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Background Molar-incisor malformation (MIM) is a recently described dental abnormality. While MIM mimics dentin dysplasia, it presents in a localized pattern. Furthermore, it is speculated that MIM is caused by significant early-life medical history. Aim The purpose of this study is to present a series of MIM cases and compare the findings with the literature. Design An extensive search of all published cases of MIM in the English-language literature was conducted. Additionally, an institutional review board-approved retrospective search was performed within the University of Florida oral pathology biopsy service archives. Radiographic consultation cases were also included. Cases lacking radiographs were excluded. Results Seventy-nine cases were identified in the literature, and eight cases were identified in our retrospective search. All but one case involved the permanent first molars. The average age at diagnosis was 9 years. Many patients reported significant early-life medical histories. Conclusions MIM usually affects the permanent first molars and may be linked to early-life medical conditions or interventions. Oral healthcare providers, especially paediatric dentists, should be aware of MIM to avoid misdiagnosing it as dentin dysplasia. Long-term follow-up studies with thorough medical history documentation are essential to understand the pathogenesis and aetiology and to create treatment guidelines.

Poly(ADP-ribose) polymerase (Parp)-1 catalyzes polyADP-ribosylation using NAD+ and is involved in the DNA damage response, genome stability, and transcription. In this study, we demonstrated that aged Parp-1&minus, /&minus, mouse incisors showed more frequent dental dysplasia in both ICR/129Sv mixed background and C57BL/6 strain compared to aged Parp-1+/+ incisors, suggesting that Parp-1 deficiency could be involved in development of dental dysplasia at an advanced age. Computed tomography images confirmed that dental dysplasia was observed at significantly higher incidences in Parp-1&minus, mice. The relative calcification levels of Parp-1&minus, incisors were higher in both enamel and dentin (p &lt, 0.05). Immunohistochemical analysis revealed (1) Parp-1 positivity in ameloblasts and odontoblasts in Parp-1+/+ incisor, (2) weaker dentin sialoprotein positivity in dentin of Parp-1&minus, incisor, and (3) bone sialoprotein positivity in dentin of Parp-1&minus, incisor, suggesting ectopic osteogenic formation in dentin of Parp-1&minus, incisor. These results indicate that Parp-1 deficiency promotes odontogenic failure in incisors at an advanced age. Parp-1 deficiency did not affect dentinogenesis during the development of mice, suggesting that Parp-1 is not essential in dentinogenesis during development but is possibly involved in the regulation of continuous dentinogenesis in the incisors at an advanced age.

