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Where are the Dentists in Japan?

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In a Japanese city, one can often expect a convenience store within walking distance.

They sell food, drinks, and other necessities. They allow people to pick up their packages at the stores as well as pay for online purchases. Many consider these stores as infrastructure, and there will probably be some demand no matter where you open a new store.

To see how common they can be, we can look at the following map of this area around the Ginza station in Tokyo:

Map of Ginza station area with convenience stores boxed

Yahoo!地図

The boxes show that there are 25 convenience stores in this area.

However, this following map of the same area shows that there are 28 of a different type of business:

Map of same Ginza station area with dental clinics boxed

Yahoo!地図

These are all dental clinics. Nationwide, there are more dental clinics than convenience stores1:

Hair salons are more common than real estate companies, followed by clinics, dental clinics, and convenience stores

Of course, this isn’t going to be true everywhere in Japan. If we expand the map, or move it around, we could easily find areas with more convenience stores than dentists. However, the fact that there are areas with more dental clinics than convenience stores in the middle of Tokyo might be surprising if you know how ubiquitous convenience stores are in Japanese cities.

However, this may not make sense intuitively. Where are these dentists?

Comparisons by Country

The fact that there are more dental clinics than convenience stores doesn’t mean that Japan has an abnormally large dentist population.

Japan had a large number of dentists compared to other OECD countries (The United States was not in the data set)2:

Practising dentists provide services for patients. They include stomatologists, dental and maxillofacial surgeons.

Japan has the largest number of practicing dentists in the incomplete dataset of OECD countries

Source: OECD

But per capita, Japan is comparable to other countries:

Lithuania has the largest number of dentists per 1000 people in the incomplete dataset of OECD countries

Source: OECD

Japan is 2nd in terms of Professionally Active Dentists:

Professionally active dentists are practising dentists and other dentists for whom their education in dentistry / stomatology is a prerequisite for the execution of the job.

The United States has the largest number of professionally active dentists in the incomplete dataset of OECD countries

Source: OECD

But again, it’s comparable to other OECD countries per capita:

Israel has the largest number of professionally active dentists per 1000 people in the incomplete dataset of OECD countries

Source: OECD

Nevertheless, there certainly is discussion within Japan about the large number of dental clinics. The common explanation is that there is a large number of dental schools, so there are a lot of dentists, which resulted in a large number of dental clinics.

Comparisons by Prefecture

To better understand why and where there are many dental clinics, let’s take a look at the trends by prefecture. The following is a map of the general population by prefecture:

Tokyo has the largest population

Source: Portal Site of Official Statistics of Japan

Tokyo, Kanagawa, and Osaka have the largest populations

Source: Portal Site of Official Statistics of Japan

While prefectures with a larger population tend to have more convenience stores, many less populated prefectures (such as Yamanashi and Miyagi) have more convenience stores per capita3:

Map of convenience stores per capita

Bar graph of convenience stores per capita

The correlation between a prefecture’s population and the number of convenience stores per capita is weak, with a very weak correlation coefficient of 0.187:

Plot of correlation between population and dental clinics

On the other hand, prefectures with a larger population have more dental clinics per capita4:

Map of dental clinics per capita

Tokyo has the most dental clinics per capita

The correlation between a prefecture’s population and the number of dental clinics per capita is stronger at 0.695:

Plot of correlation between popuation and dental clinics

According to a consulting company for dentists who want to start a dental clinic, many dentists think that they should start their own practice in a city, because people have higher incomes and are thus able to spend more money on dental care.

However, dental clinic signs don’t stand out as much as convenience stores, so it’s probably easier to not notice them.

They also note that most dentists choose a location that is either close to their family, close to a clinic that they had previously worked in, close to where they have lived before, or close to a dental school.

The following map show the number of dental schools by prefecture:

Tokyo has the most dental schools by prefecture

Source: 歯学部 - Wikipedia

There is an even stronger correlation coefficient of 0.779 between the number of dental schools in a prefecture and the number of dental clinics per capita5:

Plot of correlation between number of dental clinics and dental clinics per capita

Therefore, we can infer that many aspiring dentists attend dental schools (which are more common in populated areas), get a job in the same area, and start their own practice in the same area for personal and financial reasons.

Dental clinics aren’t as obvious in appearance as convenience stores, so we don’t realize how common they are in cities.

This probably is not the full picture, and we cannot conclude causation from just this data, but it seems like a plausible theory for why there are more dental clinics than convenience stores without many people realizing.

Footnotes

1:

2: I originally had a map and graph of the dentists by country and dentists per capita by country here, but I learned that the WHO API was returning old data for some reason, so I replaced it with OECD Country Data.

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