Alveolar morphometry in young adults with and without agenesis of the upper lateral incisor: A retrospective study.

INTRODUCTION: We aimed to compare alveolar morphometry in young adults with agenesis of the upper lateral incisor versus the side without agenesis and versus matched controls. MATERIAL AND METHODS: In this observational retrospective study, cone beam computed tomography scans were obtained of 36 upper hemiarches from young adults aged 15 to 30 years. The hemiarches were distributed into three groups: group 1: 12 upper hemiarches presenting agenesis of the upper lateral incisor; group 2: 12 upper hemiarches from the opposite side without agenesis of the upper lateral incisor (control group 1); and group 3: 12 upper hemiarches without agenesis of the upper lateral incisor matched for age and sex with respect to the affected group (control group 2). A trained and calibrated investigator performed all the alveolar measurements at two different times, including sagittal, coronal and axial slices of each hemiarch. Paired Student's t-tests, Chi-square and repeated measures ANOVA with Bonferroni correction were used, (P<0.05). RESULTS: Apical mesial evaluation of group 1 (4.22±1.19mm) was significantly lower (P<0.001) than that of groups 2 (6.72±1.17mm) and 3 (7.58±1.67mm). Apical distal evaluation also showed differences (P<0.001) among the three groups, with the dimension being smaller in group 1 with agenesis (4.53±1.14mm), followed by group 2 without agenesis (6.23±1.55mm) and the healthy control group 3 (7.73±1.71mm). CONCLUSIONS: Lateral incisor agenesis significantly reduces the alveolar dimensions of the affected area. In cases of unilateral agenesis, the unaffected side also shows sequelae, with decreased dimensions compared to cases without agenesis. This condition should be taken into account when making therapeutic decisions regarding rehabilitation with implants or canine replacement.

Rare and Multiple Hypodontia in Van der Woude Syndrome: Case Report.

Van der Woude syndrome (VWS) is a rare syndrome of genetic etiology, commonly occasioned by mutations in the IRF6 gene and that causes disorders in craniofacial development. VWS is characterized by the presence of paramedian fistulas in the lower lip and cleft lip and / or cleft palate. Although some dental phenotypes have been reported in this syndrome, multiple and rare hypodontias were not described. Through this case report, we present a case of Van der Woude Syndrome (VWS) with rare and multiple hypodontia in which clinical data and radiographic exams were evaluated. The patient presented hypodontia of eight permanent teeth (lateral incisors, second premolars and second molars). So, when the dentist recognizes multiple and/or rare hypodontias, for an accurate diagnosis, detailed examination of the lower lip is indicated, as well as a survey of the family history and referral for genetic counseling, since the syndrome presents high penetrance. The patient is expected to be rehabilitated to have a good quality of life. Rehabilitation in these cases requires alveolar bone graft, orthodontics and prosthesis to replace missing teeth.

Detección polimórfica del rs104893850 de MSX1 y rs28933373 de PAX9 en personas con agenesia dental no sindrómica / Polymorphic detection of rs104893850 of MSX1 and rs28933373 of PAX9 in people with non syndromic dental agnesia

Introducción: la agenesia dental no sindrómica (ADNS) genera efec- tos negativos en la salud oral y psicosocial de los seres humanos. El determinante genético desempeña un papel importante en su desarrollo. Objetivo: determinar la frecuencia de los polimorfismos rs104893850 de MSX1 y rs28933373 de PAX9 en pacientes de seis a 18 años con ADNS. Material y métodos: estudio transversal prolectivo en el cual se revisaron individuos de seis a 18 años sin defectos congénitos y originarios del estado de Durango. Después de haber obtenido su con- sentimiento para formar parte del estudio, se estableció el diagnóstico de ADNS a través de una inspección clínica odontológica y un examen radiográfico. Se tomó una muestra de sangre capilar para la genotipi- ficación de los polimorfismos a través de la técnica de qPCR-HRM. Resultados: de un total de 124 individuos, 77 (62%) mujeres y 47 (38%) hombres; sólo 39 presentaron ADNS. En el análisis polimórfico de rs104893850 de MSX1 y rs28933373 de PAX9 se obtuvo 94.9% y 84.6% respectivamente de homocigotos mutados. Conclusiones: se obtuvo una alta frecuencia de hipodoncia, el diente que mostró más agenesia fue el órgano dentario 18. Las mutaciones polimórficas están presentes en una alta proporción de agenesia dental (AU)

