The dental perspective on osteogenesis imperfecta in a Danish adult population.

BACKGROUND: To report on dental characteristics and treatment load in Danish adult patients with osteogenesis imperfecta (OI). METHODS: Oral examination of 73 patients with OI was performed and OI type I, III, and IV were represented by 75.3%, 8.2%, and 16.4%, respectively. Patients were diagnosed as having dentinogenesis imperfecta (DI) if they had clinical and radiological signs of DI. In the data analysis, mild OI (type I) was compared to moderate-severe OI (type III and IV). RESULTS: Discoloration of teeth was prevalent in patients with moderate-severe compared to mild OI (83.3% vs. 5.5%, p < 0.001). Cervical constriction and pulpal obliteration were frequent findings in patients with moderate-severe OI (61.1% and 88.9%, respectively), whereas pulp stones and taurodontism were diagnosed in patients with mild OI only (29.1% and 9.1%, respectively). DI was found in 24.7% of OI patients and considerably more frequent in patients with moderate-severe (94.4%) compared to mild OI (1.8%) (p < 0.001). The number of teeth with artificial crowns was significantly higher in patients with moderate-severe OI than in patients with mild OI (median 1.5, range 0-23 vs. median 0, range 0-14) (p < 0.001). The number of teeth with fillings in patients with mild OI was significantly higher than in patients with moderate-severe OI (mean 9.7, SD 5.1, median 9.0, range 1-21 vs. mean 5.0, SD 4.4, median 4.0, range 0-16) (p < 0.001). CONCLUSIONS: One fourth of patients with OI had DI, and the vast majority of them had moderate-severe OI. Whereas discoloration of teeth, cervical constriction and pulp obliteration were frequent findings in patients with moderate-severe OI, pulp stones and taurodontism were found in patients with mild OI only. In patients with moderate-severe OI, the dental treatment load was dominated by prosthetic treatment, whereas restorative treatment with fillings was more prevalent in patients with mild OI.

Dentinogenesis Imperfecta: A Case Report of Five Patients in the Same Family Group / Dentinogenesis Imperfecta: Un Reporte de Caso de Cinco Pacientes en el Mismo Grupo Familiar

Dentinogenesis imperfecta (DI) is a type of dentin dysplasia that affects the dentin structure of one or both dentitions, which may be classified in three types. The aim of this report was to show the clinical and radiographic features of the four cases of DI in the same family group. Five brothers were checked clinically and radiographically. Two individuals were diagnosed, by their phenotypic features and medical history, with DI type I; two of them with DI type II and one case without signs of DI. It is important to know the features of dentinogenesis imperfecta to perform a comprehensive dental care, including the right diagnosis and an effective treatment plan.

La dentinogénesis imperfecta (DI) es un tipo de displasia de la dentina que afecta su estructura en una o ambas denticiones. La DI puede clasificarse en tres tipos. El objetivo de este informe fue demostrar las características clínicas y radiológicas de los cuatro casos de DI en un mismo grupo familiar. Cinco hermanos fueron controlados clínica y radiográficamente. Dos individuos fueron diagnosticados, por sus características fenotípicas y antecedentes clínicos, con el tipo de DI I; dos de ellos con DI de tipo II y un caso sin signos de DI. Es importante conocer las características de la dentinogénesis imperfecta para poder realizar una atención odontológica integral, lo que permitirá desarrollar un diagnóstico correcto y un plan de tratamiento efectivo.

Isolated dentinogenesis imperfecta and dentin dysplasia: revision of the classification.

Dentinogenesis imperfecta is an autosomal dominant disease characterized by severe hypomineralization of dentin and altered dentin structure. Dentin extra cellular matrix is composed of 90% of collagen type I and 10% of non-collagenous proteins among which dentin sialoprotein (DSP), dentin glycoprotein (DGP) and dentin phosphoprotein (DPP) are crucial in dentinogenesis. These proteins are encoded by a single gene: dentin sialophosphoprotein (DSPP) and undergo several post-translational modifications such as glycosylation and phosphorylation to contribute and to control mineralization. Human mutations of this DSPP gene are responsible for three isolated dentinal diseases classified by Shield in 1973: type II and III dentinogenesis imperfecta and type II dentin dysplasia. Shield classification was based on clinical phenotypes observed in patient. Genetics results show now that these three diseases are a severity variation of the same pathology. So this review aims to revise and to propose a new classification of the isolated forms of DI to simplify diagnosis for practitioners.

