<p>The inorganic matter in human tooth enamel (HTE) is related to the hexagonal unit cell of hydroxyapatite (HAP), but carbon, magnesium, and sodium are also detected by Energy-Dispersive X-ray spectroscopy (EDS) in addition to HAP’s elements. These elements are attributed to ionic substitutions within the HAP unit cell, where Ca²⁺ ions are partially replaced by Mg²⁺ and Na⁺ ions, and the PO₄³⁻ and OH⁻ ions are partially replaced by carbonate (CO₃²⁻) ions. Simulations of HAP-related structures have indicated that these substitutions induce a slight distortion, transforming the unit cell from hexagonal to triclinic. Therefore, with the aim of recovering the hexagonal system for HTE, a <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(\sqrt{3}\times \sqrt{3}\times 1\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msqrt> <mn>3</mn> </msqrt> <mo>×</mo> <msqrt> <mn>3</mn> </msqrt> <mo>×</mo> <mn>1</mn> </mrow> </math></EquationSource> </InlineEquation> hexagonal supercell based on the HAP unit cell including the additional CO₃²⁻, Mg²⁺ and Na⁺ ions was generated. However, the crystallographic elements observed in the convergent beam electron diffraction (CBED) patterns indicate that the system remains triclinic.</p> Graphic Abstract <p></p>