Introduction: non-syndromic dental agenesis (NSDA) generates negative oral health and psychosocial effects in humans. The genetic determinant plays an important role in its development. Objective: to determine the frequency of MSX1 rs104893850 and PAX9 rs28933373 polymorphisms in patients aged 6 to 18 years with NSDA. Material and methods: prolective cross-sectional study, in which individuals aged 6 to 18 years without congenital defects and from the city of Durango were reviewed. After obtaining their consent to be part of the study, the diagnosis of NSDA was established through a clinical dental inspection, a radiographic examination and a capillary blood sample was taken for the genotyping of the polymorphisms through the qPCR-HRM technique. Results: out of a total of 124 individuals, 77 (62%) females and 47 (38%) males; only 39 presented ADNS. In the polymorphic analysis of rs104893850 of MSX1 and rs28933373 of PAX9 we obtained 94.9% and 84.6% respectively of mutated homozygotes. Conclusions: a high frequency of hypodontia was obtained, and the tooth that presented the most agenesis was dental organ 18. Polymorphic mutations are present in a high proportion for dental agenesis (AU)

Dental anomalies frequency in submucous cleft palate versus complete cleft palate.

BACKGROUND/OBJECTIVES: This retrospective study evaluated the prevalence of dental anomalies of number in different subphenotypes of isolated cleft palate. MATERIALS/METHODS: The sample comprised 26 individuals with submucous cleft palate (group S) and 68 individuals with complete cleft palate (group C) aged between 9 and 12 years from a single centre. Panoramic radiographs were evaluated regarding the presence of dental anomalies of number in permanent teeth. Intergroup comparison was performed using chi-square tests (P < 0.05). RESULTS: Tooth agenesis was found in 34.61 and 36.76 per cent of group S and group C, respectively. The most commonly missing teeth were the maxillary second premolar, maxillary lateral incisor, and mandibular second premolar. Supernumerary teeth were found in none and 1.47 per cent of the individuals with submucous and complete cleft palate, respectively. No statistically significant difference was found between groups for the frequency of tooth agenesis and supernumerary teeth. LIMITATIONS: Only dental anomalies of number were evaluated. CONCLUSIONS/IMPLICATIONS: Individuals with submucous and complete cleft palate showed similar prevalence for tooth agenesis and supernumerary teeth. Dental anomalies frequency seems not to be a discriminator for subphenotypes of cleft palate.

Association between hypodontia of permanent maxillary lateral incisors and other dental anomalies

ABSTRACT Introduction: Tooth agenesis is often associated with other tooth anomalies, such as microdontia, delayed eruption and ectopic eruption. Moreover, they may be found all in the same individual, as certain genetic mutations may have a variable phenotypic expression. Treatment of cases of hypodontia of anterior teeth should not involve only opening or closing space for prosthetic rehabilitation. Individuals with hypodontia of permanent maxillary lateral incisors may have teeth with a mesiodistal width smaller than that of patients with a normal dentition, and which may need reshaping to achieve an esthetic and functional occlusion. Objective: This clinical case report discusses the association of hypodontia of permanent maxillary lateral incisors with other tooth anomalies and their treatment alternatives.

RESUMO Introdução: As agenesias dentárias são frequentemente associadas a outras anomalias dentárias, tais como microdontia, atraso na erupção e ectopismo. Além disso, podem vir todas juntas em um mesmo indivíduo, pois certas mutações genéticas podem se expressar fenotipicamente de diferentes formas. A abordagem terapêutica nos casos de hipodontia de dentes anteriores não deve se pautar somente entre fechar ou abrir espaço para substituição protética. Portadores de hipodontia de incisivos laterais superiores permanentes podem apresentar os outros dentes com largura mesiodistal menor que os de pacientes com dentição normal, e podem necessitar de reanatomizações para que se obtenha uma oclusão dentária estética e funcional. Objetivo: Dessa forma, o objetivo do presente artigo é relatar um caso clínico e discutir a associação da hipodontia de incisivos laterais superiores permanentes com outras anomalias dentárias, e suas alternativas de tratamento.

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.

Maxillary incisor root morphology in patients with nonsyndromic tooth agenesis: A controlled cross-sectional pilot study.

