Imaging biomarkers as surrogate endpoints for clinical trials on permanent tooth regeneration in congenital tooth
Akiko Murashima-Suginami1, Takayoshi Ishimori2, Takeshi Sawada2
1Dentistry & Oral Surgery, Medical Research Institute KITANO HOSPITAL, PIIF Tazuke-kofukai, Osaka, Japan; Toregem BioPharma, Co., Ltd, Kyoto, Japan.
Objectives:
Multiple genes are responsible for the absence of teeth at birth, known as congenital tooth agenesis. The humanized anti-USAG-1 antibody, TRG035, was developed for use in molecular-targeted therapy for the regeneration of congenitally absent teeth in patients with congenital tooth agenesis. Detecting congenital tooth agenesis in children aged 2-5 years using X-ray examination alone is challenging. Therefore, developing imaging biomarkers that identify early tooth buds and ridges during the bud and early cap stages is essential. In this study, the aim was to develop imaging biomarkers by combining MRI and CT/X-rays to identify each developmental stage from the dental lamina to the tooth germ.
Methods:
Ferret pups aged 0-25 days were photographed and micro-CT was performed.
Results:
An imaging biomarker using MRI and CT/X-rays were developed that could visualize the dental lamina and pre-calcified tooth germ, both of which were previously difficult to accurately identify.
Conclusions:
This system is expected to enable the accurate diagnosis of congenital tooth agenesis and contribute to the clinical development of treatments for this condition.

