Enfoque de Tratamiento de una Adolescente con Amelogénesis Imperfecta / Treatment Approach for an Adolescent with Amelogenesis Imperfecta

La amelogénesis imperfecta (AI) es un grupo de tras-tornos hereditarios, clínica y etiológicamente hete-rogéneos, derivados de mutaciones genéticas, que se caracterizan por anomalías cualitativas y cuanti-tativas del desarrollo del esmalte, pudiendo afectar la dentición primaria y/o permanente. El tratamiento del paciente con AI es complejo y multidiscliplinario; supone un desafío para el odontólogo, ya que por lo general están involucradas todas las piezas dentarias y afecta no solo la salud buco dental sino el aspecto emocional y psicológico de los pacientes. Con el obje-tivo de describir el tratamiento integral y rehabilita-dor realizado en una paciente con diagnóstico de AI tipo III, se reporta el caso de un adolescente de sexo femenino de 13 años, que concurrió en demanda de atención a la Cátedra de Odontología Integral Niños de la Facultad de Odontología de la Universidad de Buenos Aires (FOUBA), cuyo motivo de consulta fue la apariencia estética y la hipersensibilidad de sus pie-zas dentarias. Durante el examen clínico intraoral, se observó que todas las piezas dentarias presentaban un esmalte rugoso, blando, con irregularidades y una coloración amarronada, compatible con diagnóstico de Amelogénesis Imperfecta tipo III hipomineralizada. Conclusión: El tratamiento rehabilitador de la AI en los pacientes en crecimiento y desarrollo estará diri-gido a intervenir de manera integral y temprana para resolver la apariencia estética y funcional, evitar las repercusiones sociales y emocionales, y acompañar a los pacientes y sus familias (AU)

Amelogenesis imperfecta (AI) is a group of clinically and etiologically heterogeneous hereditary disorders, derived from genetic mutations, characterized by qualitative and quantitative anomalies of enamel development, which can affect primary and/or permanent dentition. The treatment of patients with AI is complex and multidisciplinary, it is a challenge for the dentist, since in general all the teeth are involved and it affects not only oral health but also the emotional and psychological aspect of the patients. Objective: To describe the comprehensive and rehabilitative treatment carried out in an adolescent patient with a diagnosis of type III AI. Case report: The case of a 13-year-old female patient, who required dental attention at the Department of Dentistry for Children of the School of Dentistry of the University of Buenos Aires, whose reason for consultation was esthetic appearance and hypersensitivity of her teeth. In the intraoral clinical examination, it was observed that all the teeth had rough, soft enamel, with irregularities and a brownish color, compatible with the diagnosis of type III hypomineralized Amelogenesis Imperfecta. Conclusion: Rehabilitative treatment of AI in growing and developing patients will be aimed at early and comprehensive intervention to resolve esthetic and functional appearance, avoid social and emotional repercussions and accompany patients and their families (AU)

Phenotype and Variant Spectrum in the LAMB3 Form of Amelogenesis Imperfecta.

Amelogenesis imperfecta (AI) is a heterogeneous group of inherited disorders characterized by abnormal formation of dental enamel, either in isolation or as part of a syndrome. Heterozygous variants in laminin subunit beta 3 ( LAMB3) cause AI with dominant inheritance in the absence of other cosegregating clinical features. In contrast, biallelic loss-of-function variants in LAMB3 cause recessive junctional epidermolysis bullosa, characterized by life-threatening skin fragility. We identified 2 families segregating autosomal dominant AI with variable degrees of a distinctive hypoplastic phenotype due to pathogenic variants in LAMB3. Whole exome sequencing revealed a nonsense variant (c.3340G>T, p.E1114*) within the final exon in family 1, while Sanger sequencing in family 2 revealed a variant (c.3383-1G>A) in the canonical splice acceptor site of the final exon. Analysis of cDNA from family 2 revealed retention of the final intron leading to a premature termination codon. Two unerupted third molar teeth from individual IV:5 in family 2 were subject to computerized tomography and scanning electron microscopy. LAMB3 molar teeth have a multitude of cusps versus matched controls. LAMB3 enamel was well mineralized but pitted. The architecture of the initially secreted enamel was abnormal, with cervical enamel appearing much less severely affected than coronal enamel. This study further defines the variations in phenotype-genotype correlation for AI due to variants in LAMB3, underlines the clustering of nonsense and frameshift variants causing AI in the absence of junctional epidermolysis bullosa, and highlights the shared AI phenotype arising from variants in genes coding for hemidesmosome proteins.

