koko ha sika desu.

When は is used as the topic particle, it is pronounced wa, not ha.

So in ここは歯科です, you read it as:

ここは しか です
koko wa shika desu

But when は is part of a normal word, it is usually pronounced ha.

Examples:

• はな = flower / nose, depending on kanji, pronounced hana
• ここは = here + topic particle, pronounced koko wa

This is one of the first pronunciation exceptions learners meet in Japanese.

ここ means here, a place near the speaker.

It belongs to the ko-so-a-do set:

• ここ = here
• そこ = there, near the listener
• あそこ = over there, away from both
• どこ = where

So ここは sets this place / here as the topic of the sentence.

は marks the topic of the sentence.

In ここは歯科です, the topic is ここ = here.
The rest of the sentence says something about that topic:

• ここは = as for this place / here
• 歯科です = it is dentistry / a dental department / a dental clinic, depending on context

A very natural way to understand the structure is:

As for this place, it is the dental department.

This is why Japanese sentences often do not match English word-for-word.

歯科 literally means dentistry or dental department.

Depending on context, it can refer to:

• a dental department in a hospital
• a dental clinic
• the field of dentistry

In a sentence like ここは歯科です, it often means something like:

• This is the dental department
• This is the dentist’s office
• This is the dental clinic

The exact English wording depends on where the sentence appears.

歯科 is pronounced しか (shika).

Breakdown:

• 歯 = shi
• 科 = ka

Be careful not to confuse it with other words pronounced shika, such as:

• 鹿 = deer
• しか as a grammar word meaning only in some patterns

The kanji and context make the meaning clear.

Japanese often leaves out subjects and objects when they are obvious from context.

In English, you might expect something like:

• This is a dental clinic
• It is the dental department

But Japanese often does not need this or it explicitly.
Instead, it simply makes here the topic:

ここは歯科です
As for here, it is the dental department.

This kind of omission is very normal in Japanese.

です is the polite copula. In beginner explanations, it is often translated as is / am / are, though it does not work exactly the same way as English to be.

Here it gives a polite, neutral statement:

• 歯科です = It is dental / the dental department
• ここは歯科です = Here is the dental department or This is the dental clinic

It makes the sentence polite and appropriate for everyday conversation.

Not very naturally.

A literal breakdown is something like:

• ここ = here
• は = topic marker
• 歯科 = dentistry / dental department
• です = is

So the structure is close to As for here, it is dentistry.

But natural English translations would usually be:

• This is the dental department
• This is the dental clinic
• Here is the dentist’s office

It is better to understand the grammar than to force a word-for-word English sentence.

Yes, it can be natural, especially in a context like:

• pointing out a department in a hospital
• showing someone a clinic
• identifying a room or area on a map or sign

However, in some situations, Japanese speakers might say slightly different things depending on nuance:

• ここは歯医者です is less natural if you mean this place is a dentist’s office, because 歯医者 usually refers to the dentist or dentist’s office in a more casual way
• こちらは歯科です sounds more polite than ここは歯科です
• On a sign, you might simply see 歯科 with no full sentence

So ここは歯科です is correct and understandable, but real-life phrasing depends on context.

This is a very common question.

歯科

• more formal
• often means dentistry or dental department
• common in hospitals, clinic names, and official language

歯医者

• more casual
• can mean dentist
• can also mean dentist’s office in everyday speech

Examples:

• 歯科に行きます = I’m going to the dental department / dental clinic
• 歯医者に行きます = I’m going to the dentist

In your sentence, 歯科 sounds a bit more formal or institutional.

Normally, Japanese is written without spaces:

ここは歯科です。

The spaced version is usually just for learners, to make the parts easier to see:

• ここ
• は
• 歯科
• です

So the spaces are a teaching aid, not standard Japanese writing.

Yes, but the nuance changes.

• ここは歯科です = As for here, it is the dental department
• ここが歯科です = This is the dental department / Here is the dental department

Using が can sound more identifying or contrastive, especially when you are pointing out the correct place among several possibilities.

For example:

• someone asks Which room is dental?
• you answer ここが歯科です = This is the dental department

So both are possible, but は presents the place as the topic, while が can sound more like identifying or highlighting it.