Hallazgos en radiografías panorámicas de niños entre 6 y 15 años en un hospital odontológico en Argentina / Findings in panoramic radiographs of children between 6 and 15 years at a dental hospital in Argentina

Objetivo: Describir la frecuencia y localización de pato- logías y anomalías dentarias (anomalías de número, tumores, quistes y piezas retenidas) observadas en radiografías pa- norámicas de pacientes pediátricos de entre 6 y 15 años del Hospital Zonal Especializado en Odontología Infantil "Dr. A. Bollini" de la ciudad de La Plata. Materiales y métodos: Se realizó un estudio observa- cional descriptivo de 300 radiografías panorámicas, de niños (n=150) y niñas (n=150) de entre 6 y 15 años, seleccionadas aleatoriamente en el área de radiología del hospital, tomadas en el período comprendido entre marzo de 2018 y marzo de 2020. Los datos obtenidos se volcaron en planillas de cálculo y con ellos se realizó un análisis estadístico descriptivo. Se utilizaron las siguientes variables: edad, sexo, tipo de ano- malía o patología (anomalías de número, tumores, quistes y piezas retenidas), pieza dentaria y ubicación (maxilar o man- díbula). Resultados: Dentro de las anomalías registradas (n=147), se encontraron en mayor medida piezas dentarias retenidas, en un 44,22% de los casos (n=65), agenesias en un 42,18% de los casos (n=62) y supernumerarios en un 13,61% de los casos (n=20). No se hallaron quistes ni tumores. Conclusión: En un 24% de las radiografías panorámicas de niños entre 6 y 15 años se halló alguna anomalía dentaria. Las anomalías más frecuentes fueron piezas dentarias reteni- das y agenesias (AU)

Aim: To describe the frequency and location of dental pathologies and anomalies (number anomalies, tumors, cysts and retained dental pieces) observed in panoramic radio- graphs of pediatric patients between 6 and 15 years of age from the Hospital Especializado en Odontología Infantil "Dr. A. Bollini" from the city of La Plata. Materials and methods: A descriptive observational study was performed based on 300 panoramic radiographs of children (150 girls and 150 boys) between 6 and 15 years old, randomly selected in the Radiology area of the hospital, taken in the period between March 2018 and March 2020. The data obtained were entered into spreadsheets and a descriptive sta- tistical analysis was carried out. The following variables were evaluated: age, sex, type of anomaly or pathology (anomalies of number, tumor, cysts and retained dental pieces), dental piece and location (maxilla or mandible). Results: Among the registered anomalies (n=147), re- tained dental pieces were found to a greater extent, in 44.22% of the cases (n=65), agenesis in 42.18% of the cases (n=62) and supernumeraries in 13.61% of the cases (n=20). No cysts or tumors were found. Conclusion: In 24% of panoramic radiographs of chil- dren between 6 and 15 years old, some dental anomaly was found. The most frequent anomalies were retained dental pieces and agenesis (AU)

Prevalencia de agenesia dental en pacientes evaluados en ortodoncia, Santiago de Chile / Prevalence of dental agenesis in patients evaluated in orthodontics, Santiago de Chile

Resumen La agenesia dentaria es una anomalía frecuente de detectar en un examen odontológico. Objetivo: Determinar la prevalencia de agenesias en la población chilena actual, comparar según sexo, diente afectado y clase esqueletal, y registrar microdoncia de incisivos laterales superiores permanentes. Materiales y métodos: En este estudio descriptivo transversal, se contabilizó el número de agenesias dentarias presentes en 278 radiografías panorámicas de un total de 9207 pacientes, que ingresaron a tratamiento de ortodoncia durante el año 2017 en un centro clínico privado de Santiago de Chile. Resultados: Se obtuvo una prevalencia de agenesia del 3,02%, encontrando una mayor frecuencia de agenesia de segundos premolares inferiores, seguido de incisivos laterales superiores. Hubo una mayor cantidad de agenesias en pacientes de sexo femenino. Conclusión: Los segundos premolares son los dientes con mayor prevalencia de agenesias, no se evidenció la asociación de agenesias en alguna clase esqueletal específica, y se sugieren más estudios para describir la prevalencia de los terceros molares, debido a que este diente está en vías de dejar desarrollarse, según la teoría evolutiva.

Abstract Dental agenesis is a frequent anomaly detected in a dental examination. Objective: To determine the prevalence of agenesis in the current Chilean population, compare according to sex, affected tooth, skeletal class, and record microdontia of permanent upper lateral incisors. Materials and methods: In this cross-sectional descriptive study, the number of dental agenesis present in 278 panoramic radiographs of a total of 9207 patients who entered orthodontic treatment during 2017 in a private clinical center in Santiago de Chile was recorded. Results: A prevalence of agenesis of 3.02% was obtained, finding a higher frequency in lower second premolars, followed by upper lateral incisors. Females presented a higher amount of cases in comparison to males. Conclusion: The second premolars are the teeth with the highest prevalence of agenesis. The association of this alteration with some specific skeletal class was not evidenced. More studies are suggested to describe it´s prevalence in the third molars, beacause according to the evolutionary theory this tooth might eventually disappear.

Agenesis of third molars and its association with other dental anomalies in a peruvian population / Agenesia de terceros molares y su asociación con otras anomalías dentales en una población peruana

Objective: The purpose of the present study was to determine the association between agenesis of the third molar and other dental anomalies. Materials and Methods: This was an observational, retrospective, cross-sectional and analytical study. The sample included 367 patients, aged 14 to 20 years old with adequate digital panoramic radiography. Patients with syndromes, who had extractions of any third molar and with orthodontic treatment prior to panoramic radiographic examination, were excluded. For data collection, each radiograph was recorded with patient code, sex and age. Results: The prevalence of third molar agenesis was 20.71%. Subsequently, patients were divided into two groups, with agenesis of at least one third molar and a control group; the prevalence of other dental anomalies was 48.69% of third molar agenesis group and 21.31% in the control group. A highly significant association was found between the presence of third molar agenesis and the presence of other tooth abnomalities (p= 0.0000; contingency coefficient = 0.2425).The most frequent dental anomaly was dental inclusion with 20.44% of the population studied; followed by the agenesis of other teeth (7.90%) and finally the presence of supernumerary teeth (1.63%). Conclusions: This study demonstrates that there is an association between third molar agenesis and other dental abnormalities, with a higher prevalence of dental abnormalities in patients with third molar agenesis.

