56 Journal of the College of Physicians and Surgeons Pakistan 2014, Vol. 24 (1): 56-59

INTRODUCTIONIt has been observed that about 20 – 30% of 12 yearsold children have suffered some form of dental injuries.1

When teeth with incomplete root formation suffer pulpnecrosis, the formation of dentine stops, and rootdevelopment ceases. Consequently, the canal remainslarge, with thin and fragile walls, and the apex remainsopen. These features make instrumentation of thecanal difficult and hinder the formation of an adequateapical stop.

There are different treatment options such as apexi-fication technique using calcium hydroxide, one-visitMTA apical plug apexification, retrograde filling, revas-cularization to induce the root closure if the patient is ingrowing age.

Calcium hydroxide pastes have become the material ofchoice in these cases to induce apexification.2 However,the apexification procedure may take many months andrequire multiple visits, making patient compliance aproblem. It may also further weaken the teeth andpossibility of increased tooth fracture after the use ofcalcium hydroxide for extended periods.3

For these reasons one visit apexification has beensuggested.2 Mineral trioxide aggregate (MTA) has beenproposed as a material suitable for one visit apexi-

fication.4 However, there is a little published informationabout its use in cases of immature teeth with openapices in humans. Previous reports of MTA in root-end-closure are primarily case reports only.4,5

The monoblock obturation technique or filling of theentire root canal system with MTA is the logicalprogression in the evolutionary application of thismaterial for non-vital immature teeth. The monoblockscreated in the root canal spaces are classified asprimary, secondary or tertiary type.6 According to thisclassification, mineral trioxide aggregate monoblockobturation represents a contemporary version of theprimary monoblock.

Mineral trioxide aggregate (MTA) might have a profoundadvantage when used as canal obturation materialbecause of its superior physiochemical and bioactiveproperties MTA provides an effective seal againstdentin.7 MTA obturation in teeth with immature apicescan induce apexogenesis by stimulating the mesen-chymal stem cells from the apical papilla to promotecomplete root maturation in the presence of periapicalpathosis and abscesses.8 Recent data have demons-trated that root canal treated teeth obturated with MTAexhibit higher fracture resistance than their untreatedcounterparts.9 Previously only few case reports of MTAmonoblock obturation technique in non-vital immaturepermanent teeth have been documented.10,11

The aim of this report was to present the short-termfollow-up results in ten consecutively treated permanentmaxillary incisors that presented with non-vital pulps,open root apices and, were treated by mineral trioxideaggregate (MTA) monoblock obturation technique.

METHODOLOGYThis report include ten permanent maxillary incisorsin 10 subjects aged between 13 and 32 years who

EVIDENCE BASED REPORT

Monoblock Obturation Technique for Non-Vital Immature PermanentMaxillary Incisors Using Mineral Trioxide Aggregate:

Results from Case SeriesZahid Iqbal1 and Abdul Hakeem Qureshi2

ABSTRACTTen patients presented with non-vital immature teeth for root canal treatment. In all these cases the pre-operative clinicalexamination revealed apical periodontitis with a buccal sinus tract of endodontic origin. These cases were treated by amineral trioxide aggregate (MTA) monoblock obturation technique. Follow-up evaluations were performed at 1 – 2 yearsafter treatment. Eight out of 10 cases were associated with periradicular healing at follow-up evaluation. Mineral trioxideaggregate Monoblock obturation technique appears to be a valid material to obtain periradicular healing in teeth with openapices and necrotic pulps.

Key Words: Mineral trioxide aggregate. Necrotic pulp. Monoblock obturation.