A amelogênese imperfeita compreende um grupo de condições com alterações do desenvolvimento na estrutura do esmalte dentário que afetam a dentição decídua e permanente e as principais implicações clínicas são: estética prejudicada, hipersensibilidade dentinária, dificuldade na higiene bucal, cáries recorrentes, inflamação gengival e perda da dimensão vertical. O tratamento varia de acordo com o tipo e a gravidade do caso, a fase do desenvolvimento dentário, o nível socioeconômico e as expectativas e anseios do paciente, podendo ser levados anos até o estabelecimento do tratamento definitivo. O presente trabalho tem como objetivo relatar e descrever as etapas clínicas de um caso de amelogênese imperfeita com restabelecimento da estética e função através de laminados cerâmicos ultrafinos, confeccionados em IPS e.max (IvoclarVivadent), com acompanhamento de um ano após a cimentação das restaurações. Conclui-se que os laminados cerâmicos podem ser uma alternativa interessante para o tratamento definitivo de casos mais brandos de amelogênese imperfeita, com otimização dos resultados estéticos e recuperação da autoestima do paciente.Descritores: Amelogênese Imperfeita; Facetas Dentárias; Estética Dentária.ReferênciasAldred MJ, Savarirayan R, Crawford PJ. Amelogenesis imperfecta: a classification and catalogue for the 21st century. Oral Dis. 2003;9(1):19-23.Bäckman B, Holm AK. Amelogenesis imperfecta: prevalence and incidence in a northern Swedish county. Community Dent Oral Epidemiol. 1986; 14(1):43-7.Chaudhary M, Dixit S, Singh A, Kunte S. Amelogenesis imperfecta: Report of a case and review of literature. J Oral Maxillofac Pathol. 2009;13(2):70-7.Witkop CJ Jr. Amelogenesis imperfecta, dentinogenesis imperfecta and dentin dysplasia revisited: problems in classification. J Oral Pathol. 1988;17(9-10):547-53.Ooya K, Nalbandian J, Noikura T. Autosomal recessive rough hypoplastic amelogenesis imperfecta. A case report with clinical, light microscopic, radiographic, and electron microscopic observations. Oral Surg Oral Med Oral Pathol. 1988;65(4):449-58.Witkop CJ Jr, Kuhlmann W, Sauk J. Autosomal recessive pigmented hypomaturation amelogenesis imperfecta. Report of a kindred. Oral Surg Oral Med Oral Pathol. 1973;36(3):367-82.Crawford PJ, Aldred M, Bloch-Zupan A. Amelogenesis imperfecta. Orphanet J Rare Dis. 2007;2:17.Seow WK. Clinical diagnosis and management strategies of amelogenesis imperfectavariants. Pediatr Dent. 1993;15(6):384-93.Yip HK, Smales RJ. Oral rehabilitation of young adults with amelogenesis imperfecta. Int J Prosthodont. 2003 Jul-Aug;16(4):345-9.McDonald S, Arkutu N, Malik K, Gadhia K, McKaig S. Managing the paediatric patient with amelogenesis imperfecta. Br Dent J. 2012;212(9):425-28.Ozturk N, Sari Z, Ozturk B. An interdisciplinary approach for restoring function and esthetics in a patient with amelogenesis imperfecta and malocclusion: a clinical report. J Prosthet Dent. 2004;92(2):112-5.Harley KE, Ibbetson RJ. Dental anomalies--are adhesive castings the solution? Br Dent J. 1993;174(1):15-22.Walter B. Prosthetic rehabilitation of a case of total amelogenesis imperfecta. Actual Odontostomatol. 1991;45(174):213-26. French.Chen C-F, Hu JCC, Estrella MRP, Peters MC, Bresciani E. Assessment of restorative treatment of patients with amelogenesis imperfecta. Pediatr Dent. 2013;35(4):337-42.Ramos AL, Pascotto RC, Iwaki Filho L, Hayacibara RM, Boselli G. Interdisciplinary treatment for a patient with open-bite malocclusion and amelogenesis imperfecta. Am J Orthod Dentofacial Orthop. 2011;139(4 Suppl):S145-53.Pousette Lundgren G, Wickström A, Hasselblad T, Dahllöf G. Amelogenesis imperfecta and early restorative crown therapy: an interview study with adolescents and young adults on their experiences. PLoS One. 2016;11(6):e0156879.Seymen F, Kiziltan B. Amelogenesis imperfecta: a scanning electron microscopic and histopathologic study. J Clin Pediatr Dent. 2002;26(4):327-35.Gilchrist F, Rodd H, Deery C, Marshman Z. Assessment of the quality of measures of child oral health-related quality of life. BMC Oral Health. 2014;14:40.Pousette Lundgren G, Karsten A, Dahllöf G. Oral health-related quality of life before and after crown therapy in young patients with amelogenesis imperfecta. Health Qual Life Outcomes. 2015;13:197.Toksavul S, Ulusoy M, Türkün M, Kümbüloğlu O. Amelogenesis imperfecta: the multidisciplinary approach. A case report. Quintessence Int. 2004;35(1):11-4.Greenfield R, Iacono V, Zove S, Baer P. Periodontal and prosthodontic treatment of amelogenesis imperfecta: a clinical report. J Prosthet Dent. 1992;68(4):572-74.Coffield KD, Phillips C, Brady M, Roberts MW, Strauss RP, Wright JT. The psychosocial impact of developmental dental defects in people with hereditary amelogenesis imperfecta. J Am Dent Assoc. 2005;136(5):620-30.