Objetivo: La presente investigación tuvo como finalidad determinar la asociación que existe entre la agenesia del tercer molar y otras anomalías dentarias. Material y Métodos: El estudio fue observacional, retrospectivo, transversal y analítico. La muestra que incluyó 367 pacientes de 14 a 20 años de edad con radiografía panorámica digital con parámetros adecuados. Se excluyeron pacientes con algún tipo de condición sindrómica, con exodoncias de algún tercer molar y con tratamiento ortodóntico previo al examen radiográfico panorámico. Para la recolección de datos, cada radiografía fue registrada con código de paciente, sexo, edad. Resultado: Se reportó una prevalencia de 20,71% de casos con agenesia de terceros molares. Los pacientes fueron divididos en 2 grupos, con agenesia de al menos un tercer molar y un grupo control, en ambos se calculó la prevalencia las otras anomalías dentarias, la cual fue de 48.69% de los pacientes que presentan agenesia de tercer molar tienen otra anomalía dentaria y 21.31% del grupo control tienen otra anomalía dentaria. Se encontró una asociación altamente significativa entre la presencia de agenesia de tercer molar y presencia de otras anomalías dentales (p=0.0000; coeficiente de contingencia=0.2425). La anomalía dental encontrada con más frecuencia es la inclusión dentaria con 20,44% del total de la población estudiada; seguido de la agenesia de otros dientes con 7,90% y finalmente la presencia de dientes supernumerarios con 1,63%. Conclusion: Este estudio demuestra que existe asociación entre la agenesia de tercer molar y otras anomalías dentarias, existiendo una mayor prevalencia de anomalías dentales en pacientes con agenesia del tercer molar.

Is third molar agenesis an anomaly or just a sign of variation? Prevalence and manner of presentation of this condition in a sample from the Metropolitan Region of Chile / ¿Es la agenesia del tercer molar una anomalía o simplemente un signo de variación? Prevalencia y forma de presentación de esta condición en una muestra de la Región Metropolitana de Chile

Agenesis of permanent teeth is the most frequent dental anomaly. The most affected tooth is the third molar (M3), and its congenital absence poses interesting questions from a clinical and evolutionary perspective. M3 agenesis can occur isolated or as part of syndromes. Researchers have reported prevalences that vary largely among populations, between 5 % and 56 %, with a mean prevalence of 22.6 %. Previous Chilean studies, mainly in Northern populations, have determined a prevalence between 19.8 % and 26.7 %. The aim of this work was to assess the prevalence of M3 agenesis and to characterize its presentation in a sample from Santiago, the largest to date in a M3 agenesis prevalence study in Chile. In this study, 535 panoramic radiographies and clinical histories of patients from the Dental Clinic of the Universidad de Chile were used to determine prevalence and distribution according to sex, affected tooth, and location (left or right; maxilla or mandible). The Chi-square test was used to assess statistical significance in distribution. The calculated M3 agenesis prevalence was of 12.89 %. No statistically significant differences were found between sexes, sides or location within the jaws. The agenesis of one third molar was more common, then two, three and finally of all the third molars. The prevalence of M3 agenesis in the sample is 12.89 %, with a random manner of presentation. We propose that as it currently stands, M3 agenesis should be considered an anatomical variation rather than a developmental anomaly.

La agenesia de dientes definitivos es la anomalía dental más común. El diente más afectado es el tercer molar (M3), y su ausencia congénita plantea preguntas interesantes desde una perspectiva clínica y evolutiva. La agenesia de M3 puede ocurrir de manera aislada o asociada a síndromes. Estudios a nivel mundial reportan una prevalencia variable entre poblaciones: 5 % a 56 %, con una prevalencia media del 22,6 %. Estudios chilenos anteriores, principalmente en poblaciones del norte, han determinado una prevalencia entre 19,8 % y 26,7 %. El objetivo de este trabajo fue determinar la prevalencia de agenesia de M3 y caracterizar su presentación en una muestra de Santiago, la más grande hasta la fecha en un estudio de prevalencia de agenesia de M3 en Chile. Se utilizaron 535 radiografías panorámicas y antecedentes de pacientes atendidos en la Clínica Odontológica de la Universidad de Chile para evaluar la prevalencia y modo de presentación de la agenesia de M3. Se analizó su distribución según ubicación, sexo y simetría, mediante test estadístico Chi-cuadrado. Se calculó una prevalencia de agenesia de M3 de 12,89 %, sin un patrón claro ni estadísticamente significativo en su distribución. Fue más común la agenesia de un tercer molar, luego de dos, tres y finalmente de todos los terceros molares. La prevalencia de agenesia en una muestra de la Región Metropolitana es de 12,89 % y su distribución es aleatoria según la ubicación, sexo y simetría. Se propone que esta condición actualmente debiera considerarse como una variación anatómica más que a una anomalía del desarrollo.

Peg Shaped Mandibular Lateral Incisor in a Hypodontia Patient: A Case Report.

Congenitally missing teeth are not rare. However, their association with other dental anomalies has always been a topic of interest in the profession. Occurrence of peg-shaped incisors in the mandibular arch is a rare finding. Strong association has been suggested between hypodontia and microdontia. Treatment approach has to be case specific and depends on the condition of primary predecessor, number of missing teeth, status of occlusion/occlusal condition and patient/parent’s preferences. This paper reports an unusual case of bilateral agenesis of permanent mandibular canines and unilateral agenesis of mandibular incisors, in association with a rare finding of peg-shaped mandibular lateral incisor in a 7-year-old Indian female.

