Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jun 4;25(1):906.
doi: 10.1186/s12903-025-06315-5.

Dentinogenesis imperfecta type II dentin: nanostructural mechanics analysis

Gao Jia #  1   2 , Jiang Tianle #  1   2 , Jiang Haofu #  1   2 , Chen Wenxia  1   2 , Tu Junhao  1   2 , Yi Mengjia  1   2 , Mao Yixin  1   2 , Chen Yang  1   2 , Wang Xia  3 , Chen Shuomin  4   5 , Huang Shengbin  6   7
Affiliations

Dentinogenesis imperfecta type II dentin: nanostructural mechanics analysis

Gao Jia et al. BMC Oral Health. .

Abstract

Objectives: This study investigated the nanomechanical properties, microstructure, and composition of dentinogenesis imperfecta type II (DGI-II) peritubular dentin (PTD) and intertubular dentin (ITD) and examined the correlations between them.

Materials and methods: Six samples from each of the normal and DGI-II groups were prepared by cutting the midcoronal dentin perpendicular to the dentin tubules. The number and morphology of the dentin tubules were then observed by scanning electron microscopy (SEM). Hydroxyapatite (HAP) was detected using high-resolution atomic force microscopy (HR-AFM). The chemical composition was determined using atomic force microscopy-infrared spectroscopy (AFM-IR). The nanomechanical properties were evaluated using amplitude modulation-frequency modulation (AM-FM) techniques. Finally, a multiple linear regression (MLR) model was used to verify the correlations between PTD and ITD.

Results: SEM of the DGI-II dentin revealed a considerable reduction in the number and area of the tubules. HR-AFM revealed dramatic increases in the HAP particle size and DGI-II dentin nanoscale roughness, especially PTDs. AFM-IR revealed that in the DGI-II groups, the phosphate content decreased in both the PTDs and ITDs, whereas the amide I (A-I) and amide II (A-II) content was elevated in the ITDs. AM-FM testing revealed a considerable reduction in the Young's modulus and increases in the PTD and ITD indentations in the DGI-II dentin. MLR demonstrated that the changes in microstructure and composition were related to a decrease in the nanomechanical properties of the DGI-II dentin.

Conclusions: The DGI-II dentin nanomechanical properties deteriorated considerably, especially those of the PTDs, presumably because of alterations in the HAP and chemical composition.

Clinical relevance: Understanding the nanomechanical properties, microstructure, and composition of DGI-II dentin could help dentists develop novel individualized restorative techniques.

Keywords: Chemical composition; Dentinogenesis imperfecta; Intertubular dentin; Microstructure; Nanomechanical properties; Peritubular dentin.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: This study was conducted with the approval of the Wenzhou Medical University Ethics Committee (WYKQ2023006). Written informed consents were obtained from all the study participants. All experiments were performed in accordance with relevant guidelines and regulations. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
SEM images of normal and DGI-II coronal dentin
Fig. 2
Fig. 2
HR-AFM images of the PTD and ITD in normal and DGI-II coronal dentin
Fig. 3
Fig. 3
AFM-IR spectra of the PTD and ITD in normal and DGI-II coronal dentin
Fig. 4
Fig. 4
Young’s Modulus and nanoindentation mapping of the PTD and ITD in normal and DGI-II coronal dentin
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Kim J-W, Simmer JP. Hereditary dentin defects. J Dent Res. 2007;86:392–9. 10.1177/154405910708600502. - PubMed
    1. Shields ED, Bixler D, el-Kafrawy AM. A proposed classification for heritable human dentine defects with a description of a new entity. Arch Oral Biol. 1973;18:543–53. 10.1016/0003-9969(73)90075-7. - PubMed
    1. Barron MJ, McDonnell ST, Mackie I, Dixon MJ. Hereditary dentine disorders: dentinogenesis imperfecta and dentine dysplasia. Orphanet J Rare Dis. 2008;3:31. 10.1186/1750-1172-3-31. - PMC - PubMed
    1. Mao J, Wang L, Jiang Y, et al. Nanoscopic wear behavior of dentinogenesis imperfecta type II tooth dentin. J Mech Behav Biomed Mater. 2021;120:104585. 10.1016/j.jmbbm.2021.104585. - PubMed
    1. Zhang X, Zhao J, Li C, et al. DSPP mutation in dentinogenesis imperfecta shields type II. Nat Genet. 2001;27:151–2. 10.1038/84765. - PubMed

LinkOut - more resources