Management of dentinogenesis imperfecta: a review of two case reports.

Dentinogenesis imperfecta (DI) is an inherited disorder that affects dentin and often manifests as tooth discoloration; in addition, the dentition is also extremely susceptible to wear. Treatment of DI focuses primarily on protecting affected dentin, reducing sensitivity, and improving esthetics. Routine restorative materials, such as amalgams and composites, may be used. In more severe cases, the treatment of choice is full coverage crowns, while bonding of veneers may be used to improve the esthetics of the anterior teeth. This study presents two cases of Type II DI in the same family and the management of each case. Restorative management included amalgams, composite veneers, crowns, bridges, and overdentures.

Hereditary dentine diseases resulting from mutations in DSPP gene.

OBJECTIVES: This review groups the newest results of molecular analyses of DSPP gene for patients diagnosed either with dentinogenesis imperfecta type II/III or dentine dysplasia and tries to link the phenotypes with specific mutations in the DSPP gene. DATA: The review includes biochemical data introducing a specificity of DSPP protein which justifies it as a critical factor for dentine mineralization and maturation. The majority of the review analyzes mutations in the DSPP gene which result in phenotypes of dentinogenesis imperfecta types II or/and III or dentine dysplasia. SOURCES: An electronic search was conducted in the databases of Pub Med and supplemented by manual study of relevant references. STUDY SELECTION: 52 out of 108 references were finally selected for the review based on the novelty and/or originality of data. CONCLUSION: Hereditary dentine disorders dentinogenesis imperfecta type II/III and dentine dysplasia are currently proposed to be one disease with distinct clinical manifestations reflecting various mutations in the same DSPP gene. For years both disorders were linked exclusively to mutations in the DSP code but a growing number of papers describe mutations which manifest a similar phenotype but are localized in the strongly repetitive sequence of the 3' terminus of the DSPP which codes DPP protein. Our search suggests that the localization of mutation in the sequence of the DSPP gene might result in a different phenotype due to the diverse cellular fate of the mutated protein. Thus comprehensive research on the cellular fate and processing of both normal and mutated DSPP is still required.

A novel splicing mutation alters DSPP transcription and leads to dentinogenesis imperfecta type II.

Dentinogenesis imperfecta (DGI) type II is an autosomal dominant disease characterized by a serious disorders in teeth. Mutations of dentin sialophosphoprotein (DSPP) gene were revealed to be the causation of DGI type II (DGI-II). In this study, we identified a novel mutation (NG_011595.1:g.8662T>C, c.135+2T>C) lying in the splice donor site of intron 3 of DSPP gene in a Chinese Han DGI-II pedigree. It was found in all affected subjects but not in unaffected ones or other unrelated healthy controls. The function of the mutant DSPP gene, which was predicted online and subsequently confirmed by in vitro splicing analysis, was the loss of splicing of intron 3, leading to the extended length of DSPP mRNA. For the first time, the functional non-splicing of intron was revealed in a novel DSPP mutation and was considered as the causation of DGI-II. It was also indicated that splicing was of key importance to the function of DSPP and this splice donor site might be a sensitive mutation hot spot. Our findings combined with other reports would facilitate the genetic diagnosis of DGI-II, shed light on its gene therapy and help to finally conquer human diseases.

Dentinogénesis imperfecta tipo I / Dentinogenesis imperfecta, type I

La dentinogénesis imperfecta (DI) es una anomalía dentaria determinada genéticamente y caracterizada clínicamente por una apariencia ámbar opalescente de la dentina. Se presenta la resolución clínica, con seguimiento y control a 3 años, de un paciente con diagnóstico de DI. La identificación temprana de esta entidad y el tratamiento oportuno y multidisciplinario, contribuyen a mejorar el pronóstico de la misma.

Successful bleaching of teeth with dentinogenesis imperfecta discoloration: a case report.