Prevalence of dental anomalies of number in different subphenotypes of isolated cleft palate

OBJECTIVE: This study aimed at carrying out a radiographic analysis on the prevalence of dental anomalies of number (agenesis and supernumerary teeth) in permanent dentition, in different subphenotypes of isolated cleft palate pre-adolescent patients. METHODS: Panoramic radiographs of 300 patients aged between 9 and 12 years, with cleft palate and enrolled in a single treatment center, were retrospectively analyzed. The sample was divided into two groups according to the extension/severity of the cleft palate: complete and incomplete . The chi-square test was used for intergroup comparison regarding the prevalence of the investigated dental anomalies (P < 0.05). RESULTS: Agenesis was found in 34.14% of patients with complete cleft palate and in 30.27% of patients with incomplete cleft palate. Supernumerary teeth were found in 2.43% of patients with complete cleft palate and in 0.91% of patients with incomplete cleft palate. No statistically significant difference was found between groups with regard to the prevalence of agenesis and supernumerary teeth. There was no difference in cleft prevalence between genders within each study group. CONCLUSION: The prevalence of dental anomalies of number in pre-adolescents with cleft palate was higher than that reported for the general population. The severity of cleft palate did not seem to be associated with the prevalence of dental anomalies of number. .

OBJETIVO: o propósito deste estudo foi avaliar radiograficamente a prevalência das anomalias dentárias de número (agenesias e supranumerários), na dentição permanente, em diferentes subfenótipos da fissura isolada de palato, em pacientes pré-adolescentes. MÉTODOS: foram investigadas, de forma retrospectiva, 300 radiografias panorâmicas de pacientes com fissura palatina (pós-forame), de 9 a 12 anos de idade, matriculados em um mesmo centro. A amostra foi dividida em dois grupos de acordo com a extensão/gravidade da fissura palatina: completa e incompleta. O teste qui-quadrado foi utilizado para comparação intergrupos das prevalências de anomalias avaliadas (p < 0,05). RESULTADOS: a agenesia dentária foi encontrada em 34,14% dos pacientes com fissura pós-forame completa e em 30,27% com fissura pós-forame incompleta. A prevalência de dentes supranumerários correspondeu a 2,43% nos pacientes com fissura palatina completa e a 0,91% no grupo com fissura palatina incompleta. Não houve diferença estatística significativa entre os grupos quanto à prevalência de agenesias dentárias e supranumerários. Não se observou diferença sexual quanto à prevalência de fissura dentro de cada grupo de estudo. CONCLUSÃO: os pacientes pré-adolescentes com fissura palatina apresentam maior prevalência de anomalias dentárias em relação à população em geral. A gravidade da fissura palatina parece não se associar com a prevalência de anomalias dentárias de número. .

Agenesia de terceros molares, prevalencia, distribución y asociación con otras anomalías dentales / Third molar agenesis, prevalence, distribution and association with other dental anomalies

La agenesia de terceros molares se ha reportado en un 24,3 por ciento en México. La agenesia dental está asociada a otras anomalías dentales debido a su origen genético. El objetivo del presente estudio fue determinar la prevalencia y distribución de agenesia de terceros molares así como establecer su asociación con otras anomalías dentales en una población ortodóntica. La muestra incluyó 670 pacientes ortodónticos de 9 a 20 años de edad. Se excluyeron pacientes con tratamiento ortodóntico previo y condiciones sindrómicas. Se calculó la prevalencia de agenesia de terceros molares y se comparó por sexo. Posteriormente los pacientes fueron divididos en 2 grupos, con agenesia de al menos un tercer molar y un grupo control y en ambos se calculó la prevalencia de 10 anomalías dentarias. Los resultados se compararon por medio de la prueba exacta de Fisher (p<0,05). La prevalencia fue del 25,97 por ciento, no hubo diferencia estadística entre géneros (p=0,139). El 41,95 por ciento de los pacientes del grupo de agenesia presentó anomalías asociadas, mientras que en el control fueron el 23,59 por ciento. Se encontró una diferencia significativa entre ambos grupos (p=0,0001). Al comparar individualmente la prevalencia de cada anomalía por grupo, se encontró que la agenesia (p=0,0001) y los dientes retenidos (p=0,015) estaban disminuidos significativamente en el grupo control. En conclusión se encontró una prevalencia del 25,97 por ciento, sin preferencia de sexo. Los pacientes con agenesia de terceros molares presentan mayor prevalencia de anomalías dentales asociadas, particularmente agenesia de otros dientes y dientes retenidos.

Prevalence of third molar agenesis has been estimated in 24.3 percent in Mexico. Dental agenesis is associated with other dental anomalies due its genetic origin. The aim of this study was to determine the prevalence and distribution of third molar agenesis and to establish its association with other dental anomalies in an orthodontic population. The sample included 670 orthodontic patients from 9 to 20 years old. Exclusion criteria were patients with previous orthodontic treatment and syndromic conditions. Third molar agenesis prevalence was calculated and sex values were compared. Then, patients were divided into 2 groups, with agenesis of at least one third molar and a control group; prevalence of 10 dental anomalies were calculated for both groups. The results were compared using Fisher's exact test (p <0.05). Third molar agenesis prevalence was 25.97 percent, there was no statistical difference between sexes (p= 0.139). The 41.95 percent of patients in the agenesis group had abnormalities associated, whereas in the control group it was 23.59 percent. A significant difference between groups was found (p= 0.0001). When comparing the prevalence of each individual anomaly between groups, it was found that agenesis (p= 0.0001) and impacted teeth (p= 0.015) were significantly decreased in the control group. In conclusion it was found a prevalence of 25.97 percent, with no sex preference. Patients with agenesis of third molars have a higher prevalence of associated dental anomalies, particularly agenesis of other teeth and impacted teeth.

Prevalence of mesiodens in orthodontic patients with deciduous and mixed dentition and its association with other dental anomalies

OBJECTIVE: To determine the prevalence of mesiodens in deciduous and mixed dentitions and its association with other dental anomalies. MATERIAL AND METHODS: Panoramic radiographs of 1,995 orthodontic patients were analyzed retrospectively, obtaining a final sample of 30 patients with mesiodens. The following aspects were analyzed: gender ; number of mesiodens; proportion between erupted and non-erupted mesiodens; initial position of the supernumerary tooth; related complications; treatment plan accomplished; and associated dental anomalies. The frequency of dental anomalies in the sample was compared to reference values for the general population using the chi-square test (c²), with a significance level set at 5%. RESULTS: The prevalence of mesiodens was 1.5% more common among males (1.5:1). Most of the mesiodens were non-erupted (75%) and in a vertical position, facing the oral cavity. Extraction of the mesiodens was the most common treatment. The main complications associated with mesiodens were: delayed eruption of permanent incisors (34.28%) and midline diastema (28.57%). From all the dental anomalies analyzed, only the prevalence of maxillary lateral incisor agenesis was higher in comparison to the general population. CONCLUSION: There was a low prevalence of mesiodens (1.5%) in deciduous and mixed dentition and the condition was not associated with other dental anomalies, except for the maxillary lateral incisor agenesis.

