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1.
Niger J Clin Pract ; 22(8): 1157-1162, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31417061

RESUMO

Background: The aims of this study are to present sociodemographic and familial characteristics, clinical and systemic findings, dental treatment needs, and concomitant dental anomalies in patients with amelogenesis imperfecta (AI) and to evaluate time-varying conditions in these long-term follow-up patients. Materials and Methods: Records of patients with AI who were examined in the Department of Pediatric Dentistry between 1999 and 2017 were reviewed. Information about sociodemographic characteristics, history of AI and consanguinity in family, systemic conditions, reasons for referral to the clinic, oral hygiene habits and gingival health, occlusion findings, and performed treatments were gathered. Dental anomalies in radiographs were also evaluated. Baseline and final situations of the patients were assessed. Statistical analyses were performed. Results: Of 75 patients aged 3-15 years with follow-ups up to 12 years, 34 had AI in their families and 15 were born from consanguineous marriages. Nephrocalcinosis has been observed in 5 patients. Main reasons for referral to the clinic were related to esthetic and hypersensitivity concerns. Twenty-two patients had gingivitis, and during follow-up process, gingival problems could not be completely prevented due to poor oral hygiene habits. Vertical dimension loss, open-bite, and cross-bite were seen in 16, 15, and 10 patients, respectively. Of the patients, 63% experienced restorative, 33% stainless steel crown, 17% endodontic, 8% prosthetic treatments, and 24% had retreatment needs. Concomitant dental anomalies were dens invaginatus, taurodontism, ectopic eruption, delayed eruption, hypodontia, and pulpal calcification. Conclusion: Early diagnosis and interventions considering the time-varying conditions with long-term follow-ups provide significant improvements in clinical maintenance of patients with AI.


Assuntos
Amelogênese Imperfeita/diagnóstico por imagem , Amelogênese Imperfeita/terapia , Esmalte Dentário/anormalidades , Reabilitação Bucal/métodos , Radiografia Panorâmica , Adolescente , Amelogênese Imperfeita/genética , Criança , Pré-Escolar , Cárie Dentária/terapia , Sensibilidade da Dentina/epidemiologia , Sensibilidade da Dentina/terapia , Estética Dentária , Feminino , Gengivite/epidemiologia , Humanos , Masculino , Má Oclusão , Nefrocalcinose/epidemiologia , Nefrocalcinose/terapia , Índice de Higiene Oral , Aço Inoxidável
2.
J Appl Oral Sci ; 27: e20180359, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30970114

RESUMO

Amelogenesis imperfecta (AI) is a group of enamel development disorders that alter the structure and chemical composition of the tissue. There is great variability in the clinical presentation; according to Witkop, AI can be categorized into 14 subtypes, which makes its diagnosis extremely complex. OBJECTIVE: This study aimed to describe and determine the frequency of clinical and radiographic features and inheritance patterns found in 41 Chilean families diagnosed with diverse types of AI. MATERIAL AND METHODS: We analyzed the clinical records, photographs, pedigrees and radiographs of 121 individuals recruited between 2003 and 2016. All of the information was included in a database that was analyzed using the application Stata 14. RESULTS: The 72 affected individuals had average age of 16 years, and no sex association with the presence of AI was found. The most frequent clinical subtypes were as follows: 43% hypomature, 25% hypoplastic, 21% hypomature/hypoplastic, 7% hypocalcified and 4% hypocalcified/hypoplastic. The number of severely affected teeth was 22, which occurred in the patients with hypocalcified and hypocalcified/hypoplasic AI who presented the highest number of damaged teeth. Caries and periodontal disease were found in 47 and 32% of the patients, respectively. Malocclusions were observed in 43% of the individuals with AI, with open bite being the most frequent. Radiographically, the thickness of the enamel decreased in 51% of the patients, and 80% showed decreased radiopacity of the enamel compared to that of dentin. Autosomal dominant inheritance pattern was found in 37% of the families with hypoplastic AI, and autosomal recessive pattern was present in 56% of the other clinical subtypes, but more frequently in those affected with hypomature and hypocalcified AI. CONCLUSION: Of the five clinical subtypes, autosomal recessive hypomature, autosomal dominant hypoplastic and autosomal recessive hypomature/hypoplastic AI were the most prevalent subtypes in this group.


