Founding preview — simpleprot is free for everyone, for a limited time. When memberships open, free accounts keep just the 10 demo protocols (no Materials). Lock in founding pricing →
When you want a 2-step mild self-etch (10-MDP) adhesive for a direct composite — especially non-carious cervical lesions (NCCLs) and routine Class I/II cavities — where the bulk of the bonding substrate is cut dentine and you want low postoperative sensitivity with a durable, well-documented long-term dentine bond.
⚑ adhesion mandatory
Selectively etch the enamel margins first with 37% phosphoric acid (15-30 s, then rinse), then apply the self-etch primer + bond to the whole prep. Do NOT etch the cut dentine — leave it for the mild self-etch primer, whose 10-MDP forms a durable MDP-Ca bond and a stable hybrid layer. Phosphoric acid on dentine over-demineralises and removes the smear layer the self-etch chemistry is designed to incorporate, which is what drives postoperative sensitivity and degrades the dentine bond.
A 2-step mild 10-MDP self-etch adhesive (Clearfil SE Bond 2, Kuraray Noritake) after selective phosphoric-acid etch of the enamel margins only: scrub primer onto cut dentine and enamel, gently air-dry, then apply bond and light-cure. Low postoperative sensitivity; durable MDP–Ca dentine bond.
▢Shade guide — select shade BEFORE isolation (teeth dehydrate and lighten under dam)
▢Local anaesthetic if needed
▢Rubber dam kit (preferred) or cotton rolls + high-volume suction
▢Diamond/round burs + caries indicator or slow round bur for cavity prep
▢37% phosphoric acid etch (gel) + microbrushes — for selective ENAMEL etch only
▢Clearfil SE Bond 2 — primer + bond bottles (or chosen 2-step self-etch system)
▢Disposable applicators / microbrushes + a clean well for dispensing
▢Curing light (verify output with a radiometer) + light-shield
▢Oil-free air source for gentle solvent evaporation / air-thinning
▢Composite of choice + placement and finishing/polishing instruments
The full kit — swap any item for alternatives; a preset just fills the swappable ones.
1Select shade before isolation — teeth dehydrate and lighten once the dam is on.
2Anaesthetise if needed, prepare/clean the cavity, and isolate — rubber dam preferred; cotton rolls + high-volume suction are an acceptable alternative. Keep the field, especially the cervical margin, dry through every adhesive step.
3Selectively etch the ENAMEL margins only — 37% phosphoric acid 15-30 s, then rinse thoroughly (~15 s). Place the gel deliberately so it stays on enamel and off the cut dentine. Across NCCL trials this selective enamel etch lowers marginal discoloration and reduces retention loss versus self-etching the enamel too.
TIP · Selectively etch the enamel margins even with a 'self-etch' adhesive. A systematic review and meta-analysis of NCCL trials found that selective enamel etching before a self-etch adhesive significantly lowers marginal discoloration and marginal-adaptation failure across follow-up, and reduced retention loss at 3 years. Keep the phosphoric acid deliberately on enamel and rinse it off before priming.
TIP · This isn't a new or unproven approach: in a 13-year randomized controlled trial in non-carious cervical lesions, the original Clearfil SE Bond stayed clinically excellent, with ~86-93% success and only a handful of retention/marginal failures — and selective enamel etching gave a small extra edge on marginal integrity and discoloration. A durable dentine bond plus etched enamel margins is what buys these restorations their years.
4Do NOT etch the cut dentine — leave it for the self-etch primer. Phosphoric acid on dentine strips the smear layer and over-demineralises, leaving collagen the resin can't fully envelope; the mild self-etch chemistry is designed to keep dentine demineralisation shallow and self-limiting, which protects the bond and keeps sensitivity low.
TIP · Don't phosphoric-etch the cut dentine with a mild self-etch system. The mild primer keeps dentine demineralisation shallow and incorporates the smear layer, so resin fully envelopes the exposed collagen. Over-etched dentine is the classic route to a weaker, leakier bond — and clinically, the self-etch strategy carries no more postoperative sensitivity than etch-and-rinse, so there's nothing to gain by etching dentine.
5Apply Clearfil SE Bond 2primer — dispense fresh, scrub the primer into the cut dentine and enamel for the full IFU time (Clearfil SE Bond 2: ~20 s), agitating actively. Active rubbing increases MDP-Ca nano-layering and the chemical bond.
TIP · The durability of these adhesives is chemistry, not just micromechanics. The 10-MDP functional monomer ionically bonds to hydroxyapatite calcium, forming stable MDP-Ca salts that self-assemble into 'nano-layers' at the dentine interface — shown specifically for Clearfil SE Bond. The long carbon-chain spacer makes those salts more stable than shorter-chain monomers, which helps explain the better documented bond durability of MDP-based adhesives. Scrub the primer in actively and give it its full working time.
6Gently air-dry the primer per IFU to evaporate the solvent — use a mild, oil-free air stream until the surface looks evenly matte and no longer mobile. Under-drying leaves residual solvent/water that weakens the bond.
7Apply the bond resin in a uniform film, thin it gently with air to avoid pooling (especially in line angles and the gingival floor), then light-cure per IFU. Confirm the bond reaches the entire margin, including the cervical floor of any box.
8Place and cure the composite of choice in increments to its rated depth, contour, finish and polish, then check occlusion. Removing the dam, verify margins are flush and smooth.