OBJETIVO: determinar a prevalência de mesiodens nos estágios de dentição decídua e mista, e verificar sua associação com outras anomalias dentárias. MÉTODOS: radiografias panorâmicas de 1.995 pacientes ortodônticos foram analisadas retrospectivamente, obtendo-se uma amostra de 30 pacientes com o mesiodens. Os seguintes aspectos foram analisados: distribuição entre os sexos, número de mesiodens; se irrompido ou não irrompido; posição; complicações; tratamento instituído, e anomalias dentárias associadas. A frequência de anomalias dentárias na amostra estudada foi comparada a valores de referência para a população em geral por meio do teste qui-quadrado (c²), com um nível de significância de 5% (p < 0,05). RESULTADOS: a prevalência de mesiodens foi de 1,5%, sendo mais comum no sexo masculino (1,5:1). A maior parte dos mesiodens estavam não irrompidos (75%) e numa posição vertical, voltada para a cavidade bucal. O tratamento mais empregado foi a exodontia. As principais complicações associadas ao mesiodens foram o atraso na erupção dos incisivos permanentes (34,28%) e diastema mediano (28,57%). Pacientes com mesiodens não apresentaram prevalência aumentada de microdontia, agenesia de dentes permanentes ou outros supranumerários. De todas as anomalias analisadas, apenas a prevalência de agenesia de incisivo lateral superior mostrou-se aumentada em comparação à população em geral. CONCLUSÃO: o mesiodens foi encontrado em uma prevalência baixa (1,5%) nas dentições decídua e mista, e não apresentou associação com outras anomalias dentárias, com exceção da agenesia de incisivo lateral superior.

Msx1 Gene Variant - its Association in Isolated Hypodontia: A Case Control Genetic study!!!.

INTRODUCTION: Non‑syndromic tooth agenesis is a congenital anomaly with significant medical, psychological, and social ramifications. There is sufficient evidence to hypothesize that locus for this condition can be identified by candidate genes. AIM OF THE STUDY: The aim of this study was to test whether MSX1 671 T > C gene variant was involved in etiology of non‑syndromic tooth agenesis in Raichur patients. MATERIALS AND METHODS: Blood samples were collected with informed consent from 50 subjects having non‑syndromic tooth agenesis and 50 controls. Genomic deoxyribonucleic acid (DNA) was extracted from the blood samples, polymerase chain reaction (PCR) was performed, and restriction fragment length polymorphism (RFLP) was performed for digestion products that were evaluated. RESULTS: The results showed positive correlation between MSX1671 T > C gene variant and non‑syndromic tooth agenesis in Raichur patients. CONCLUSION: MSX1 671 T > C gene variant may be a good screening marker for non‑syndromic tooth agenesis in Raichur patients.

Hipodoncia y hueso navicular accesorio: una interesante asociación sindrómica / Hypodontia and accessory navicular bone: an interesting syndromic association

Los dientes se desarrollan a partir de múltiples interacciones recíprocas entre células del epitelio oral y el ectomesénquima. Una serie de genes participan en el desarrollo del diente, así como de otros órganos y miembros superiores e inferiores. PAX9, miembro de la familia de factores de transcripción, es uno de los principales responsables de este desarrollo, y juega un rol fundamental en la hipodoncia dental y malformaciones en los huesos del miembro inferior. El objetivo de este reporte es presentar un caso de asociación entre hipodoncia y el hueso navicular accesorio. Se trata de una paciente de 18 años de edad, que acude a la consulta dental por dolor agudo en la pieza dentaria 3.6 y dolor de 9 meses de evolución en la cara interna del pie izquierdo. Al examen radiográfico, se observó ausencia de las piezas dentarias 1.7, 2.7, 2.8, 3.8 y 4.8, además en el pie izquierdo se vio la presencia de un hueso navicular accesorio. Es interesante proponer esta rara asociación, de clara herencia autosómica dominante, dado que la agenesia dental y la presencia del hueso navicular accesorio, poseen una prevalencia semejante, lo que hace que pueda existir una nueva asociación sindrómica probablemente relacionada con la ausencia de PAX9(AU)

Teeth are developed from many interactions between oral epithelium and mesenchymal cells. A number of genes are involved in tooth development, as well as in other organs, and upper and lower limbs. PAX9, a member of the transcriptional factor family, is one of the main drivers of this development, playing a key role in dental hypodontia and malformations in the lower limb bones. The aim of this report was to present the association between hypodontia and the accessory navicular bone based on a case report. This is a 18 years old female patient, who attended a dental clinic because she had acute pain in the 3.6 tooth and also pain on the left foot's inner area. The radiographic examination showed loss of the teeth 1.7, 2.7, 2.8, 3.8 and 4.8; and the presence of an accessory navicular bone in the left foot. It is interesting to suggest that this rare association, with clear dominant autosomal inheritance, might exist; since the dental agenesis and the presence of accessory navicular bone have similar prevalence, which could point to a new syndromic association probably related to the lack of PAX9(AU)

Radiographic assessment of agenesis of third molars andpara-radicular third molar radiolucencies in populationof age group 18-25 years old: a radiographic survey / Avaliação radiográfica da gênese e radiolucidezperirradicular de terceiros molares em população de faixaetária de 18-25 anos: um levantamento radiográfico

Introduction: Due to biological, cultural and evolutionary changes with time, humans have experienced adecreased dependency on all tooth types. Because of this, the number of certain teeth which are no longernecessary for function are either getting increasingly impacted or are not developing at all. This is especiallythe case where third molars are concerned. Objective: To assess the prevalence of agenesis of third molarsand para-radicular third molar radiolucencies in population of age group 18-25 years. Materials and methods:Five hundred patients of age ranging from 18 to 25 years old were selected randomly and subjectedto undergo conventional panoramic radiographic procedure. Results: 35.4% patients of our study populationrevealed agenesis of one of the third molars among the four third molars. Agenesis of right maxillarythird molar is quite significant as p = 0.030; and only 3.4% revealed the prevalence of para-radicular thirdmolar radiolucencies. Conclusion: As time goes by, agenesis of the third molars is increasing, so they canbe considered as vestigial. However, etiology of the para-radicular third molar radiolucencies is unknown.Hence, further research is needed to describe the nature as well as outcome of mandibular para-radicularthird molar radiolucencies.