INTRODUCTION: This study aimed to investigate the association between root morphology of maxillary incisors and nonsyndromic tooth agenesis in patients compared with a control group without agenesis. METHODS: This controlled cross-sectional pilot study (1:4) was performed with a random sample of 335 records from Brazilian applicants for orthodontic treatment, paired by sex and age. Panoramic and periapical radiographs were analyzed to diagnose tooth agenesis and to assess root morphology. The agenesis group (n = 67) included patients with nonsyndromic tooth agenesis, and the control group (n = 268) included patients without tooth agenesis. The statistical analysis included the Student t test and z test, conditional logistic regression, and odds ratio estimates. RESULTS: Occurrence of root morphological changes was significantly higher among patients with agenesis (P <0.05). Significant morphological changes (short, blunt, apically bent, and pipette-shaped roots) were found in the roots of remaining teeth when comparing agenesis and control groups (P <0.05). Patients with agenesis were more likely to show root morphological changes (odds ratio, 74.23; 95% confidence interval, 16.93-325.46; P <0.001). CONCLUSION: Patients with agenesis are more likely to present root morphological changes, which should be considered to minimize problems during orthodontic treatments.

Association between hypodontia of permanent maxillary lateral incisors and other dental anomalies.

INTRODUCTION: Tooth agenesis is often associated with other tooth anomalies, such as microdontia, delayed eruption and ectopic eruption. Moreover, they may be found all in the same individual, as certain genetic mutations may have a variable phenotypic expression. Treatment of cases of hypodontia of anterior teeth should not involve only opening or closing space for prosthetic rehabilitation. Individuals with hypodontia of permanent maxillary lateral incisors may have teeth with a mesiodistal width smaller than that of patients with a normal dentition, and which may need reshaping to achieve an esthetic and functional occlusion. OBJECTIVE: This clinical case report discusses the association of hypodontia of permanent maxillary lateral incisors with other tooth anomalies and their treatment alternatives.

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.

Novel dental phenotype in non-syndromic Pierre Robin Sequence: A retrospective study.

OBJECTIVE: The objective was to investigate dental phenotypes in individuals with non-syndromic Pierre Robin Sequence (ns-PRS) and compare the prevalence of these phenotypes with subjects with non-syndromic cleft palate (ns-CP) and a control group with subjects without any craniofacial anomalies. METHODS: A total of 760 panoramic radiographs of 330 individuals (110 with ns-PRS; 110 with ns-CP and 110 without any malformations) were digitized and evaluated regarding the diagnosis of taurodontism, tooth agenesis, root dilaceration and tooth transposition. Chi-square test was applied to compare the occurrence of dental phenotypes between groups. A P value of less than 0.05 was considered statistically significant. RESULTS: Total prevalence of dental phenotypes was 94.5% of ns-PRS; 54.5% of ns-CP and 59.1% of the control group subjects with a statistically significant difference for the ns-PRS when compared to the other two groups. Two dental phenotypes, taurodontism and dental agenesis were identified with statistically significant higher prevalences in subjects with ns-PRS when compared with the ns-CP group and the control group (p < 0.001). Taurodontism was the most prevalent dental phenotype, with 92.73% in the ns-PRS group, 40.91% for ns-CP and 44.55% in the control group. Tooth agenesis had a prevalence of 22.7% for ns-PRS, 4.5% for ns-CP and no case in the control group. For the prevalence of root dilaceration and tooth transposition, no statistically significant differences were observed between the three groups. CONCLUSIONS: Due to the high frequency of taurodontism in individuals with ns-PRS, we suggested that this novel phenotype would be important in the phenotypic screening of ns-PRS and could be considered as a phenotype associated with ns-PRS.

Non-syndromic tooth agenesis patterns and their association with other dental anomalies: A retrospective study.

OBJECTIVE: This study aimed to investigate the prevalence and the factors associated with non-syndromic tooth agenesis, besides identifying its pattern of occurrence. STUDY DESIGN: Pre-orthodontic exams of 3400 subjects, aged 8-30 years, were selected from a radiographic center in Brazil. Panoramic and periapical radiographs were analyzed to verify the presence of tooth agenesis and other six dental anomalies. Descriptive statistics were calculated using the Tooth Agenesis Code tool and, to evaluate significant associations, a negative binomial regression model was constructed. Besides, unadjusted and adjusted prevalence ratios (PR) were calculated for the bivariate and the multivariate analysis. RESULTS: Prevalence of tooth agenesis was 3.0% (n = 68) and 41 different phenotypic patterns were observed. Teeth most often symmetrically missing were maxillary lateral incisors (13.2%) and mandibular second premolars (8.8%). Females (PR = 3.49, CI 95% = 1.96-6.19) presented more tooth agenesis. Other dental anomalies, such as palatal displacement of maxillary canine and infraocclusion of primary molar were significantly more frequent (p < 0.001) in subjects with agenesis. CONCLUSION: There was a strong relationship between tooth agenesis and gender and the association with other dental anomalies was significant, with the exception of the supernumerary teeth, which seems to be independent.

