An 8 year old male patient complains of food lodgement in his lower right back teeth. On intra-oral examination, occlusal caries is seen with 46, which is non tender on percussion. Multiple restorations are also seen. The dentist decides to use Ariston pHc for the restoration. Which of the following ions is not released by this material?

**Core Concept**
The question tests the knowledge of dental restorative materials, specifically the properties of glass ionomer cements like Ariston pHc. Glass ionomer cements are used for their ability to release fluoride ions, which help in preventing secondary caries and promoting remineralization of tooth structure.

**Why the Correct Answer is Right**
Ariston pHc is a glass ionomer cement that releases fluoride ions, calcium ions, and aluminum ions. The release of fluoride ions is crucial for its cariostatic properties. Calcium ions help in the formation of a strong bond with the tooth structure, while aluminum ions are not released in significant amounts.

**Why Each Wrong Option is Incorrect**
* **Option A:** Fluoride ions are released by Ariston pHc, making it a suitable choice for restorations in non-vital teeth.
* **Option B:** Calcium ions are indeed released by Ariston pHc, contributing to its adhesive properties.
* **Option D:** Although the question stem doesn't specify, it's worth noting that other glass ionomer cements may release other ions like potassium and sodium.

**Clinical Pearl / High-Yield Fact**
Glass ionomer cements are suitable for non-vital teeth restorations due to their ability to release fluoride ions, which help in preventing secondary caries.

**Correct Answer:** C.

✓ Correct Answer: C. Phosphate