Assuntos
Amelogênese Imperfeita/diagnóstico por imagem , Amelogênese Imperfeita/genética , Genealogia e Heráldica , Padrões de Herança , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Amelogênese Imperfeita/epidemiologia , Amelogênese Imperfeita/patologia , Criança , Pré-Escolar , Chile/epidemiologia , Esmalte Dentário/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Distribuição por Sexo , Estatísticas não Paramétricas , Adulto Jovem
3.
J Contemp Dent Pract ; 19(5): 599-604, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29807973

RESUMO

BACKGROUND: Amelogenesis imperfecta is a heterogeneous group of hereditary disorders that affect the enamel formation of the primary and permanent dentitions while the remaining tooth structure is normal. Appropriate patient care is necessary to prevent adverse effects on dental oral health, dental disfigurement, and psychological well-being. AIM: This clinical report presents a 27-year-old Chinese male with amelogenesis imperfecta (AI) and his restorative management. CASE REPORT: This clinical report presents a 27-year-old Chinese male with AI and his restorative management. Extraoral examination showed a skeletal class III profile and increased lower facial proportion. Intraorally, all the permanent dentition was hypoplastic with noticeable tooth surface loss and a yellow-brown appearance. This was complicated with a mild maloc-clusion and food packing on his posterior teeth. The patient wanted to improve his appearance and masticatory efficiency. Orthodontic treatment was performed to treat the mild malocclu-sion and create physiological interproximal spacing to minimize tooth preparation and facilitate oral hygiene. CONCLUSION: This report demonstrates how a multidisciplinary approach for the management of AI can achieve a predictable, functional, and esthetic outcome. Orthodontic treatment facilitated a conservative prosthodontic treatment outcome by selectively increasing interproximal space, minimizing tooth preparation, correcting posterior bilateral cross-bite, as well as an anterior reverse overjet and derotation of the canines. CLINICAL SIGNIFICANCE: This case report demonstrates the effective restoration of AI using a multidisciplinary approach to overcome crowding using a relatively conservative approach.


Assuntos
Amelogênese Imperfeita/reabilitação , Amelogênese Imperfeita/terapia , Ortodontia/métodos , Adulto , Amelogênese Imperfeita/diagnóstico por imagem , Cerâmica , Coroas , Materiais Dentários , Porcelana Dentária , Facetas Dentárias , Humanos , Comunicação Interdisciplinar , Masculino
4.
Int J Prosthodont ; 31(1): 31­34, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29166418

RESUMO

Dental rehabilitation of acute cases of enamel renal syndrome is challenging due to the absence of clinical reports. In the present case history report, examination of an 18-year-old patient revealed a complete lack of permanent teeth, as well as irregular and swollen bone and gingival morphology. Radiographs showed multiple impacted teeth in both arches. Creating a 1.5- to 2-cm interarch space was necessary for setting complete dentures. The ideal occlusal plane was chosen by combining two techniques (cephalometric radiograph and modification of the mandibular occlusal rim according to anatomical guidelines). Extraction of impacted teeth and recontouring of the alveolar process were performed simultaneously. The mandibular denture was connected through Locator abutments to two symphyseal implants. This pioneering clinical report will provide guidance to practitioners in the surgical intervention of patients with FAM20A (family with sequence similarities 20 A) gene mutations.


