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1.
Int Endod J ; 55(10): 1091-1102, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35833329

RESUMO

AIM: The use of high-concentration sodium hypochlorite (NaOCl) as an endodontic irrigant remains controversial because of its potential impact on the fracture strength of endodontically treated teeth. This study evaluated the effects of using different NaOCl concentrations, with 2-min-ethylenediaminetetraacetic acid (EDTA) as the final active irrigant, on the biomechanical and structural properties of root dentine. METHODOLOGY: A new test method, which is more clinically relevant, was utilized to calculate the fracture strength of root dentine. Bovine incisors were used to obtain root dentine discs. The root canals were enlarged to mean diameter of 2.90 mm with a taper of 0.06. The resulting discs were divided into five groups (n = 20) and treated with different concentrations of NaOCl (5.25%, 2.5%, and 1.3%) for 30 min plus 17% EDTA for 2 min. The discs were then loaded to fracture by a steel rod with the same taper through the central hole. The fractured specimens were examined by scanning electron microscopy to evaluate changes in the dimensions of the remaining intertubular dentine and the tubular radius. Micro-hardness was also measured with a Knoop diamond indenter along a radius to determine the depth of dentine eroded by the irrigation. Results were analysed by one-way anova and the Tukey test. The level of significance was set at α = 0.05. RESULTS: The damage by NaOCl increased with its concentration. 5.25% NaOCl greatly reduced the fracture strength of root dentine from 172.10 ± 30.13 MPa to 114.58 ± 26.74 MPa. The corresponding reduction in micro-hardness at the root canal wall was 34.1%. The damages reached a depth of up to 400 µm (p < .05). Structural changes involved the degradation of the intratubular wall leading to enlarged dentinal tubules and the loss of intertubular dentine. Changes in the microstructural parameters showed positive linear relationships with the fracture strength. CONCLUSIONS: With the adjunctive use of EDTA, NaOCl caused destruction to the intratubular surface near the root canal and, consequently, reduced the root dentine's mechanical strength. The higher the concentration of NaOCl, the greater the effect. Therefore, endodontists should avoid using overly high concentration of NaOCl for irrigation to prevent potential root fracture in endodontically treated teeth.


Assuntos
Hipoclorito de Sódio , Dente não Vital , Animais , Bovinos , Cavidade Pulpar , Dentina , Ácido Edético/farmacologia , Humanos , Irrigantes do Canal Radicular/farmacologia , Preparo de Canal Radicular , Hipoclorito de Sódio/farmacologia
2.
Int Endod J ; 55(7): 772-783, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35383959

RESUMO

AIM: To evaluate the physicochemical properties of five root canal sealers and assess their effect on an ex vivo dental plaque-derived polymicrobial community. METHODOLOGY: Dental plaque-derived microbial communities were exposed to the sealers (AH Plus [AHP], GuttaFlow Bioseal [GFB], Endoseal MTA [ESM], Bio-C sealer [BCS] and BioRoot RCS [BRR]) for 3, 6 and 18 h. The sealers' effect on the biofilm biomass and metabolic activity was quantified using crystal violet (CV) staining and MTT assay, respectively. Biofilm community composition and morphology were assessed by denaturing gradient gel electrophoresis (DGGE), 16S rRNA sequencing and scanning electron microscopy. The ISO6876:2012 specifications were followed to determine the setting time, radiopacity, flowability and solubility. Obturated acrylic teeth were used to assess the sealers' effect on pH. Surface chemical characterization was performed using SEM with coupled energy-dispersive spectroscopy. Data normality was assessed using the Shapiro-Wilk test. One-way anova and Tukey's tests were used to analyze data from setting time, radiopacity, flowability and solubility. Two-way anova and Dunnett's tests were used for the data analysis from CV, MTT and pH. 16S rRNA sequencing data were analyzed for alpha (Shannon index and Chao analysis) and beta diversity (Bray-Curtis dissimilarities). Differences in community composition were evaluated by analysis of similarity (p < .05). RESULTS: The sealers significantly influenced microbial community composition and morphology. All sealers complied with ISO6876:2012 requirements for setting time, radiopacity and flowability. Although only AHP effectively reduced the biofilm biomass, all sealers, except BRR, reduced biofilm metabolic activity. CONCLUSION: Despite adequate physical properties, none of the sealers tested prevented biofilm growth. Significant changes in community composition were observed. If observed in vivo, these changes could affect intracanal microbial survival, pathogenicity and treatment outcomes.


