Monetite mineral
Monetite is the anhydrous calcium hydrogen-phosphate mineral CaHPO4, written Ca(PO3OH) in the September 2026 IMA list. It is triclinic and distinct from brushite, CaHPO4.2H2O, and from a whole dental resin composite. The IMA entry has grandfathered status G and original-description year 1882, not a unique approval accession. The curated laboratory evidence concerns source-assigned monetite on synthetic brushite-containing composite surfaces following live biofilm or cell-free spent-broth exposure; it does not establish natural occurrence in those specimens or pure-mineral recovery. No criticality designation is inherited from calcium or phosphorus.
Microbial & Biochemical Mechanisms (1)
Monetite-assigned surface phase after biofilm and filtered spent-broth challenge
biomineralization
Microbial
Associated Organisms:
Streptococcus mutans (NCBITaxon:1309)
The study assigns monetite alongside residual brushite on RBC-20 and RBC-40 disks after a Streptococcus mutans biofilm challenge and after a separate sterile challenge using filtered broth from the biofilm experiment. Brushite conversion and dissolution followed by reprecipitation are proposed routes, not distinguished kinetically. Monetite formation in the cell-free arm means direct contact with living cells is not required under those tested conditions; it does not exclude effects of microbial metabolites in that broth.
Experimental Context & Analytical Limits:
Laboratory disk assay, distinct from the separate two-week restored-tooth experiment. Experimental resin composites contained 20 or 40 wt.% TEGDMA-functionalized brushite plus respectively 40 or 20 wt.% barium glass; total filler was 60 wt.%. RBC-0 had 60 wt.% barium glass and no added brushite. Light-cured 6 mm diameter, 2 mm high polished disks were chemiclave-sterilized and conditioned for one week in daily-changed artificial saliva at pH 7 (1W). After a 24-hour salivary-pellicle incubation at 37 degrees C, S. mutans ATCC 35668 was inoculated in sucrose-supplemented BHI, held statically for four hours at 37 degrees C in 5% CO2, then exposed to modified artificial saliva flowing at 20 mL/h for 48 hours. BIO disks were PBS-rinsed, sonicated at reported 40 W for 10 minutes and microbrush-cleaned to remove the biofilm before material analyses. The ACID arm used the same bioreactor setup under sterile conditions with filter-sterile effluent from previous BIO runs, reported pH 4.2 +/- 0.1. It is cell-free spent medium, not fresh inorganic acid or a culture-free chemical provenance control. Nondestructive surface XRD is distinct from the separately described heating during thermogravimetry. No phase-specific recovered mass, phosphorus balance, in situ hydration measurement or industrial deployment is reported.
Laboratory disk assay, distinct from the separate two-week restored-tooth experiment. Experimental resin composites contained 20 or 40 wt.% TEGDMA-functionalized brushite plus respectively 40 or 20 wt.% barium glass; total filler was 60 wt.%. RBC-0 had 60 wt.% barium glass and no added brushite. Light-cured 6 mm diameter, 2 mm high polished disks were chemiclave-sterilized and conditioned for one week in daily-changed artificial saliva at pH 7 (1W). After a 24-hour salivary-pellicle incubation at 37 degrees C, S. mutans ATCC 35668 was inoculated in sucrose-supplemented BHI, held statically for four hours at 37 degrees C in 5% CO2, then exposed to modified artificial saliva flowing at 20 mL/h for 48 hours. BIO disks were PBS-rinsed, sonicated at reported 40 W for 10 minutes and microbrush-cleaned to remove the biofilm before material analyses. The ACID arm used the same bioreactor setup under sterile conditions with filter-sterile effluent from previous BIO runs, reported pH 4.2 +/- 0.1. It is cell-free spent medium, not fresh inorganic acid or a culture-free chemical provenance control. Nondestructive surface XRD is distinct from the separately described heating during thermogravimetry. No phase-specific recovered mass, phosphorus balance, in situ hydration measurement or industrial deployment is reported.
