Mesoporous, nanometric silica particles that can serve both as carrier and filler for fluoride were synthesized, and their release properties were later investigated. The flexural and compressive strengths performances of organic matrix and composite materials were evaluated using the tests defined in BS EN ISO 4049. From the Brunauer–Emmett–Teller results of the synthesized mesoporous silica particles, mesoporous SiO2 particles‐6 (MSP‐6) was preferred because it fits the MSP‐6 Type V isotherm model and has a highly mesoporous structure. The saturation points of MSP‐6 and R709 silica particles in terms of fluoride were determined as 180 min for MSP‐6 and 120 min for R709, respectively. The strength of composites prepared after the treatment of surface‐modified R709 silica particles with fluoride solution decreased, an increase was observed in the composites prepared after MSP‐6 particles were treated with fluoride solution. The porous silica particles caused a slight increase in the compressive strength of the composites. The standard deviations of the compression values of the fluorine‐containing composites F/R709 and F/MSP‐6 are quite low. The microhardness values of R709, F/R709, MSP6 and F/MSP6 samples were determined as 82.1 ± 8.59, 247.67 ± 12.32, 131.03 ± 10.98, and 218.8 ± 11.24, respectively. Especially considering the effect of chewing force the surface hardness of the composite is also directly related to the compressive strength. The increase in the compressive strength of the samples treated with fluoride confirms this result. A high rate of mesoporous structure silica particles was synthesized and could serve both as a carrier for fluoride and as a filler required by the material.