Assuntos
Amelogênese Imperfeita/reabilitação , Prótese Total , Reabilitação Bucal/métodos , Nefrocalcinose/reabilitação , Adolescente , Amelogênese Imperfeita/diagnóstico por imagem , Humanos , Masculino , Nefrocalcinose/diagnóstico por imagem , Fenótipo
5.
Oral Dis ; 24(3): 384-392, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28771955

RESUMO

OBJECTIVE: To explore the mineral features of dentin and cementum in hypoplastic Amelogenesis imperfecta AI teeth. MATERIALS AND METHODS: Forty-four (44) teeth cleaned and free of caries were used: 20 control and 24 affected by hypoplastic amelogenesis imperfecta. Thirty-two teeth were studied by pQCT, cut in sections, and analyzed under microradiography, polarized light microscopy, and confocal Raman spectroscopy. Eight teeth were observed under scanning electron microscope. Four teeth were used for an X-ray diffraction. The mineral density data were analyzed statistically with the Mann-Whitney U test, using GraphPad InStat software. RESULTS: Both coronal dentin and radicular dentin were less mineralized in AI teeth when compared to control (respectively 6.2% and 6.8%; p < .001). Root dentinal walls were thin and irregular, while the cellular cementum layers were thick, reaching sometimes the cervical region of the tooth. Regular dentinal tubules and sclerotic dentin areas were noticed. Partially tubular or cellular dysplastic dentin and hyper-, normo-, or hypomineralized areas were noticed in the inter-radicular areas of hypoplastic AI teeth. The main mineral component was carbonate hydroxyapatite as explored by Raman spectroscopy and X-ray diffraction. CONCLUSIONS: Dentin and cementum in hypoplastic AI teeth are (i) hypomineralized, (ii) constituted of carbonate hydroxyapatite, and (iii) of non-homogenous structure.


Assuntos
Amelogênese Imperfeita/diagnóstico por imagem , Cemento Dentário/diagnóstico por imagem , Dentina/diagnóstico por imagem , Minerais/análise , Adolescente , Adulto , Cemento Dentário/química , Dentina/química , Humanos , Microrradiografia , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Análise Espectral Raman , Tomografia Computadorizada por Raios X/métodos , Dente/química , Dente/diagnóstico por imagem , Difração de Raios X , Adulto Jovem
6.
Cir. plást. ibero-latinoam ; 43(4): 395-400, oct.-dic. 2017. graf, tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-170455

RESUMO

Introducción y Objetivo. El síndrome de Moebius es un trastorno congénito poco frecuente con prevalencia menor del 0.05%, caracterizado por parálisis facial congénita asociada a ausencia de abducción de los ojos por alteraciones del VI y VII nervios craneales, ya sea simétrica o asimétrica. La etiopatogenia cuenta con diferentes hipótesis: genética, vascular y teratógena. Existen pocos reportes en la literatura, y en especial en la latinoamericana, que describan las características clínicas y genéticas de estos pacientes. El presente estudio es el resultado del desarrollo de un equipo multidisciplinario en nuestro centro hospitalario para la descripción del espectro completo de la patología y así poder ofrecer los mejores tratamientos para cada uno de nuestros pacientes. Material y Método. Analizamos 115 pacientes con diagnóstico de síndrome de Moebius en sus 3 presentaciones: Moebius clásico, Moebius incompleto o Moebiuslike. Todos fueron sometidos a exploración física completa por un equipo multidisciplinario formado por ortopedistas, oftalmólogos, otorrinolaringólogos, ortodoncistas, neurólogos, pediatras, genetistas y cirujanos plásticos. Realizamos cariotipos a todos los pacientes para identificar anormalidades estructurales cromosómicas y enviamos muestras al Instituto Nacional de Medicina Genómica (INMeGen) para análisis molecular de cada paciente e identificación de posibles genes involucrados. Resultados. Un total de 52 pacientes (45%) fueron varones y 63 (55%) mujeres. Las manifestaciones clínicas fueron parálisis facial unilateral o bilateral con involucro de la abducción de los ojos en el 100%, asociada con estrabismo en el 62.6%, pie equino varo en el 46.1%, sindactilia simple 15.7%, paladar hendido 17.4%, micrognatia 17.4%, y síndrome de Poland 9.6%, entre otras manifestaciones. El análisis citogenético reportó 114 cariotipos de características estructurales normales y 1 solo caso de translocación recíproca balanceada entre el cromosoma 4 y 10. Dieciséis casos se asociaron a consumo materno de misoprostol en el primer trimestre del embarazo. El análisis molecular no se pudo concretar debido a falta de recursos materiales del INMeGen. Conclusiones. Hasta la fecha, y hasta donde hemos podido comprobar, esta es la cohorte de pacientes con síndrome de Moebius más grande reportada a nivel mundial en un solo centro hospitalario. La variabilidad de las presentaciones clínicas justifica el manejo por un equipo multidisciplinario tanto para el paciente como para los familiares. Este estudio abre las puertas para un campo de investigación mayor que nos pueda llevar a entender mejor la fisiopatología, intentar estableces causalidad y por lo tanto poder ofrecer mejores tratamientos, integrales y reproducibles (AU)


