nordeste de Brasil. Métodos: a partir de un universo de 1 205 radiografías panorámicas digitales, se seleccionaron 297 imágenes de pacientes tratados de forma rutinaria en un servicio de radiología dental privada. Todas las imágenes fueron evaluadas en cuarto oscuro por tres examinadores calibrados, utilizando los métodos de Nolla (1960), Demirjian (1973) y Nicodemo, Moraes y Medici Filho (1974). Los datos numéricos se resumieron utilizando estadística descriptiva del contrato de arrendamiento y la dispersión. El análisis estadístico se ajustó un simple modelo de regresión lineal, considerando la edad como variable de respuesta. Para las pruebas, se adoptó el nivel de significación del 5 pr ciento. Resultados: el desarrollo de los terceros molares fue más temprano en los varones en la mayoría de las etapas, por los tres métodos. En los dientes superiores, el dimorfismo sexual fue más evidente en la etapa 7 de Nolla (diferencia de 16,34 m en el diente 18 y 14,43 m en el diente 28). En los dientes inferiores, las mayores diferencias ocurrieron: en la etapa 6 de Nolla (diferencia de 13,92 m no 38 y 10,46 m no 48) y etapa 5 de Nicodemo (diferencia de 16,23 m más elevado en el elemento 38 y 9,9 m no 48). El desarrollo de los dientes terceros molares de los lados derecho e izquierdo se presentó semejante, sin embargo los dientes superiores se presentaron más adelantados que los inferiores. Este estudio permitieron el desarrollo de formulaciones a base de regresiones lineales usando los tres métodos propuestos, permitiendo estimar la edad cronológica de los individuos en la muestra. Conclusiones: se observa una correlación de desarrollo de los dientes terceros molares con la edad cronológica por tres métodos(AU)

Introduction: dental mineralization stages have been used in several studies to estimate age, and the results obtained have been found to be reliable. Objective: correlate third molar mineralization and chronological age using the methods developed by Nolla, Demirjian, and Nicodemo, Moraes and Medici Filho in a population sample from Northeast Brazil. Methods: of a total 1 205 digital panoramic radiographs, 297 were selected of patients routinely seen in a private dental radiology service. All the images underwent darkroom evaluation by three qualified examiners using the methods developed by Nolla (1960), Demirjian (1973), and Nicodemo, Moraes and Medici Filho (1974). Numerical data were summarized by location and dispersion descriptive statistics. For statistical analysis a simple linear regression model was adjusted which considered age as response variable. A significance level of 5 percent was adopted for the tests. Results: third molar development occurred earlier in males in most stages by the three methods. In upper teeth, sexual dimorphism was more evident in Nolla stage 7 (difference of 16.34 m in tooth 18 and 14.43 m in tooth 28). In lower teeth, the greatest differences occurred in Nolla stage 6 (difference of 13.92 m in 38 and 10.46 m in 48) and Nicodemo stage 5 (difference of 16.23 m higher in tooth 38 and 9.9 m in 48). Third molar development was similar on the right and left sides, but greater in upper teeth than in lower teeth. The study allowed development of linear regression formulas based on the three methods proposed, making it possible to estimate the chronological age of the individuals in the sample. Conclusions: the three methods found a correlation between third molar development and chronological age(AU)

GENOTOXICITY AND CYTOTOXICITY OF X-RAYS IN CHILDREN EXPOSED TO PANORAMIC RADIOGRAPHY. / GENOTOXICIDADE E CITOTOXICIDADE DOS RAIOS X EM CRIANÇAS SUBMETIDAS À RADIOGRAFIA PANORÂMICA.

