Eu penso há muito tempo que deveríamos considerar os dentes como órgãos sensoriais, antes de tudo...
Progenitors of the protochordate ocellus as an evolutionary origin of the neural crest
EvoDevo. 2013; 4: 12.
Published online 2013 April 10. doi: 10.1186/2041-9139-4-12
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Moreover, to support the idea that mesenchymal fates could be elaborated de novo in the neural crest, we point out that dentin is a true unique neural crest innovation [14]. Besides, teeth-like odontode structures (conodont elements) represent the first hard mineralized tissue found in the bodies of extinct jawless chordate conodonts [56-58]. There are views inferring that odontoblasts represent an evolutionary modification of the neuroglial fate, being former electroreceptors or sensory cells monitoring temperature and chemical changes. These receptors were shielded by a collagenous and proteinaceous matrix that was later mineralized [51,59-61] (extensively discussed in [21,26]). This hypothesis is supported by the fact that odontoblasts express mechano- and thermosensitive transient receptor potential ion channels (TRPV1, TRPV2, TRPV3, TRPV4, TRPM3, KCa, TREK-1) and voltage-gated sodium channels, contact pain fibers and generally facilitate pain sensation in the tooth [62,63].
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3626940/
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