Background and Objective. Möbius syndrome is a rare congenital disease characterized by facial paralysis associated with an absence of abduction of the eyes for abnormalities in VI and VII cranial nerves. The pathogenesis has different hypothesis that include genetic, vascular and teratogenic causes. There are few reports in the literature and especially in Latin America to describe the clinical and genetic characteristics of these patients. The current study is the result of a multidisciplinary team developed in our center to describe the wide spectrum of the disease and offer the best treatment options to each of our patients. Methods. We analyzed 115 patients with the diagnosis of Möbius syndrome in its 3 presentations. All patients underwent a complete clinical examination by a multidisciplinary team formed by orthopedist, ophthalmologist, otolaryngologist, orthodontist, neurologist, plastic surgeon, pediatrician and geneticist. They underwent CTG banded karyotype to identify structural chromosome abnormalities. Results. Fifty two patients (45%) patients were male and 63 (55%) female. Clinical manifestations were found with unilateral or bilateral facial paralysis with VI nerve involvement in 100% of patients, associated with strabismus in 62.6%, 46.1% clubfoot, simple syndactyly 15.7%, 17.4% cleft palate, micrognathia 17.4%, Poland syndrome 9.6%, among others. Cytogenetic analysis showed normal karyotype in 114 patients and a reciprocal translocation between chromosome 4 and 10 in 1 patient. Sixteen cases of reported intake of misoprostol during the first trimester. Conclusions. As far as we know, this study is the largest global cohort reported in a single hospital of patients with Möbius syndrome. Variability of the clinical presentation justifies the management of these patients is a multidisciplinary team. This study opens the door for new studies that allow us to understand the pathophysiology of this disease and its response to different treatments (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Citogenética , Paralisia Facial/diagnóstico por imagem , Paralisia Facial/cirurgia , Paralisia Facial/congênito , Síndrome de Möbius/diagnóstico por imagem , Síndrome de Möbius/cirurgia , Nervo Abducente/diagnóstico por imagem , Paralisia Facial/genética , Estrabismo/complicações , Pé Torto Equinovaro/complicações , Sindactilia/complicações , Fissura Palatina/complicações , Nervo Abducente/anormalidades , Nervo Abducente/citologia , Eletromiografia/métodos , Amelogênese Imperfeita/complicações , Amelogênese Imperfeita/diagnóstico por imagem
8.
Oral Surg Oral Med Oral Pathol Oral Radiol ; 123(2): 229-234.e2, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28086997

RESUMO

Enamel-renal syndrome (OMIM #204690) is an uncommon disorder characterized by amelogenesis imperfecta and nephrocalcinosis and is caused by mutations in FAM20 A. We report 2 patients with enamel-renal syndrome who exhibited the typical features of this syndrome and a homozygous nonsense mutation in the FAM20 A gene (c.406 C>T), genetically confirming the diagnosis. They also exhibited 2 undescribed clinical features, hypertrichosis and hearing loss. Alterations in genes frequently associated with nonsyndromic hearing loss in the Brazilian population, including connexin 26 (GJB2), connexin 30 (GJB6) and mitochondrial 12 S rRNA (m.A1555 G mutation), were not found. These results suggest a putative function of FAM20 A in the development of the inner ear and in the formation of hair. The presence of nephrocalcinosis is a risk factor for renal impairment, and it is important to perform regular renal monitoring in order to avoid renal failure.