Introdução: Em virtude de alterações biológicas, culturais e evolutivas com o tempo, os seres humanos têmexperimentado uma diminuição da dependência em todos os tipos de dentes. Por isso, os dentes que já nãosão necessários para a função estão ficando cada vez mais impactados ou não estão sequer se desenvolvendo.Este é especialmente o caso dos terceiros molares. Objetivo: Avaliar a prevalência de agenesia dos terceirosmolares e radiolucidez perirradicular em terceiros molares em uma população com faixa etária de 18-25 anos.Materiais e métodos: Quinhentos pacientes entre 18-25 anos foram selecionados aleatoriamente e submetidosa um exame radiográfico panorâmico convencional. Resultados: 35,4% dos pacientes da população deestudo revelaram agenesia de um dos terceiros molares entre os quatro terceiros molares. Agenesia do terceiromolar superior direito foi bastante significativa com valor p = 0,030 e apenas 3,4% revelaram a prevalência deradiolucidez perirradicular nos terceiros molares. Conclusão: Com o tempo, a agenesia dos terceiros molaresestá aumentando, de modo que podem ser considerados vestigiais. Porém, a etiologia da radiolucidez perirradicularnos terceiros molares é desconhecida. Portanto, mais pesquisas são necessárias para descrever a natureza,bem como as consequências de radiolucidez perirradicular em terceiros molares inferiores.

Prevalencia de agenesia dental en niños con dentición mixta de las clínicas odontológicas docente asistencial de la Universidad de La Frontera / Prevalence of dental agenesis in children with mixed dentition of teaching assistant dental clinics at the Universidad de La Frontera

El objetivo de este estudio (corte transversal y descriptivo) es determinar la prevalencia de agenesia (hipodoncia) dental en niños con dentición mixta que asisten a las Clínicas Odontológicas Docente Asistencial de La Universidad de La Frontera, durante el año 2009. Se examinaron 307 niños entre 6 y 11 años, que cumplían con los criterios de inclusión. La prevalencia de agenesia en la población estudiada fue de 4.2 por ciento (13/307), resultando más afectados los individuos de sexo femenino 5,9 por ciento (9/153). De acuerdo al orden de frecuencia, el diente más afectado por agenesia fue el segundo premolar inferior, con un valor de 4,2 por ciento (13/307). Le siguen, el segundo premolar superior, cuyo valor fue de 3,3 por ciento (10/307), 1,3 por ciento (4/307) del incisivo lateral inferior y 0,33 por ciento (1/307) del primer premolar superior. No se encontraron hallazgos radiográficos de agenesia en incisivo lateral superior y primer premolar inferior. Este estudio nos permitió obtener indicadores significativos de la población estudiada, como además señalar la importancia del diagnóstico precoz de esta anomalía, que conlleva a interceptar alteraciones de maloclusión.

The purpose of this study (cross sectional and descriptive) was to determine the prevalence of dental agenesis (hypodontia) in children with mixed dentition attending the teaching assistant dental clinics at the Universidad de La Frontera, 2009. We examined 307 children between 6 and 11 years, who met the inclusion criteria. The prevalence of agenesis in the studied population was 4.2 percent (13/307), with female individuals being the most affected, 5.9 percent (9/153). According to the order of frequency, the most affected by tooth agenesis was the second premolar, with a value of 4.2 percent (13/307). Followed by the second premolar, the value was 3.3 percent (10/307), 1.3 percent (4/307) of the lateral incisor and 0.33 percent (1/307) of the first premolar. There were no radiographic findings of agenesis of upper lateral incisor and first premolar. This study allowed us to obtain significant indicators of the population studied, and also note the importance of early diagnosis of this anomaly, which leads to intercept alterations in the occlusion.

Prevalence of hypodontia in nine- to fourteen-year-old children who attended the Mashhad School of Dentistry.

Context: Hypodontia is defined as the congenital absence of one or a few teeth, and is also the most common anomaly in dental development. This condition occurs either individually or as part of the symptoms of a syndrome, and it is more common in permanent teeth than in deciduous teeth, reporting a prevalence of between 1.6 and 9.6%. Aims: The objective of this study is to investigate the prevalence of hypodontia for permanent teeth in nine- to 14-year-old children who attended the Mashhad School of Dentistry in 2007. Setting and Design: We conducted this descriptive, analytical, cross-sectional study, to determine the mentioned aims. Materials and Methods: In this descriptive, cross-sectional study, panoramic radiographs belonging to 600 children (351 girls and 249 boys), aged nine to 14 years, were available for examination. All related findings were recorded in the respective forms. Statistical Analysis Used: The data were processed using Exact and Chi-square tests. Results: The prevalence of hypodontia in the girls was 9.2%, in the boys 8.8%, and in both sexes combined 9%. The most and the least frequent cases of absent teeth were the mandibular second premolars and the maxillary central incisor (only one child), respectively. The most commonly absent teeth were the mandibular second premolars, the maxillary lateral incisors, the mandibular central incisor, and the maxillary second premolars, in that order. Conclusions: This study showed a high frequency of hypodontia among the understudied population. Thus, due to the complicated treatment, accurate examination of children for on-time diagnosis of this developmental anomaly is crucial.

