Inquired about this directly with Thai Embassy in Mexico. Here is their reply: The DTV visa may not be suitable for your visit to Thailand. Applying for an inappropriate visa type could result in a change of visa type without prior notice or a rejection of your application.
Considering that a dental appointment differs from "medical treatment," we recommend applying for a Tourist Visa TR5 Medical Treatment (valid for up to 60 days). You may also request a visa extension through the Thai Immigration Bureau. For more information, you can visit the E-extension platform at
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