Assuntos
Placa Dentária , Materiais Restauradores do Canal Radicular , Biofilmes , Compostos de Cálcio/química , Cavidade Pulpar , Resinas Epóxi/química , Humanos , Teste de Materiais , RNA Ribossômico 16S , Materiais Restauradores do Canal Radicular/química , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/química
3.
Proc Natl Acad Sci U S A ; 113(51): 14633-14638, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27930344

RESUMO

Nanomaterial-based field-effect transistor (FET) sensors are capable of label-free real-time chemical and biological detection with high sensitivity and spatial resolution, although direct measurements in high-ionic-strength physiological solutions remain challenging due to the Debye screening effect. Recently, we demonstrated a general strategy to overcome this challenge by incorporating a biomolecule-permeable polymer layer on the surface of silicon nanowire FET sensors. The permeable polymer layer can increase the effective screening length immediately adjacent to the device surface and thereby enable real-time detection of biomolecules in high-ionic-strength solutions. Here, we describe studies demonstrating both the generality of this concept and application to specific protein detection using graphene FET sensors. Concentration-dependent measurements made with polyethylene glycol (PEG)-modified graphene devices exhibited real-time reversible detection of prostate specific antigen (PSA) from 1 to 1,000 nM in 100 mM phosphate buffer. In addition, comodification of graphene devices with PEG and DNA aptamers yielded specific irreversible binding and detection of PSA in pH 7.4 1x PBS solutions, whereas control experiments with proteins that do not bind to the aptamer showed smaller reversible signals. In addition, the active aptamer receptor of the modified graphene devices could be regenerated to yield multiuse selective PSA sensing under physiological conditions. The current work presents an important concept toward the application of nanomaterial-based FET sensors for biochemical sensing in physiological environments and thus could lead to powerful tools for basic research and healthcare.


Assuntos
Técnicas Biossensoriais/instrumentação , Grafite/química , Nanofios/química , Transistores Eletrônicos , Aptâmeros de Nucleotídeos/química , Desenho de Equipamento , Etanolamina/química , Humanos , Concentração de Íons de Hidrogênio , Masculino , Microscopia de Força Atômica , Nanoestruturas , Polietilenoglicóis/química , Polímeros/química , Antígeno Prostático Específico/sangue , Análise Espectral Raman , Propriedades de Superfície , Fatores de Tempo
4.
J Oral Pathol Med ; 47(9): 895-899, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29998466

RESUMO

OBJECTIVES: Mucocele of the minor salivary gland is usually caused when the duct is injured, mucus leaks into the tissue space and the mucous gland are obstructed, which lead to cystic lesion formation and dilatation. Currently, there are multiple therapeutic methods available with various outcomes. This study aims to provide clinical evidence of polidocanol sclerotherapy for the treatment of mucocele of the minor salivary gland. METHODS: In this study, we injected polidocanol into 112 patients who were diagnosed with mucocele of the minor salivary gland and evaluated the treatment efficacy and safety systematically. RESULTS: Of the 122 cases, 102 cases were cured, eight cases showed remarkable remission, and two cases had partial remission. No recurrence was found during follow-up, and none of the cases showed an invalid effect, resulting in a total cure rate of 91.07%. No severe side effects were observed during treatment or the follow-up period. No significant difference in efficacy between different genders was found (P = 0.490). Polidocanol sclerotherapy for mucocele on the lower lip was more effective compared to mucocele on the inferior surface of the lingual apex (P = 0.035). CONCLUSION: Polidocanol sclerotherapy showed satisfying curative effects for mucocele of the minor salivary gland without causing side effects of anesthesia, trauma, or severe pain.