Curated Evidence Points:
Support
Source:
ionescu2022
Methods 2.5 and 2.7.3, Results 3.1, Figure 8 and Table 1 (PDF page 12) identify brushite in the 1W RBC-20 and RBC-40 surfaces and additional monetite in both corresponding BIO and ACID surfaces. RBC-0 is X-ray amorphous in all three treatments. The original diffractograms show B and M assignments; the crystalline material remains mixed. Methods says a total of three specimens were analyzed by XRD, without an unambiguous per-arm allocation; the larger microbiology sample counts must not be substituted as diffraction replication.
Partial
Source:
ionescu2022
Both BIO and ACID arms contain monetite, so the experiment does not show that living cells or direct attachment are necessary for this phase. Filtered effluent retains microbial products and its composition is not independently matched by a fresh-acid control. Figure 8/Table 1 are qualitative phase assignments, with no Rietveld phase fractions. Table 1 gives monetite a single + in both BIO materials and ++ only in RBC-40 ACID; the general Results statement about more monetite in RBC-40 does not establish a quantified BIO-arm difference.
Partial
Source:
ionescu2022
Table 2 and Figure 9 estimate residual brushite from thermal mass loss, not monetite yield or phosphorus recovery. Loss of brushite can reflect dissolution as well as transformation. Discussion pages 16-17 proposes brushite decomposition or dissolution/reprecipitation and a contribution beyond acid production, but these pathways are not separately measured. The BIO cleaning treatment, unspecified wet-versus-dried XRD handling and absence of time-resolved phase quantification constrain causality and timing.
Context_only
Source:
ionescu2022
The tooth micro-CT outcomes, biomass viability, buffering and biofilm ion analyses are different endpoints and are not monetite-specific clinical efficacy, mineral recovery or proof of the phase-transition mechanism. Data Availability says underlying datasets are available on reasonable request; no separate supplementary experiment is linked in the acquired complete PDF/JATS. The retrieved Europe PMC media archive contains the main figures only.
Context_only
Source:
ncbi_mutans
The species node resolves to Streptococcus mutans. The primary Methods and ATCC catalog supply the separate ATCC 35668 label; the species identifier does not prove the laboratory culture authenticity.
Sources & References
-
ima_2026_09: IMA-CNMNC. The New IMA List of Minerals, September 2026: definitions and Monetite row, PDF page 147. Retained original re-inspected on the access date.
https://cnmnc.units.it/files/editor/IMA_Master_List_(2026-09).pdf (accessed 2026-10-14) -
handbook_monetite: Handbook of Mineralogy, Monetite, version 1 (2001-2005). Complete one-page mineral identity and triclinic structure.
https://www.handbookofmineralogy.org/pdfs/monetite.pdf (accessed 2026-10-14) -
ionescu2022: Ionescu et al. (2022). TEGDMA-Functionalized Dicalcium Phosphate Dihydrate Resin-Based Composites Prevent Secondary Caries in an In Vitro Biofilm Model. Journal of Functional Biomaterials 13:232. Complete 19-page publisher PDF, JATS, all 13 figures and Tables 1-4; mineral claim centered on Methods 2.1-2.2, 2.5-2.7.3, Figure 8 and Table 1.
https://doi.org/10.3390/jfb13040232 (accessed 2026-10-14) -
ncbi_mutans: NCBI Taxonomy 1309: Streptococcus mutans, species node. This identifier does not itself identify a particular experimental stock.
https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=1309&mode=Info (accessed 2026-10-14) -
atcc_35668: ATCC catalog 35668: Streptococcus mutans Clarke. Culture collection identity corresponding to the strain label reported in Ionescu2022.
https://www.atcc.org/products/35668 (accessed 2026-10-14)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-14T17:19:40.181821Z |
codex (GPT-6; codex) | CREATE | Added monetite mineral identity and qualified surface phase formation after live S. mutans biofilm and cell-free spent-broth challenge, preserving mixed products, causal controls and unmeasured yield boundaries. |
Record source: data/records/monetite.yaml