MTA- An Elixir for Root Perforations -A Short Review

 

Sisira Padavala¹, Dr. M.G. Aarthy²

¹BDS 3rd Year, Saveetha Dental College, Saveetha University, Chennai.

² Lecturer, Department of Conservative Dentistry and Endodontics, Saveetha Dental College, Saveetha University, Chennai.

 

ABSTRACT:

Root perforations are artificial connections between the root canal system and the periodontium and/or the oral cavity. They are undesired complications of endodontic treatment. It is very important to seal the site of perforation once diagnosed to minimize injury and prevent contamination of the surrounding periodontal attachment apparatus. Mineral trioxide aggregate is an endodontic cement used in treatment of root perforations and it is extremely biocompatible, hydrophilic and capable of stimulating the healing processes. Root perforation is a sign of endodontic failure and is the most common complication of endodontic therapy. The aim of this review is to understand the effectiveness of MTA in management of root perforations and to determine the prognosis of the treatment. Knowing the effectiveness of MTA may fasten the treatment and be more effective compared to other methods.

 

 

 

 

 

INTRODUCTION:

Root perforations are mechanical or pathological communication between the root canal system and the external tooth surface^[1]. Perforations occur as iatrogenic complications of endodontic treatment from access cavity preparation to post-space preparation. Misdirected bur during access cavity preparation causes root perforation. In molars with curved roots, excessive flaring at the apical thirds of root canals can lead to lateral root perforations. Strip perforations can occur during preparation of curved canals^[2].

 

The goal of perforation management is to arrest the inflammatory process and loss of tissue attachment by preserving the healthy tissue at the perforation site.Various materials have been used in managing perforations like zinc oxide-eugenol, IRM, calcium hydroxide, amalgam, composite resin and glass ionomer^[1,3].

 

Mineral trioxide aggregate is now the material of choice for perforation repair since its introduction by Mohamoud Taorabinejad at Loma Linda University, California, USA in 1993^[4].

 

MTA consists of fine hydrophilic particles of Tricalcium silicate, Tricalcium aluminate, Tricalcium oxide, Silicate oxide, Calcium sulphate dihydrate, tetracalcium aluminoferrite and small amounts of mineral oxides. MTA is non toxic, radio opaque, non absorbable, bacteriostatic and provides a good seal which makes it the material of choice for root perforation repair.It has a pH of 12.5 and sets in the presence of moisture in approximately 4 hours^[4,5].

 

In 2002, tooth colored MTA(White MTA) was marketed as a substitute for Gray MTA. It is off white in colour to provide a hue matched more closely to that of the colour of teeth. GMTA and WMTA differ in the concentrations of MgO, FeO and Al2O3. The absence of significant FeO in WMTA is the reason for the change in colour from grey to white^[4].

 

Classification of root perforations:^[6]

According to Fuss and Trope, the important factors in determining the success of a perforation repair are ,

·       The time interval between the occurrence of a perforation and it's repair,

·       The size of the perforation,

·       The location of the perforation.

 

The root perforations have been classified by Fuss and Trope in 1996.

Based on Location:

      I.          Coronal perforation-coronal to the level of crestal bone and epithelial attachment with minimal damage to the supporting tissues and easy access. The prognosis is Good.

    II.          Crestal perforation-at the level of epithelial attachment into the crestal bone. The prognosis is Questionable.

  III.          Apical perforation-apical to the crestal bone and the epithelial attachment. The prognosis is Good.

 

Based on Size:

      I.          Small perforation-associated with less tissue destruction. Good prognosis.

    II.          Large perforation-Poor prognosis.

 

Based on Time:

      I.          Fresh perforation-Good prognosis.

    II.          Old perforation-Poor prognosis.

 

In a multi rooted tooth, the  perforations occurring in the furcation may have a bad prognosis because of the overgrowth of the gingival epithelium towards the furcation area.

 

Properties of MTA:

·       Compressive strength of MTA was found to be at 40.0 MPa at 24hrs. The compressive strength of Grey MTA is greater than White MTA^[4,7].

·       MTA is highly biocompatible. It has good interaction with periapical and periradicular tissues. It is non mutagenic. It also has a good effect on cells collagen release mechanism^[1-8].

 

·       It induces the formation of dentin bridge. The tricalcium oxides of MTA react with the tissue fluids and form calcium hydroxide. Further more hard tissue is formed in a similar manner to that of calcium hydroxide. The dentin bridge is thus formed faster with good structural integrity^[4,9].

·       MTA does not react with other restorative materials. It does not affect the setting reaction of other resins like GIC or composite if placed over MTA^[4,10].

·       It has a mean radio opacity of 7.17 mm of equivalent thickness of aluminium. It is less radio opaque compared to IRM, Gutta percha^[4,7].

·       It is has a high antibacterial effect especially against E.faecalis and S.sanguis^[4,11].

·       It is a potential regenerative material. It activates the cementoblasts resulting cementogenesis. It also allows the growth of PDL fibers over its surface^[4,12].

