The TOR VM MD-Ring (N 1.167) is a specialized component within the TOR VM sectional matrix system, designed specifically to function as a separator and retainer during the restoration of large or complex posterior (Class II) cavities. The designation “MD” refers to its optimization for Molar and Deep cavity restorations, where greater separation force and enhanced stability are required.

Key Features and Function

Type and Construction
The MD-Ring is a sectional matrix separating ring, typically manufactured from highly resilient and durable metal, such as stainless steel or Nickel-Titanium (NiTi). These materials provide excellent elasticity, shape memory, and resistance to repeated sterilization and mechanical stress.

Primary Purpose
The core function of the MD-Ring is to generate separation force that compensates for the thickness of the matrix band. This ensures the formation of a tight, anatomically correct proximal contact once the ring is removed. Additionally, the ring plays a critical role in firmly retaining and adapting the sectional matrix band against the cervical margins of the tooth.

Tine Design
The MD-Ring is equipped with stout, anatomically shaped tines (forks). These tines are designed to fit securely over the sectional matrix band and engage the tooth structure either buccally and lingually or mesially and distally. The built-in spring tension of the ring provides the controlled separation necessary for optimal contact formation.

MD-Specific Configuration (Deep and Wide Cavities)

The N 1.167 MD-Ring features a higher, wider, and more resilient body compared to standard separating rings. This reinforced design makes it especially effective in:

• Molar restorations, where greater spring force is needed to span the larger tooth diameter.

• Deep cervical margins, where the ring can be placed deeper without collapsing the marginal ridge of the adjacent tooth, ensuring proper matrix adaptation over compromised gingival floors.

System Compatibility

The MD-Ring is designed for seamless integration with the TOR VM sectional matrix system. It is fully compatible with:

• TOR VM Sectional Matrices, such as those included in the N 1.198 kit.

• TOR VM Ring Forceps, such as N 1.099-2, which are used to safely expand and position the ring during clinical use.