Assuntos
Mucocele/terapia , Polidocanol/administração & dosagem , Glândulas Salivares Menores , Soluções Esclerosantes/administração & dosagem , Escleroterapia/métodos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
5.
Dent Mater ; 40(6): 889-896, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692997

RESUMO

OBJECTIVE: The current study aimed to evaluate the effects of different combinations of chemical and mechanical challenges on the failure load, failure mode and composition of the resulting fracture surfaces of resin-composite restorations. METHODS: Three resin composites were used to fill dentin disks (2 mm inner diameter, 5 mm outer diameter, and 2 mm thick) made from bovine incisor roots. The model restorations, half of which were preconditioned with a low-pH buffer (48 h under pH 4.5), were subjected to diametral compression with either a monotonically increasing load (fast fracture) or a cyclic load with a continuously increasing amplitude (accelerated fatigue). The load or number of cycles to failure was noted. SEM was performed on the fracture surfaces to determine the proportions of dentin, adhesive, and resin composite. RESULTS: Both cyclic fatigue and acid preconditioning significantly reduced the failure load and increased the proportion of interfacial failure in almost all the cases, with cyclic fatigue having a more pronounced effect. Cyclic fatigue also increased the amount of adhesive/hybrid layer present on the fracture surfaces, but the effect of acid preconditioning on the composition of the fracture surfaces varied among the resin composites. SIGNIFICANCE: The adhesive or hybrid layer was found to be the least resistant against the chemomechanical challenges among the components forming the model restoration. Increasing such resistance of the tooth-restoration interface, or its ability to combat the bacterial actions that lead to secondary caries following interfacial debonding, can enhance the longevity of resin-composite restorations.


Assuntos
Resinas Compostas , Falha de Restauração Dentária , Restauração Dentária Permanente , Análise do Estresse Dentário , Teste de Materiais , Resinas Compostas/química , Bovinos , Animais , Propriedades de Superfície , Microscopia Eletrônica de Varredura , Cimentos de Resina/química , Concentração de Íons de Hidrogênio , Dentina , Estresse Mecânico
6.
ACS Appl Mater Interfaces ; 16(25): 32702-32712, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38870327

RESUMO

Herein, we report a dual-functional flexible sensor (DFFS) using a magnetic conductive polymer composed of nickel (Ni), carbon black (CB), and polydimethylsiloxane (PDMS). The material selection for the DFFS utilizes the excellent elasticity of the PDMS matrix and the synergistic interaction between Ni and CB. The DFFS has a wide strain range of 0-170%, a high sensitivity of 74.13 (140-170%), and a low detection limit of 0.3% strain. The DFFS based on superior performance can accurately detect microstrain/microvibration, oncoming/contacting objects, and bicycle riding speed. Additionally, the DFFS can be used for comprehensive monitoring of human movements. Therefore, the DFFS of this work shows significant value for implementation in intelligent wearable devices and noncontact intelligent control.


Assuntos
Dimetilpolisiloxanos , Microesferas , Níquel , Fuligem , Dispositivos Eletrônicos Vestíveis , Dimetilpolisiloxanos/química , Humanos , Níquel/química , Fuligem/química , Movimento , Condutividade Elétrica
7.
ACS Macro Lett ; 12(3): 408-414, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36897173

RESUMO

Fibrillar collagen structures mineralized with hydroxyapatite using the polymer-induced liquid precursor (PILP) process have been explored as synthetic models for studying biomineralization of human hard tissues and have also been applied in the fabrication of scaffolds for hard tissue regeneration. Strontium has important biological functions in bone and has been used as a therapeutic agent for treating diseases that result in bone defects, such as osteoporosis. Here, we developed a strategy to mineralize collagen with Sr-doped hydroxyapatite (HA) using the PILP process. Doping with Sr altered the crystal lattice of HA and inhibited the degree of mineralization in a concentration-dependent manner, but did not affect the unique formation of intrafibrillar minerals using the PILP. The Sr-doped HA nanocrystals were aligned in the [001] direction but did not recapitulate the parallel alignment of the c-axis of pure Ca HA in relation to the collagen fiber long axis. The mimicry of doping Sr in PILP-mineralized collagen can help understand the doping of Sr in natural hard tissues and during treatment. The fibrillary mineralized collagen with Sr-doped HA will be explored in future work as biomimetic and bioactive scaffolds for regeneration of bone and tooth dentin.


