The classification as well as the clinical manifestations of hereditary malformations of dentin are of great concern and have been deeply elucidated. The understanding of its genetic basis also increases progressively. Dentin sialophosphoprotein (DSPP) is the pathogenic gene of dentinogenesis imperfecta type Ⅱ, dentinogenesis imperfecta type Ⅲ and dentin dysplasia type Ⅱ. In this article, the classification of DSPP mutations as well as the resultant dysfunction of the mutant DSPP are summarized respectively and the corresponding clinical manifestations are analyzed. This work will provide a reference for the diagnosis and treatment of hereditary malformations of dentin.
Humans ; Dentinogenesis Imperfecta/pathology* ; Mutation ; Extracellular Matrix Proteins/genetics* ; Phosphoproteins/genetics* ; Sialoglycoproteins/genetics* ; Dentin/pathology*

OBJECTIVE: To explore the clinical and genetic characteristics of a Chinese pedigree affected with hereditary dentinogenesis imperfecta (DGI) type II. METHODS: Clinical data of the pedigree members were collected. Genomic DNA was extracted from peripheral blood samples and subjected to whole exome sequencing. RESULTS: Clinical characteristics of the affected family members have included amber teeth along with significant attrition, constricted roots and dentine hypertrophy leading to pulpal obliteration, which were suggestive of DGI type II. All of the affected members were found to have harbored a novel heterozygous c.2837delA (p.Asp946Valfs*368) variant of the DSPP gene which was predicted to be likely pathogenic. CONCLUSION The c.2837delA variant of the DSPP gene probably underlay the disease in this pedigree. Above finding has expanded the variant spectrum of DSPP gene and provided a basis for molecular diagnosis and genetic counseling for this pedigree.
Dentinogenesis Imperfecta/genetics* ; Extracellular Matrix Proteins/genetics* ; Humans ; Mutation ; Pedigree ; Phosphoproteins/genetics* ; Sialoglycoproteins/genetics*

OBJECTIVE: To analyze the clinical characteristics and the genetic cause of a Chinese patient with hereditary opalescent dentin, and to make an observation of the histologic and elemental features of the affected teeth. METHODS: We enrolled a patient affected with hereditary opalescent dentin. The medical history was collected and clinical examinations were performed for the phenotypic analyses. The blood sample was collected for DNA extraction and PCRs of the coding sequence of DSPP were done for sanger sequencing. The teeth samples were collected for histological evaluation and elemental analysis. RESULTS: The patient showed typical clinical manifestations of opalescent dentin and had enamel dysplasia and skeletal class III malocclusion. Several polymorphisms (c.727G>A, c.897A>G, c.2053_2054ins18bp, c.2548G>A, c.2645_2646ins9bp, c.2706T>C, c.2878A>G, c.3004A>G, c.3069_3086del18bp, c.3249A>C, c.3264T>C, c.3266_3400del135bp, c.3418A>G, c.3454G>A, c.3461_3462ins18bp, c.3606C>T) but no pathogenic mutations were identified in DSPP. The histological analyses of the patient's teeth showed characteristic abnormalities that were significantly different from normal teeth. The dentin tubules of the affected teeth were decreased in number and sparsed in arrangement, while in the control teeth, they were more regular. The enamel-dentin junction of the affected teeth was abnormal in its less scallopped outline compared with the control teeth under the scanning electronic microscopy. The Mg proportion of the patient's teeth (0.615 0%±0.261 6%) was lower than that of the control teeth (1.283 3%±0.322 1%), the P value was 0.040. The Ca proportion was the higher compared with the control teeth (34.865 0%±0.388 9% vs. 29.221 7%±2.248 4%), the P value was 0.015. The Ca/P ration of the patient's teeth was 1.981 2±0.019 3, which was higher than that of control teeth (1.775 9±0.111 6), the P value was 0.049. The differences of Mg, Ca proportion and Ca/P ration between the affected teeth and the control teeth were significant. The C and O proportion of the patient's teeth were lower and the P proportion was higher compared with the control teeth, however, the differences were not significant. CONCLUSION Our study of clinical manifestation analysis, genetic variants sequencing and histological observation has enlarged the phenotypic spectrum of hereditary opalescent dentin, and the genetic and histological results would contribute to further studies.
Dental Enamel ; Dentin ; Dentinogenesis Imperfecta/genetics* ; Genetic Testing ; Humans ; Polymorphism, Genetic ; Tooth