Background Vacuolar protein sorting-associated protein 4B (VPS4B) is a member of the ATP enzyme AAA protein family, and is mainly involved in protein degradation and cell membrane fusion. Recently, a dominant mutation in this gene was identified in human dentin dysplasia type I (DD-I). Herein, we report the generation of Vps4b knockout (Vps4b KO) mice; however, the homozygous Vps4b KO mutation was embryonic lethal at the early stages of embryo development, and we therefore report the results of heterozygous mutant mice. Results Mice heterozygous for Vps4b did not develop tooth defects replicating human DD-I. Immunohistochemistry showed that gene KO was successful, as there was decreased expression of Vps4b in heterozygous mice; hematoxylin and eosin (H&E) staining also showed that the width of the pre-dentin zone was increased in heterozygous mice, although the arrangement of the odontoblasts was not significantly different from wild-type (WT) mice. However, H&E staining showed no obvious abnormalities in the bones of heterozygous mice. Moreover, stereomicroscopic and X-ray radiography results indicated no abnormal manifestations in teeth or bones. Furthermore, statistical analysis of the volume and density of dentin and enamel, as well as skeletal analysis, including the volume and separation of trabecular bone analyzed by micro-CT, all showed no differences between Vps4b heterozygotes and WT mice. In addition, there also were no significant differences in bone or cartilage mineralization as evaluated by Alcian blue–Alizarin red staining. Conclusions The heterozygous Vps4b KO mice do not develop tooth defects that replicate human DD-I and this is likely to be due to differences in tooth development between the two species. Consequently, further studies are needed to determine whether mice are an appropriate animal model for human tooth diseases.

Dental development is a process by which several genes participate. These genes can be thus characterized as having a multifactorial, or complex, mode of inheritance. The identification of these processes was accelerated by the identification of gene mutations which can explain amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia. This knowledge has been applied to the study of conditions that are multifactorial in nature such as dental caries (both incipient lesions in enamel and deep lesions extending into dentin), enamel hypoplasia (in particular, molar-incisor hypomineralization), erosive tooth wear, and fluorosis.

Dentinogenesis imperfecta and dentin dysplasia are genetic abnormalities that have been described since the beginning of the 20th century. The clinical and radiographic features of these abnormalities are widely identified, but few studies describe their dentinal and enamel structure. However, as part of the therapeutic process and in the current context of restorative and adhesive dentistry, the question of the structural characteristics of the affected teeth arises due to the close relationship between bonding and dental structures. Through a systematic review of the literature, this thesis provides a survey of our knowledge of dentinal and enamel structures of the affected teeth in temporary and permanent dentition. After the analysis of 11 articles that met the inclusion criteria, defects have been revealed in dentinal structure but also in enamel structure (hypomineralization, structural defects, etc.) and in dentino-enamel junction (lack of scalloping, etc.). Thus, despite the publication of clinical cases that describe affected teeth treated by adhesive techniques with encouraging results over a longer or shorter period of time, the quality of adhesion to these dental surfaces remains open to discussion., Les dentinogenèses imparfaites et les dysplasies dentinaires sont des anomalies génétiques décrites depuis le début du XXème siècle. Leurs caractéristiques cliniques et radiographiques sont largement recensées mais peu d’études sont retrouvées sur la description de leurs structures dentinaire et amélaire. Or, dans une démarche thérapeutique de ces dents atteintes et au vu du développement de la dentisterie restauratrice adhésive avec ses principes de collage, la question des caractéristiques structurelles des dents atteintes se pose car ce collage est intimement lié aux structures dentaires. Par cette revue systématique de la littérature, cette thèse d’exercice a pour objectif de recenser les connaissances actuelles sur les structures amélaire et dentinaire des dents atteintes par ces pathologies dentinaires en denture temporaire et permanente. Elle met en avant, après analyse de 11 articles répondant aux critères d’inclusion de la revue systématique, des défauts de la dentine mais également de l’émail (hypominéralisations, défauts de structure…) et de la jonction amélo-dentinaire (manque de festonnement…). Ainsi, malgré la publication dans la littérature de cas clinique présentant des dents atteintes traitées par des techniques faisant appel au collage qui présentent des résultats encourageants à plus ou moins long terme, la qualité d’adhésion à ces surfaces dentaires reste discutable.

Dentin Dysplasia (DD) is a rare autosomal dominant anomaly that disturbs the formation of dentin in primary and/or permanent dentitions. This condition is classified into types I (radicular) and II (coronal) based on radiological findings. A case of DD type I in an 11-year old Iranian boy is presented and the clinical and radiological findings and selected treatment plan are discussed.