UNLABELLED: Dentinogenesis imperfecta (DI) is a hereditary condition that can cause discoloration of teeth in addition to other dental abnormalities. Patients often present to the dentist with a main goal of improving their esthetics. A myriad of treatment options have been described for this condition. This clinical report describes the management of a young adult with DI who desired improvement in dental esthetics after orthodontic treatment. As a result of his condition, the patient's dentition exhibited the classic generalized dark amber opalescence. A 14% hydrogen peroxide gel was used for bleaching of the maxillary and mandibular teeth, performed by the patient at home. The patient was followed at different intervals, and the improvement in teeth shade was significant and remained stable at 3.5 years. No adverse effects were observed. This article is the first case report in the literature describing the long-term follow-up of teeth bleaching in a patient with DI. CLINICAL SIGNIFICANCE: Teeth bleaching may be considered as the first choice of treatment in dentinogenesis imperfecta patients. If successful, it offers a simple, conservative, and economical solution to satisfy the esthetic requirements of these patients.

Novel dentin phosphoprotein frameshift mutations in dentinogenesis imperfecta type II.

The dentin sialophosphoprotein (DSPP) gene encodes the most abundant non-collagenous protein in tooth dentin and DSPP protein is cleaved into several segments including the highly phosphorylated dentin phosphoprotein (DPP). Mutations in the DSPP gene have been solely related to non-syndromic form of hereditary dentin defects. We recruited three Korean families with dentinogenesis imperfecta (DGI) type II and sequenced the exons and exon-intron boundaries of the DSPP gene based on the candidate gene approach. Direct sequencing of PCR products and allele-specific cloning of the highly repetitive exon 5 revealed novel single base pair (bp) deletional mutations (c.2688delT and c.3560delG) introducing hydrophobic amino acids in the hydrophilic repeat domain of the DPP coding region. All affected members of the three families showed exceptionally rapid pulp chambers obliteration, even before tooth eruption. Individuals with the c.3560delG mutation showed only mild, yellowish tooth discoloration, in contrast to the affected individuals from two families with c.2688delT mutation. We believe that these results will help us to understand the molecular pathogenesis of DGI type II as well as the normal process of dentin biomineralization.

Case report: Clinical, histological and ultrastructural characterization of type II dentinogenesis imperfecta.

BACKGROUND: Type II dentinogenesis imperfecta (DGIII) is an autosomal dominant dental development anomaly that affects both the primary and permanent dentition. CASE REPORT: This case report describes the clinical, radiographic and morphological characteristics of the teeth of a seven-year-old child with DGI-II determined by optical microscopy and scanning electron microscopy. TREATMENT: This consisted of extraction of the primary teeth with periapical lesions due to the advanced state of tooth resorption. Aesthetic restorations were performed on the mandibular anterior teeth and occlusal fissure sealants were applied to erupting teeth. A removable partial upper denture was made in order to return anterior aesthetic function and to aid mastication and speech. FOLLOW UP: The child was examined at 3 month intervals. Over the following 3 years the prosthesis was replaced due to facial growth and fluoride was applied at each follow-up visit to all teeth. The patient remains in follow up and management. CONCLUSION: Individuals with DGI-II must not neglect their dental health. Early diagnosis, professional advice and treatment with periodic follow-up can help improve the quality of life of such patients.

Dentinogenesis imperfecta--clinical presentation and management.

UNLABELLED: Dentinogenesis imperfecta (DI) is a hereditary condition which affects the development of dentine in both the primary and permanent dentitions. Three types of DI have been described in the literature. The presentation of DI is variable, depending on the type and severity of the disease. Early intervention in the treatment of a patient with DI is extremely important both for psycho-social and for functional reasons. This paper attempts to describe the clinical presentation and management of DI, and explores its association with certain medical conditions. CLINICAL RELEVANCE: Recognition of DI is important, so that correct treatment principles may be instituted.

Dentinogenesis imperfecta in children with osteogenesis imperfecta: a clinical and ultrastructural study.

AIM: The aim of this study was to assess the correlation between osteogenesis imperfecta (OI) and dentinogenesis imperfecta (DI) from both a clinical and histological point of view, particularly clarifying the structural and ultrastructural dentine changes. DESIGN: Sixteen children (6-12 years aged) with diagnosis of OI were examined for dental alterations referable to DI. For each patient, the OI type (I, III, or IV) was recorded. Extracted or normally exfoliated primary teeth were subjected to a histological examination (to both optical microscopy and confocal laser-scanning microscopy). RESULTS: A total of ten patients had abnormal discolourations referable to DI: four patients were affected by OI type I, three patients by OI type III, and three patients by OI type IV. The discolourations, yellow/brown or opalescent grey, could not be related to the different types of OI. Histological exam of primary teeth showed severe pathological change in the dentin, structured into four different layers. A collagen defect due to odontoblast dysfunction was theorized to be on the base of the histological changes. CONCLUSIONS: There is no correlation between the type of OI and the type of discolouration. The underlying dentinal defect seems to be related to an odontoblast dysfunction.