Levantamento da prevalência de agenesias dentais em pacientes com idade entre 7 e 16 anos / Survey of the prevalence of dental agenesias in patients between 7 and 16 years old

Objetivo: Avaliar a prevalência das agenesias dentais em pacientes com idades entre 7 e 16 anos, do município de Campo Grande, Mato Grosso do Sul, a partir da análise de radiografias panorâmicas, no período de 2005 a 2007. Métodos: Foram analisadas 1 500 radiografias panorâmicas, 750 do sexo masculino e 750 do sexo feminino, por um único operador. Resultados: Os dados das amostras foram analisados estatisticamente pelos testes qui-quadrado, t-Student e Análise de Variância com nível de significância de 5%, sendo encontrada a presença de agenesia em 40,6% dos pacientes. Foi demonstrado não haver influência do gênero na ocorrência da agenesia dental. O dente que apresentou maior frequência deste tipo de anomalia foi o terceiro molar, seguido pelo segundo pré-molar (principalmente os inferiores), incisivo lateral superior e primeiro pré-molar superior. Embora não existindo diferença estatisticamente significativa em relação aos demais quadrantes, a localização mais frequente ocorreu na mandíbula, no quadrante inferior direito. Conclusão: Foi encontrada uma prevalência alta de agenesias, não havendo diferença estatisticamente significativa em relação ao gênero. Existiram diferenças estatísticas significativas entre as médias das agenesias com relação aos dentes. Quanto à localização não foram encontradas diferenças na presença da anomalia.

Objective: To assess the prevalence of dental agenesias in patients between the ages of 7 and 16 years, in the city of Campo Grande, Mato Grosso do Sul, from the analysis of panoramic radiographs from 2005 to 2007. Methods: A single operator analyzed 1,500 panoramic radiographs of patients, 750 being men and 750 women. Results: The data of the samples were statistically analyzed by the Chi-square and Student's-t tests, and ANOVA with a level of significance of 5%, and the presence of agenesias was found in 40.6% of the patients. It was demonstrated that gender had no influence of gender on the occurrence of dental agenesia. The tooth that had a highest frequency of this type of anomaly was the third molar, followed by the second premolar (particularly the mandibular teeth), maxillary lateral incisor and maxillary first pre-molar. Although there was no statistically significant difference in comparison with other quadrants, the most frequent localization occurred in the mandible, in the mandibular right quadrant. Conclusion: A high prevalence of agenesias was found, with no statistically significant difference with regard to gender. There were no statistically significant differences between the means of agenesias with regard to the teeth. Whereas, no differences in the presence of the anomaly were found as regards location.

Characteristics and distribution of dental anomalies in a Brazilian cleft population / Características e distribuição de anomalias dentárias em uma população brasileira de portadores de fissuras lábio-palatais

Purpose: To determine the prevalence of dental anomalies in 200 cleft patients undergoing orthodontic treatment at the Cleft Rehabilitation Center (CERLAP) of the Pontifical Catholic University of Rio Grande do Sul. Methods: Data regarding patient age, race, gender, cleft type (lip and alveolus, complete lip and palate, or cleft palate), affected side (unilateral or bilateral), agenesis and supernumerary teeth in both arches were assessed from orthodontic records comprised by panoramic, cephalometric, occlusal, and periapical radiographs, study models, intra- and extraoral photographs, obtained at the beginning of the treatment, providing needed information to make an accurate diagnosis of dental anomalies. The collected data were registered in spreadsheets. Results: The mean patient age was 13.5 years old; 86% were white; and 57% male. Complete cleft lip and palate was found at a higher frequency (83%); the left side was most affected (48.5%). Agenesis were found in 66.5% of patients. Maxillary lateral incisors were the most absent teeth (78.5%). Supernumerary teeth were found in 35.5% of patients. Conclusion: Male individuals demonstrated a greater tendency to present clefts and manifest both agenesis and supernumerary teeth. Complete cleft lip and palate prevailed, and the left maxillary lateral incisor was the most absent tooth. Supernumeraries were located distally to the cleft.

Objetivos: Determinar a prevalência de anomalias dentárias em 200 pacientes com fissura sob tratamento ortodôntico no Centro de Reabilitação Lábio-Palatal (CERLAP) da Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS). Metodologia: Os dados referentes à idade, raça, gênero, tipo de fissura (pré, trans ou pós-forame incisivo), lado afetado (uni ou bilateral), agenesias e supranumerários em ambas arcadas foram avaliados a partir da documentação ortodôntica constituída por radiografias panorâmicas, cefalométricas, oclusais e periapicais, modelos de estudo e fotografias intra e extrabucais obtidas no início do tratamento, fornecendo informações necessárias para diagnóstico de anomalias dentárias. Os dados coletados foram registrados em planilhas. Resultados: A média de idade dos pacientes foi de 13.5 anos; 86% eram brancos; e 57% eram meninos. Fissuras transforame incisivo demonstraram-se mais frequentes (83%); o lado esquerdo foi mais afetado (48.5%). Agenesias foram encontradas em 66.5% dos pacientes. Incisivos laterais superiores foram os dentes mais ausentes (78.5%). Supranumerários foram encontrados em 35.5 % dos pacientes. Conclusão: Meninos demonstraram maior tendência a apresentar fissuras e a manifestar agenesias dentárias e supranumerários. As fissuras completas de lábio e palato prevaleceram e os incisivos laterais superiores foram os dentes mais ausentes. Os supranumerários localiza-ram-se distalmente à fissura na maioria dos casos.

Agenesia del tercer molar en pacientes atendidos en la clínica odontológica de la Universidad de Antofagasta, Chile / Third molar agenesis in patients of dental clinic of the Universidad de Antofagasta, Chile

Se define agenesia como la ausencia de dientes por alteraciones genéticas aisladas o sindrómicas. La agenesia del tercer molar está asociada a malformaciones y es considerada por diversos autores, consecuencia de la evolución humana (Larmour et al., 2005). Son los dientes con mayor prevalencia de agenesia junto con segundos premolares e incisivos laterales (Fuller & Denehy, 1984). La prevalencia varía entre 9% y 37% (McNamara & Foley, 2006); Arboleda et al. (2006) señalan una prevalencia del 20%. La literatura indica variables estadísticas porcentuales, por género, por arcada dentaria, por lado y por diente, con escasos artículos sobre grupos originarios de Chile. La población en estudio consistió en 52 hombres y 48 mujeres, de 14 a 26 años de edad, pacientes de la Clínica Odontológica de la Universidad de Antofagasta. Todos los individuos eran sanos, sin ninguna malformación general o maxilofacial, no habían presentado enfermedades infecciosas que afectaran la odontogénesis y los períodos de erupción dentarios, sin exodoncias de ningún tercer molar y tratamiento ortodóncico previo al examen radiográfico panorámico. Se determina un 20,0% de casos de agenesia, con 8,25% de agenesia, respecto a número total de terceros molares y 1,03% de agenesia de terceros molares en relación al total de dientes. No se determina ninguna diferencia estadística significativa al 95% de confianza, predominando la agenesia en el género femenino, a nivel maxilar, en el lado izquierdo, de tipo simple, siendo el tercer molar superior izquierdo el diente que presenta el mayor número de casos de agenesia.