Dentin dysplasia type I (DDI) is an autosomal-dominant genetic disorder resulting from dentin defects. The molecular basis of DDI remains unclear. DDI exhibits unique characteristics with phenotypes featuring obliteration of pulp chambers and diminutive root, thus providing a useful model for understanding the genetics of tooth formation. Using a large Chinese family with 14 DDI patients, we mapped the gene locus responsible for DDI to 3p26.1-3p24.3 and further identified a missense mutation, c.353C>A (p.P118Q) in the SSUH2 gene on 3p26.1, which co-segregated with DDI. We showed that SSUH2 (p.P118Q) perturbed the structure and significantly reduced levels of mutant (MT) protein and mRNA compared with wild-type SSUH2. Furthermore, MT P141Q knock-in mice (+/- and -/-) had a unique partial obliteration of the pulp cavity and upregulation or downregulation of six major genes involved in odontogenesis: Dspp, Dmp1, Runx2, Pax9, Bmp2, and Dlx2. The phenotype of missing teeth was determined in zebrafish with morpholino gene knockdowns and rescued by injection of normal human mRNA. Taken together, our observations demonstrate that SSUH2 disrupts dental formation and that this novel gene, together with other odontogenesis genes, is involved in tooth development.

Secreted WNT proteins control cell differentiation and proliferation in many tissues, and NOTUM is a secreted enzyme that modulates WNT morphogens by removing a palmitoleoylate moiety that is essential for their activity. To better understand the role this enzyme in development, the authors produced NOTUM-deficient mice by targeted insertional disruption of the Notum gene. The authors discovered a critical role for NOTUM in dentin morphogenesis suggesting that increased WNT activity can disrupt odontoblast differentiation and orientation in both incisor and molar teeth. Although molars in Notum-/-mice had normal-shaped crowns and normal mantle dentin, the defective crown dentin resulted in enamel prone to fracture during mastication and made teeth more susceptible to endodontal inflammation and necrosis. The dentin dysplasia and short roots contributed to tooth hypermobility and to the spread of periodontal inflammation, which often progressed to periapical abscess formation. The additional incidental finding of renal agenesis in some Notum-/-mice indicated that NOTUM also has a role in kidney development, with undiagnosed bilateral renal agenesis most likely responsible for the observed decreased perinatal viability of Notum-/-mice. The findings support a significant role for NOTUM in modulating WNT signaling pathways that have pleiotropic effects on tooth and kidney development.

Tumoral calcinosis is a rare familial disorder characterized by masses of calcification in periarticular soft tissues. Few reports in the literature have described dental abnormalities in patients with tumoral calcinosis. These dental abnormalities include short bulbous roots, pulp stones, and obliteration of the pulp cavity. In this case report, we describe the dental radiographic findings in a patient with tumoral calcinosis; these findings were similar to dentin dysplasia. Periapical radiolucencies with noncarious teeth were observed in addition to the dental findings previously reported.

Introduction: Turner's hypoplasia is classified as acquired dental dysplasia (dysplasia dentales acquisitae). Turner's hypoplasia is a localized tooth dysplasia. Most often one of the permanent teeth is affected, but a group of adjacent permanent teeth may also be affected. Case Description : The survey was conducted in 2018/2019. It was conducted at the Faculty of Dental Medicine and the clinical offices of Pediatric Dental Medicine, Varna, Bulgaria. In order to conduct the study, we obtained informed consent from the parents of the patient, who is a child at 11 years of age. We have diagnosed Turner's hypoplasia on teeth 11, 12 and 21. The presence of hypoplastic and hypomineralized areas of the enamel of the occlusal 1/3 of the permanent incisor crowns affecting the cutting edges. Tooth 22 is with hypodontia dentis. Discussion : Turner's hypoplasia is an anomaly found in the structure of permanent teeth. Its appearance is variable, although it usually manifests as part of missing or reduced enamel on permanent teeth. Conclusion/clinical significance : A traumatic accident during childhood is the etiological reason for the development of Turner's hypoplasia on permanent teeth 11, 12, 21. Enamel hypoplasia has different variations and studies can be conducted to conclusion of their family habits.

Dentin dysplasia (DD) is a rare autosomal dominant disorder of dentin development, which is generally divided into two types based on the clinical and radiographic appearance of the affected dentinal tissues: Type-I (Radicular DD) and Type-II (Coronal DD). This paper reports the case of a 17-year-old female patient with both classical and atypical features of radicular DD in the permanent dentition. The present case shows clinically normal appearing crowns, localised mobility in the maxillary teeth, completely obliterated pulp chambers, widened root canals without any obliterations and the presence of multiple periapical radiolucencies. The clinical and radiographic findings observed in this present case report are different from those reported in the past literature, which suggests that the present case could be a variation of radicular DD.

