Măseaua este sensibilă.

Măseaua means the molar or the back tooth. It is more specific than dinte, which means tooth in general.

So:

• dinte = tooth
• măsea = molar

In this sentence, Romanian is specifically talking about a molar, not just any tooth.

The ending -ua here shows the definite article, so măseaua means the molar.

Romanian usually puts the definite article at the end of the noun, unlike English, which uses a separate word like the.

Compare:

• măsea = a molar
• măseaua = the molar

This is a very common Romanian pattern.

Este means is. It is the 3rd person singular form of the verb a fi = to be.

So the structure is:

• Măseaua = the molar
• este = is
• sensibilă = sensitive

Romanian normally uses a fi in sentences like this, just as English uses to be.

Yes. E is a very common short form of este.

So both are correct:

• Măseaua este sensibilă.
• Măseaua e sensibilă.

The version with este may sound a little more full or careful, while e is extremely common in everyday speech.

Because măsea is a feminine noun, the adjective has to agree with it.

Romanian adjectives usually change form to match the noun’s gender and number.

Here:

• măsea = feminine singular
• sensibilă = feminine singular form of sensitive

Compare:

• dinte sensibil = sensitive tooth
  (dinte is masculine)
• măsea sensibilă = sensitive molar
  (măsea is feminine)

In this sentence, no. Here sensibilă means physically sensitive, especially in the sense of reacting painfully to cold, heat, sweets, pressure, and so on.

Because the subject is a tooth, the medical/physical meaning is the natural one.

A rough pronunciation guide is:

muh-SEH-wa ES-te sem-see-BEE-luh

A few useful details:

• ă is a short central vowel, something like the a in sofa
• ea in măseaua is pronounced together like e-a, forming sea
• ă at the end of sensibilă is again that short central sound

The stress is roughly:

• măSEAua
• ESte
• sensiBIlă

In Romanian, adjectives often come after the noun, especially in ordinary descriptive statements.

So:

• măsea sensibilă = sensitive molar

That is more normal than putting the adjective first.

You may sometimes see adjectives before nouns, but that often gives a more literary, emphatic, or stylistic effect. For a simple medical statement, măseaua este sensibilă is the natural order.

Yes, but the meaning becomes less specific.

• Dintele este sensibil. = The tooth is sensitive.
• Măseaua este sensibilă. = The molar is sensitive.

So if you know it is specifically a molar, măsea is the better word.

Notice again the adjective agreement:

• dintele → masculine → sensibil
• măseaua → feminine → sensibilă

If you want to say A molar is sensitive or One molar is sensitive, you would usually say:

O măsea este sensibilă.

Here:

• o măsea = a molar
• măseaua = the molar

So the difference is:

• O măsea este sensibilă. = A molar is sensitive.
• Măseaua este sensibilă. = The molar is sensitive.

The plural would be:

Măselele sunt sensibile.

Breakdown:

• măsea = molar
• măseaua = the molar
• măsele = molars
• măselele = the molars

And:

• este = is
• sunt = are
• sensibilă = feminine singular
• sensibile = plural

So Romanian changes both the noun and the adjective in the plural.

Yes, this is perfectly natural Romanian, especially in a dental or everyday health context.

You might also hear closely related phrases such as:

• Măseaua mă doare. = My molar hurts.
• Am o măsea sensibilă. = I have a sensitive molar.
• Măseaua e sensibilă la rece. = The molar is sensitive to cold.

So your sentence is correct and idiomatic.