Oral manifestations and rehabilitation in Fraser syndrome: A case report.

Fraser syndrome (FS) is a rare recessive autosomal genetic disorder characterized by multisystemic malformations typically comprising cryptophthalmos, syndactyly, and renal defects. We report the case of a 16-year-old patient who exhibited facial asymmetry, short roots, hypodontia, and malocclusion. Oral rehabilitation included orthodontics, exodontia, and osseointegrated dental implants to improve the patient's self-esteem and eating function. We suggest short roots and hypodontia assessment in patients with FS.

Incisivo central único de la línea media del maxilar, holoprosencefalia y estenosis congènita del orificio nasal anterior en un recién nacido prematuro: a propósito de un caso / Solitary median maxillary central incisor, holoprosencephaly and congenital nasal pyriform aperture stenosis in a premature infant: case report

El síndrome del incisivo central único de la línea media del maxilar es un trastorno raro que implica anomalías de la línea media, como holoprosencefalia, anomalías de las fosas nasales, fisura palatina, labio leporino, hipotelorismo, microcefalia y panhipopituitarismo. La estenosis congénita del orificio nasal anterior es una causa mortal de dificultad respiratoria neonatal debido al estrechamiento del orificio nasal anterior, y podría confundirse con la atresia de coanas. En este informe, presentamos el caso de un recién nacido con síndrome del incisivo central único de la línea media del maxilar acompañado de otras anomalías, tales como holoprosencefalia, estenosis del orificio nasal anterior, microcefalia y panhipopituitarismo. El cariotipado mostró una deleción heterocigota en el gen SIX3 en la región 2p21, que produjo una forma más grave de holoprosencefalia.

Solitary median maxillary central incisor syndrome is a rare disorder involving midline abnormalities such as holoprosencephaly, nasal cavity anomalies, cleft palate-lip, hypotelorism, microcephaly, and panhypopituitarism. Congenital nasal pyriform aperture stenosis is a lethal cause of neonatal respiratory distress due to narrowing of the pyriform aperture anteriorly and it can be confused with choanal atresia. In this report, we present a newborn infant with solitary median maxillary central incisor syndrome accompanied by other abnormalities including holoprosencephaly, nasal pyriform aperture stenosis, microcephaly and panhypopituitarism. Chromosomal analysis showed heterozygous SIX3 gene deletion at 2p21 region resulting in a more severe form of holoprosencephaly.

Solitary median maxillary central incisor, holoprosencephaly and congenital nasal pyriform aperture stenosis in a premature infant: case report. / Incisivo central único de la línea media del maxilar, holoprosencefalia y estenosis congènita del orificio nasal anterior en un recién nacido prematuro: a propósito de un caso.

Solitary median maxillary central incisor syndrome is a rare disorder involving midline abnormalities such as holoprosencephaly, nasal cavity anomalies, cleft palate-lip, hypotelorism, microcephaly, and panhypopituitarism. Congenital nasal pyriform aperture stenosis is a lethal cause of neonatal respiratory distress due to narrowing of the pyriform aperture anteriorly and it can be confused with choanal atresia. In this report, we present a newborn infant with solitary median maxillary central incisor syndrome accompanied by other abnormalities including holoprosencephaly, nasal pyriform aperture stenosis, microcephaly and panhypopituitarism. Chromosomal analysis showed heterozygous SIX3 gene deletion at 2p21 region resulting in a more severe form of holoprosencephaly.