OBJECTIVE: To assess the genotoxicity and cytotoxicity produced by X-rays in the epithelium of the oral mucosa of infants exposed to panoramic radiography. METHODS: The sample consisted of 30 healthy children, 19 females and 11 males, ranging in age from 4 to 10 years (average of 7 years of age). Oral mucosa cells were collected by liquid-based cytology immediately before and after seven days following the exposure to panoramic radiography. Smears were processed and stained using the modified Feulgen Rossenbeck technique. Bud and broken egg nuclear projections, changes in the form of micronuclei, and genotoxic and cytotoxic changes of pyknosis, karyorrhexis and karyolysis were analyzed and quantified. RESULTS: The frequency of pyknosis, buds and broken eggs was significantly higher after exposure to X-rays (p<0.05), but there was no statistically significant difference regarding gender, as well as in the other changes studied. CONCLUSIONS: Exposure to X-rays emitted during submission to panoramic radiography may induce cell death in the epithelium of children's oral mucosa. No evidence was found for a significant genotoxic effect.

OBJETIVO: Analisar a genotoxicidade e a citotoxicidade produzidas por raios X no epitélio da mucosa oral de crianças durante a obtenção da radiografia panorâmica. MÉTODOS: A amostra foi constituída por 30 crianças saudáveis, sendo 19 do sexo feminino e 11 do masculino, com faixa etária de 4 a 10 anos (média de 7 anos de idade). As células epiteliais da mucosa oral foram coletadas por meio de citologia esfoliativa em base líquida imediatamente antes e após sete dias da obtenção da radiografia panorâmica. Os esfregaços foram processados e corados utilizando a técnica de Feulgen Rossenbeck modificada. Foram analisadas e quantificadas projeções nucleares dos tipos bud e broken egg, alterações genotóxicas na forma de micronúcleo e alterações citotóxicas dos tipos picnose, cariólise e cariorrexe. RESULTADOS: A frequência de picnose, bud e broken egg foi significativamente maior após a exposição aos raios X (p<0,05), porém não houve diferença estatisticamente significante em relação ao sexo, bem como nas demais alterações estudadas. CONCLUSÕES: A exposição aos raios X emitidos durante a obtenção da radiografia panorâmica pode induzir à morte celular no epitélio da mucosa oral de crianças. Não foi encontrado indício significativo de efeito genotóxico.

Genotoxicidade e citotoxicidade dos raios x em crianças submetidas à radiografia panorâmica / Genotoxicity and cytotoxicity of x-rays in children exposed to panoramic radiography

RESUMO Objetivo: Analisar a genotoxicidade e a citotoxicidade produzidas por raios X no epitélio da mucosa oral de crianças durante a obtenção da radiografia panorâmica. Métodos: A amostra foi constituída por 30 crianças saudáveis, sendo 19 do sexo feminino e 11 do masculino, com faixa etária de 4 a 10 anos (média de 7 anos de idade). As células epiteliais da mucosa oral foram coletadas por meio de citologia esfoliativa em base líquida imediatamente antes e após sete dias da obtenção da radiografia panorâmica. Os esfregaços foram processados e corados utilizando a técnica de Feulgen Rossenbeck modificada. Foram analisadas e quantificadas projeções nucleares dos tipos bud e broken egg, alterações genotóxicas na forma de micronúcleo e alterações citotóxicas dos tipos picnose, cariólise e cariorrexe. Resultados: A frequência de picnose, bud e broken egg foi significativamente maior após a exposição aos raios X (p<0,05), porém não houve diferença estatisticamente significante em relação ao sexo, bem como nas demais alterações estudadas. Conclusões: A exposição aos raios X emitidos durante a obtenção da radiografia panorâmica pode induzir à morte celular no epitélio da mucosa oral de crianças. Não foi encontrado indício significativo de efeito genotóxico.