Agenesis is defined as the absence of teeth by genetic alterations isolated or syndromic. Agenesis of third molar is associated to malformations and is considerate by diverse authors as a consequence of human evolution (Larmour et al, 2005). The third molars are teeth with higher prevalence of agenesis together with seconds premolars and lateral incisive (Fuller & Denehy, 1984). The prevalence varies between 9 percent to 37% (McNamara & Foley, 2006). Arboleda et al. (2006) indicated a prevalence of 20%. The literature notes statistical variables percentage by gender, dental arch, side, and tooth, with few articles on groups originating from Chile. The population in study consisted of 52 men and 48 women between 14 and 26 years old, patients of the dental clinic of the Universidad de Antofagasta. All individuals were healthy, without any general or maxillofacial malformation without infectious diseases affecting the odontogenesis and dental eruption, without extractions of third molar and orthodontic treatment prior to the panoramic x-ray. A 20% of individuals with agenesis was determined, with 8.25% of agenesis respect the total number of third molars and 1.03% agenesis respect the total number of teeth. Statistical analyses did not show significant differences at 95% level, with agenesis of third molar prevalence in females, in maxilla, in the left side, simple, being the left maxillary third molar the tooth that present many number of agenesis.

Agenesia del tercer molar en una etnia originaria del Norte de Chile: Aymaras / Third molar agenesis in native ethnia from North of Chile: Aymaras

Agenesia es la ausencia de dientes por alteraciones genéticas aisladas o sindrómicas. La agenesia del tercer molar está asociada a malformaciones y es considerada por diversos autores consecuencia de la evolución humana (Larmour et al, 2005). Son los dientes con mayor prevalencia de agenesia junto con segundos premolares e incisivos laterales (Fuller & Denehy, 1984). La prevalen-cia varía entre 9 por ciento y 37 por ciento (McNamara & Foley, 2006), en tanto Arboleda et al. (2006) señalan una prevalencia del 20 por ciento. La literatura señala variables estadísticas porcentuales, por género, por arcada dentaria, por lado y por diente, con escasos artículos sobre grupos originarios de Chile. La población en estudio consistió en 78 individuos, 42 hombres y 36 mujeres, entre 18 y 40 años, de la etnia aymara, sin exodoncias del tercer molar ni tratamientos ortodónticos y sin malformaciones congénitas. Se determinó el grado de mestizaje mediante técnica sero lógica de hemo-aglutinación y por aplicación de la fórmula de Bernstein, que demostró 51 por ciento de mezcla indígena. A cada individuo se le tomó radiografía panorámica para observar presencia o ausencia de terceros molares. Se determinó un 21,79 por ciento de agenesia, con mayor porcentaje masculino. En la muestra total y en hombres hay mayor agenesia de terceros molares mandibulares, en cambio en mujeres existe igual porcentaje de agenesia en ambas arcadas. Predominan agenesias izquierdas, lo mismo se comprueba en el género masculino, mientras que en mujeres se comprueba igual porcentaje bilateral. Predomina la agenesia de un solo molar en ambos sexos. Nuestros resultados fueron comparados con atácamenos y con jóvenes antofagastinos y no se determinaron diferencias significativas al 95 por ciento, coincidiendo con lo señalado en la literatura. La investigación representa un aporte a la antropología del norte de Chile, pero considerando lo reducido de la muestra no es posible determinar...

Agenesis is the absence of teeth by genetic alterations, single or as syndrome. Agenesis of third molar is associated to malformations and is considered by diverse authors a consequence of the human evolution (Larmour et al., 2005). The third molars together with second premolars and lateral incisors are the teeth with greater prevalence of agenesis (Fuller & Denehy, 1984). The prevalence varies between 9 percent and 37 percent (McNamara & Foley, 2006); Arboleda et al. (2006) indicated a prevalence of 20 percent. Literature indicate variable percentage, by gender, dental arches, side and tooth, with few articles on original groups of Chile. The population in study consisted in 78 cases, 42 men and 36 women between 18 and 40 years of the ethnic group of aymarás, without extractions of third molar nor orthodontic treatments and without congenital malformations. Hybridism was determined by means of serum technique by blood agglutination and by application of the formula of Bernstein, demonstrated a 51 percent of indigenous mixture. To each individual a panoramic x-ray was taken to observe presence or absence of third molars. A 21.79 percent of agenesis was determined, with greater percentage among males. Agenesis lower third molar predominates in the sample and in men; however in women are greater agenesis upper third molar. In addition, agenesis predominates of the left side in both sexes, while in men equal bilateral percentage is verified. Agenesis of two molars predominates in both sexes. Our results be are compared with atácamenos and young people living in Antofagasta and statistical analyses did not show significant differences at the 95 percent level, and the results and, in general, agree with those in the literature. This research represents a contribution to the anthropology of the north of Chile, but it is not possible to determine ethnic variables considering the small sample in study.

