Osteogenesis imperfecta with ectopic mineralizations in dentin and cementum and a COL1A2 mutation

Abstract

We report a Thai father (patient 1) and his daughter (patient 2) affected with osteogenesis imperfecta type IV and dentinogenesis imperfecta. Both were heterozygous for the c.1451G>A (p.Gly484Glu) mutation in COL1A2. The father, a Thai boxer, had very mild osteogenesis imperfecta with no history of low-trauma bone fractures. Scanning electron micrography of the primary teeth with DI of the patient 2, and the primary teeth with DI of another OI patient with OI showed newly recognized dental manifestations of teeth with DI. Normal dentin and cementum might have small areas of ectopic mineralizations. Teeth affected with DI have well-organized ectopic mineralizations in dentin and cementum. The "French-fries-appearance" of the crystals at the cemento-dentinal junction and abnormal cementum have never been reported to be associated with dentinogenesis imperfecta, either isolated or osteogenesis imperfecta-associated. Our study shows for the first time that abnormal collagen fibers can lead to ectopic mineralization in dentin and cementum and abnormal cementum can be a part of osteogenesis imperfecta.

Dental and craniofacial defects in the Crtap−/− mouse model of osteogenesis imperfecta type VII

“…The description of periodontal phenotypes associated with OI is exceedingly rare, which is surprising considering that cementum, PDL, and alveolar bone extracellular matrices are approximately 90% type I collagen and would be expected to manifest direct effects of OIassociated mutations. A single report of type IV OI due to mutations in COL1A2 describes by scanning electron microscopy, "bush-like" ectopic calcifications on cementum surfaces of primary teeth of the affected child, the first such observation (Kantaputra et al, 2018).…”

Isolated dentinogenesis imperfecta with glass‐like enamel caused by COL1A2 mutation

“…DSPP encodes for a single mRNA giving three proteins including DSP (dentin sialoprotein), dentin glycoprotein (DGP), and dentin phosphoprotein (DPP). Dentinogenesis imperfecta can be associated with a number of genetic disorders especially OI, a group of brittle bone disorders caused mainly by mutations in COL1A1, and COL1A2 (Kantaputra, 2001;Kantaputra et al, 2018). It is noteworthy that the clinical and radiographic features of DGI caused by mutations in DSPP, COL1A1, and COL1A2 are not distinguishable.…”

ADAMTSL1 and mandibular prognathism

“…All five patients were called for clinical and radiographic examination and found to have mandibular prognathism. Two members of Family 2 (II‐2 and III‐2) carried a heterozygous mutation in COL1A2 (c.1451G>A; p.Gly484Glu) and have been reported to have osteogenesis imperfecta with dentinogenesis imperfecta . Patients I‐1 and II‐1, who had mandibular prognathism and the ADAMTSL1 variant, did not have osteogenesis imperfecta, dentinogenesis imperfecta, or a COL1A2 mutation (Figure ; Table ).…”