Assuntos
Amelogênese Imperfeita/genética , Proteínas do Esmalte Dentário/genética , Perda Auditiva/genética , Mutação , Nefrocalcinose/genética , Amelogênese Imperfeita/diagnóstico por imagem , Criança , Consanguinidade , Feminino , Humanos , Hipertricose/genética , Nefrocalcinose/diagnóstico por imagem , Linhagem , Fenótipo , Radiografia Panorâmica
9.
Arch Oral Biol ; 76: 61-65, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28130977

RESUMO

OBJECTIVES: Amelogenesis imperfecta (AI) is a hereditary genetic defect affecting tooth enamel. AI is heterogeneous in clinical phenotype as well as in genetic etiology. To date, more than 10 genes have been associated with the etiology of AI. Amelogenin is the most abundant enamel matrix protein, most of which is encoded by the amelogenin gene in the X-chromosome (AMELX). More than 16 alternative splicing transcripts have been identified in the murine Amelx gene. The purpose of this study was to identify the genetic cause of an AI family. MATERIALS AND METHODS: We recruited a family with hypoplastic AI and performed mutational analysis on the candidate gene based on the clinical phenotype. RESULTS: Mutational analysis revealed a missense mutation in exon 6 (NM_182680.1; c.242C > T), which changes a sequence in a highly conserved amino acid (NP_872621.1; p.Pro81Leu). Furthermore, a splicing assay using a minigene displayed that the mutation changed the mRNA splicing repertory. CONCLUSIONS: In this study, we identified a novel AMELX missense mutation causing hypoplastic AI, and this mutation also resulted in altered mRNA splicing. These results will not only expand the mutation spectrum causing AI but also broaden our understanding of the biological mechanism of enamel formation.


Assuntos
Amelogênese Imperfeita/genética , Amelogenina/genética , Mutação de Sentido Incorreto , Amelogênese Imperfeita/diagnóstico por imagem , Criança , Análise Mutacional de DNA , Humanos , Masculino , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Radiografia Panorâmica , República da Coreia
10.
Sci Rep ; 6: 25364, 2016 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-27146352

RESUMO

Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2(f/f);Bmp4(f/f)ameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling.


Assuntos
Amelogênese Imperfeita/diagnóstico por imagem , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 4/genética , Regulação para Baixo , Calicreínas/genética , Metaloproteinase 20 da Matriz/genética , Amelogênese Imperfeita/genética , Animais , Modelos Animais de Doenças , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Deleção de Genes , Técnicas de Inativação de Genes , Humanos , Calicreínas/metabolismo , Metaloproteinase 20 da Matriz/metabolismo , Camundongos , Microscopia de Força Atômica , Radiografia , Transdução de Sinais
11.
J Prosthet Dent ; 116(3): 309-13, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27112411

RESUMO

Amelogenesis imperfecta is a hereditary disease affecting the structural development of tooth substance. This clinical report describes a 1-visit chairside treatment of an 8-year-old patient with amelogenesis imperfecta, using computer-aided design and computer-aided manufacturing (CAD-CAM) technology. Intraoral scanning was performed using the Cerec Omnicam. Thirteen resin nanoceramic crowns (Lava Ultimate) were fabricated chairside by using a Cerec MCXL milling unit and seated adhesively. The patient's treatment included establishing a new occlusal vertical dimension and new centric relationship. Reevaluation after 6 months showed a stable situation.


Assuntos
Amelogênese Imperfeita/cirurgia , Projeto Auxiliado por Computador , Coroas , Planejamento de Prótese Dentária/métodos , Amelogênese Imperfeita/diagnóstico por imagem , Cerâmica/uso terapêutico , Criança , Humanos , Nanoestruturas/uso terapêutico , Radiografia Dentária , Dimensão Vertical
12.
Oral Dis ; 22(4): 297-302, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26762616