El síndrome del incisivo central único de la línea media del maxilar es un trastorno raro que implica anomalías de la línea media, como holoprosencefalia, anomalías de las fosas nasales, fisura palatina, labio leporino, hipotelorismo, microcefalia y panhipopituitarismo. La estenosis congénita del orificio nasal anterior es una causa mortal de dificultad respiratoria neonatal debido al estrechamiento del orificio nasal anterior, y podría confundirse con la atresia de coanas. En este informe, presentamos el caso de un recién nacido con síndrome del incisivo central único de la línea media del maxilar acompañado de otras anomalías, tales como holoprosencefalia, estenosis del orificio nasal anterior, microcefalia y panhipopituitarismo. El cariotipado mostró una deleción heterocigota en el gen SIX3 en la región 2p21, que produjo una forma más grave de holoprosencefalia.

Nonsurgical treatment for a severe anterior and lateral open bite and multiple congenitally missing teeth: a case report with 4-year follow-up

ABSTRACT This case report describes the treatment of a severe anterior and lateral open bite combined with multiple congenitally missing teeth. A 10-year-old girl presented with an open gonial angle, absence of lip sealing, and soft tissue pogonion retrusion. She had an open bite of 8.5 mm, agenesis of the upper right and left lateral incisors and the upper left first premolar, and transverse maxillary deficiency. Nonsurgical treatment was planned aiming at controlling the vertical pattern, establishing the correct overbite, and closing the spaces on the upper arch, to provide satisfactory occlusion and facial and dental esthetics.

RESUMO O presente caso clínico descreve o tratamento de uma mordida aberta anterior e lateral associada à ausência congênita de dentes permanentes. Paciente com 10 anos de idade, apresentava ângulo goníaco aberto, ausência de selamento labial passivo e retrusão do pogônio mole. Além disso, foi diagnosticada uma mordida aberta de 8,5 mm, agenesia de incisivos laterais superiores direito e esquerdo e de primeiro pré-molar superior esquerdo, além de deficiência transversa da maxila. O planejamento do caso envolveu um tratamento não cirúrgico, com controle vertical do crescimento, obtenção de correta sobremordida e fechamento dos espaços superiores. O caso foi finalizado com uma boa intercuspidação, contemplando a estética facial e dentária.

"Maxillary lateral incisor partial anodontia sequence": a clinical entity with epigenetic origin

ABSTRACT The relationship between maxillary lateral incisor anodontia and the palatal displacement of unerupted maxillary canines cannot be considered as a multiple tooth abnormality with defined genetic etiology in order to be regarded as a "syndrome". Neither were the involved genes identified and located in the human genome, nor was it presumed on which chromosome the responsible gene would be located. The palatal maxillary canine displacement in cases of partial anodontia of the maxillary lateral incisor is potentially associated with environmental changes caused by its absence in its place of formation and eruption, which would characterize an epigenetic etiology. The lack of the maxillary lateral incisor in the canine region means removing one of the reference guides for the eruptive trajectory of the maxillary canine, which would therefore, not erupt and /or impact on the palate. Consequently, and in sequence, it would lead to malocclusion, maxillary atresia, transposition, prolonged retention of the deciduous canine and resorption in the neighboring teeth. Thus, we can say that we are dealing with a set of anomalies and multiple sequential changes known as sequential development anomalies or, simply, sequence. Once the epigenetics and sequential condition is accepted for this clinical picture, it could be called "Maxillary Lateral Incisor Partial Anodontia Sequence."

RESUMO A relação entre a anodontia parcial do incisivo lateral e o deslocamento palatino do canino superior não irrompido não pode ser considerada uma anomalia dentária múltipla com etiopatogenia genética definida, a ponto de ser considerada como uma "síndrome". Os genes envolvidos sequer foram identificados e localizados no genoma humano, e nem mesmo presumiu-se em qual cromossomo se localizaria o gene responsável. O deslocamento palatino do canino superior em casos de anodontia parcial do incisivo lateral superior está potencialmente associado às mudanças ambientais provocadas pela sua ausência no local de formação e erupção, o que caracterizaria uma etiologia epigenética para essa associação. A falta do incisivo lateral superior na região canina implica em tirar um dos guias referenciais da trajetória eruptiva do canino superior, que ficaria, assim, não irrompido e/ou impactado no palato. Como consequência, e em sequência, promove-se uma má oclusão, atresia maxilar, transposição, retenção prolongada do canino decíduo e reabsorções nos dentes vizinhos. Dessa forma, pode-se afirmar que estamos frente a um conjunto de anomalias e alterações múltiplas sequenciais conhecido como anomalias de desenvolvimento sequencial ou, simplesmente, sequência. Uma vez aceita a condição epigenética e sequencial para esse quadro clínico, ele poderia ser chamado de "Sequência da Anodontia Parcial do Incisivo Lateral Superior".