1 Department of Operative Dentistry and Endodontics, College of Dentistry/Qassim University, Kingdom of Saudi Arabia.

2 Department of Operative Dentistry and Endodontics, Collegeof Dentistry / Ziauddin University, Karachi.

Correspondence: Dr. Zahid Iqbal, Assistant Professor,Flat-705, Humma Heights, 133 Depot Line, M. A. Jinnah Road,Karachi.E-mail: zahidig@hotmail.com

Received: February 07, 2013; Accepted: August 30, 2013.

presented with non-vital immature permanent teeth forroot canal treatment at the Department of Endodonticsof the College of Dentistry of the Ziauddin University,Karachi, Pakistan, from January 2010 to January 2012.The inclusion criteria were patients presenting withincomplete development of the involved tooth withoutany root fracture or internal or external resorption ofthe tooth.

Clinical and radiographic examination were performedand clinical diagnosis were made (Table I). Ethicalapproval was sought and granted. Informed consentwas obtained from all the subjects.

The teeth were isolated with a rubber dam. A conven-tional access cavity was prepared and the canal wasthen gently cleaned with manual instruments and5% NaOCl irrigation (Clorox, Pakistan). The workinglength was measured radiographically with a K-file andrecorded for reference (Table I).

The canals were dried with sterile paper points and filledwith calcium hydroxide (Ultracalx Ultradent, USA)placed using intracanal capillary tips (Ultradent Inc.),and the access cavity was sealed with cavit (3M ESPE,Asia). After one week, the calcium hydroxide wasremoved by rinsing with alternating solutions of NaOCl5% and EDTA 17% (META). A final rinse with sterilewater was performed. Once the canal was dry at theworking length, with no exudates, the full canal was filledwith MTA (Dentsply Tulsa). Table I outlines the numberof calcium hydroxide medications, and the time neededto obtain a dry canal.

Mineral trioxide aggregate were mixed, as recom-mended by the manufacturer, and filled the whole canalusing hand Lawaty technique.11 The armentarium usedfor MTA placement and adaptation were containingamalgam gun and locally modified hand and fingerpluggers, K-file with flat end (Figure 1).

MTA was mixed in a dappen dish and transferred to thepulpal floor with amalgam gun. An apex locator was thenattached to a K-file, 1 size smaller than the MAF. TheK-file was moved circumferentially along the canalglide path with an apical pumping motion by using the

coronal portion of the canalas a funnel, which allowsthe MTA to flow from theaccess cavity reservoir tothe canal terminus. Theapex locator was removedas the depth of the canalglide path was reduced,and the apical MTA plugwas formed. The MTA can,thereafter, be circumferen-tially funneled and pumped.A sterile sponge pelletmoistened with sterilewater was placed over thecanal orifice and the access

cavity was sealed temporarily. Correct placement ofMTA was confirmed radiographically. At the nextappointment, the access cavity was sealed and theteeth were restored with dentine and enamel-bondedcomposite.

Cases were reviewed radiographically using theparalleling technique at the first visit, and at the 12 and24 months follow-up appointments. Clinically, treatmentwas considered successful when symptoms such aspain, swelling, buccal sinus tract, or tenderness to apicaland gingival palpation or percussion were absent.

Healing was classified according to the radiographicappearance against the following criteria: (i) completehealing: complete regeneration of the periodontalligament space; (ii) partial complete healing: substantialreduction (more than 75%) in the diameter of periapicallesion; (iii) incomplete healing: substantial reduction(more than 50%) in the diameter of the periapical lesion;and (iv) unsatisfactory healing: no reduction or anincrease in the diameter of the periapical lesion.

RESULTSAt the 12-month clinical examination, all teeth were freefrom symptoms, buccal sinus tracts, and swelling.Radiographic examination revealed incomplete reso-lution of the periapical lesion in all cases (Figure 2Cand 3C).

Monoblock obturation technique for non-vital immature permanent maxillary incisors using mineral trioxide aggregate

Table I: Descriptive data at the first visit, working length and time needed before mineral trioxide aggregate (MTA) monoblock obturation.

