MTA or calcium hydroxide treatment for immature permanent teeth?

Abstract

Data sources

Pubmed, Medline and SCOPUS databases together with hand searching of the identified key journals' indexes, bibliographies, special issues and reference lists of identified articles were scanned to identify other potentially relevant articles.

Study selection

Controlled trials comparing calcium hydroxide versus MTA in immature permanent teeth where the aim was apexification where the outcome was evaluated by clinical symptoms and radiographic evidence and the formation of apical barrier was recorded, were included.

Data extraction and synthesis

Following data extraction consensus agreement was used to resolve disagreements. The principal measure of treatment effect was risk difference. The overall effect was tested by using Z score. Heterogeneity was tested by using the X² statistic and I square (I²). A fixed-effect model was used when the studies in the subgroup were sufficiently similar. A random-effects model was used in the summary analysis when there was heterogeneity between the subgroups.

Results

Two studies comparing the two materials with a total of 50 teeth met inclusion criteria. There was no significant difference in either the clinical or radiographic success between the two materials.

Conclusions

Calcium hydroxide and MTA may be suitable materials for the treatment of the immature teeth. However, more studies evaluating the factors influencing success and failure in teeth should be conducted.

Commentary

Mineral trioxide aggregate (MTA) was originally formulated as a root-end filling material for periradicular surgery.¹ The uses of MTA have since expanded to include the management of open apex cases; this was compared with calcium hydroxide (CH) in this article. The authors enumerated the challenges of managing non-vital immature teeth but since these are not deciduous teeth, the word ‘permanent’ should have been included, especially in the title.

To prevent overfilling during root canal treatment, CH is used for apexification, to induce an apical hard tissue barrier. However, MTA is used as an apical plug technique, to obviate the need to achieve apical barrier formation. The authors alluded to the subtle differences but the article's purpose was still stated as ‘...to compare the efficacy of calcium hydroxide and MTA for root-end induction....’

Only two studies met the inclusion criteria; the numbers treated are small and the follow-up relatively short. With El-Meligy & Avery, it is arguable that it is necessary to detect radiographically a barrier with MTA because if the periradicular lesion subsequently heals, this is indicative of a favourable outcome. With Pradhan et al., it is arguable that the lack of radiographic evidence of a hard tissue barrier should be considered a failure. Cases were assessed clinically and radiographically every four weeks; this is too soon and too frequent, especially in children.

In the discussion section, a valuable opportunity was missed to provide better coverage on the advantages of MTA over CH for managing open apex cases:²

• reduced number of treatment appointments

• less demanding on both clinical and patient time

• less stressful for the patient in terms of overall treatment duration

• reduced risk of root fracture

• reduced risk of re-infection due to loss of temporary filling.

A possible disadvantage is the greater cost of MTA, but it is more than offset by reduced treatment time.

In the reference list, the same paper was repeated three times (No. 6, 25 & 26). For a systematic review and meta-analysis article, it is unfortunate that a similar Cochrane review³ was not mentioned.

Even if barrier techniques continue to be practised, a recent review paper has concluded that MTA appears to overcome the shortcomings of, and may replace, CH.⁴ However, the advent of regenerative endodontic approaches has already encouraged a paradigm shift in the management of non-vital immature permanent teeth, heralding the beginning of the end of apexification.⁵