Background Dentinogenesis imperfecta (DGI) is a heritable disorder of dentin. Genetic analyses have found two subgroups in this disorder: DGI type I, a syndromic form associated with osteogenesis imperfecta (OI), and DGI type II, a non-syndromic form. The differential diagnosis between types I and II is often challenging. Thus, the present cross-sectional study had two aims: to (i) investigate the prevalence and incidence of DGI type II among Swedish children and adolescents and (ii) search out undiagnosed cases of DGI type I by documenting the prevalence of clinical symptoms of OI in these individuals. We invited all public and private specialist pediatric dental clinics (n = 47) in 21 counties of Sweden to participate in the study. We then continuously followed up all reported cases during 2014−2017 in order to identify all children and adolescents presenting with DGI type II. Using a structured questionnaire and an examination protocol, pediatric dentists interviewed and examined patients regarding medical aspects such as bruising, prolonged bleeding, spraining, fractures, hearing impairment, and family history of osteoporosis and OI. Joint hypermobility and sclerae were assessed. The clinical oral examination, which included a radiographic examination when indicated, emphasized dental variables associated with OI. Results The prevalence of DGI type II was estimated to be 0.0022% (95% CI, 0.0016–0.0029%) or 1 in 45,455 individuals. Dental agenesis occurred in 9% of our group. Other findings included tooth retention (17%), pulpal obliteration (100%), and generalized joint hypermobility (30%). Clinical and radiographic findings raised a suspicion of undiagnosed OI in one individual, a 2-year-old boy; he was later diagnosed with OI type IV. Conclusions These results show a significantly lower prevalence of DGI type II than previously reported and point to the importance of excluding OI in children with DGI. Electronic supplementary material The online version of this article (10.1186/s13023-018-0887-2) contains supplementary material, which is available to authorized users.

According to their phenotypic features, the hereditary dentin defects in humans are categorized in two major classes: dentinogenesis imperfecta and dentin dysplasia. At its turn, the dentin dysplasia is subdivided in dentin dysplasia type I and dentin dysplasia type II, a milder clinical manifestation of the condition. Here we report the clinical and radiographic findings of dentin dysplasia type II in two members of a family, a young adult female and her mother. Except a mild shade change of the incisal margins in upper central incisors and left upper canine of the daughter no abnormal occlusal wear or crown shape change of the teeth were disclosed in both patients. However, confluent large pulp stones in the thistle-tube shaped pulp chambers and pulpal obliteration were a common finding. The condition was diagnosed as dentin dysplasia type II.

Nonsyndromic dentin defects classified as type II dentin dysplasia and types II and III dentinogenesis imperfecta are caused by mutations in DSPP (dentin sialophosphoprotein). Most reported disease‐causing DSPP mutations occur within the repetitive DPP (dentin phosphoprotein) coding sequence. We characterized the DPP sequences of five probands with inherited dentin defects using single molecule real‐time (SMRT) DNA sequencing. Eight of the 10 sequences matched previously reported DPP length haplotypes and two were novel. Alignment with known DPP sequences showed 32 indels arranged in 36 different patterns. Sixteen of the 32 indels were not represented in more than one haplotype. The 25 haplotypes with confirmed indels were aligned to generate a tree that describes how the length variations might have evolved. Some indels were independently generated in multiple lines. A previously reported disease‐causing DSPP mutation in Family 1 was confirmed and its position clarified (c.3135delC; p.Ser1045Argfs*269). A novel frameshift mutation (c.3504_3508dup; p.Asp1170Alafs*146) caused the dentin defects in Family 2. A COL1A2 (c.2027G>A or p.Gly676Asp) missense mutation, discovered by whole‐exome sequencing, caused the dentin defects in Family 3. We conclude that SMRT sequencing characterizes the DPP repeat region without cloning and can improve our understanding of normal and pathological length variations in DSPP alleles.

Dentin dysplasia type I (DD-I) is a rare human dentin disorder that may affect both the primary and permanent dentitions. The teeth present crowns with normal morphology but short or absent roots. Pulp chamber obliteration and early exfoliation of primary teeth are also observed. We describe herein the typical and atypical features of DD-I presented by a 6-year-old patient, the diagnostic rationale and assessment emphasizing the histological and scanning electron microscopic analysis and the therapeutic approach. The DD-I diagnosis in patients in the mixed dentition period is challenging, especially when only some teeth are affected.

