MTA vs Biodentine for the Management of Open Apex in Immature Teeth

Raquel de Mello

Understanding Open Apex in Immature Permanent Teeth

Tooth development occurs in stages. First, the crown forms and then the root develops. Even after a tooth erupts into the mouth, the root is still incomplete and usually takes about three years to finish developing.

When the natural process of root formation is interrupted, the root remains incomplete. This condition is known as incomplete rhizogenesis or open apex.

The most common causes of open apex include

• Dental trauma• Deep dental caries• Pulp necrosis in developing teeth

These situations create significant challenges for endodontic treatment.

Clinical Challenges of Treating Open Apex

Managing teeth with open apices presents several difficulties for dentists.

The major challenges include

• Difficulty performing effective root canal cleaning• Lack of an apical stop, which makes sealing the canal difficult• Thin root canal walls that increase the risk of fracture

Because of these challenges, traditional root canal treatment techniques cannot always be used successfully.

Apexification: The Traditional Approach

A common treatment strategy for nonvital immature teeth is apexification.

Apexification is a procedure designed to create an apical barrier that allows proper sealing of the root canal during endodontic treatment.

Historically, apexification was introduced in the 1960s using calcium hydroxide.

In this method

• Calcium hydroxide is placed inside the root canal• Over several months it stimulates formation of a calcified barrier• Once the barrier forms, the canal can be obturated with gutta percha

However, this technique often requires 4 to 6 months or longer and multiple clinical visits.

Evolution of Apexification Materials

Over the last two decades, several materials have been investigated to improve apexification outcomes.

These include

• Bone morphogenetic proteins• Mineral trioxide aggregate (MTA)• Biodentine• Resorbable ceramics• Freeze dried bone or dentin• Dentinal shavings

Among these options, MTA and Biodentine have become the most widely studied materials in modern endodontics.

Mineral Trioxide Aggregate (MTA)

MTA revolutionized apexification procedures because of its excellent biological properties.

Key advantages of MTA include

• Excellent sealing ability• High biocompatibility• Ability to stimulate hard tissue formation• Antimicrobial properties due to its high pH

MTA is composed primarily of

• Portland cement• Bismuth oxide for radiopacity• Gypsum

It is available in gray and white formulations.

Despite its advantages, MTA has several limitations

• Long setting time (2 to 3 hours)• Difficult handling characteristics• Higher cost• Potential tooth discoloration

Biodentine: A New Generation Material

Biodentine was introduced in 2009 as a tricalcium silicate based cement designed to overcome some of the limitations of MTA.

Its composition includes

• Tricalcium silicate• Calcium carbonate• Zirconium oxide• Calcium chloride as a setting accelerator

Biodentine offers several important advantages.

Faster Setting Time

Biodentine sets in approximately 10 minutes, compared with 2 to 3 hours for MTA.

Improved Mechanical Properties

• Higher flexural strength (around 34 MPa compared with 14 MPa for MTA)• Increased microhardness over time

Biological Properties

• Good antimicrobial activity• Excellent biocompatibility with pulp and periodontal tissues• Ability to stimulate dentin bridge formation and tissue repair

Biodentine also promotes release of growth factors such as TGF beta 1, which supports regenerative processes.

Limitations of Both Materials

While both materials perform well clinically, each has limitations.

MTA limitations

• Long setting time• Handling difficulty• Risk of tooth discoloration• Higher cost

Biodentine limitations

• Slightly lower radiopacity• Potential washout risk during the initial setting phase

Clinical Applications

Both MTA and Biodentine have demonstrated successful results in several endodontic procedures, including

• Direct pulp capping• Pulpotomy in primary teeth• Pulpotomy in mature teeth• Apexification procedures

However, research specifically focused on open apex management in immature nonvital permanent teeth is still limited, highlighting the need for further clinical studies.

Findings from Current Literature

Several studies have compared the effectiveness of MTA and Biodentine for apexification procedures.

Key findings include

• Biodentine can achieve faster apical barrier formation• MTA shows excellent sealing and filling characteristics• Both materials support healing of apical lesions and tissue repair

Some studies also suggest that Biodentine may be particularly useful in cases requiring single visit treatments, especially in pediatric or uncooperative patients.

Clinical Implications

When selecting a material for apexification, dentists must consider several factors.

These include

• Treatment time• Handling characteristics• Biological properties• Clinical situation• Patient cooperation

Biodentine may offer practical advantages due to its faster setting time, while MTA remains a highly reliable material with strong evidence supporting its use.

Conclusion

Both MTA and Biodentine are effective materials for apexification procedures in immature permanent teeth with open apices.

Key conclusions from the literature include

• Biodentine allows faster apical filling and shorter treatment time• MTA offers excellent sealing ability and long term clinical success• Both materials demonstrate good biological compatibility and healing potential

However, current research still has limited evidence and potential bias, and further randomized clinical studies are needed to determine whether one material is definitively superior.

For now, both materials remain valuable tools in modern endodontic practice.