ABSTRACT Objective: To assess the genotoxicity and cytotoxicity produced by X-rays in the epithelium of the oral mucosa of infants exposed to panoramic radiography. Methods: The sample consisted of 30 healthy children, 19 females and 11 males, ranging in age from 4 to 10 years (average of 7 years of age). Oral mucosa cells were collected by liquid-based cytology immediately before and after seven days following the exposure to panoramic radiography. Smears were processed and stained using the modified Feulgen Rossenbeck technique. Bud and broken egg nuclear projections, changes in the form of micronuclei, and genotoxic and cytotoxic changes of pyknosis, karyorrhexis and karyolysis were analyzed and quantified. Results: The frequency of pyknosis, buds and broken eggs was significantly higher after exposure to X-rays (p<0.05), but there was no statistically significant difference regarding gender, as well as in the other changes studied. Conclusions: Exposure to X-rays emitted during submission to panoramic radiography may induce cell death in the epithelium of children's oral mucosa. No evidence was found for a significant genotoxic effect.

Dental Anomalies as Late Adverse Effect among Young Children Treated for Cancer.

PURPOSE: The aim of this study was to compare the incidence of dental complications in childhood cancer survivors with that of healthy control subjects, and to determine the possible influence of various factors associated with patient and treatment. MATERIALS AND METHODS: Sixty-one panoramic radiographs of the dentition of cancer survivors were compared with 521 radiographs of healthy patients at a similar age, between 5 and 18 years. The mean period from termination of therapy was 4.9 years (58.9 ± 34.3 months), and 51 children (83.60%) were under age 5 when therapy began. RESULTS: Dental anomalies were found in 38 cancer survivors (62.29%) and 69 control subjects (13.24%) (p < 0.001). Agenesis of teeth was found in 19 cancer patients (31.14%) and in 48 control subjects (9.21%). Microdontic teeth were found in 22 cancer survivors (36.06%) and 15 control subjects (2.87%) (p < 0.001), whereas teeth with short roots were found in seven cancer patients (11.47%) and 15 control subjects (2.87%) (p < 0.01). Dental anomalies in cancer patients were more common in some tooth groups and were not observed in others. The frequency of dental anomalies did not show correlation with age at the beginning or termination or time of therapy. CONCLUSION: Children under the age of 5 are in a high risk group for dental complications after anticancer treatment. Rudimentary chemotherapy has a considerable impact on the occurrence of dental anomalies.

Panoral dose assessment: a comparative report of methodologies.

National guidance from the Institute of Physics and Engineering in Medicine (IPEM Report 91) currently recommends that the patient dose for a panoral X-ray unit is measured as dose area product (DAP) replacing dose width product described in earlier guidance. An investigation identifying different methods available to carry out this measurement has been undertaken and errors in the methodologies analysed. It has been shown that there may be up to a 30 % variation in DAP measurement between methods. This paper recommends that where possible a DAP meter is used to measure the dose-area product from a panoral X-ray unit to give a direct DAP measurement. However, by using a solid-state dose measurement and film/ruler to calculate DAP the authors have established a conversion factor of 1.4. It is strongly recommended that wherever a DAP value is quoted the methodology used to obtain that value is also reported.

Genotoxicity of digital panoramic radiography on oral epithelial tissues.

OBJECTIVE: To evaluate the genotoxic effects of x-rays on gingival and buccal epithelial cells during panoramic dental radiography using the micronucleus test. METHOD AND MATERIALS: Eighty otherwise healthy subjects who required a diagnostic panoramic radiograph and met the selection criteria were included in the study. Epithelial cells were obtained from the maxillary anterior gingiva and buccal mucosa by gentle scraping with a wooden spatula immediately before exposure and again 10 days after exposure. Cytologic preparations were made according to the Papanicolaou staining method and analyzed under a light microscope for micronucleus count. RESULTS: The mean ± SD micronucleus count of gingival epithelial cells was 1.08 ± 0.76 before radiographic exposure and 1.6 ± 0.93 after exposure. This increase was statistically significant (P < .05). Similarly, there was an increase in the postexposure micronucleus count in the buccal mucosa, but this increase was not significant (P > .05). A significant correlation was observed between the age of subjects and micronucleus count, although no such correlation was found between sex and micronucleus count. CONCLUSION: Although radiation-related effects from panoramic radiography were reduced compared with full-mouth intraoral periapical radiographs or radiotherapy, the results of this study show that genotoxic effects do take place. Thus, radiographs should be taken with adequate protection measures and only when the potential benefit outweighs the potential risk.

