Dental Challenges in Hypophosphatasia Patients: Key Insights

• Hypophosphatasia impacts both bone and dental health, with early tooth loss being a key symptom.
• A nationwide survey in Japan highlights differences in oral manifestations between odonto-type and non-odonto-type hypophosphatasia.
• Early diagnosis is critical for preventing long-term dental issues, especially with available enzyme replacement therapy.

New Insights Into Dental Problems in Hypophosphatasia Patients

JAPAN: Hypophosphatasia, a condition that primarily affects bone and dental strength, has been the focus of a recent nationwide dental survey conducted by researchers at Osaka University. Published in Scientific Reports, this study provides detailed insights into the oral health challenges faced by Japanese patients with hypophosphatasia. The findings aim to enhance diagnostic accuracy and improve treatment outcomes for individuals affected by this complex disease.

Understanding Hypophosphatasia and Its Impact on Oral Health

Hypophosphatasia arises from genetic variants that impair tissue-nonspecific alkaline phosphatase production, a key enzyme involved in bone mineralization. While weakened bones are a hallmark of the disease, dental complications are also prevalent. In less severe cases, the condition is often first identified when primary teeth fall out prematurely—typically before the age of four. This makes dentists pivotal in diagnosing and managing the condition, though awareness of its symptoms remains limited among dental professionals.

The research team, led by Osaka University, has been conducting nationwide surveys every five years since 2013 to better understand the dental implications of hypophosphatasia. Their most recent effort collected data from 103 cases across 30 clinics, marking a significant increase from previous surveys, which included only 19 and 52 cases. This larger dataset enabled a more comprehensive analysis of the disease’s oral manifestations.

Distinct Oral Manifestations Between Disease Types

One of the study’s notable findings was the differentiation between two patient groups based on their symptoms. “We had enough cases that we could break them down into two groups—those whose symptoms involved the teeth only, known as odonto-type disease, and those who had other symptoms, which we termed non-odonto-type disease,” explained Rena Okawa, the study’s lead author.

Patients with odonto-type hypophosphatasia were more likely to experience premature loss of primary teeth. In contrast, those with non-odonto-type disease exhibited higher rates of tooth misalignment and hypomineralization, where the enamel becomes softer and more prone to damage. Non-odonto-type patients also demonstrated poor oral habits, such as finger sucking and tongue thrusting, alongside difficulties with swallowing.

Implications for Diagnosis and Treatment

The study underscores the importance of recognizing these varied oral manifestations to improve diagnostic accuracy. “The trends that we observed in this study will be helpful for dentists who might come across patients with hypophosphatasia in their clinics. Improved knowledge of the various ways this disease presents will lead to better diagnostic rates and earlier treatments for affected patients,” stated Kazuhiko Nakano, the study’s senior author.

Early diagnosis is particularly crucial given the availability of enzyme replacement therapy, which can mitigate complications affecting adult teeth later in life. By identifying suspected cases early, dentists can collaborate with medical professionals to provide multidisciplinary care tailored to the needs of hypophosphatasia patients.

A Step Forward in Addressing an Underdiagnosed Condition

The findings from Osaka University’s nationwide survey offer valuable insights into the dental challenges faced by individuals with hypophosphatasia. By highlighting distinct oral symptoms associated with different forms of the disease, the study equips dental practitioners with the knowledge needed to identify and manage this condition more effectively. As awareness grows, the hope is that improved diagnostic practices will lead to timely interventions, ultimately enhancing the quality of life for patients.

The study, titled “Japanese nationwide dental survey of hypophosphatasia reveals novel oral manifestations,” was published in Scientific Reports (doi.org/10.1038/s41598-025-91043-7).