Hereditary dentin disorders include dentinogenesis imperfecta (DGI) and dentin dysplasia (DD), which are autosomal dominant diseases characterized by altered dentin structure such as abnormality in dentin mineralization and the absence of root dentin. Shields classified DGI into three subgroups and DD into two subtypes. Although they are all hereditary dentin diseases, they do not share the same causative genes. To date, the pathogenic genes of DGI type I, which is considered a clinical manifestation of syndrome osteogenesis imperfecta, include COL1A1 and COL1A2. Mutations of the DSPP gene, which encodes the dentin sialophosphoprotein, a major non-collagenous protein, are responsible for three isolated dentinal diseases: DGI-II, DGI-III, and DD-II. However, DD-I appears to be special in that researchers have found three pathogenicity genes-VPS4B, SSUH2, and SMOC2-in three affected families from different countries. It is believed that DD-I is a genetically heterogeneous disease and is distinguished from other types of dentin disorders. This review summarizes the DD-I literature in the context of clinical appearances, radiographic characteristics, and functions of its pathogenic genes and aims to serve clinicians in further understanding and diagnosing this disease.

BACKGROUND: Dentinogenesis imperfecta (DI) is a rare debilitating hereditary disorder affecting dentin formation and causing loss of the overlying enamel. Clinically, DI sufferers have a discolored and weakened dentition with an increased risk of fracture. The aims of this study were to assess genotype-phenotype findings in three families with DI-II with special reference to mutations in the DSPP gene and clinical, histological, and imaging manifestations.METHODS: Nine patients participated in the study (two from family A, four from family B, and three from family C). Buccal swab samples were collected from all participants and extracted for genomic DNA. Clinical and radiographic examinations had been performed longitudinally, and the dental status was documented using photographic images. Four extracted and decalcified tooth samples were prepared for histological analysis to assess dysplastic manifestations in the dentin. Optical coherence tomography (OCT) was applied to study the health of enamel tissue from in vivo images and the effect of the mutation on the function and structure of the DSPP gene was analyzed using bioinformatics software programs.RESULTS: The direct DNA sequence analysis revealed three distinct mutations, one of which was a novel finding. The mutations caused dominant phenotypes presumably by interference with signal peptide processing and protein secretion. The clinical and radiographic disturbances in the permanent dentition indicated interfamilial variability in DI-II manifestations, however, no significant intrafamilial variability was observed.CONCLUSION: The different mutations in the DSPP gene were accompanied by distinct phenotypes. Enamel defects suggested deficit in preameloblast function during the early stages of amelogenesis.

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.

Dentin dysplasia, a rare hereditary disorder of dentin formation, is characterized by normal enamel but atypical dentin formation along with abnormal pulpal morphology. It is inherited as an autosomal dominant trait. It has been divided into two clinical entities: type I (radicular) and type II (coronal). Early diagnosis and initiation of effective regular dental treatments may help the patients with this condition to delay or prevent the loss of the entire dentition and help them in cope up with edentulous state in early ages. The condition undoubtedly has a negative impact on the physical and psychological well-being of the affected individual. Numerous factors have to be considered during the prosthetic rehabilitation of patients with dentin dysplasia. Treatment protocol varies according to clinical case. Although literature reports suggest general guidelines for treatment planning, the present case report describes a full mouth rehabilitation of an 8-year-old female patient with dentin dysplasia. How to cite this article: Khandelwal S, Gupta D, Likhyani L. A Case of Dentin Dysplasia with Full Mouth Rehabilitation: A 3-year Longitudinal Study. Int J Clin Pediatr Dent 2014;7(2): 119-124.

Context.— Some dental abnormalities have environmental causes. Other odontogenic alterations are idiopathic and may have hereditary etiologies. Investigations of these conditions are ongoing.Objective.— —To provide a discussion of developmental odontogenic abnormalities and benign odontogenic overgrowths and neoplasms for which genetic alterations have been well demonstrated and well documented.Data Sources.— Relevant peer-reviewed literature.Conclusions.— —The understanding of benign odontogenic lesions at a molecular level is rather well developed for some lesions and at the initial stages for many others. Further characterization of the molecular underpinnings of these and other odontogenic lesions would result in an enhanced comprehension of odontogenesis and the pathogenesis of a variety of odontogenic aberrations. These advancements may lead to better prevention and treatment paradigms and improved patient outcomes.

