**5. Conclusions**

In conclusion, the synthesis that is proposed in this study promoted the anchorage of AgNP with the CaGP, and the nanocomposites produced using sodium citrate as reducing agen<sup>t</sup> were effective against both of the microorganisms tested. Also, the highlight of our study was that the addition of CaGP to AgNP expressively reduced the MIC values when it was compared with the MIC values of AgNP by itself. These promising results strongly encourage further studies with the purpose of producing biomaterials with antimicrobial and remineralizing functions in the near future, particularly in the dental field.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2079-6382/7/3/52/s1, Figure S1: UV–Visible spectrum of Ag-CaGP nanocomposites, Figure S2: X-ray diffraction pattern of Ag-CaGP nanocomposites, Figure S3: TEM images of B4 Ag-CaGP nanocomposite, Figure S4: SEM images and energy-dispersive X-ray sprectroscopy (EDS) mapping in 2D elements issuance Si Kα,OK<sup>α</sup>,PKα,Ca Kα and Ag Kα false color. Analysis of the distribution of silver nanoparticles in the Ag-CaGP nanocomposites B1, B2 and B3, Figure S5: SEM images and EDS mapping in 2D elements issuance Si Kα,OK<sup>α</sup>,PKα,Ca Kα and AgKα false color. Analysis of the distribution of silver in the Ag-CaGP nanocomposites B5, B6 and B7, Figure S6: SEM images and EDS mapping in 2D elements issuance Si Kα,OK<sup>α</sup>,PKα,Ca Kα and Ag Kα false color. Analysis of the distribution of silver nanoparticles in the Ag-CaGP nanocomposites C1, C2 and C3.

**Author Contributions:** G.L.F., D.B.B., A.C.B.D. conceived and designed the experiments; G.L.F., R.A.F., J.G.d.A., J.A.S.S. performed the experiments; G.L.F., D.B.B., A.C.B.D., D.R.M. analyzed the data; F.N.d.S.N., L.F.G., E.R.C. contributed reagents/materials/analysis tools; G.L.F., D.B.B., A.M.A.H. wrote the paper.

**Funding:** This study was supported by: São Paulo Research Foundation (FAPESP, Processes 2013/24200-9 and 2014/08648-2), Brazil; and Coordination for the Improvement of Higher Education Personnel (Capes, Process 88881.030445/2013-01), Brazil.

**Conflicts of Interest:** The authors declare no conflict of interest. The founding sponsors had no role in the design of the study in the role on the design of the study in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.