Assuntos
Biomimética , Colágenos Fibrilares , Humanos , Hidroxiapatitas , Colágeno/química , Durapatita/química , Estrôncio/farmacologia
8.
Am J Transl Res ; 15(11): 6626-6631, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074820

RESUMO

De novo glomerular injuries or relapse of nephropathy following COVID-19 vaccine has been reported. Here we present the first case of successful treatment of new-onset diabetes mellitus and biopsy-proven IgA nephropathy after COVID-19 vaccination. A 56-year-old man with no known medical history of renal dysfunction or diabetes mellitus developed both within 3 months after receiving a third dose of inactivated COVID-19 vaccine (Vero cells). His symptoms were characterized by brown urine, severe dry mouth, and excessive thirst. Randomly acquired blood glucose levels exceeded 33.3 mmol/L. A kidney biopsy showed IgA nephropathy. He was started on insulin for glycemic control. After glucocorticoid and cyclophosphamide treatment, oral tablets of repaglinide, combined with acarbose, controlled blood glucose and stabilized kidney function. This case is unique because the kidneys and pancreas were simultaneously affected by the vaccine. Successful treatment of the disease proved that cyclophosphamide combined with glucocorticoids were effective and that blood glucose was successfully controlled. This treatment option could be useful in similar cases in the future.

9.
Sci Adv ; 9(32): eadi1870, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37556541

RESUMO

Multicellular biological systems, particularly living neural networks, exhibit highly complex organization properties that pose difficulties for building cell-specific biocompatible interfaces. We previously developed an approach to genetically program cells to assemble structures that modify electrical properties of neurons in situ, opening up the possibility of building minimally invasive cell-specific structures and interfaces. However, the efficiency and biocompatibility of this approach were challenged by limited membrane targeting of the constructed materials. Here, we design a method for highly localized expression of enzymes targeted to the plasma membrane of primary neurons, with minimal intracellular retention. Next, we show that polymers synthesized in situ by this approach form dense extracellular clusters selectively on the targeted cell membrane and that neurons remain viable after polymerization. Last, we show generalizability of this method across a range of design strategies. This platform can be readily extended to incorporate a broad diversity of materials onto specific cell membranes within tissues and may further enable next-generation biological interfaces.


Assuntos
Neurônios , Polímeros , Polímeros/química , Neurônios/fisiologia , Membrana Celular/metabolismo , Materiais Biocompatíveis/química
10.
Bioact Mater ; 6(8): 2250-2260, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33553813

RESUMO

Infection in hard tissue regeneration is a clinically-relevant challenge. Development of scaffolds with dual function for promoting bone/dental tissue growth and preventing bacterial infections is a critical need in the field. Here we fabricated hybrid scaffolds by intrafibrillar-mineralization of collagen using a biomimetic process and subsequently coating the scaffold with an antimicrobial designer peptide with cationic and amphipathic properties. The highly hydrophilic mineralized collagen scaffolds provided an ideal substrate to form a dense and stable coating of the antimicrobial peptides. The amount of hydroxyapatite in the mineralized fibers modulated the rheological behavior of the scaffolds with no influence on the amount of recruited peptides and the resulting increase in hydrophobicity. The developed scaffolds were potent by contact killing of Gram-negative Escherichia coli and Gram-positive Streptococcus gordonii as well as cytocompatible to human bone marrow-derived mesenchymal stromal cells. The process of scaffold fabrication is versatile and can be used to control mineral load and/or intrafibrillar-mineralized scaffolds made of other biopolymers.

11.
Mol Oral Microbiol ; 35(5): 211-221, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32794605

RESUMO

Csn2 is an important protein of the CRISPR-Cas system. The physiological function of this protein and its regulatory role in Streptococcus mutans, as the primary causative agent of human dental caries, is still unclear. In this study, we investigated whether csn2 deletion would affect S. mutans physiology and virulence gene expression. We used microscopic imaging, acid killing assays, pH drop, biofilm formation, and exopolysaccharide (EPS) production tests to determine whether csn2 deletion influenced S. mutans colony morphology, acid tolerance/production, and glucan formation abilities. Comparisons were made between quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) data from the UA159 and csn2 deletion strain to determine the impact of csn2 knockout on S. mutans gene expression. The results showed that deletion of S. mutans csn2 changed its colony morphotype and made it more sensitive to acid. The expression levels of aciduricity genes, including leuA, leuB, leuC, and leuD, were significantly down-regulated. Acid adaptation restored the aciduricity of csn2 mutant and enhanced the ability to synthesize EPS. The expression levels of EPS synthesis-related genes, including gtfC and gtfD, were significantly up-regulated after acid adaptation. In summary, deletion of S. mutans csn2 exerted multiple effects on the virulence traits of this pathogen, including acid tolerance and EPS formation, and that these alterations could partially be attributed to changes in gene expression upon loss of csn2. Understanding the function of csn2 in S. mutans might lead to novel strategies to prevent or treat imbalances in oral microbiota that may favor diseases.


