Chula Researches “Tooth Loss” in Thai People- A Hereditary Condition Caused by Genetic Abnormalities

Chulalongkorn dental research reveals that Thais suffer more tooth loss than their foreign counterparts with 9 out of 100 Thais suffering the condition.  One of the most important factors is hereditary gene abnormalities.

“Cavities, gingivitis, oral ulcers” are familiar oral disorders that are regularly treated by dentists.  On the other hand, “tooth loss” is lesser known but found in many Thais.  World and Asian statistics show an average of 6% of the population, while past research by Phitsanulok and Khon Kaen Universities reported 26% and 13% of Thais with tooth loss conditions respectively.                                                   

Is tooth loss in Thais caused by genetic abnormalities? and from which genes? This was a research challenge for Dr. Charinya Kanchanasevee, a graduate of the Master’s Degree Program in Dentistry, Chulalongkorn University, who studied the “Prevalence and Characteristics of Tooth Loss in Thai Patients and Genetic Changes Associated with Tooth Loss in Thai Families” — the research which received an Outstanding Award for Master’s Degree Students Research in Health Sciences 2021 from Chula.

“Tooth loss” and its effects on health

Tooth loss refers to the absence of teeth from birth because the tooth bud cannot be found.  The tooth bud is the tissue in the jaw bone that can be seen by dentists in X-rays only.

“Having one missing tooth is already considered a tooth loss condition. In the past, most Thai studies have found missing teeth in the area of the second lower molar, leaving no molars to chew food. Also, tooth loss correlates with abnormalities in the oral cavity, such as smaller than normal front teeth,” Dr. Charinya explained.

Tooth loss can be caused by many factors, including genetics and environmental conditions, such as when the pregnant mother has an infection, doesn’t eat all 5 groups of food, or takes medications that affect the formation of her child’s teeth, etc.

“A normal person has 20 primary teeth, and 32 permanent teeth.  Tooth loss occurs mainly in permanent teeth, causing patients to have a problem chewing food, and abnormal facial structures. It affects the person’s state of mind and lifestyle. The research found patients with up to 12 permanent teeth loss,” Dr. Charinya said.

Tooth loss research process

This dental research took three years (2018 – 2021), divided into research on the prevalence of tooth loss by studying x-ray film of patients who were treated at the Faculty of Dentistry Hospital, Chulalongkorn University totaling 1,090 samples.                             

The genetic research studied 5 families selected at random totaling 9 samples to learn about the correlation between genes and family members.

“We decoded the genes using technological advances in DNA nucleotide sequencing, aka next generation sequencing.  It took about 1-2 months. Once the results were obtained, they were processed and analyzed for genetic abnormalities at the Excellence Center for Genomics and Precision Medicine, then compared against Thai and foreign databases.”

The gene causing tooth loss found in Thai people

Research results show the prevalence of tooth loss in Thais is at 9 percent which is lower than previous studies done in Thailand, but higher than that of the world and Asia.

“Genetically, the findings showed people with tooth loss in all five families with the same gene mutation in the WNT5A gene.  This is the gene involved in the tooth formation process and one of several genes whose mutation have previously been reported in people with tooth loss,” Dr. Charinya said.

The results of this research are new knowledge showing that WNT10A gene abnormality at this location is more common in Thai and Asian people compared to other ethnicities. Moreover, abnormality at the new location was also found, thereby expanding genetic knowledge in people with tooth loss.

Although it is a genetically induced condition, there are treatment approaches such as different types of dentures, dental implants, etc., to provide the patient with the closest possible quality of life to normal.

“People with missing teeth or children whose teeth have fallen out but no permanent teeth grown in their place should consult the dentist as soon as possible to have a dental scan and plan timely treatment,” Dr. Charinya suggested.

People with tooth loss or oral disorders can make an appointment for dental treatment at The Dental Hospital Faculty of Dentistry, Chulalongkorn University, 1st floor, Somdet Ya 93 Building, Chula Faculty of Dentistry, Tel. +66-2218-8705 and receive a consultation at the Excellence Center for Genomics and Precision Medicine, Department of Physiology, 4th Floor, Building 14, Faculty of Dentistry, Tel. +66-2218-8695.

Website: https://www.research.chula.ac.th/th/organization/4282/,
or http://www.dent.chula.ac.th/hospital/service.php