A practical method for use in epidemiological studies on enamel hypomineralisation.

With the development of the European Academy of Paediatric Dentistry (EAPD) judgment criteria, there has been increasing interest worldwide in investigation of the prevalence of demarcated opacities in tooth enamel substance, known as molar-incisor hypomineralisation (MIH). However, the lack of a standardised system for the purpose of recording MIH data in epidemiological surveys has contributed greatly to the wide variations in the reported prevalence between studies. The present publication describes the rationale, development, and content of a scoring method for MIH diagnosis in epidemiological studies as well as clinic- and hospital-based studies. The proposed grading method allows separate classification of demarcated hypomineralisation lesions and other enamel defects identical to MIH. It yields an informative description of the severity of MIH-affected teeth in terms of the stage of visible enamel destruction and the area of tooth surface affected (i.e. lesion clinical status and extent, respectively). In order to preserve the maximum amount of information from a clinical examination consistent with the need to permit direct comparisons between prevalence studies, two forms of the charting are proposed, a short form for simple screening surveys and a long form desirable for prospective, longitudinal observational research where aetiological factors in demarcated lesions are to be investigated in tandem with lesions distribution. Validation of the grading method is required, and its reliability and usefulness need to be tested in different age groups and different populations.

Oral rehabilitation of a patient with amelogenesis imperfecta using removable overlay denture: a clinical report.

AIM: The aim of this study was oral rehabilitation of 17-year old patient with amelogenesis imperfecta using removable overlay denture in order to satisfy her esthetic and functional expectations and enhance her self-image. BACKGROUND: Amelogenesis imperfecta (AI) is a group of genetic disorders that primarily affect the quality and quantity of amelogenesis in both primary and permanent dentitions. The main clinical characteristics are severe attrition, tooth sensitivity and unesthetic appearance. CASE REPORT: This clinical report illustrates the oral rehabilitation of a 17-year-old girl with hypoplastic-hypomature type of AI with cobalt-chromium (Co-Cr) overlay removable partial denture (ORPD) that is one of the most economical and biocompatible replacements for noble metal and nickel-chromium (Ni-Cr) alloy. CONCLUSION: The presented case report suggests that Co-Cr ORPD can be a good temporary or even permanent treatment option for AI patients with limited budget, low esthetic concerns or medical limitations. CLINICAL SIGNIFICANCE: There are major advantages in cast metal ORPDs; they are simpler, less traumatic and less expensive than fixed prosthetic options. This case report supports their use in patients with amelogenesis imperfecta.

Amelogenesis imperfecta: a clinician's challenge.

Defective enamel formation can be explained as defects occurring at the stages of enamel formation. Quantitative defects in matrix formation leads to hypoplastic form of amelogenesis imperfecta. Inadequate mineralization of matrix leads to hypocalcification and hypomaturation variants. The demarcation of matrix formation and mineralization is not so distinct. This paper describes a case of a 7-year-old boy with amelogenesis imperfecta - Type IA i.e., hypoplastic pitted autosomal dominant.

Amelogenesis imperfecta: an introduction.

Amelogenesis imperfecta (AI) is an inherited disorder that is associated with mutations in five genes (AMEL; ENAM; MMP20; KLK4 and FAM83H) with a wide range of clinical presentations (phenotypes). It affects the structure and appearance of enamel of all teeth, both in the primary and secondary dentition. In this review paper, we look at the epidemiology, classification, aetiology, clinical description and diagnosis of AI. In the following three papers of this series, we aim to describe the role of paediatric dentists, orthodontists and restorative dentists in the clinical management of patients with AI.

A multidisciplinary approach for the diagnosis of hypocalcified amelogenesis imperfecta in two Chilean families.

