AH Plus vs. Bioceramic Sealer: Properties and Patient Benefits

AH Plus and bioceramic sealers represent two fundamentally different approaches to filling the space between root canal walls and the core filling material, and the choice between them is less clear-cut than marketing materials for either product suggest. AH Plus, the long-standing epoxy resin-based benchmark, offers excellent dimensional stability and low solubility, while calcium silicate-based bioceramic sealers bring genuine bioactivity and a friendlier biological profile. Clinical success rates at one year, though, are virtually identical for both categories, which means the practical differences show up in subtler places that still matter to patients and clinicians.

How the Two Materials Actually Work

AH Plus sets through a slow polymerization reaction between epoxy resin amines and high-molecular-weight compounds including bisphenol A and bisphenol F. That chemical process is self-contained: once the base and catalyst are mixed, the material hardens on its own schedule regardless of the surrounding environment.¹ The result is a rigid, resin-like plug that bonds mechanically to both dentin and gutta-percha.

Bioceramic sealers take the opposite approach. They are calcium silicate–phosphate materials that hydrate through what chemists call a pozzolanic reaction: calcium hydroxide dissociates into calcium and hydroxyl ions, which then react with silicate oxides and phosphate in the paste. The reaction products include calcium phosphate silicate and, eventually, hydroxyapatite-like crystals on the material’s surface.² That last detail is the headline feature: the sealer does not just sit inertly inside the canal. It actively deposits mineral that resembles tooth structure, creating a chemical bond with dentin rather than a purely friction-based one.

This chemistry difference has a practical consequence that clinicians deal with every day. AH Plus needs a dry canal to perform well. Bioceramic sealers need moisture to set at all, because their hydration reaction depends on it. The best bond strength for a bioceramic sealer has been found in slightly moist canals rather than bone-dry ones.³ Too much moisture, however, can interfere with setting, so the sweet spot matters. One study found that even “dry” canals still retained enough residual moisture in the dentinal tubules to support the reaction, making standard paper-point drying a reasonable protocol for bioceramic sealers.⁴

Biocompatibility and Cell-Level Safety

One of the strongest arguments for bioceramic sealers is their biological friendliness. In cell culture studies, AH Plus consistently shows higher toxicity to human cells than bioceramic alternatives. A 2025 study comparing AH Plus with Well-Root ST and AH Plus Bioceramic Sealer (a newer hybrid product from the same manufacturer) found that AH Plus was more toxic to cells at every time point measured over 72 hours. At the genetic level, AH Plus also caused more DNA damage than either bioceramic product.⁵

That said, the picture is not uniformly rosy for all bioceramics. A separate study testing several bioceramic formulations (BioRoot Flow, BioRoot RCS, TotalFill BC, and AH Plus Bioceramic Sealer) found that BioRoot Flow and BioRoot RCS significantly reduced cell viability and triggered apoptosis in gum tissue cells after 48 hours. AH Plus Bioceramic Sealer and TotalFill BC Sealer performed better, with TotalFill BC showing no significant DNA damage compared to controls in one cell line.⁶ So “bioceramic” is a category, not a single product, and formulations within the category vary meaningfully in how gently they treat surrounding tissues.

Bioceramic sealers also release calcium ions and raise the local pH, creating an alkaline environment. AH Plus Bioceramic Sealer, for instance, showed the highest alkalinity and calcium ion release among sealers tested in one head-to-head comparison.⁷ That alkalinity is part of the antimicrobial story, discussed below, and it also promotes the mineralization that helps the sealer integrate with natural tooth structure.

Killing Bacteria Inside the Canal

Residual bacteria, particularly Enterococcus faecalis, are the usual suspects when a root canal treatment fails. Both AH Plus and bioceramic sealers have some antibacterial effect, but the balance of evidence favors bioceramics against this organism. In a direct comparison, TotalFill Bioceramic Sealer showed the highest antibacterial activity, followed by BioRoot RCS and MTA Fillapex, with AH Plus trailing behind all three.⁸ Another study using matured biofilms on actual root canal dentin found that EndoSequence BC Sealer killed significantly more E. faecalis than AH Plus.⁹

The story gets more complicated with Candida albicans, the fungal organism sometimes involved in persistent infections. One study found that an MTA-based bioceramic sealer (Endoseal MTA) performed well against E. faecalis at 24 hours, but AH Plus actually produced a greater reduction in Candida colonies at two weeks.¹⁰ In other words, neither sealer class is universally superior against every microorganism. The high pH environment that bioceramics create appears to be especially effective against bacteria, while AH Plus’s resin chemistry may hold an edge against certain fungi.