De novo mutation in the DSPP gene associated with dentinogenesis imperfecta type II in a Japanese family.

Dentinogenesis imperfecta (DGI) type II is one of the most common dominantly inherited dentin defects, in which both the primary and permanent teeth are affected. Here, we report a Japanese family with autosomal-dominant DGI type II, including both molecular genetic defects and pathogenesis with histological analysis. Mutation analysis revealed a mutation (c.53T>A, p.V18D, g.1192T>A) involving the second nucleotide of the first codon within exon 3 of the dentin sialophosphoprotein (DSPP) gene. This mutation has previously been reported in a Korean family. Thus far, 24 allelic DSPP mutations have been reported, and this is the seventh mutation involving the DSPP V18 residue. Among those, only one other was shown to be caused by a de novo mutation, and that mutation also affected the V18 amino acid residue. The DSPP V18 residue is highly conserved among other mammalian species. These findings thus suggest that the V18 amino acid might be a sensitive mutational hot spot, playing a critical role in the pathogenesis of DGI.

Hereditary dentine disorders: dentinogenesis imperfecta and dentine dysplasia.

The hereditary dentine disorders, dentinogenesis imperfecta (DGI) and dentine dysplasia (DD), comprise a group of autosomal dominant genetic conditions characterised by abnormal dentine structure affecting either the primary or both the primary and secondary dentitions. DGI is reported to have an incidence of 1 in 6,000 to 1 in 8,000, whereas that of DD type 1 is 1 in 100,000. Clinically, the teeth are discoloured and show structural defects such as bulbous crowns and small pulp chambers radiographically. The underlying defect of mineralisation often results in shearing of the overlying enamel leaving exposed weakened dentine which is prone to wear. Currently, three sub-types of DGI and two sub-types of DD are recognised but this categorisation may change when other causative mutations are found. DGI type I is inherited with osteogenesis imperfecta and recent genetic studies have shown that mutations in the genes encoding collagen type 1, COL1A1 and COL1A2, underlie this condition. All other forms of DGI and DD, except DD-1, appear to result from mutations in the gene encoding dentine sialophosphoprotein (DSPP), suggesting that these conditions are allelic. Diagnosis is based on family history, pedigree construction and detailed clinical examination, while genetic diagnosis may become useful in the future once sufficient disease-causing mutations have been discovered. Differential diagnoses include hypocalcified forms of amelogenesis imperfecta, congenital erythropoietic porphyria, conditions leading to early tooth loss (Kostmann's disease, cyclic neutropenia, Chediak-Hegashi syndrome, histiocytosis X, Papillon-Lefevre syndrome), permanent teeth discolouration due to tetracyclines, Vitamin D-dependent and vitamin D-resistant rickets. Treatment involves removal of sources of infection or pain, improvement of aesthetics and protection of the posterior teeth from wear. Beginning in infancy, treatment usually continues into adulthood with a number of options including the use of crowns, over-dentures and dental implants depending on the age of the patient and the condition of the dentition. Where diagnosis occurs early in life and treatment follows the outlined recommendations, good aesthetics and function can be obtained.

Dentinogenesis imperfecta: a case report.

Dentinogenesis imperfecta is an autosomal dominant disorder of tooth development characterized by the presence of opalescent dentin, resulting in a dusky blue to brownish discoloration of the teeth. This condition is genetically and clinically heterogeneous; it may affect only the teeth or it may be associated with the osteogenesis imperfecta. Dentinogenesis imperfecta has been subdivided into three types: type I is associated with osteogenesis imperfecta; in type II there is no associated osteogenesis imperfecta; and when the condition is associated with the Brandywine triracial isolate and large pulp chambers it is classified as type III. This report describes a 16-year-old female patient who showed the characteristic dental features of dentinogenesis imperfecta type II. The etiology and prevalence of the disorder, and a comprehensive treatment plan, will be briefly reviewed.

Dentinogenesis imperfecta type II: an affected family saga.