OBJECTIVE: The purpose of this study was to conduct a multidisciplinary analysis of a specific type of tooth enamel disturbance (amelogenesis imperfecta) affecting two Chilean families to obtain a precise diagnosis and to investigate possible underlying mutations. MATERIALS AND METHODS: Two non-related families affected with amelogenesis imperfecta were evaluated with clinical, radiographic and histopathological methods. Furthermore, pedigrees of both families were constructed and the presence of eight mutations in the enamelin gene (ENAM) and three mutations in the enamelysin gene (MMP-20) were investigated by PCR and direct sequencing. RESULTS: In the two affected patients, the dental malformation presented as soft and easily disintegrated enamel and exposed dark dentin. Neither of the affected individuals presented with a dental and skeletal open bite. Histologically, a high level of an organic matrix with prismatic organization was found. Genetic analysis indicated that the condition is autosomal recessive in one family and either autosomal recessive or due to a new mutation in the other family. Molecular mutational analysis revealed that none of the eight mutations previously described in the ENAM gene or the three mutations in the MMP-20 gene were present in the probands. CONCLUSION: A multidisciplinary analysis allowed for a diagnosis of hypocalcified amelogenesis imperfecta, Witkop type III, which was unrelated to previously described mutations in the ENAM or MMP-20 genes.

Prosthodontic management of patients with amelogenesis imperfecta.

INTRODUCTION: Amelogenesis Imperfecta (AI) is an heterogenous genetic disorder that disturbs the developing enamel structure. This rare ectodermal defect leads to a variety of clinical manifestations due to agenesis, hypoplasia, and/or hypomineralisation of the enamel. AIMS AND OBJECTIVES: To describe the prosthodontic management of dental anomalies commonly associated with AI. METHODS: By using the classification of Witkop and Rao (1971), the variation in clinical presentation of the different Types of AI are illustrated and discussed, in particular Type I AI and Type 4 AI. RESULTS AND CONCLUSIONS: Early diagnosis and prosthodontic management as part of a multidisciplinary, patient-centred approach are key factors to treatment success. Treatment options to address the oral complications are influenced by modifying factors including age, socioeconomic status, type and severity of the disorder, and intraoral status at the time of treatment planning. Ultimately, management includes pain and infection control, provision of aesthetics and restoration of function which may lead to patient satisfaction, psychological well-being and an improved quality of life.

Adhesive techniques and machineable high-performance polymer restorations for amelogenesis imperfecta in mixed dentition.

Amelogenesis imperfecta refers to a hereditary dysplasia of the enamel. As a result of various defects, qualitatively and/ or quantitatively abnormal enamel forms, while the dental structure remains normal. The following article describes the condition and presents the case of an 8-year-old boy who was dentally reconstructed both functionally and aesthetically using the adhesive technique and machinable high performance polymer restorations.

Amelogénesis imperfecta, caso clínico: tratamiento ortodóncico interceptivo / Amelogenesis imperfecta, clinical case: interceptive orthodontic treatment

La amelogénesis imperfecta (AI) es una anomalía de origen genómico que altera en diferente grado la estructura del esmalte, produciendo problemas de autoestima, deterioro de la salud bucal en general y la consecuente disminución de la calidad de vida. Es importante que el odontopediatra aborde al paciente desde etapas tempranas con un concepto multidisciplinario que contemple fases de tratamiento adecuadas para cada etapa de crecimiento.

Defining a new candidate gene for amelogenesis imperfecta: from molecular genetics to biochemistry.

Amelogenesis imperfecta is a group of genetic conditions that affect the structure and clinical appearance of tooth enamel. The types (hypoplastic, hypocalcified, and hypomature) are correlated with defects in different stages of the process of enamel synthesis. Autosomal dominant, recessive, and X-linked types have been previously described. These disorders are considered clinically and genetically heterogeneous in etiology, involving a variety of genes, such as AMELX, ENAM, DLX3, FAM83H, MMP-20, KLK4, and WDR72. The mutations identified within these causal genes explain less than half of all cases of amelogenesis imperfecta. Most of the candidate and causal genes currently identified encode proteins involved in enamel synthesis. We think it is necessary to refocus the search for candidate genes using biochemical processes. This review provides theoretical evidence that the human SLC4A4 gene (sodium bicarbonate cotransporter) may be a new candidate gene.

Case series: clinical findings and oral rehabilitation of patients with amelogenesis imperfecta.