Dentinogenesis imperfecta and dentin dysplasia are two common types of genetic oral diseases resulted from the aberrant differentiation of odontoblast. Understanding the mechanisms of odontoblast differentiation is crucial for finding the diagnosis candidate genes and treatment targets for such kinds of diseases. Previous work has identified a battery of transcription factors and growth factors regulating odontoblast differentiation; however, the post-transcriptional regulating mechanisms of them are poorly studied. MicroRNAs (miRNA) are a group of non-coding RNAs widely studied in organ development, inflammation, and tumorigenesis because of its inhibitory effects on the target mRNAs. Also, miRNAs along with their binding targets form a complex competing endogenous RNA (ceRNA) network where miRNAs serve as the fine tuning balancers between their targets. Recent reports demonstrated the essential role of the miRNA pathway in dentinogenesis and the regulatory role of several specific miRNAs in the in vitro model of odontoblast differentiation. Herein, we will discuss the general roles of miRNA in diseases, the function of miRNAs during odontoblast differentiation, and finally the potential pathological mechanisms through which miRNAs cause the odontoblast-related diseases.

Dentin dysplasia is a rare hereditary disturbance characterized by a dental anomaly of the dentin layer. The etiology is unclear, and this rare hereditary disturbance affects approximately one person in every 100,000. Dentin dysplasia is classified into two types, radicular dentin dysplasia as type I and coronal dentin dysplasia as type II. The characteristic clinical findings of dentin dysplasia type I are normal appearance of the crown and hypermobility of teeth. The radiographic findings are obliteration of all pulp canals, short, blunted and malformed or absent roots. Dentin dysplasia type II as coronal dentin dysplasia shows similar clinical features with dentinogensis imperfecta. This report shows a case of dentin dysplasia type I affecting one family except the father. The clinical, radiographic and histopathologic findings of this family are presented. Dentin dysplasia type I is difficult to diagnose unless dentist performs radiographic examination. If the affecting patient does not get regular dental care, dental abscesses or cysts may form spontaneously without caries. In this regard, early diagnosis is important to prevent premature loss of dentition.

Dentin dysplasia (DD) is an uncommon developmental disturbance affecting dentin, resulting in enamel with atypical dentin formation and abnormal pulpal morphology. Type I (radicular) and Type II (coronal) are the two types of DD. Type I is more common, and both types include single or multiple teeth in primary and permanent dentition. Combinations of both types have also been described in literature. Four distinct forms of Type I and one form of Type II were identified. This case report documents one such rarity of DD in an 11-year-old female with clinical and radiographical findings and management aspects.

Streszczenie Wprowadzenie. Dentinogenesis imperfecta typu II (DGI) oraz dysplazja zebiny (DD) są rzadkimi, izolowanymi wrodzonymi wadami rozwojowymi polegającymi na nieprawidlowym formowaniu zebiny zarowno w zebach mlecznych jak i stalych. Poza istotną zmianą koloru zebow dochodzi do ich szybkiego starcia, a nastepnie utraty. Leczenie zachowawcze jak i protetyczne pacjentow chorujących na DGI/DD niejednokrotnie jest nieskuteczne. Przy planowaniu leczenia pacjentow z DGI/DD niezbednym jest potwierdzenie rozpoznania metodami diagnostyki molekularnej. Za fenotyp DGI/DD odpowiedzialne są mutacje w genie DSPP, ktory wykazuje wysoki stopien polimorfizmu oraz posiada dlugie sekwencje repetywne, co utrudnia jego sekwencjonowanie. Cel pracy. Analiza molekularna genu DSPP u przypadkowych osob nie wykazujących cech klinicznych fenotypu dentinogenesis imperfecta typu II bądź dysplazji zebiny. Mutacje w genie kodującym bialko sialofosforowe zebiny (DSPP) nie zawsze skutkujące fenotypem dentinogenesis imperfecta typu II bądź dysplazją zebiny*

Dentin dysplasia is a rare inherited autosomal dominant disorder characterized by rootless teeth. We hereby report a case of dentin dysplasia type 1b with typical radiographic findings: short and blunt roots, pulpal obliteration, horizontal/crescent shaped radiolucencies in pulp chambers, and multiple periapical radiolucencies. However, the present case did not show the autosomal dominant pattern of inheritance and the patient also exhibited concurrent dental fluorosis, transposition of 13 and 14, and multiple cusps in maxillary first molars. Moreover, on careful review of previously documented cases of radiographs of dentin dysplasia, the horizontal/crescent shaped radiolucencies in pulp chambers are a rare finding, which is characteristically seen in the present case.