Prevalencia de agenesia dentaria en pacientes que intresaron al Servicio de Ortopedia del Hospital Juan U. Carrea, Olivos, Buenos Aires, Argentina / Prevalence of dental agenesis in patients entering the Orthopedics Service of Dr. Juan U. Carrea Hospital, Olivos, Buenos Aires, Argentina

Objetivo: Determinar la prevalencia de agenesia dentaria en pacientes que ingresaron al servicio de ortopedia del Hospital Dr. Juan U. Carrea entre abril 2007 y marzo 2008. Materiales y Métodos: Análisis clínico-radiográfico. Registro de casos en una hoja de cálculo, con las siguientes variables: sexo, pieza dentaria afectada, maxilar y lado afectado. Resultados: De 1.315 pacientes, 3,95 por ciento presentó agenesia, de los cuales: 51,9 por ciento pertenecía al sexo femenino; 50 por ciento presentó ausencia de una pieza; la más frecuentemente ausente fue el segundo premolar inferior izquierdo con 30,12 por ciento; sólo 9,61 por ciento tenía conocimiento de antecedentes hereditarios y 7,69 por ciento presentó alguna anomalía dentaria asociada. Conclusión: No se observaron diferencias entre ambos sexos. La pieza más afectada fue el segundo premolar inferior izquierdo. La mayoría de los pacientes presentó agenesia de una pieza. Un bajo porcentaje, relató antecedentes hereditarios. Se observó asociación entre agenesia y anomalía dentaria en escasa cantidad de pacientes.

Agenesia de terceros molares en pacientes de la Facultad de Odontología de la UNAM / Agenesia of the third molars in patients of the Faculty of Odontology of the National Autonomous University of Mexico

ANTECEDENTES: los terceros molares o serotinos son los últimos dientes en erupcionar; su presencia genera diversas patologías como apiñamiento, pericoronitis y dolor, generalmente por falta de espacio en los maxilares. Según la filogenia humana son considerados dientes en vías de extinción. Cada vez más presentan una erupción retrasada e incluso ausencia por falta de formación. OBJETIVO: determinar la frecuencia de agenesia de terceros molares en pacientes de la Facultad de Odontología de la Universidad Nacíonal Autónoma de México. MÉTODOS: se examinaron 915 ortopantomografías de pacientes de 16 a 24 años y se realizó el diagnóstico de presencia de los terceros molares, se recabó información sociodemográfica y se analizó la asociación con el sexo usando X². RESULTADOS: el 20 por ciento de la muestra presentó agenesia de los 4 terceros molares, 56 por ciento tuvo los 4, y 24 por ciento solo de 1 a 3, además se encontró que el sexo no determina la presencia de los terceros molares (X²= 0,503, p= 0,478). CONCLUSIONES: la frecuencia de agenesia de terceros molares fue del 20 por ciento y esta es independiente del sexo(AU)

ANTECEDENTS: the third molars are the last teeth to erupt. Their presence generate diverse pathologies as crowding, pericoronitis and pain, generally due to the lack of space in the maxillae. According to human phylogeny, they are considered teeth on the way to extinction. They present an increasingly delayed eruption and even absence due to lack of formation, OBJECTIVE: to determine the frequency of agenesia of the third molars in patients of the Faculty of Odontology of the National Autonomous University of Mexico. METHODS: 915 orthopantomographies of patients aged 16-24 were examined and the diagnosis of presence of the third molars was made. Sociodemographic information was necessary and the association with sex was analyzed by using X2. RESULTS: 20 percent of the sample presented agenesia of the 4 third molars, 56 percent had the 4, and 24 percent only from 1 to 3. Besides, it was found that sex does not determine the presence of the third molars (X2= 0.503, p= 0.478). CONCLUSIONS: the frequency of agenesia of the third molars was 20 percent and it is independent of sex(AU)

Agenesia del tercer molar en jóvenes entre 14 y 20 años de edad, Antofagasta, Chile / Third molar agenesis in young people between 14 and 20 years of age, Antofagasta, Chile

Se define agenesia como la ausencia de dientes por alteraciones genéticas aisladas o sindrómicas. La agenesia del tercer molar está asociada a malformaciones y considerada por diversos autores, consecuencia de la evolución humana. Son los dientes con mayor prevalencia de agenesia junto con segundos premolares e incisivos laterales. La prevalencia varía entre 9 por ciento y 37 por ciento, en tanto, Arboleda et al. (2006) señalan una prevalencia del 20 por ciento. La literatura señala variables estadísticas porcentuales, por género, por arcada dentaria, por lado y por diente, con escasos artículos sobre grupos originarios de Chile. La población en estudio consistió en 400 jóvenes (200 hombres y 200 mujeres) entre 14 y 20 años de edad pacientes de una clínica de ortodoncia de la ciudad de Antofagasta, Chile. Todos los pacientes debían ser sanos, sin ningún tipo de malformación general ni maxilofacial, que no hubiesen presentado enfermedades infecciosas que alteraran la odontogénesis y los períodos de erupción, sin exodoncias de ningún tercer molar y sin tratamiento ortodóncico previo al examen radiográfico panorámico. Se determina un 24,75 por ciento de casos de agenesia, con un porcentaje de agenesia respecto del número total terceros molares de un 12,63 por ciento y un 1,58 por ciento de agenesia de terceros molares, en relación al total de dientes. Predomina la agenesia en el género femenino, a nivel mandibular, en el lado derecho, de tipo doble y siendo el diente prevalente el tercer molar mandibular derecho, sin presentarse diferencias estadísticas significativas al 95 por ciento de confianza.

Agenesis is defined as the absence of teeth by single or sindromics genetic alterations. Third molar agenesis is associated to malformations and is considered a consequence of human evolution by several authors. Third molar are the teeth with greater percentage of agenesis along with seconds premolars and lateral incisors. The frequency varies between 9 percent and 37 percent, while Arboleda et al., (2006) indicate a 20 percent of agenesis. Literature indicates statistical variables percentage, by gender, dental arches, side and tooth, however few articles in original groups of Chile. The population in study consisted of 400 young people (200 men and 200 women) between 14 and 20 years of age patient of a clinic of orthodontia of the city of Antofagasta, Chile. All the patients had to be healthy, without any type of general and maxillofacial malformation, who had not presented infectious diseases that altered the odontogenesis and the periods of eruption, without exodontias of third molar and without previous orthodontic treatment to the panoramic x-ray examination. A 24.75 percent of cases of agenesis were determined, with a percentage of 12.63 percent of agenesis with respect to the total number of third molars and 1.58 percent of agenesis of third molar in relation to the total of teeth. Agenesis in the female predominates, at mandibular level, in the right side, of double type and being the prevalent tooth is mandibular right third molar, without appearing significant statistical differences to 95 percent of confidence.