BACKGROUND: Children with amelogenesis imperfecta (AI) experience many oral difficulties including sensitivity and aesthetics. The methods of treating AI children are limited and therefore a program of care was evaluated in order to assess the clinical efficacy of providing preventive and restorative treatments. CASE REPORTS: A non-randomised convenience sample of 12 patients with AI was evaluated. A comprehensive patient history was recorded, followed by a clinical and radiographic assessment of oral health. In 8/12 patients a hypoplastic form of AI was diagnosed, in 2/12 cases hypomaturation and in 2/12 cases hypocalcified form were noted. Chief complaints were mainly related to unsatisfactory aesthetics and dental sensitivity. In 8 patients there was active dental caries. Most of the patients had gingivitis and showed fair oral hygiene. The presence of non-enamel dental anomalies was recorded in 9 patients. TREATMENT: All patients received meticulous preventive care. Initial treatment depended on AI type and oral health of the patient. During the transition period, both conventional and resin modified glassionomer cements, as well as composite resin materials, were used to restore posterior teeth. Direct composite resin restorations were used to improve the appearance of anterior teeth. In 4 patients a long-lasting interdisciplinary approach including orthodontics, metal-ceramic crowns and fixed partial dentures, and direct composite restorations was required. FOLLOW-UP: Follow-up periods varied between 2-11 years. All children have been regularly recalled at 3 monthly intervals. Caries prevalence has remained low during the follow-up postoperative period and patients have reported satisfaction with the treatment they have received. CONCLUSION: AI is associated with multiple non-enamel anomalies and requires a complex treatment. Treatment planning is related to the age of the patient, the type and severity of the disorder, and the oral health of the patient. Early diagnosis, preventive care and timely treatment are of foremost importance to improve oral health in children with AI.

Amelogenésis imperfecta: criterios de clasificación y aspectos genéticos / Amelogenesis imperfecta: classification criteria and genetic aspects

La amelogénesis imperfecta es una alteración del esmalte que se puede presentar tanto en dentición decidua como permanente con diversas consecuencias negativas para los pacientes. La presente revisión describe los criterios diagnósticos, clasificación, etiología, casos esporádicos en los que se ha relacionado con otras alteraciones clínicas o enfermedades sistémicas, y su tratamiento; enfatizando la etiología y clasificación de esta alteración puesto que son las áreas en las que se han realizado muchos avances en los últimos años, especialmente relacionado con los aspectos genéticos.

Amelogenesis imperfecta is an enamel alteration that occurs in both deciduous and permanent dentition with diverse negative consequences for the patients. The present review describes the diagnostic criteria, classification, etiology, sporadic cases in which it is related to other clinical alterations or systemic diseases, and its treatment; emphasizing in the etiology and classification of this alteration since they are the areas in which many advances have been performed in the last years, specially related to the genetic aspects.

Hypocalcified type of amelogenesis imperfecta in a large family: clinical, radiographic, and histological findings, associated dento-facial anomalies, and resulting treatment load.

OBJECTIVE: The purpose of this study was to report on the clinical, radiographic, and histological dental findings and the resulting treatment load in a five-generation family with amelogenesis imperfecta (AI). MATERIAL AND METHODS: Thirteen affected and 15 unaffected individuals were examined clinically and radiographically. In addition, four exfoliated deciduous teeth were examined by scanning electron microscopy and microradiography. RESULTS: The mode of inheritance of AI was autosomal-dominant. At eruption, most of the tooth enamel was yellow, lacking translucency, and prone to gradual loss in subjects with AI. Post-eruptive breakdown of enamel was extensive in accordance with the histological observations of hypomineralized and porous enamel. Extensive enamel loss and discoloration were observed in older affected individuals. The treatment need had been extensive: 76.2% of the total number of teeth present in affected individuals had been treated with partial or full coverage compared to 1.7% of the teeth in unaffected relatives. Unaffected individuals had more endodontically treated teeth than AI-affected relatives. Adjunctive findings, e.g. tooth agenesis, tooth impaction, pulp stones, enlarged follicular space, and taurodontism, were rare in both groups. CONCLUSIONS: Affected family members had the hypocalcified type of AI, which is characterized by severe hypomineralization, extensive post-eruptive loss, and discoloration of the enamel. Adjunctive findings were rare. Individuals with the hypocalcified type of AI have an extensive restorative treatment load compared to unaffected relatives.

Clinical diagnosis and oral rehabilitation of a patient with amelogenesis imperfecta: a case report.

