RESUMO
The LRP5 gene encodes a Wnt signaling receptor to which Wnt binds directly. In humans, pathogenic monoallelic variants in LRP5 have been associated with increased bone density and exudative vitreoretinopathy. In mice, LRP5 plays a role in tooth development, including periodontal tissue stability and cementum formation. Here, we report a 14-year-old patient with a de novo non-synonymous variant, p.(Val1245Met), in LRP5 who exhibited mildly reduced bone density and mild exudative vitreoretinopathy together with a previously unreported phenotype consisting of dental abnormalities that included fork-like small incisors with short roots and an anterior open bite, molars with a single root, and severe taurodontism. In that exudative vitreoretinopathy has been reported to be associated with heterozygous loss-of-function variants of LRP5 and that our patient reported here with the p.(Val1245Met) variant had mild exudative vitreoretinopathy, the variant can be considered as an incomplete loss-of-function variant. Alternatively, the p.(Val1245Met) variant can be considered as exerting a dominant-negative effect, as no patients with truncating LRP5 variants and exudative vitreoretinopathy have been reported to exhibit dental anomalies. The documentation of dental anomalies in the presently reported patient strongly supports the notion that LRP5 plays a critical role in odontogenesis in humans, similar to its role in mice.
Assuntos
Dentes Fusionados/genética , Incisivo/patologia , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Adolescente , Animais , Densidade Óssea/genética , Dentes Fusionados/diagnóstico por imagem , Dentes Fusionados/patologia , Humanos , Incisivo/diagnóstico por imagem , Mutação com Perda de Função/genética , Masculino , Camundongos , Mutação , Fenótipo , Via de Sinalização Wnt/genéticaRESUMO
Double and congenitally missing teeth are known to be commoner in the primary dentition than the permanent. The knowledge of this trait in the permanent dentition in Africa is still poor. This paper describes the clinical findings in a pair of monozygotic Nigerian twins. This illustrates the claims of genetic basis of such conditions, which have been reported severally in developed parts of the globe but not much among the indigenous Nigerian Negroid population especially involving the permanent dentition.
Assuntos
Anodontia/genética , Dentição Permanente , Dentes Fusionados/genética , Incisivo/anormalidades , Gêmeos Monozigóticos , Criança , Feminino , Humanos , NigériaRESUMO
Double teeth are not really rare, but it is still enigmatic why and how they develop. Based upon the clinical, morphological and anatomical appearance and the number of teeth in mouths with double teeth, the double teeth are labelled as products of 'fusion' and 'clefting', but the criteria to attach such etiological names are lacking. It is assumed that heredity is involved in the development of double teeth. Therefore it is attempted to explain why only one of a homozygotic twin had a double tooth.
Assuntos
Dentes Fusionados/etiologia , Dente Decíduo/anormalidades , Pré-Escolar , Dentes Fusionados/epidemiologia , Dentes Fusionados/genética , Humanos , Masculino , Países Baixos/epidemiologia , Prevalência , Dente Supranumerário , GêmeosRESUMO
Double primary teeth occur in a sample of children from western India at a prevalence rate of 1.5 percent with no sex predilection, typically occurring unilaterally, and without preference for involvement of the central incisor and lateral incisor or the lateral incisor and canine. A higher incidence of fusion over gemination was also found. An examination of the world-wide distribution of the trait suggests European and European-derived populations exhibit universally low incidences, while Asian and Asian-derived populations exhibit relatively higher frequencies. The intermediate incidence reported for western India is in agreement with previous findings with primary dental morphology, suggesting an intermediate genetic affiliation between Asian and European samples.
Assuntos
Dentes Fusionados/epidemiologia , Pré-Escolar , Dente Canino/anormalidades , Feminino , Dentes Fusionados/genética , Humanos , Incisivo/anormalidades , Índia/epidemiologia , Lactente , Masculino , Prevalência , Grupos Raciais/genética , Dente Decíduo/anormalidadesRESUMO
The relationship between fusion of the permanent maxillary right central incisor to a supernumerary tooth in association with gemination of permanent maxillary left central incisor and dermatoglyphics were investigated.
Assuntos
Dentes Fusionados/complicações , Incisivo/anormalidades , Dente Supranumerário/complicações , Adolescente , Dermatoglifia , Dentes Fusionados/genética , Humanos , Masculino , Linhagem , Dente Supranumerário/genéticaRESUMO
This case report contains the dental, genetic and dermatoglyphic findings of a patient showing bilateral maxillary central incisors fused to an extra one and his paternal uncle having macrodontia of central incisor teeth.
Assuntos
Dermatoglifia , Dentes Fusionados/genética , Incisivo/anormalidades , Dente Supranumerário/genética , Adulto , Dentes Fusionados/complicações , Humanos , Lactente , Masculino , Maxila , Linhagem , Dente Decíduo/anormalidades , Dente Supranumerário/complicaçõesRESUMO
A pair of monozygotic twins had similar but not identical dental anomalies. One twin had fusion of deciduous mandibular lateral incisor and canine on the left, with normal dentition on the right; the co-twin had right mandibular incisor/canine fusion, with aplasia of the lateral incisor on the left. These findings are discussed in the context of the related phenomena of situs inversus, mirror-imaging in twins, and gradients of severity of anomalies in the four copies of the mandibular developmental dental field.
Assuntos
Doenças em Gêmeos/genética , Dentes Fusionados/genética , Gêmeos Monozigóticos/genética , Anodontia/genética , Pré-Escolar , Dente Canino/anormalidades , Feminino , Humanos , Incisivo/anormalidades , MandíbulaRESUMO
There is now considerable evidence to support the theory that heredity is the origin of this anomaly. The condition in one of the twins described here was the mirror image of the condition of the other.
Assuntos
Anodontia/genética , Doenças em Gêmeos , Dentes Fusionados/genética , Incisivo/anormalidades , Anormalidades Dentárias/genética , Dente Supranumerário/genética , Gêmeos Monozigóticos , Gêmeos , Pré-Escolar , Humanos , MasculinoRESUMO
A case report of fused teeth in two of five siblings is described. Both siblings had fusion of contralateral lower primary canines and lateral incisors. One had aplasia of one of the succedaneous lateral incisors.
Assuntos
Dente Canino/anormalidades , Dentes Fusionados/genética , Incisivo/anormalidades , Anormalidades Dentárias/genética , Criança , Pré-Escolar , Feminino , Humanos , MasculinoAssuntos
Doenças em Gêmeos , Dentes Fusionados/genética , Anormalidades Dentárias/genética , Gêmeos Monozigóticos , Gêmeos , Pré-Escolar , Feminino , Humanos , Masculino , GravidezRESUMO
The study was done to determine the incidence and distribution of root fusion in 1340 maxillary and mandibular molars in 170 patients. A second objective was to determine whether root fusion of molars is sex-linked. A substantial percentage, 29% of all molars, had fused roots. Root fusion was found more frequently in maxillary than mandibular molars, 35% to 24%, and it occurred in many patients, rather than being limited to a few. Root fusion was most common in third molars, followed by second molars, in both jaws. It occurred in almost equal numbers in corresponding molars of opposite sides, approaching bilateral symmetry. The proportion of molars with root fusion was approximately 5% greater in females than in males, and about 13% more females had molar root fusion than males.