Indicadores de maduración esquelética y dental en pacientes de ortodoncia con menarquía / Indicators of skeletal and dental maturation in orthodontics patients presenting menarche

El propósito del presente trabajo fue determinar según la menarquía: la edad ósea, los estadios de maduración esquelética, los estadios de maduración de las vértebras cervicales y los estadios de calcificación del canino y el segundo premolar mandibulares izquierdos. Se realizó un estudio transversal y descriptivo en 30 pacientes femeninas con menarquía que ingresaron en la Clínica de Ortodoncia de la Facultad de Estomatología de La Habana, en el periodo comprendido entre abril de 2004 y septiembre de 2006. A cada paciente se le realizó una telerradiografía lateral de cráneo, una radiografía de la mano izquierda y una radiografía panorámica o periapical de la hemiarcada mandibular izquierda. En cada caso se evaluaron los métodos Taner-Whitehouse 2 (TW2), Grave y Brown, Hassel y Farman y Demirjian. Se estudiaron las variables: edad de aparición de la menarquía, edad ósea, edad cronológica, estadios de maduración esquelética, estadios de maduración de las vértebras cervicales, estadios de calcificación del canino y el segundo premolar mandibulares izquierdos. El promedio de la edad de aparición de la menarquía en esta muestra fue de 12,00 años con una desviación estándar de 1,00 año. Los promedios de la edad ósea fueron superiores a los de la edad cronológica en todos los grupos de edades. Las 30 pacientes estudiadas se encontraban en: estadios de maduración esquelética mayores que 4, estadios de maduración de las vértebras cervicales mayores que 1, estadio H de calcificación del canino mandibular izquierdo y estadios superiores al E para el segundo premolar mandibular izquierdo. En todos los métodos determinados se encontró que la mayoría de las pacientes con menarquía estaban en los estadios de maduración más avanzados(AU)

The aim of present paper was to determine according menarche the bone age, skeletal maturation stages, maturation stage of cervical vertebrae and the stages of calcification of canine and the second left mandibular premolars. A descriptive and cross-sectional study was conducted in 30 female patients with menarche admitted in the Orthodontics Clinic of the Stomatology Faculty of La Habana from April, 2004 to September, 2006. Each patient undergoes a lateral teleradiography of skull, radiography of the left hand and a panoramic of periapical radiography of the left mandibular hemiarcade. In each case the Taner-Whitehouse 2 (TW2), Grave and Brown, Hassel and Farman and Demirjian methods were assessed. Following variables were studied: age at menarche appearance, bone age, chronologic age, skeletal maturation stages, the maturation stages of cervical vertebrae, calcification stages of the canine and the second left mandibular premolar. The age mean of the menarche's appearance in our sample was of 12,00 years with a SD of 1,00 year. Means of bone age were higher than those of chronologic age in all age groups. The 30 study patients were in skeletal maturation stages higher then 4, in maturation stages of cervical vertebrae higher than 1, in H stage of calcification of left mandibular canine and in stages higher than E for the second left mandibular premolar. In all determined methods most of patients with menarche were in more advances maturation stages(AU)

Absorbed radiation doses during tomographic examinations in dental implant planning: a study in humans.