Bond Strength, Tubule Penetration, and Solubility

When clinicians talk about how well a sealer “sticks,” they are usually referring to push-out bond strength, a lab test that measures how much force is needed to dislodge the sealer from the canal wall. The results here consistently depend on what irrigation protocol was used before placing the sealer. In one well-controlled study, the epoxy resin sealer showed higher bond strength across all groups, while the bioceramic sealer achieved greater penetration into the tiny tubules running through dentin.¹¹ Deeper tubule penetration is considered advantageous because it expands the sealer’s contact with tooth structure and puts antimicrobial material where bacteria are hiding.

Bond strength for bioceramic sealers is more sensitive to irrigation choices than AH Plus is. When QMix solution was used as a final rinse, the bioceramic sealer achieved the highest bond strength of any combination tested, while AH Plus bond strength remained relatively stable regardless of the rinse used.¹² Continuous chelation with an agent called Dual Rinse HEDP significantly increased AH Plus bond strength but had no effect on AH Plus Bioceramic Sealer.¹³ The takeaway for clinicians is that bioceramic sealers are pickier about technique. With the right protocol they can match or beat AH Plus, but a careless rinse choice can leave them underperforming.

Solubility is where AH Plus retains a clear advantage. An in vitro study comparing AH Plus, EndoSequence BC, and Bio-C Sealer found that AH Plus had the lowest solubility of the three, and that both simulated aging and thermal cycling increased the solubility of all sealers, with the bioceramic sealers more affected by those stresses.¹⁴ In practical terms, this means bioceramic sealers may lose slightly more volume over years of service, though the clinical significance of that difference is debated since the mineral deposition bioceramics promote could partially compensate.

What Patients Actually Feel After Treatment

If you are a patient, the property you care about most is probably whether one sealer hurts more than the other afterward. The clinical trial data here is reassuring regardless of which sealer your dentist uses. A randomized trial in molars found very low postoperative pain in both groups. The AH Plus group had slightly higher pain intensity and analgesic use in the first 24 hours, but there were no differences in bite sensitivity or quality of life impact.¹⁵ A separate double-blinded trial comparing AH Plus with iRoot SP (a bioceramic sealer) in mandibular molars found no significant difference in postoperative pain occurrence or intensity between the two groups, with pain in both groups declining after 48 hours.¹⁶

Long-term success rates tell a similar story. A retrospective study of 237 patients compared AH Plus and AH Plus Bioceramic Sealer and found success rates of about 94% for both.¹⁷ A randomized controlled trial looking specifically at maxillary incisors with large periapical lesions also found no significant difference in healing between AH Plus with lateral compaction and a bioceramic sealer with a single-cone technique, with both groups achieving high success rates up to 12 months.¹⁸ For patients, the practical message is straightforward: you are not getting a worse outcome with either sealer, so the sealer choice alone is unlikely to determine whether your root canal succeeds.

What Happens If Retreatment Becomes Necessary

This is where the conversation shifts in AH Plus’s favor, at least historically. If a root canal fails and needs to be redone, the old filling material must come out. Neither sealer class allows for perfectly clean removal. A micro-CT study of retreatability found that no group achieved complete removal of the filling material whether BC Sealer, BC Sealer HiFlow, or AH Plus was used.¹⁹ That finding has been confirmed repeatedly: another study using solvents, retreatment files, and even diode laser reached the same conclusion for both sealer types.²⁰

Interestingly, one study found that BC Sealer actually left less residual filling material than AH Plus during retreatment. Adding ultrasonic instrumentation significantly improved removal for both sealers and was highlighted as a particularly valuable tool for bioceramic cases.²¹ The concern that bioceramic sealers are dramatically harder to retreat than AH Plus is not as firmly supported as it used to be. Neither is easy to remove completely, but modern instrumentation techniques are narrowing the gap. The broader review literature still flags retreatability as an area of concern for bioceramics, though, which keeps some clinicians cautious.²²

Using Bioceramic Sealers with Warm Techniques

Many endodontists prefer warm vertical compaction, which uses heated instruments to soften gutta-percha and improve its adaptation to the canal walls. Early bioceramic sealers were designed strictly for cold techniques, but newer formulations have been developed for warm use. A scoping review found that EndoSequence BC HiFlow and TotalFill HiFlow retained their chemical structure, setting time, and cytotoxicity profile even after exposure to the temperatures used in warm vertical compaction. HiFlow versions also showed better flow characteristics and radiopacity at elevated temperatures.²³ While the chemistry of both sealers was modified during heating, both recovered on cooling.²⁴ Clinicians who are invested in warm techniques no longer need to rule out bioceramic sealers, though they should verify that the specific product they are using is labeled for that purpose.