RESUMO

OBJECTIVE: To identify the molecular genetic aetiology of a family with autosomal dominant amelogenesis imperfecta (AI). SUBJECTS AND METHODS: DNA samples were collected from a six-generation family, and the candidate gene approach was used to screen for the enamelin (ENAM) gene. Whole-exome sequencing and linkage analysis with SNP array data identified linked regions, and candidate gene screening was performed. RESULTS: Mutational analysis revealed a mutation (c.561_562delCT and p.Tyr188Glnfs*13) in the DLX3 gene. After finding a recurrent DLX3 mutation, the clinical phenotype of the family members was re-examined. The proband's mother had pulp elongation in the third molars. The proband had not hair phenotype, but her cousin had curly hair at birth. CONCLUSIONS: In this study, we identified a recurrent 2-bp deletional DLX3 mutation in a new family. The clinical phenotype was the mildest one associated with the DLX3 mutations. These results will advance the understanding of the functional role of DLX3 in developmental processes.


Assuntos
Amelogênese Imperfeita/genética , Sequência de Bases , Proteínas de Homeodomínio/genética , Deleção de Sequência , Fatores de Transcrição/genética , Adulto , Amelogênese Imperfeita/diagnóstico por imagem , Criança , Análise Mutacional de DNA , Exoma , Feminino , Humanos , Masculino , Linhagem , Fenótipo , Radiografia Dentária
13.
Quintessence Int ; 46(10): 843-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26345104

RESUMO

The complete dental rehabilitation of patients with a vertical dimension loss (VDL) caused by structural enamel deficits associated with amelogenesis imperfecta (AI) represents a difficult challenge for restorative teams. Accurate analysis and treatment planning that includes esthetic and functional evaluations and adequate material selection are important prerequisites for successful results. Long-term provisional restorations play an important role in exploring and elucidating the patients' esthetic demands and functional needs. Restorative treatment options can vary from requiring only oral hygiene instructions to extensive dental restorations that include composite fillings, ceramic veneers, metal-ceramic, or all-ceramic crowns. This case report describes a full-mouth rehabilitation of a patient with amelogenesis imperfecta including the case planning, bite replacement, preparation, and restoration setting steps with an experimental CAD/CAM polymer and porcelain veneers.


Assuntos
Amelogênese Imperfeita/terapia , Projeto Auxiliado por Computador , Porcelana Dentária/química , Facetas Dentárias , Reabilitação Bucal/métodos , Adulto , Amelogênese Imperfeita/diagnóstico por imagem , Planejamento de Prótese Dentária , Estética Dentária , Feminino , Humanos , Radiografia Panorâmica , Dimensão Vertical
14.
J Dent Res ; 94(8): 1063-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26124219

RESUMO

In order to achieve highly mineralized tooth enamel, enamel proteinases serve the important function of removing the remaining organic matrix in the mineralization and maturation of the enamel matrix. Mutations in the kallikrein 4 (KLK4), enamelysin (MMP20), and WDR72 genes have been identified as causing hypomaturation enamel defects in an autosomal-recessive hereditary pattern. In this report, 2 consanguineous families with a hypomaturation-type enamel defect were recruited, and mutational analysis was performed to determine the molecular genetic etiology of the disease. Whole exome sequencing and autozygosity mapping identified novel homozygous mutations in the KLK4 (c.620_621delCT, p.Ser207Trpfs*38) and MMP20 (c.1054G>A, p.Glu352Lys) genes. Further analysis on the effect of the mutations on the translation, secretion, and function of KLK4 and MMP20 revealed that mutant KLK4 was degraded intracellularly and became inactive while mutant MMP20 was expressed at a normal level but secreted only minimally with proteolytic function.


Assuntos
Amelogênese Imperfeita/genética , Calicreínas/genética , Metaloproteinase 20 da Matriz/genética , Mutação , Amelogênese Imperfeita/diagnóstico por imagem , Western Blotting , Criança , Consanguinidade , Feminino , Genótipo , Homozigoto , Humanos , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Radiografia Panorâmica , Análise de Sequência de DNA
15.
Hum Mol Genet ; 24(11): 3038-49, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25669657