OBJECTIVE: The aim of this human study was to evaluate the radiation doses in the buccal cavity and face, during panoramic, spiral conventional tomography, and helicoidal computerized tomography exams. MATERIAL AND METHODS: Lithium fluoride TL detectors (TLD-100) were placed on the skin at anatomic points such as parotid glands, submandibular glands, thyroid glands, and crystalline to assess the skin entrance dose in 19 patients who were to undergo dental implant surgery. RESULTS: In the panoramic exam, maximum doses were observed near the parotid glands at 1.57 (±18%) mGy on the right and 1.89 (±18%) mGy on the left. In the spiral conventional tomography exam, the maximum dose was 4.41 (±21%) mGy near the right and left parotid glands, whereas near the right or left submandibular glands, the maximum doses reached 40.7 (±18%) mGy. In the helicoidal computerized tomography for mandibular and maxilla exams, the maximum dose was 40.9 (±15%) mGy near the parotid glands and 41.0 (±18%) mGy near the submandibular glands. Near the thyroid and eye lens, doses were lower than 0.23 (±21%) in all exams. CONCLUSION: Regardless of the exam target area, the submandibular and parotid glands represented the most irradiated organs. This data suggests that efforts should be made by professionals to improve and optimize methods in order to reduce doses without losing the information necessary for treatment planning.

Radiation exposure to critical organs in panoramic dental examination.

Nowadays, radiography is a necessary procedure in diagnosis and treatment of patients with dental problems. According to the ALARA (as low as reasonably achievable) principle, dentists must take radiographs of sufficient quality at the lowest possible radiation dose to the patients. The assessment of patient dose on panoramic radiography is difficult because of dynamic nature of the imaging process and the narrow width of the x-ray beam. The present work describes an experiment undertaken using thermoluminescence dosimeters (TLD-100) to obtain the absorbed dose in organs and sensitive tissues in head and neck region during panoramic radiography, based on patient measurement. The overall mean entrance surface dose on thyroid, right and left lens of eyes, parotid glands (right and left) and occipital region in panoramic were 38, negligible, negligible, 367, 319 and 262 µGy, respectively. The results show that there are differences between patient doses examined by different panoramic systems. There is a tendency for lower organ doses for digital compared with analogue panoramic units.

Patient dosimetry and a novel approach to establishing Diagnostic Reference Levels in dental radiology.

Diagnostic Reference Levels provide a method of ensuring that patient doses in medical procedures are kept at acceptable levels. Their application in dentistry can provide an indication of current dose levels and can assist in potentially significant dose reduction in Ireland given the number of patients screened annually. This study involved retrospective analyses of entrance surface dose and dose-width-product measurements obtained in Irish Dental Practices for both Intra-Oral and Panoramic units respectively, followed by comparisons with Monte-Carlo generated computer models of these procedures. Analysis was performed on data from 33 Intra-Oral units for an Adult Mandibular Molar entrance surface dose, 198 readings for a proposed mGy/mAs reference level and 50 Panoramic machines for a dose-width product investigation. The third quartile value of the entrance surface dose for a standard Adult Mandibular Molar Intra-Oral radiograph is (2.40 ± 0.92)mGy, compared to a computer-modelled value of 2.60 mGy. The third quartile mGy/mAs value for Intra-Oral procedures is (1.03 ± 0.38)mGy/mAs, compared to a computer-modelled value of 0.75 mGy/mAs. The third quartile dose width product for an Adult Panoramic radiograph is (59.89 ± 20.97)mGymm, compared to a computer-modeled value of 62.40 mGymm. It is proposed to introduce Diagnostic Reference Levels of 2.4 mGy for an Adult Mandibular Molar Intra-Oral radiograph and 60 mGymm for an Adult Panoramic radiograph. The use of a new reference quantity in Intra-Oral radiology is also suggested. This has a value of 1 mGy/mAs and may be introduced alongside established procedures. These levels can be taken as guides to acceptable doses, but it should be noted that further reductions are practical under ALARA principles.

Analysis of micronuclei in buccal epithelial cells in patients subjected to panoramic radiography.

