In the third national dental survey of hypophosphatasia in Japan, researchers analysed the dental issues faced by Japanese patients, publishing their findings in Scientific Reports.
Hypophosphatasia is a relatively common skeletal disease that primarily affects bone and tooth strength.
People with hypophosphatasia have variants in the gene responsible for making tissue-nonspecific alkaline phosphatase, which is important for bone mineralisation. Although this generally leads to weakened bones, issues with teeth are also common. Less severe forms of hypophosphatasia are often diagnosed when the first teeth fall out earlier than expected, before four years of age. Dentists are therefore a major care provider for children with this disease—but they aren’t always familiar with its symptoms.
To explore the dental issues in patients with hypophosphatasia, researchers from Osaka University have conducted nationwide surveys of dental clinics every five years since 2013.
In the most recent survey, they collected data from 103 cases from 30 clinics. This represents a big jump in numbers from the last two surveys (with 19 and 52 cases), allowing the researchers to conduct an in-depth analysis of the dental issues faced by Japanese patients.
Specifically, the patients with odonto-type hypophosphatasia (i.e. with symptoms involving the teeth only) were more likely to lose their first teeth early, whereas those with non-odonto-type disease were more likely to have tooth misalignment and tooth hypomineralisation (where the enamel on the outside of the teeth softens). Non-odonto-type disease was also linked to poor oral habits, such as finger sucking and tongue thrusting, and problems with swallowing.
“The trends that we observed in this study will be helpful for dentists who might come across patients with hypophosphatasia in their clinics,” senior author Dr Kazuhiko Nakano said.