·       MTA when set is insoluble. If it is exposed to water after setting it releases calcium hydroxide which may be responsible for its property of cementogenesis^[4,13].

·       MTA is has a good sealing ability. It has been found that about 4 mm thickness of MTA would suffice in order to give a good seal. This sealing ability of MTA is because of its expansion during setting especially in the presence of moisture. It is hydrophilic in nature^[4,14].

·       It has a pH of 12.5 and sets in the presence of moisture in approximately 4hrs^[4,5].

 

Perforation repair with MTA:^[15]

·       In the patient's 1^st visit, isolate the operating field with rubber dam, clean the perforation site; if there is bacterial contamination, medicate with calcium hydroxide for 1 week. Apply a 2-3 mm thick layer of MTA and take a radiograph to verify the correct positioning of MTA. Place a small wet cotton pellet in contact with MTA and place temporary restoration.

·       At the 2^nd visit after 24hrs, remove the temporary cement to check if MTA has set and complete the treatment.

·       In case of a perforation in the floor of the pulp chamber with the configuration of a cavity with 4 walls without any association with the root canal orifices, the perforation should be sealed with MTA before obturating the root canals.

·       In case of a strip perforation in the middle third of a root caused due to excessive enlargement of the root canal during cleaning and shaping, it is difficult to repair the perforation site with MTA before obturating without blocking the canal itself with MTA. The canal space apical to the perforation should be obturated first with gutta-percha and the perforation site should be sealed with MTA and the entire coronal portion of the root canal should be filled with MTA till the orifice.

 

CONCLUSION:

Mineral Trioxide Aggregate is a remarkable and desirable material in endodontics to treat root perforations. This is the best material till date which has an excellent prognosis compared to the other age old materials that were challenging in their ease of use to repair root perforations.

 

REFERENCES:

1.     Hariharavel VP, Ashok KA, Sankar A, Aravindhan R, Kavitha R. Repair of    perforation with Mineral trioxide aggregate (MTA). IOSR-JDMS. 2014;13(1):61-64.

2.     Byokod P, Shaikh S, Mota I, Aher U, Shah A. Nonsurgical Treatment of External Root Resorption and Furcal Perforation using MTA: A Magical Wand in Endodontics. Pravara Med Rev. 2014;6(1):29-33.

3.     Kakani AK, Veeramachaneni C, Majeti C, Tummala M, Khiyani L. A Review on Perforation Repair Materials. JCDR. 2015;9(9):9-13.

4.     Macwan C, Deshpande A. JORR. 2014;6(2):71-74.

5.     Unal GC, Maden M, Isidan T. Repair of Furcal Iatrogenic Perforation with Mineral Trioxide Aggregate:    Two Years Follow-up of Two Cases. Eur J Dent. 2010;4:475-481.

6.     Fuzz Z, Trope M. Root perforations: classification and treatment choices based on prognostic factors. Endod Dent Tranmatol. 1996;12:255-264.

7.     Torabinejad M, Hong CU, McDonald F, Pitt Ford TR. Physical and chemical properties of a new root-end filling material. J Endod. 1995;21:349-53.

8.     Kettering JD, Torabinejad M. Investigation of mutagenicity of mineral trioxide aggregate and other commonly used root-end filling materials. J Endod. 1995;21:537-42.

9.     Schwartz RS, Mauger M, Clement DJ, Walker WA 3 rd. Mineral trioxide aggregate: A new material for endodontics. J Am Dent Assoc. 1999;130:967-75.

10.  Nandini S, Ballal S, Kandaswamy D. Influence of glass Ionomer cement on the interface and setting reaction of mineral trioxide aggregate when used as a furcal repair material using laser Raman spectroscopic analysis. J Endod. 2007;33:167-72.

11.  Al-Hezaimi K, Al-Shalan TA, Naghshbandi J, Oglesby S, Simon JH, Rostein I. Antibacterial effect of two mineral trioxide aggregate (MTA) preparations against Enterococcus faecalis and Streptococcus sanguis in vitro. J Endod. 2006;32:1053-6.

12.  Torabinejad M, Hong CU, Lee SJ, Monsef M, Pitt Ford TR. Investigation of mineral trioxide aggregate for root-end-filling in dogs. J Endod. 1995;21:603-8.

13.  Budig CG, Eleazer PD. In vitro comparison of the setting of dry ProRoot MTA by moisture absorbed through the root. J Endod. 2008;34:172-4.

14.  Valois CR, Costa ED Jr. Influence of the thickness of mineral trioxide aggregate on sealing ability of root-end filling in vitro. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2004;97:108-11.

15.  Arnaldo C. The Use of Mineral Trioxide Aggregate to Repair Iatrogenic Perforations. Dentistry Today: Continuing Education. 2008; 105.2.

 

 

 

 

 

 

Accepted on 16.03.2017           © RJPT All right reserved