Patient number Gender Tooth Age of patient Working length Number of intracanal Number of days (years) (mm) medication with for intracanal

calcium hydroxide medication

1 F 11 15 18 1 7

2 M 21 28 20 2 14

3 M 11 14 21 1 7

4 M 21 29 22 2 14

5 F 11 13 17 1 7

6 F 21 14 20 1 7

7 F 21 19 23 2 14

8 F 21 16 22.5 1 7

9 M 11 32 21 1 7

10 F 21 15 23 1 7

Figure 1: Locally modified handand finger pluggers, K-file with flatend.

Journal of the College of Physicians and Surgeons Pakistan 2014, Vol. 24 (1): 56-59 57

At the 24-month follow-up, 8 teeth displayed partialcomplete healing (Figure 2D and 3D). In two teeth(patient no. 4 and 6), although the clinical symptomsdisappeared and the tooth was in adequate clinicalfunction, the radiographic follow-up revealed incompletehealing with substantial reduction (more than 50%) inthe size of the periapical lesion (Figure 4B and 4D).

DISCUSSIONIn general, the outcomes in this case series are nearlysimilar to previously reported cases of successful MTAmonoblock obturation technique in teeth with necroticpulps and open apices.10,11 The previous reports confirmthat MTA can be considered as an effective material tosupport regeneration of apical tissues in immaturenecrotic teeth. The treated teeth were asymptomatic,and radiographic follow-ups showed healing of peri-radicular tissues and new hard tissue formation in theapical area of the affected teeth. For the present study,a 2-year follow-up evaluation revealed partial completehealing in 8 out of 10 cases. In all these cases, the pre-operative clinical examination revealed apical perio-dontitis with a buccal sinus tract of endodontic origin.

At the 2-year follow-up examination, 2 cases (patient no.4 and 6) displayed incomplete healing. For thesepatients, the pre-operative radiolucency was extensive,and involved teeth presented with wide-open apex.These two teeth with incomplete healing at the 2-yearradiographic follow-up also revealed substantialreduction (more than 50%) in the size of the periapicallesion. It can be assumed that the very large pre-operative apical lesion and wide-open apex would needa longer period of time to heal.

It was also observed that all treated teeth obturated withMTA were not fractured at the 2-year follow-upexamination and this outcome is similar to recentresearch on immature tooth models that were obturatedwith MTA and indicated that MTA showed higher fractureresistance than untreated controls.9

The canal obturation with MTA requires the samepreparation and irrigation normally executed for gutta-percha placement. The placement of the MTA can beaccomplished using different methods. MTA can beplaced by using ultrasonic energy or hand condensationtechnique with or without the help of microscopic vision.In the present study, the MTA were placed by astandardized hand condensation Lawaty technique.

Based on our observations, the non-surgical manage-ment of teeth with necrotic pulps and incomplete apexformation with MTA monoblock obturation was success-ful. In two out of 10 cases, the radiographic healing wasincomplete, a finding which may have been influencedby the initial severity of the lesion and the architecture ofthe root-end or both these factors contributing togetherfor incomplete healing.

CONCLUSIONOrthograde MTA monoblock obturation placed by handcondensation technique resulted in a successful out-come for a period of 2-year. Mineral trioxide aggregatemonoblock obturation technique appears to be a validmaterial to obtain periradicular healing in teeth with openapices and necrotic pulps.

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Zahid Iqbal and Abdul Hakeem Qureshi

58 Journal of the College of Physicians and Surgeons Pakistan 2014, Vol. 24 (1): 56-59

Figure 2 (A,B,C,D): (A) Pretreatment radiograph (B) Working lengthradiograph (C) Incomplete healing at 1 year follow-up (D) Partial completehealing at 2-year follow-up.

Figure 3 (A,B,C,D): (A) Pretreatment radiograph (B) Working lengthradiograph (C) Incomplete healing at 1 year follow-up (D) Partial completehealing at 2-year follow-up.

Figure 4 (A,B,C,D): (A) Pretreatment radiograph (B) Incomplete healing at2-year follow-up (C) Pretreatment radiograph (D) Incomplete healing at2-year follow-up.

Monoblock obturation technique for non-vital immature permanent maxillary incisors using mineral trioxide aggregate

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