Objectives Amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia are the most common non-syndromic dental disorders. In this study, we analysed and localised the gene(s) responsible for inherited non-syndromic dental disorders in a Chinese family. Methods This study identified and researched non-syndromic dental disorders in a four-generation Chinese family, including four affected individuals whose clinical phenotype was atypical. Linkage analysis with seven polymorphic markers that localise to six different autochromosomes showed that the family was linked through chromosome 4q. All exons and exon–intron boundaries of dentin sialophosphoprotein (DSPP), enamelin (ENAM), and ameloblastin (AMBN), which are located on chromosome 4q, were sequenced in nine of the family members. Results Direct DNA sequence analysis revealed the existence of a G to A transversion in exon 4 (g.13081786G > A, c.727G > A, p.Asp243Asn, based on reference sequences NM_014208.3 ) of the DSPP gene, and this sequence variation correlated exactly with the presence of the disease. Conclusion These results indicate that mutation p.Asp243Asn is a highly probable cause of non-syndromic dental disorder in this Chinese family. The presence of symptom heterogeneity is possible, as the clinical classification system is hampered by the lack of close correlation between the subtype and the molecular defect.

BACKGROUND: Orodental diseases include several clinically and genetically heterogeneous disorders that can present in isolation or as part of a genetic syndrome. Due to the vast number of genes implicated in these disorders, establishing a molecular diagnosis can be challenging. We aimed to develop a targeted next-generation sequencing (NGS) assay to diagnose mutations and potentially identify novel genes mutated in this group of disorders. METHODS: We designed an NGS gene panel that targets 585 known and candidate genes in orodental disease. We screened a cohort of 101 unrelated patients without a molecular diagnosis referred to the Reference Centre for Oro-Dental Manifestations of Rare Diseases, Strasbourg, France, for a variety of orodental disorders including isolated and syndromic amelogenesis imperfecta (AI), isolated and syndromic selective tooth agenesis (STHAG), isolated and syndromic dentinogenesis imperfecta, isolated dentin dysplasia, otodental dysplasia and primary failure of tooth eruption. RESULTS: We discovered 21 novel pathogenic variants and identified the causative mutation in 39 unrelated patients in known genes (overall diagnostic rate: 39%). Among the largest subcohorts of patients with isolated AI (50 unrelated patients) and isolated STHAG (21 unrelated patients), we had a definitive diagnosis in 14 (27%) and 15 cases (71%), respectively. Surprisingly, COL17A1 mutations accounted for the majority of autosomal-dominant AI cases. CONCLUSIONS: We have developed a novel targeted NGS assay for the efficient molecular diagnosis of a wide variety of orodental diseases. Furthermore, our panel will contribute to better understanding the contribution of these genes to orodental disease. TRIAL REGISTRATION NUMBERS: NCT01746121 and NCT02397824. journal article research support, non-u.s. gov't 2016 Feb 2015 10 26 imported

The last research of calcified tissue like bones and teeth has provided new information with regard to the genetic factors that control the formation of these tissues. The environmental factors like stress, different diet, long range mobility, and health of an individual can be also recorded in the skeleton and teeth. Dentin may be affected by morbid conditions present during development and, like enamel, may be affected by processes after eruption. Dentin dysplasia is one of the congenital disorders of mineralized tooth tissues. It is characterized by dentin abnormality. The pathological conditions affecting teeth have for reconstructing important aspects of the health of past human groups. The aim of the paper was to present the clinical manifestation of dentin dysplasia to get better acquainted with characteristic abnormalities in dentin which can be also used in paleodontology research. Despite many reports and descriptions of cases of patients with dentin dysplasia, etiology, diagnosis and treatment of this disease remain unclear so far but with a help of radiological characteristic image the correct differentiation and recognition is crucial. Another important point is proper and detailed documentation which can be also helpful in the future long term observation.