Agenesis of mandibular second premolar in patient with dental bimaxillary protrusion.

The present study reports the treatment carried out in a patient with mandibular second premolar agenesis associated with early loss of a deciduous second molar, deep overbite, severe overjet and dentoalveolar bimaxillary protrusion, which led to lip incompetence and a convex facial profile. The main objectives of this treatment were: to eliminate the spaces in mandibular arch, correct overbite, as well as eliminate bimaxillary protrusion and lip incompetence, thus leading to a balanced profile. The case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as part of the requirements to obtain the title of BBO diplomate.

Agenesis of mandibular second premolar in patient with dental bimaxillary protrusion

ABSTRACT The present study reports the treatment carried out in a patient with mandibular second premolar agenesis associated with early loss of a deciduous second molar, deep overbite, severe overjet and dentoalveolar bimaxillary protrusion, which led to lip incompetence and a convex facial profile. The main objectives of this treatment were: to eliminate the spaces in mandibular arch, correct overbite, as well as eliminate bimaxillary protrusion and lip incompetence, thus leading to a balanced profile. The case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as part of the requirements to obtain the title of BBO diplomate.

RESUMO O presente caso clínico relata o tratamento de uma paciente com agenesia de segundo pré-molar inferior associada à perda precoce do segundo molar decíduo, sobremordida profunda, sobressaliência exagerada e biprotrusão dentoalveolar, que causavam incompetência labial e perfil facial convexo. Os objetivos do tratamento foram eliminar os espaços presentes na arcada inferior, corrigir a sobremordida, eliminar a biprotrusão e a incompetência labial, harmonizando o perfil. Esse caso foi apresentado ao Board Brasileiro de Ortodontia e Ortopedia Facial (BBO) como parte dos requisitos para obtenção do título de Diplomado pelo BBO.

Second premolar agenesis as a subclinical phenotype of isolated cleft palate.

OBJECTIVE: To compare the prevalence of dental anomalies in patients with isolated cleft palate with or without hypodontia of the second premolar. SETTING AND SAMPLE POPULATION: A total of 653 patients with isolated cleft palate aged 8-12 years were divided into two groups: G1-subjects without hypodontia of second premolar (n = 546) and G2-subjects with hypodontia of at least one-second premolar (n = 107). The control group consisted of 107 non-cleft orthodontic patients. MATERIALS & METHODS: Panoramic and periapical radiographs and dental casts were used to analyze the presence of dental anomalies. Intergroup comparisons were performed using the chi-square test complemented by Proportion test and Bonferroni test. RESULTS: G2 presented higher prevalence of hypodontia of other permanent teeth compared to G1 and control. Ectopic eruption of the maxillary canine and tooth transposition were more frequent in patients with a cleft compared to patients without a cleft, without statistical differences. Deciduous molar infra-occlusion and second premolar disto-angulation were less prevalent in G1 and G2 compared to the control group. G2 showed a higher prevalence of complete cleft palate than G1. CONCLUSION: Patients with cleft palate and second premolar agenesis showed increased prevalence of tooth agenesis and palatally displaced canines.

"Maxillary lateral incisor partial anodontia sequence": a clinical entity with epigenetic origin.

The relationship between maxillary lateral incisor anodontia and the palatal displacement of unerupted maxillary canines cannot be considered as a multiple tooth abnormality with defined genetic etiology in order to be regarded as a "syndrome". Neither were the involved genes identified and located in the human genome, nor was it presumed on which chromosome the responsible gene would be located. The palatal maxillary canine displacement in cases of partial anodontia of the maxillary lateral incisor is potentially associated with environmental changes caused by its absence in its place of formation and eruption, which would characterize an epigenetic etiology. The lack of the maxillary lateral incisor in the canine region means removing one of the reference guides for the eruptive trajectory of the maxillary canine, which would therefore, not erupt and /or impact on the palate. Consequently, and in sequence, it would lead to malocclusion, maxillary atresia, transposition, prolonged retention of the deciduous canine and resorption in the neighboring teeth. Thus, we can say that we are dealing with a set of anomalies and multiple sequential changes known as sequential development anomalies or, simply, sequence. Once the epigenetics and sequential condition is accepted for this clinical picture, it could be called "Maxillary Lateral Incisor Partial Anodontia Sequence."