Biodentine vs. Dycal For Pulp Capping
A Case Selection Guide

The primary difference lies in their composition and mechanism: Biodentine is a tricalcium silicate-based bioceramic that actively stimulates tertiary dentin formation, whereas Dycal is a traditional calcium hydroxide liner that relies on its high pH for antibacterial effects and passive stimulation.

Biodentine's tricalcium silicate composition hydrates to form a crystalline structure that chemically bonds to dentin, creating a tight seal and releasing calcium hydroxide to promote a high-quality dentin bridge. Dycal, a two-paste system, sets via a chelation reaction, providing a high pH of approximately 11-12 which is bacteriostatic but offers lower compressive strength and can degrade over time, compromising the long-term seal. This makes it less suitable under restorations subject to high occlusal forces.

• Sealing Ability: Biodentine creates a gap-free, mineral-infiltrated zone, minimizing microleakage. Dycal is prone to dissolution and marginal breakdown over months.
• Compressive Strength: Biodentine reaches ~300 MPa, comparable to dentin, allowing its use as a temporary restoration. Dycal's strength is significantly lower, typically under 20 MPa.
• Bioactivity: Biodentine actively releases calcium ions and promotes apatite formation, leading to a more organized and thicker dentin bridge.
• Setting Time: Dycal sets rapidly in 2-3 minutes. Biodentine requires an initial set of 10-12 minutes before the final restoration can be placed.

Biodentine is the material of choice for direct pulp capping in cases with large mechanical or carious exposures (>1.5 mm) in vital, asymptomatic teeth, where a superior long-term seal and robust dentin bridge formation are critical.

Its high compressive strength and excellent sealing ability make it ideal for situations where the final restoration might be delayed or where the overlying restorative material could exert significant stress. The bioactive properties provide a more predictable healing response for larger exposures, minimizing the risk of post-operative sensitivity and pulp necrosis. A well-stocked inventory of endodontic products is crucial for managing these demanding vital pulp therapy procedures.

• Large Pulp Exposures: For exposures >1.5 mm in diameter, Biodentine's biological response and seal are superior to traditional liners.
• Deep Carious Lesions: When a carious exposure is encountered during excavation in a tooth with no history of spontaneous or lingering pain.
• Traumatic Exposures: In young, permanent teeth with open apices where preserving vitality is paramount for continued root development (apexogenesis).
• Dentin Replacement: Use as a base to replace significant amounts of lost dentin structure under a final composite or crown restoration.

Dycal remains a practical choice for small, iatrogenic (mechanical) pinpoint exposures in otherwise healthy teeth where speed and simplicity are prioritized over long-term structural support.

Its rapid 2-3 minute setting time is highly advantageous in a busy practice, especially for minor exposures encountered during routine cavity preparation. When the exposure is minimal (<0.5 mm) and bleeding is easily controlled, Dycal's high pH is sufficient to provide an antibacterial barrier and stimulate a localized repair response without the longer setting time and higher cost of Biodentine. A failure of pulp capping may necessitate endodontic therapy using instruments like rotary files and endomotors.

• Pinpoint Mechanical Exposures: Accidental exposures <0.5 mm during cavity preparation in an asymptomatic tooth.
• Indirect Pulp Capping: As a liner over a thin layer of remaining sound dentin when you are close to the pulp but not exposed.
• Time-Sensitive Procedures: In a high-volume setting where the 12-minute initial set of Biodentine would significantly disrupt workflow.
• Cost-Constrained Cases: When budget is a primary consideration and the clinical indication is for a simple, low-risk exposure under a stable restoration.

The depth of the carious lesion directly dictates material selection: shallow to moderate lesions may not require a liner, deep lesions nearing the pulp are ideal for indirect capping with Dycal or a GI liner, and frank carious exposures demand a bioactive material like Biodentine.

For deep lesions where a thin layer of affected or sound dentin remains (e.g., <0.5 mm Remaining Dentin Thickness), the goal is to protect the pulp and promote remineralization. However, once the pulp is exposed by caries, the inflammatory state and bacterial contamination are higher. This scenario requires a material like Biodentine that can create a superior bacterial seal and more predictably stimulate a reparative dentin bridge, reducing the likelihood of failure and the subsequent need for root canal therapy with root canal sealers.

• Indirect Pulp Cap: Remaining dentin is <0.5 mm thick but intact. Dycal or Glass Ionomer is indicated.
• Small Carious Exposure (<1.5 mm): The pulp is breached during caries removal. Biodentine is strongly recommended due to its superior sealing ability and bioactivity.
• Large Carious Exposure (>1.5 mm): Significant pulp exposure. Biodentine is the gold standard; endodontic therapy is a likely alternative if symptoms are present.
• Reversible Pulpitis: The diagnosis must confirm reversible pulpitis. If signs of irreversible pulpitis (spontaneous pain, lingering pain to cold) exist, pulp capping is contraindicated.