Dentinogenesis imperfecta is a dominant autosomal hereditary disorder of dentin formation that affects the deciduous and permanent teeth. Its etiology is characterized by inadequate cell differentiation during odontogenesis. The clinical characteristics of dentinogenesis imperfecta are discolored teeth with a translucency that varies from gray to brown or amber. Radiographically, the teeth exhibit pulp obliteration, thin and short roots, bell-shaped crowns, and periapical bone rarefaction. The aim of this report was to present a case of dentinogenesis imperfecta type II that was followed up over a 17-year period. This report also presents scanning electron microscopy images of the enamel and dentin, showing that both were altered in the affected teeth. The disease characteristics and the treatments that were administered are reported in this study to guide dentists with respect to the need for early diagnosis and adequate follow-up to avoid major sequelae.
Amber ; Cell Differentiation ; Crowns ; Dental Enamel ; Dentin ; Dentinogenesis Imperfecta* ; Dentinogenesis* ; Dentists ; Early Diagnosis ; Follow-Up Studies* ; Humans ; Microscopy, Electron, Scanning ; Odontogenesis ; Tooth

OBJECTIVETo identify the causative mutation in a Chinese family affected with dentinogenesis imperfecta shields type II (DGI-II).

METHODSWith informed consent obtained from all participants, peripheral blood or chorionic villi samples were collected from the family members. Genomic DNA was extracted using a standard SDS-proteinase K-phenol/chloroform method. The whole coding region and exon/intron boundaries of the DSPP gene were amplified with polymerase chain reaction (PCR) and subjected to Sanger sequencing. To confirm the pathogenicity of the identified mutation, an Alu I recognition sequence was introduced into the mutant allele using mismatch primers by semi-nested PCR. Restriction fragment length polymorphism (RFLP) analysis was then carried out for all family members and 60 unrelated healthy controls. Meanwhile, mini-DSPP constructs were conducted to confirm the effect of the mutation in vitro.

RESULTSA splicing site mutation, c.52-1G>A, which was located upstream of exon 3, was found in all three patients and the fetus of the proband. Restriction analysis confirmed that all unaffected individuals and the 60 healthy controls did not carry the same mutation. The expression of minigene showed that the exon 3 of the DSPP gene was skipped during the transcription.

CONCLUSIONA novel pathogenic splicing-mutation c.52-1G>A has been detected in a Chinese family affected with DGI-II, which enabled prenatal diagnosis for the fetus of the proband.

Adult ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Child, Preschool ; Dentinogenesis Imperfecta ; genetics ; Exons ; Extracellular Matrix Proteins ; genetics ; Female ; Humans ; Male ; Molecular Sequence Data ; Pedigree ; Phosphoproteins ; genetics ; Point Mutation ; RNA Splicing ; Sialoglycoproteins ; genetics