Assuntos
Ácidos/farmacologia , Deleção de Genes , Genes Bacterianos , Polissacarídeos Bacterianos/biossíntese , Streptococcus mutans , Biofilmes , Sistemas CRISPR-Cas , Cárie Dentária , Humanos , Streptococcus mutans/genética , Streptococcus mutans/fisiologia , Virulência/genética
12.
Int J Oral Sci ; 12(1): 15, 2020 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-32385260

RESUMO

The oral microbial community is widely regarded as a latent reservoir of antibiotic resistance genes. This study assessed the molecular epidemiology, susceptibility profile, and resistance mechanisms of 35 methicillin-resistant Staphylococcus epidermidis (MRSE) strains isolated from the dental plaque of a healthy human population. Broth microdilution minimum inhibitory concentrations (MICs) revealed that all the isolates were nonsusceptible to oxacillin and penicillin G. Most of them were also resistant to trimethoprim (65.7%) and erythromycin (54.3%). The resistance to multiple antibiotics was found to be largely due to the acquisition of plasmid-borne genes. The mecA and dfrA genes were found in all the isolates, mostly dfrG (80%), aacA-aphD (20%), aadD (28.6%), aphA3 (22.9%), msrA (5.7%), and the ermC gene (14.3%). Classical mutational mechanisms found in these isolates were mainly efflux pumps such as qacA (31.4%), qacC (25.7%), tetK (17.1%), and norA (8.6%). Multilocus sequence type analysis revealed that sequence type 59 (ST59) strains comprised 71.43% of the typed isolates, and the eBURST algorithm clustered STs into the clonal complex 2-II(CC2-II). The staphyloccoccal cassette chromosome mec (SCCmec) type results showed that 25 (71.43%) were assigned to type IV. Moreover, 88.66% of the isolates were found to harbor six or more biofilm-associated genes. The aap, atlE, embp, sdrF, and IS256 genes were detected in all 35 isolates. This research demonstrates that biofilm-positive multiple-antibiotic-resistant ST59-SCCmec IV S. epidermidis strains exist in the dental plaque of healthy people and may be a potential risk for the transmission of antibiotic resistance.


Assuntos
Placa Dentária/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/diagnóstico , Staphylococcus epidermidis/isolamento & purificação , Antibacterianos/uso terapêutico , Feminino , Humanos , Meticilina
13.
Acta Biomater ; 109: 132-141, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32289496

RESUMO

Currently, resin composites are the most popular materials for dental restoration in clinical practice. Although the properties of such materials have been improved significantly, together with better clinical techniques used for their placement, early restoration failure still occurs too frequently. As clinical studies take years to complete, and new resin composites are being produced at ever increasing pace, laboratory assessment using accelerated but representative tests is necessary. The main types of failure in resin-composite restoration are tooth/restoration fracture and secondary caries, which are caused by a combination of mechanical and biochemical challenges. In this study, a biofilm model (S. mutans) and a chemical model (lactic-acid buffer) for producing artificial caries in bovine dentin are developed and calibrated against in situ data. Using a power law relationship between the demineralization depth and challenge duration, scale factors that convert the in vitro durations to the equivalent clinical durations are determined for different pH values for each model. The scale factors will allow the synchronization of biochemical and mechanical challenges in terms of their rates of action to potentially test resin-composite restoration in an accelerated but clinically representative manner. STATEMENT OF SIGNIFICANCE: Although the properties of resin composites for dental restoration have been improved significantly, early restoration failure still occurs too frequently. As clinical studies take years to complete, accelerated laboratory testing is necessary. Resin-composite restoration fail mainly through fracture and secondary caries, caused by a combination of mechanical and biochemical challenges. In this study, a biofilm and a chemical model for producing artificial caries in bovine dentin are calibrated against in situ data. Using a power law relationship between demineralization depth and challenge duration, scale factors are determined for different pH for each model. The scale factors will allow the synchronization of biochemical and mechanical challenges in testing resin-composite restoration in an accelerated but clinically representative manner.


