Complex analysis of multiple single nucleotide polymorphisms as putative risk factors of tooth agenesis in the Hungarian population.

OBJECTIVES: The role was studied of multiple single nucleotide polymorphisms in tooth agenesis in the Hungarian population using a complex approach. METHODS: Eight SNPs, PAX9 -912 C/T, PAX9 -1031 A/G, MSX1 3755 A/G, FGFR1 T/C rs881301, IRF6 T/C rs764093, AXIN2-8150 A/G, AXIN2-8434 A/G and AXIN2-30224 C/T, were studied in 192 hypodontia and 17 oligodontia cases and in 260 healthy volunteers. Case-control analysis was performed to test both allelic and genotypic associations as well as associations at the level of haplotypes. Multivariate exploratory Bayesian network-based multi-level analysis of relevance (BN-BMLA) as well as logistic regression analysis were performed. RESULTS: Conventional statistics showed that PAX9 SNP -912 C/T and the MSX1 SNP changed the incidence of hypodontia, although after Bonferroni correction for multiple hypothesis testing, the effects were only borderline tendencies. Using a statistical analysis better suited for handling multiple hypotheses, the BN-BMLA, PAX9 SNPs clearly showed a synergistic effect. This was confirmed by other multivariate analyses and it remained significant after corrections for multiple hypothesis testing (p < 0.0025). The PAX9-1031-A-PAX9-912-T haplotype was the most relevant combination causing hypodontia. Interaction was weaker between PAX9 and MSX1, while other SNPs had no joint effect on hypodontia. CONCLUSION: This complex analysis shows the important role of PAX9 and MSX1 SNPs and of their interactions in tooth agenesis, while IRF6, FGFR1 and AXIN2 SNPs had no detectable role in the Hungarian population. These results also reveal that risk factors in hypodontia need to be identified in various populations, since there is considerable variability among them.

[Treatment options of missing teeth resulting from hypodontia. Literature overview I]. / A hypodontia következtében létrejött foghiány ellátásának lehetôségei. Irodalmi áttekintés I.

Nowadays there is an increased need to identify genetic polimorphisms, the underlying genetic factors of hypodontia. This article aims to describe the genetic components of hypodontia, the most frequent congenital tooth development disorder, as well as its interdisciplinary treatment. Congenitally missing teeth may cause serious emotional and physical problems particularly during adolescence. To prevent this, the early diagnosis and the development of definitive treatment plan are vital. In this work the interdisciplinary management involving a dental team plays a crucial role. The most important first step in hypodontia management is to decide whether to apply space closure or space opening when making room for fixed restorations and implants.

[Treatment options of missing teeth resulting from hypodontia. Literature overview II]. / A hypodontia következtében létrejött foghiány ellátásának lehetoségei. Lrodalmi attekintés II.

Congenital hypodontia may cause serious emotional and physical problems which can become particularly grave during adolescence. This article highlights the importance of early diagnosis and the prevention of the progress of the state, and discusses a variety of definitive treatment plans. The aim of restorative dentistry is to restore function, improve appearance and prevent complications caused by hypodontia. When developing a treatment plan, first the severity of hypodontia, the number of missing teeth, and some other factors have to be considered. This can be followed by the treatment, which involves an interdisciplinary dental team.

[Isolating, culturing and characterizing stem cells of human dental pulp origin]. / Humán fogbél eredetu ossejtek izolálása, tenyésztése es jellemzése.

Evidence has been accumulating for the presence of stem cells in dental tissues. The authors' studies aimed to produce primary culture from human dental pulp. Furthermore, they wanted to identify clonogenic cells with progenitor properties in these cultures, and to characterize their proliferative capacity. The dental pulp was isolated from surgically removed wisdom teeth. The extracellular matrix was enzymatically degraded to obtain isolated cells for culturing. Identification of STRO-1 mesenchymal stem cell marker was achieved by immunocytochemistry. Osteogenic differentiation was detected by the application of Alizarin Red. The proliferative activity of the cell cultures in response to serum, EGF and BMP2 was estimated by MTT assay. The authors' most important finding is the successful establishment of stable primary cell culture from human dental pulp tissue. The cultures can be passaged multiple times and they contain clonogenic, STRO-1 immunopositive cells. Their mineralization capacity was shown by mineralized deposits as a result of induction by suitable medium. The presence of serum increased, while both EGF and BMP2 concentration-dependently decreased the cell proliferation in the cultures. The authors' model provides the foundation for studies of the proliferation and differentiation of dental pulp cells at molecular level, and opens a new direction towards the biological regeneration of dental tissues.