RESUMO

Inherited dental malformations constitute a clinically and genetically heterogeneous group of disorders. Here, we report on four families, three of them consanguineous, with an identical phenotype, characterized by significant short stature with brachyolmia and hypoplastic amelogenesis imperfecta (AI) with almost absent enamel. This phenotype was first described in 1996 by Verloes et al. as an autosomal recessive form of brachyolmia associated with AI. Whole-exome sequencing resulted in the identification of recessive hypomorphic mutations including deletion, nonsense and splice mutations, in the LTBP3 gene, which is involved in the TGF-beta signaling pathway. We further investigated gene expression during mouse development and tooth formation. Differentiated ameloblasts synthesizing enamel matrix proteins and odontoblasts expressed the gene. Study of an available knockout mouse model showed that the mutant mice displayed very thin to absent enamel in both incisors and molars, hereby recapitulating the AI phenotype in the human disorder.


Assuntos
Amelogênese Imperfeita/genética , Proteínas de Ligação a TGF-beta Latente/genética , Osteocondrodisplasias/genética , Adolescente , Amelogênese Imperfeita/diagnóstico por imagem , Animais , Sequência de Bases , Criança , Consanguinidade , Análise Mutacional de DNA , Feminino , Mutação da Fase de Leitura , Estudos de Associação Genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação de Sentido Incorreto , Osteocondrodisplasias/diagnóstico por imagem , Linhagem , Radiografia , Deleção de Sequência
16.
Oral Dis ; 21(4): 456-61, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25431241

RESUMO

OBJECTIVE: Hereditary defects in tooth enamel formation, amelogenesis imperfecta (AI), can be non-syndromic or syndromic phenotype. Integrins are signaling proteins that mediate cell-cell and cell-extracellular matrix communication, and their involvement in tooth development is well known. The purposes of this study were to identify genetic cause of an AI family and molecular pathogenesis underlying defective enamel formation. MATERIALS AND METHODS: We recruited a Turkish family with isolated AI and performed mutational analyses to clarify the underlying molecular genetic etiology. RESULTS: Autozygosity mapping and exome sequencing identified a novel homozygous ITGB6 transversion mutation in exon 4 (c.517G>C, p.Gly173Arg). The glycine at this position in the middle of the ßI-domain is conserved among a wide range of vertebrate orthologs and human paralogs. Clinically, the enamel was generally thin and pitted with pigmentation. Thicker enamel was noted at the cervical area of the molars. CONCLUSIONS: In this study, we identified a novel homozygous ITGB6 mutation causing isolated AI, and this advances the understanding of normal and pathologic enamel development.


Assuntos
Amelogênese Imperfeita/etiologia , Amelogênese Imperfeita/genética , Cadeias beta de Integrinas/genética , Mutação , Amelogênese/genética , Amelogênese Imperfeita/sangue , Amelogênese Imperfeita/diagnóstico por imagem , Criança , Análise Mutacional de DNA , Éxons , Feminino , Humanos , Dente Molar/patologia , Linhagem , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Turquia
17.
Neuro Endocrinol Lett ; 35(5): 347-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25275257

RESUMO

Amelogenesis imperfecta (AI) is an overarching term for a group of rare inherited disorders of hard tooth tissues. It is characterized by various defects in proper enamel formation. AI is a severe disorder that affects both the aesthetics and function of the dentition, with affected teeth increasingly suffering from dental caries. Therefore, early diagnosis and lifelong stomatological interventions are important. Due to the complex nature of AI family history, stomatological, radiographic, and molecular genetic examinations should be part of the diagnostic portfolio. Additionally, we utilized new visualization methods for the assessment of teeth demineralization. We present a case report of two affected Czech sisters (6 and 8 years old) with clinically defined AI. These are the first Czech cases in which comprehensive clinical and genetic analysis had been carried out and reflect the complex clinical nature, positive treatment options, and limitations of candidate-gene molecular genetic testing.