Assuntos
Resinas Compostas/química , Resinas Compostas/metabolismo , Restauração Dentária Permanente/estatística & dados numéricos , Animais , Biofilmes , Calibragem , Bovinos , Concentração de Íons de Hidrogênio , Ácido Láctico/química , Teste de Materiais/métodos , Modelos Biológicos , Modelos Químicos , Streptococcus mutans/metabolismo , Streptococcus mutans/fisiologia , Desmineralização do Dente/induzido quimicamente
14.
Materials (Basel) ; 12(4)2019 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-30781537

RESUMO

Human periapical cyst mesenchymal stem cells (hPCy-MSCs) are a newly discovered cell population innovatively collected from inflammatory periapical cysts. The use of this biological waste guarantees a source of stem cells without any impact on the surrounding healthy tissues, presenting a valuable potential in tissue engineering and regenerative medicine applications. In the present study, hPCy-MSCs were collected, isolated, and seeded on three experimental mineral-doped porous scaffolds produced by the thermally-induced phase-separation (TIPS) technique. Mineral-doped scaffolds, composed of polylactic acid (PLA), dicalcium phosphate dihydrate (DCPD), and/or hydraulic calcium silicate (CaSi), were produced by TIPS (PLA-10CaSi, PLA-5CaSi-5DCPD, PLA-10CaSi-10DCPD). Micro-CT analysis evaluated scaffolds micromorphology. Collected hPCy-MSCs, characterized by cytofluorimetry, were seeded on the scaffolds and tested for cell proliferation, cells viability, and gene expression for osteogenic and odontogenic differentiation (DMP-1, OSC, RUNX-2, HPRT). Micro-CT revealed an interconnected highly porous structure for all the scaffolds, similar total porosity with 99% open pores. Pore wall thickness increased with the percentage of CaSi and DCPD. Cells seeded on mineral-doped scaffolds showed a superior proliferation compared to pure PLA scaffolds (control), particularly on PLA-10CaSi-10DCPD at day 12. A higher number of non-viable (red stained) cells was observable on PLA scaffolds at days 14 and 21. DMP-1 expression increased in hPCy-MSCs cultured on all mineral-doped scaffolds, in particular on PLA-5CaSi-5DCPD and PLA-10CaSi-10DCPD. In conclusion, the innovative combination of experimental scaffolds colonized with autologous stem cells from periapical cyst represent a promising strategy for regenerative healing of periapical and alveolar bone.

15.
Mol Genet Genomic Med ; 5(6): 730-741, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29178643

RESUMO

BACKGROUND: Oligodontia is a severe form of tooth agenesis characterized by the absence of six or more permanent teeth. Oligodontia has complex etiology and variations in numerous genes have been suggested as causal for the condition. METHODS: We applied whole-exome sequencing (WES) to identify the cause of oligodontia in a 9-year-old girl missing 11 permanent teeth. Protein modeling and functional analysis in zebrafish were also performed to understand the impact of identified variants on the phenotype. RESULTS: We identified a novel compound heterozygous missense mutation in WNT10A (c.637G>A:p.Gly213Ser and c.1070C>T:p.Thr357Ile) as the likely cause of autosomal recessive oligodontia in the child. Affected residues are located in conserved regions and variants are predicted to be highly deleterious for potentially destabilizing the protein fold and inhibiting normal protein function. Functional studies in zebrafish embryos showed that wnt10a is expressed in the craniofacies at critical time points for tooth development, and that perturbations of wnt10a expression impaired normal tooth development and arrested tooth development at 5 days postfertilization (dpf). Furthermore, mRNA expression levels of additional tooth development genes were directly correlated with wnt10a expression; expression of msx1, dlx2b, eda, and axin2 was decreased upon wnt10a knockdown, and increased upon wnt10a overexpression. CONCLUSIONS: Our results reveal a novel compound heterozygous variant in WNT10A as pathogenic for oligodontia, and demonstrate that perturbations of wnt10a expression in zebrafish may directly and/or indirectly affect tooth development recapitulating the agenesis phenotype observed in humans.


Assuntos
Anodontia/genética , Dente/crescimento & desenvolvimento , Proteínas Wnt/genética , Proteínas de Peixe-Zebra/genética , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados/genética , Anodontia/diagnóstico , Sequência de Bases , Criança , Dentição Permanente , Embrião não Mamífero/metabolismo , Feminino , Heterozigoto , Humanos , Modelos Animais , Morfolinos/genética , Morfolinos/metabolismo , Fenótipo , Estrutura Terciária de Proteína , Dente/patologia , Sequenciamento do Exoma , Proteínas Wnt/química , Proteínas Wnt/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/metabolismo
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