Dentinogenesis Imperfecta, with a high incidence rate of 1 : 6 - 8000, is inherited by autosomal dominant genetic transmission. This dental disorder causes discoloration of the teeth and the enamel and dentin show hypoplastic or hypocalcified defects which lead to frequent fractures and rapid attrition. Therefore, timely treatment is necessary for the preservation of the remaining teeth. In this particular case, a 19-year-old patient suffering from Type 1 dentinogenesis imperfecta showed signs of brownish hued teeth with multiple fractures, a loss of vertical dimension, excessive interdental space in the maxillary anterior teeth, and a lack of 5 posterior teeth. To improve the esthetic appearance of the anterior teeth, the vertical dimension was increased. Resin caps were used to alleviate the difficulty of taking an impression of multiple teeth at once. Monolithic zirconia materials used in this case showed high fracture strength and the ability to mask the discoloration of the teeth and therefore, functionally and esthetically favorable results were achieved.
Dental Enamel ; Dentin ; Dentinogenesis Imperfecta* ; Humans ; Incidence ; Masks ; Rehabilitation* ; Tooth ; Vertical Dimension ; Young Adult

PURPOSE: This study was performed to evaluate the prevalence of all types and subtypes of dental anomalies among 7- to 35-year-old patients by using panoramic radiographs. MATERIALS AND METHODS: This cross-sectional study was conducted on 1649 people in Hamadan City, in 2012-2013. The prevalence of four types and 12 subtypes of dental anomalies was evaluated by two observers separately by using panoramic radiography. Dental anomalies were divided into four types: (a) shape (including fusion, taurodontism, and dens invagination); (b) number (including hypodontia, oligodontia, and hyperdontia); (c) structure (including amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia); and (d) position (including displacement, impaction, and dilacerations). RESULTS: The reliability between the two observers was 79.56% according to the Kappa statistics. The prevalence of dental anomalies diagnosed by panoramic radiographs was 29%. Anomalies of position and number were the most common types of abnormalities, and anomalies of shape and structure were the least in both genders. Anomalies of impaction (44.76%), dilacerations (21.11%), hypodontia (15.88%), taurodontism (9.29%), and hyperdontia (6.76%) were the most common subtypes of dental anomalies. The anomalies of shape and number were more common in the age groups of 7-12 years and 13-15 years, respectively, while the anomalies of structure and position were more common among the other age groups. CONCLUSION: Anomalies of tooth position were the most common type of dental anomalies, and structure anomalies were the least in this Iranian population. The frequency and type of dental anomalies vary within and between populations, confirming the role of racial factors in the prevalence of dental anomalies.
Adult* ; Amelogenesis Imperfecta ; Anodontia ; Cross-Sectional Studies ; Dentin ; Dentinogenesis Imperfecta ; Dentition ; Humans ; Iran* ; Prevalence* ; Radiography, Panoramic ; Tooth

OBJECTIVETo study the genetic etiology of an autosomal dominant dentinogenesis imperfecta in a Chinese family.

METHODSThe molecular change of the disease in the family was analyzed through the clinical examination, linkage analysis, mutational screening of the DSPP gene and restriction fragment length polymorphism analysis.

RESULTSThe disease related gene was completely linked with microsatellite marker D4S1534. We found a novel mutation in the first exon of the DSPP gene (c.49C>T, p.Pro17Ser). All patients in the family had the mutation, while this mutation was not observed in the normal individuals of this family and 100 unrelated controls.

CONCLUSIONThe p.Pro17Ser identified in the family was a new pathogenic mutation. Our finding provided further understanding of the molecular mechanism of dentinogenesis imperfecta.

Amino Acid Sequence ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Dentinogenesis Imperfecta ; genetics ; Exons ; Extracellular Matrix Proteins ; genetics ; Female ; Humans ; Male ; Microsatellite Repeats ; Molecular Sequence Data ; Mutation ; Pedigree ; Phosphoproteins ; Sialoglycoproteins ; Young Adult

Hereditary opalescent dentin is a rare autosomal dominant inherited disease of dentin development. A case of hereditary opalescent dentin was reported, and the pathogenesis, family tree and restoration methods were reviewed.
Dentinogenesis Imperfecta ; Humans ; Pedigree

Hereditary dentinogenesis imperfecta is a rare autosomal dominant hereditary disease. This article reported a case of hereditary opalescent dentin and discussed the clinical features and treatment.
Dentinogenesis Imperfecta ; Humans