Mineralization and the Dentin Interface

The bioactivity argument is perhaps the most compelling theoretical advantage of bioceramic sealers. When a bioceramic sealer like iRoot SP is placed in a canal dried with paper points and allowed to interact with surrounding dentin, new mineral deposits form on its surface and grow along the dentinal tubules. Energy-dispersive spectroscopy analysis has shown these deposits contain calcium, phosphorus, oxygen, silicon, and carbon, with a calcium-to-phosphorus ratio close to that of hydroxyapatite.²⁵ The same study found that drying the canal with ethanol instead of paper points essentially prevented this mineralization, underscoring how technique-sensitive the bioactivity advantage really is.

AH Plus does not produce this kind of mineral deposition. It bonds to dentin through micromechanical retention and chemical interaction with amino groups in collagen, but it does not stimulate the tooth to lay down new mineral. Whether the bioceramic mineralization effect translates to better long-term sealing or fracture resistance in a living patient remains an open question, since the clinical success rates for both sealers are so similar at the time points measured so far.

Tooth Discoloration

Root canal sealers can cause visible darkening of the treated tooth, which matters most in anterior teeth where aesthetics are a concern. A systematic review found that after three years, calcium silicate-based sealers like BioRoot RCS and TotalFill BC showed discoloration within the acceptable range and had lower color-change values than AH Plus.²⁶ Some studies at shorter time points found no significant difference between sealer types, and one noted that a calcium silicate sealer actually showed the highest color change at one and three months, though the difference was not statistically significant.²⁷ Overall, the discoloration story slightly favors bioceramics over the long haul, but neither category is completely stain-free.

When Sealer Residue Meets a Future Restoration

After a root canal, the tooth usually receives a composite filling or crown. If sealer residue is left on the coronal dentin surface, it can interfere with the bond strength of the composite. Research suggests that bioceramic sealer residue may be more problematic in this regard than AH Plus residue. One study found that a bioceramic sealer (Bioserra) contaminated groups showed lower bond strength values than AH Plus contaminated groups across several cleaning methods.²⁸

The good news is that proper cleanup eliminates most of the difference. Ultrasonic activation for as little as 15 seconds restored bond strength to near-control levels in healthy dentin contaminated with bioceramic sealer. In dentin from patients with diabetes, 30 seconds of ultrasonic treatment was needed to achieve equivalent results.²⁹ Simply wiping the surface with a dry cotton pellet was the least effective cleaning method. For patients, this means the choice of sealer matters less than whether the clinician takes the extra step of properly cleaning the chamber before placing the final restoration.

Nerve Injury from Sealer Extrusion

A risk that applies to both sealer types is extrusion beyond the root apex into nearby anatomical structures, particularly the mandibular canal that carries the inferior alveolar nerve. Case reports document permanent numbness of the lower lip and chin (paresthesia) after AH Plus was pushed into the mandibular canal during treatment of a lower molar.³⁰ An essentially identical complication has been reported with bioceramic sealer, where extruded material reached the interior of the mandibular canal and caused permanent labiomandibular paresthesia.³¹ The complication is rare but serious, and neither sealer category is immune to it. The risk has more to do with overfilling technique and the proximity of the root apex to the nerve than with the sealer’s chemistry. Potential neurotoxicity remains flagged as a concern specifically for bioceramic sealers in review literature, even though case reports exist for both types.²²

The Simplified Single-Cone Approach

One genuine workflow benefit of bioceramic sealers is that they pair naturally with a single-cone obturation technique, where one well-fitted gutta-percha cone is coated in sealer and placed in the canal. AH Plus has traditionally been used with lateral or warm vertical compaction, both of which require more instruments and more chair time. The randomized trial on maxillary incisors with large periapical lesions found equivalent success rates when comparing AH Plus with lateral compaction to a bioceramic sealer with a single-cone technique.¹⁸ For clinicians, the practical payoff is a faster, simpler filling procedure without sacrificing outcomes. For patients, a shorter appointment for the same result is an easy win.

That said, AH Plus Bioceramic Sealer and newer HiFlow bioceramic formulations are increasingly blurring this distinction. Clinicians who prefer warm compaction can now select a bioceramic product designed for that technique, while those who want the simplicity of single-cone can stick with a standard bioceramic. The sealer market has moved away from a clean dichotomy toward a spectrum of options within each chemistry.

Cost and Shelf-Life Considerations

AH Plus is sold as a two-paste system that is mixed before use and has a relatively long shelf life. Bioceramic sealers are typically premixed and supplied in syringes, which is more convenient but introduces a shelf-life constraint since the material must not be exposed to moisture before it is placed in the canal. Premixed syringes that have been stored improperly can begin to set inside the syringe, rendering the product unusable. Bioceramic sealers also tend to carry a higher per-unit price than AH Plus, though the exact difference varies by product and market. If the bioceramic allows a simpler single-cone technique, the reduced procedural cost in instrument wear and chair time can offset part of the material cost. No published cost-effectiveness analysis directly compares the two categories in a clinical setting, so any economic argument remains rough estimation for now.