Assuntos
Amelogênese Imperfeita/genética , Amelogênese Imperfeita/patologia , Esmalte Dentário/anormalidades , Amelogênese Imperfeita/diagnóstico por imagem , Criança , República Tcheca , Esmalte Dentário/diagnóstico por imagem , Esmalte Dentário/ultraestrutura , Saúde da Família , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Linhagem , Radiografia , Irmãos
18.
Pediatr Dent ; 35(4): 337-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23930633

RESUMO

PURPOSE: The purpose of this study was to assess restorative treatment outcomes in the mixed dentition of amelogenesis imperfecta (AI) patients and determine the postrehabilitation oral health status and satisfaction of the patients. METHODS: Clinical and radiographic examinations were performed on eight AI patients, who had 74 restorations placed in permanent incisors and molars, to allow evaluation of the integrity of the restorations and periodontal status post-treatment. Subjects completed a survey regarding esthetics, function, and sensitivity. RESULTS: Among the 74 restorations evaluated, seven were lost; of the remaining restorations, 31 were posterior, and 36 were anterior. Ten were rated clinically unacceptable. Teeth with stainless steel crowns had a moderate gingival index (mean=2.3) and plaque index (mean=2.0) scores. Widening of the periodontal ligament and pulp canal obliteration were common radiographic findings. Subject's recall of satisfaction regarding esthetics (P=.002) and sensitivity (brushing-P=.03; eating-P=.01) showed a statically significant difference before and after treatment. CONCLUSIONS: During mixed dentition, teeth with amelogenesis imperfecta may be restored with conventional treatment modalities. Direct restorations should be considered "interim" with multiple repairs anticipated. Post-treatment, gingival inflammation and plaque accumulation were observed. Subjects were satisfied with their appearance and reported a decrease of hypersensitivity.


Assuntos
Amelogênese Imperfeita , Restauração Dentária Permanente/métodos , Incisivo/patologia , Dente Molar/patologia , Satisfação do Paciente , Adolescente , Amelogênese Imperfeita/diagnóstico por imagem , Amelogênese Imperfeita/reabilitação , Amelogênese Imperfeita/terapia , Criança , Coleta de Dados , Dentição Mista , Estética Dentária , Feminino , Humanos , Masculino , Radiografia , Resultado do Tratamento
19.
BMJ Case Rep ; 20132013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23709541

RESUMO

A 12-year-old patient presented with a severe delay of eruption in permanent maxillary and mandibular incisors. On examination, there was over-retained primary teeth and delayed eruption of permanent teeth. Retained primary teeth showed light yellow discolouration whereas permanent teeth were distinct yellow with thin or little enamel. Subsequent imaging revealed all the premolars except maxillary left first premolar showed signs of intra-alveolar coronal resorption, nephrocalcinosis with bilateral multiple calculi and small papillary tip calcifications, marked increase in alkaline phosphatase. Subsequent dental treatment for restoring the functional and aesthetic requirement followed by appropriate treatment for renal problem was undertaken.


Assuntos
Amelogênese Imperfeita/complicações , Restauração Dentária Permanente , Nefrocalcinose/complicações , Amelogênese Imperfeita/diagnóstico por imagem , Amelogênese Imperfeita/terapia , Criança , Diagnóstico Diferencial , Humanos , Cariotipagem , Radiografia , Resultado do Tratamento
20.
J Indian Soc Pedod Prev Dent ; 30(2): 169-72, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22918105

RESUMO

Enamel renal syndrome is a very rare disorder associating amelogenesis imperfecta with nephrocalcinosis. It is known by various synonyms such as amelogenesis imperfecta nephrocalcinosis syndrome, MacGibbon syndrome, Lubinsky syndrome, and Lubinsky-MacGibbon syndrome. It is characterized by enamel agenesis and medullary nephrocalcinosis. This paper describes enamel renal syndrome in a female patient born in a consanguineous family.


Assuntos
Amelogênese Imperfeita/patologia , Nefrocalcinose/patologia , Amelogênese Imperfeita/complicações , Amelogênese Imperfeita/diagnóstico por imagem , Amelogênese Imperfeita/urina , Criança , Consanguinidade , Calcificações da Polpa Dentária/etiologia , Feminino , Humanos , Nefrocalcinose/complicações , Nefrocalcinose/diagnóstico por imagem , Nefrocalcinose/urina , Mordida Aberta/etiologia , Síndrome , Dente não Erupcionado/etiologia , Ultrassonografia
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