Dentinogenesis imperfecta (DI) type II or hereditary opalescent dentin is inherited in simple autosomal dominant mode with high penetrance and low mutation rate. It generally affects both the deciduous and permanent dentitions. DI type II corresponds to a localized form of mesodermal dysplasia, observed in histodifferentiation. Early diagnosis and treatment are therefore, fundamental, aiming at obtaining a favourable prognosis since late intervention makes treatment more complex. We present two cases of DI type II with the disease affecting three generations of a family in India, and briefly highlight the molecular basis of this disease.

Disorders of human dentin.

Dentin, the most abundant tissue in teeth, is produced by odontoblasts, which differentiate from mesenchymal cells of the dental papilla. Dentinogenesis is a highly controlled process that results in the conversion of unmineralized predentin to mineralized dentin. By weight, 70% of the dentin matrix is mineralized, while the organic phase accounts for 20% and water constitutes the remaining 10%. Type I collagen is the primary component (>85%) of the organic portion of dentin. The non-collagenous part of the organic matrix is composed of various proteins, with dentin phosphoprotein predominating, accounting for about 50% of the non-collagenous part. Dentin defects are broadly classified into two major types: dentinogenesis imperfectas (DIs, types I-III) and dentin dysplasias (DDs, types I and II). To date, mutations in DSPP have been found to underlie the dentin disorders DI types II and III and DD type II. With the elucidation of the underlying genetic mechanisms has come the realization that the clinical characteristics associated with DSPP mutations appear to represent a continuum of phenotypes. Thus, these disorders should likely be called DSPP-associated dentin defects, with DD type II representing the mild end of the phenotypic spectrum and DI type III representing the severe end.

Hereditary dentin defects.

By the Shields classification, articulated over 30 years ago, inherited dentin defects are divided into 5 types: 3 types of dentinogenesis imperfecta (DGI), and 2 types of dentin dysplasia (DD). DGI type I is osteogenesis imperfecta (OI) with DGI. OI with DGI is caused, in most cases, by mutations in the 2 genes encoding type I collagen. Many genes are required to generate the enzymes that catalyze collagen's diverse post-translational modifications and its assembly into fibers, fibrils, bundles, and networks. Rare inherited diseases of bone are caused by defects in these genes, and some are occasionally found to include DGI as a feature. Appreciation of the complicated genetic etiology of DGI associated with bony defects splintered the DGI type I description into a multitude of more precisely defined entities, all with their own designations. In contrast, DD-II, DGI-II, and DGI-III, each with its own pattern of inherited defects limited to the dentition, have been found to be caused by various defects in DSPP (dentin sialophosphoprotein), a gene encoding the major non-collagenous proteins of dentin. Only DD-I, an exceedingly rare condition featuring short, blunt roots with obliterated pulp chambers, remains untouched by the revolution in genetics, and its etiology is still a mystery. A major surprise in the characterization of genes underlying inherited dentin defects is the apparent lack of roles played by the genes encoding the less-abundant non-collagenous proteins in dentin, such as dentin matrix protein 1 (DMP1), integrin-binding sialoprotein (IBSP), matrix extracellular phosphoglycoprotein (MEPE), and secreted phosphoprotein-1, or osteopontin (SPP1, OPN). This review discusses the development of the dentin extracellular matrix in the context of its evolution, and discusses the phenotypes and clinical classifications of isolated hereditary defects of tooth dentin in the context of recent genetic data respecting their genetic etiologies.

Phenotypic variation in dentinogenesis imperfecta/dentin dysplasia linked to 4q21.

Dentinogenesis imperfecta (DGI) and dentin dysplasia (DD) are allelic disorders that primarily affect the formation of tooth dentin. Both conditions are autosomal-dominant and can be caused by mutations in the dentin sialophosphoprotein gene (DSPP, 4q21.3). We recruited 23 members of a four-generation kindred, including ten persons with dentin defects, and tested the hypothesis that these defects are linked to DSPP. The primary dentition showed amber discoloration, pulp obliteration, and severe attrition. The secondary dentition showed either pulp obliteration with bulbous crowns and gray discoloration or thistle-tube pulp configurations, normal crowns, and mild gray discoloration. Haplotype analyses showed no recombination between three 4q21-q24 markers and the disease locus. Mutational analyses identified no coding or intron junction sequence variations associated with affection status in DMP1, MEPE, or the DSP portion of DSPP. The defects in the permanent dentition were typically mild and consistent with a diagnosis of DD-II, but some dental features associated with DGI-II were also present. We conclude that DD-II and DGI-II are milder and more severe forms, respectively, of the same disease.