AIM: This clinical report describes the oral rehabilitation of a young female patient diagnosed with the hypocalcified, autosomal recessive type of Amelogenesis imperfecta (AI). A brief discussion on diagnosis of AI is also included. BACKGROUND: AI has been defined as a group of hereditary enamel defects not associated with evidence of systemic disease. It can be characterized by enamel hypoplasia and/or hypomaturation or hypocalcification of the existing teeth. Restoration for patients with this condition should be oriented toward the functional and esthetic rehabilitation and the protection of these teeth. REPORT: A 31-year-old female patient presented with concerns including extreme sensitivity; dissatisfaction with size, shape, and shade of teeth; and poor masticatory efficiency. She was very conscious about the appearance of her teeth and reported that her primary dentition was affected in the same manner. The specific objectives of this treatment were to eliminate tooth sensitivity, enhance esthetics, and restore masticatory function. Treatment included crown lengthening procedures and placement of anterior and posterior metal-ceramic crowns. A 12-month follow-up with clinical and radiographic examinations revealed no evidence of any untoward effects of the treatment on the restored teeth or their supporting structures. SUMMARY: Management of a patient with AI is a challenge for the clinician. The treatment options vary considerably depending on several factors such as the age of the patient, socio-economic status, periodontal condition, loss of tooth structure, severity of the disorder, and, most importantly, the patient's cooperation. The clinician has to consider the long-term prognosis of the treatment outcome. This clinical report describes the fabrication of metal ceramic and all metal crowns for the restoration of severely worn teeth in a patient with AI which requires meticulous maintenance of oral hygiene and patient co-operation.

Amelogenesis imperfecta.

Amelogenesis imperfecta (AI) represents a group of developmental conditions, genomic in origin, which affect the structure and clinical appearance of enamel of all or nearly all the teeth in a more or less equal manner, and which may be associated with morphologic or biochemical changes elsewhere in the body. The prevalence varies from 1:700 to 1:14,000, according to the populations studied. The enamel may be hypoplastic, hypomineralised or both and teeth affected may be discoloured, sensitive or prone to disintegration. AI exists in isolation or associated with other abnormalities in syndromes. It may show autosomal dominant, autosomal recessive, sex-linked and sporadic inheritance patterns. In families with an X-linked form it has been shown that the disorder may result from mutations in the amelogenin gene, AMELX. The enamelin gene, ENAM, is implicated in the pathogenesis of the dominant forms of AI. Autosomal recessive AI has been reported in families with known consanguinity. Diagnosis is based on the family history, pedigree plotting and meticulous clinical observation. Genetic diagnosis is presently only a research tool. The condition presents problems of socialisation, function and discomfort but may be managed by early vigorous intervention, both preventively and restoratively, with treatment continued throughout childhood and into adult life. In infancy, the primary dentition may be protected by the use of preformed metal crowns on posterior teeth. The longer-term care involves either crowns or, more frequently these days, adhesive, plastic restorations.

The new Enamel Defects Index: testing and expansion.

The Enamel Defects Index (EDI) was created based on three innovative principles: (i) a basic level of the three major categories of defects; (ii) more detailed subcategories of each major category; and (iii) each category scored independently as present [1] or absent [0], simplifying decision making. The aim of this investigation was to further test the index in a number of applications and to expand it to record defect subtype and treatment need. Testing was undertaken by operators with different levels of clinical experience. A computer-assisted learning (CAL) package was developed for operator training and calibration. The index was also used on clinical photographs and high-resolution digital images of exfoliated and extracted teeth. Scoring of photographs revealed substantial intra-operator agreement. Training using the CAL package resulted in significant improvement in index use. Intra-operator reproducibility was good to excellent, and interoperator reproducibility was good for buccal surfaces on digital images. Index expansion allowed information on defect subtype, location, and treatment need to be gathered readily. The EDI has high reproducibility and allows more rapid and accurate data collection from clinical and in vitro studies than the Fédération Dentaire Internationale Developmental Defects of Enamel index.

Phenotypic diversity and revision of the nomenclature for autosomal recessive amelogenesis imperfecta.

PURPOSE: The purpose of this study was to characterize the phenotype in 9 families with autosomal recessive amelogenesis imperfecta (ARAI), and to propose a classification system allowing inclusion and delineation of diverse ARAI phenotypes. STUDY DESIGN: Nine families with ARAI were evaluated clinically and radiographically. Exfoliated and extracted teeth were examined via light and scanning electron microscopy, with the enamel in one case evaluated by amino acid analysis. RESULTS: The 9 families demonstrated diverse ARAI phenotypes including localized hypoplastic, generalized thin hypoplastic, hypocalcified and hypomaturation AI types. CONCLUSIONS: Some ARAI phenotypes observed in this study and reported in the literature cannot be classified using currently accepted ARAI nomenclature. Therefore, we propose a revised nomenclature permitting both classification of all ARAI clinical forms and inclusion of anticipated molecular-based nomenclature, such as now exists for some X-linked and autosomal dominant AI subtypes.