Calcium-Phosphate Electrolyte Solution and Enamel Caries Formation In Vitro

Objective: A supersaturated calcium-phosphate electrolyte solution with an ionic strength and pH similar to saliva has been developed for mucositis treatment (Caphosol, EUSA Pharma, USA). This aqueous solution is composed of 2 components (solution A: dibasic and monobasic sodium phosphate; solution B: calcium chloride). Caphosol was evaluated for its effect on enamel caries formation in vitro. Methods: 20 human extracted teeth with caries-free enamel surfaces were divided into 3 tooth portions. This allowed for each tooth portion to undergo a different treatment: No Treatment Control (tooth portion 1); Caphosol (tooth portion 2); Sodium Fluoride Rinse (tooth portion 3: NaFl, ACT Fluoride Rinse, Chattem Inc, Chattanooga 37409). Caphosol group was rinsed twice daily for 120s followed by fresh synthetic saliva exposure over a 7d period. NaFl group was rinsed twice daily for 60s followed by fresh synthetic saliva exposure over a 7d period. Controls were rinsed with synthetic saliva replaced twice daily over a 7d period. Enamel caries were created in vitro (acidified gelatin gel, pH 4.25, 8wks). Three longitudinal sections were taken from each tooth portion for mean lesion depth measurement (water imbibition, polarized light, digital imaging capture/analysis system). Mean depths were compared among the groups (ANOVA, DMR). Results: Mean lesion depths were: No Treatment Control 425±39um; NaFl 331±28um; Caphosol 220±26um. Mean lesion depths were significantly less for Caphosol and NaFl compared with the no treatment control group (P<0.05, ANOVA, DMR). Caphosol had a mean lesion depth, which was significantly less compared with the NaFl group (P<0.05, ANOVA, DMR). Conclusions: A supersaturated calcium phosphate electrolyte solution with an ionic strength and pH similar to saliva significantly reduced in vitro enamel caries extent compared with sodium fluoride rinsing. Caphosol, a mucositis treatment rinse for cancer patients, may have the added benefit of enamel caries prevention in this high risk disease group.