CONTEXT: Ionizing radiation is a well-known carcinogen in humans. Chromosomal aberrations and formation of micronuclei in cell cytoplasm are early biological evidence of carcinogenesis. AIMS: This study was undertaken to assess the genotoxic effect of panoramic radiography in the buccal epithelial cells. MATERIALS AND METHODS: The study included 60 healthy individuals (median age 23.5 years; age range 12-65 years) who underwent panoramic radiographic examination. Exfoliated buccal epithelial cells were obtained immediately before and 10 days after radiation exposure. The cells were stained with Giemsa and evaluated for micronuclei by scoring 1000 cells per sample. STATISTICAL ANALYSIS USED: The paired 't ' test was used to find out the significance of difference in the number of micronuclei before and after x-ray exposure. The Karl Pearson correlation coefficient was used to find out the correlation between age and micronucleated cell frequencies and number of micronucleus per 1000 cells. The ANOVA test was used to find out if there were significant differences in micronucleated cell frequencies between different age-groups. Student's unpaired 't' test was used to find out the significance of difference in micronucleated cell frequencies and number of micronucleus per 1000 cells between genders. RESULTS: The paired 't' test showed that micronucleated cell frequencies (P = 0.02) and number of micronucleus per 1000 cells (P = 0.047) were significantly higher after radiographic exposure. The mean number of micronucleated cells before and after radiation exposure were 0.48 ± 0.14 and 0.51 ± 0.15, respectively. There was statistically significant increase in the frequency of micronuclei in buccal epithelial cells after exposure to panoramic radiography. The correlation of micronucleus frequency with age and gender was statistically nonsignificant. CONCLUSIONS: The results indicate that panoramic radiography may induce genotoxic effects in buccal epithelial cells. Considering this risk, panoramic radiography should be used cautiously.

La hiperdontia en región de molares / Hyperdontia in molar region

La hiperdontia constituye una de las anomalías más estudiadas de la dentición humana. Esa alteración representa la aparición de uno o más dientes en cantidades mayores de lo normal, que puede ocurrir en la mandíbula o maxila y de manera unilateral o bilateral. La etiología de los dientes supernumerarios puede ser explicada principalmente por hiperactividad de la lámina dentaria en la fase inicial. Es importante la detección precoz de dientes supernumerarios porque se ha visto una serie de complicaciones como los diastemas, que pueden causar en la cavidad bucal: retardo de la erupción o dientes impactados, posicionamiento inadecuado de dientes permanentes, desajuste oclusal y el desarrollo de quistes y tumores odontógenos. Así el diagnóstico es normalmente realizado a partir de un examen radiográfico convencional, principalmente la radiografía panorámica. Este trabajo tuvo como objetivo relatar 4 casos clínicos de pacientes con presencia de molares supernumerarios, que fueron atendidos en el Servicio de Radiología de la Escuela de Odontología de la Universidad Federal de Ceará(AU)

Hyperdontia is one of the more studied anomalies of human dentition. This alteration represents the appearance of one or more teeth in a number greater of normal, occurring in mandible or in maxilla and could be unilateral or bilateral. The etiology of supernumerary teeth may be explained mainly due to the hyperactivity of dental plate in its initial phase; its early detection is important because of there have been a series of complications that may to cause diastemata, eruption retard or impacted teeth, inappropriate positioning of permanent teeth, occlusal misalignment and the development of odontogenic cysts or tumors. Thus, the diagnosis is normally made from a conventional radiographic examination, mainly the panoramic X-ray. The objective of present paper is the present four clinical cases of patients presenting with supernumerary molars, seen in the Radiology Service during the course of stomatology of the Federal University of Ceará(AU)

[Third molar and mandibular canal: selection of radiographic techniques]. / Dent de sagesse et nerf alvéolaire inférieur. Choix des examens radiographiques.

Injury of the inferior alveolar nerve during extraction of mandibular third molar is a well recognized, but uncommon, serious complication. It has a serious impact on oral function and its psychological impact on the patient is great. To prevent this complication, several studies have been conducted to identify the high-risk radiological signs associated with intimate anatomic relationships between third molar and infra-alveolar nerve and thereby establish a unified process of radiological exploration. In this paper, the authors present a review of the literature of the recent studies involving radiological exploration of the relation of the third molar with the mandibular canal.