What is Periodontal Disease ?


Does blood bleed when you bite an apple ?
You would remember T.V. advertisement of toothpaste.
It was televised for the first time approximately 50 years ago (1964).
It is said that this advertisement gave an opportunity to let many people know that the disease of the tooth is not only cavity.
By the way, we think whether the one looking at a homepage already has enough judgment about periodontal disease now.
Briefly periodontal disease is an infectious disease and is a chronic disease and is a life origin-related disease.

This page introduces the basic knowledge of periodontal disease.

Perio : learning through comics 1990



We would like to introduce the booklet of periodontal disease with full illustrations.
We are surprised why Mr. Katayama made such a booklet.
As for the main point, the booklet is about "Evaluate perio by yourself",
It uses illustrations abundantly and feature a story of a certain family.

All about periodontal disease


Biofilm (also called plaque, dental plaque) is formed when sucrose is broken down by an enzyme called glucosyltransferase (GTF) which Streptococcus mutans secretes and make insoluble glucan.

Figure bellow The bacteria exchange information using QS signal becomes the biofilm group and builds the territory in each part and lives.


Plural bacteria make biofilm which are slimy while taking the communication using QS signal after floating bacteria attaching, and having formed a microcolony.

When biofilm is formed, various other bacteria are attached, colonized and repeat an increase and the collapse.
And it produces acid during 24-48 hours and begin to dissolve tooth.
This leads to actual outbreak of cavity.
In addition, the accumulated biofilm acts as the barrier protecting bacteria against oxygen, antibiotics, the self-purification of saliva.
Therefore the tooth under coated biofilm becomes the environment with little air, and it creates an environment where anaerobes spread a lot..
Periodontal disease is a disease to have anaerobes to get into along the tooth root from the periodontal pocket which is the border of a tooth and the gum.

When bacterial breeding becomes enormous, bacteria invade the pocket deeply, and the bone melts steadily accordingly.
As subjective symptoms hardly come out at the early inflammatory stage, it progresses while the person cannot not notice it. We call such a disease Silent Disease.

Sometimes bleeding be observed in the mouth well when you brush your teeth, and you might find red parts in the gums.
It is important not to overlook such a slight change ; is pointed.

It might bleed when it progresses a little more when you brush your teeth. Then a person feel that a tooth loosened and the person feeling gums itchy.
Furthermore, mobility of teeth gets larger when it progresses and repeats swelling, and the drainage of the gums occur.
It becomes difficult to chew it in this stage.
A risk to lose a tooth by leaving unattended rises steadily.

 Key words 
Biofilm/Cavity/Periodontal disease/Silent disease/Bleeding/Inflammation/Loosening of tooth/
画像の説明,Silent Disease
Silent Disease

1. Kolenblander PE. Oral microbial communities:biofilms,interactions,and genitic systems. Annu Rev Microbiol, 54:413, 2000.
2. Katsuji Okuda, Dental biofilm, Ishiyaku shuppan,2010.                              
3. Katsuji Okuda, Battle with the assassination group den Tal biofilm conferring on the bidding, Japan Dental Association magazine, 64:19, 2011.               

Existing bacteria in the plaque

Characteristic image of periodontal disease

TreponemaTreponema denticolaSpirillum

In additionMicrococcus Short bacillus
Entamoeba gingivalisEntamoeba gingivalisProtozoan
move while changing the form slowly
Candida albicansCandida albicansProtozoan
False spawn
白血球White blood cellhave a nucleus divided into some and granules

A phase contrast microscope

Relations between periodontal disease and various disease of the body

Periodontal disease has deep relation with various diseases of whole body, and in late years it began to attract more attention.
( Periodontal disease appears in Guinness as infectious disease with much number of the infected people ! )

Dental focal infection

The dental focal infection, implies an infectious disease of tooth and periodontium and said that a person has a disease secondarily to different organs.
Besides tooth and periodontium, tonsil and rhinopharynx are considered as the source of infection, too.


Various diseases of the whole body

・Arteriosclerosis, heart problem, cerebral infarctionAs for the arteriosclerosis, lifestyles such as the inappropriate eating habits and lack of exercise, stress were considered to be a factor, but the bacterial infection such as periodontal disease pathogens has been performed a close-up of as a different factor. A material inducing arteriosclerosis by the stimulation such as periodontal disease pathogens appears, and there is plaque in blood vessel, and the way of the blood narrows. When plaque comes off, and a lump of the blood is made, blood vessel is clogged up on the spot and is clogged up in the narrow place of the blood vessel.
Angina, myocardial infarction
The blood vessel which sends blood to the myocardium by arteriosclerosis becomes narrow and is the disease that is occupied, and blood supply disappears to myocardium, and may result in death.
Cerebral infarction
The plaque of the blood vessel of the brain is clogged up and is a disease that a lump and plaque of the blood fly from a carotid and heart and are clogged up with a cerebral blood vessel. It is said that the person with periodontal disease is easy to suffer from the 2.8 times cerebral infarction of the person who is not so.

In this way, it is revealed that inflammation of a tooth and the periodontium has many influences on a whole body in the recent studies.

In association with the diseases of the whole body, must be investigated further.
You should review the lifestyle including everyday toothbrushing and eating habits which are connected in preventing various diseases of the whole body.

Good oral management leads to the prevention of disease of entire body.

The cause of the death of 26th United States President Theodole Roosevelt died in 1919 was "pulmonary embolism ", and it is said that its cause was a cavity of the tooth.
As he was busy, he did not treat the cavity, and the pus of the root apex flowed in to the blood vessel causing pulmonary embolism.

This is a poster of cavity prevention day of Saitama dental association, and "dental focal infection" was the theme in 1932
A precious poster of the focal infection. 1932

Let's check periodontal disease bacteria chain in oral cavity !


page back