Rajiv Gandhi University of Health Sciences, Bangalore, Karnataka s18

Rajiv Gandhi University of Health Sciences, Bangalore, Karnataka Annuxere II Proforma for registration of subjects for dissertation

6) BRIEF RESUME OF THE INTENDED WORK

6.1 Need for the study

Successful endodontic therapy depends on thorough chemo mechanical 1) NAME OF THEpreparation CANDIDATE as well as three dimensional obturation that provides complete DR. DINESH.K sealing of the canals. AND ADDRESS #172,KEMPEGOWDA LAYOUT LAGGERRE GRAMA PEENYA POST BANGALORE-58 Alternating use of EDTA and Naocl has been time tested for its efficiency in

removing endodontic smear layer but lack sustained antimicrobial activity.

Due to its antimicrobial action and substantivity, chlorhexidine has been

suggested as an alternative irrigating solution that could replace Naocl .CHX is M.S. RAMAIAH DENTAL COLLEGE 2) NAME OFbactericidal THE INSTITUTION because of precipitation and/ or coagulation of intercellular AND HOSPITAL, BANGALORE. constituents.

Among the required physical properties of filling materials ,adhesion was found MASTER OF DENTAL SURGERY, 3) COURSEto OF be STUDYvery desirable AND property in root canal cements. DEPT OF CONSERVATIVE DENTISTRY AND SUBJECT ENDODONTICS.. Epoxy resin based sealer cements such as AH plus sealer has been widely used because of their acceptable physical properties ,reduced solubility, apical sealabality,microretention to root dentin, and adequate biological performance. 4) DATE OF ADMISSION TO THE 27-05-2009 COURSE In recent days adhesive dentistry has been introduced to field of endodontics with a specific focus on obtaining a ‘monobloc’ effect in core material, sealing agent, and the root canal dentin which forms a single cohesive unit. ‘ ‘ The Effect of 2% Chlorhexidine on the 5) TITLE OF THE TOPIC Bond strength of two different root canal Activ-Gp is a new glass ionomer impregnatedfilling systems’’- and coated an gutta-percha EX VIVO cones STUDY that are bonded to a sealing agent this was claimed to offer adhesive bonding of core material to intraradicular dentin via the glass ionomer sealer. Few studies have investigated the degree of bonding and adaptation of this material to root canal dentin. but to date very few literatures have determined effect of 2%CHX on the sealer – dentin bond strength when using Activ –GP obturation system

1 Hence, this study aims at comparing the bond strength of Activ –GP root canal obturation system and gutta-percha/AH plus sealer following 2%CHX as a final irrigant regimen.

6.2 Review of literature

In a study on clinical efficiency of 2% chlorhexidine gel in reducing intracanal bacteria showed that 2% chlorhexidine gel is an effective root canal disinfectant, and additional intracanal dressing with ca(oH)2 did not significantly improve the disinfection.

In a study by Ahmed et al , “Effect of different irrigating solutions on bond strength of two root canal-filling systems” in which EDTA, CHX and MTAD were used as an final irrigant concluded that bond strength of Activ-GP can be improved by final irrigation with 17%EDTA followed by 2%CHX and CHX does not enhance the effect of MTAD on Activ-GP bond strength.

In a study, Comparative assessment of Activ – GP/Glass ionomer sealer, Resilon /epiphany, and Guttapercha/AH plus obturation: A bacterial leakage study it was concluded that the single cone Activ GP/GI sealer system has potential as an obturation system provide a seal comparable that achieved with other popular obturation systems.

In a study done on in vitro comparisons of bond strength of various obturation materials to root canal dentin using a push out test design concludes that roots filled with gutta-percha and AH plus sealer had significantly( p<0.05) higher bond strength compare with all other groups.

Another study on efficacy of two contemporary single cone filling techniques in preventing bacterial leakage concluded that gutta-percha and AH plus sealer appears to be more effective in minimizing bacterial leakage in comparision with Activ-Gp and Gutta flow.

MATERIALS AND METHODS USED

7.1 MATERIALS USED

 Twenty four single rooted teeth.  2% CHX  Guttapercha , AH plus Sealer(Dentsply)  Activ- GP (Brasseler USA)  Stereo microscope  Universal testing machine .

2 7.2 METHODOLOGY

Twenty four extracted human single rooted teeth will be decoronated to obtain approximately 16mm long root segments. ↓ Root canal instrumented using k3 0.06 taper niti rotary instruments or to size #40 kfile, enlarge to working length irrigation with 3ml Naocl performed with each file size. ↓ According to final irrigation regime

Roots will be randomly divided into two groups (n=12) Group 1 :- 5ml of 17% EDTA Group 2 :- 5ml of 17% EDTA followed by 5ml 2% CHX ↓ Based on the obturation system

Each groups are further sub divided into two sub groups (n=6) Sub group A :- Guttapercha + AH plus sealer Sub group B :- Activ – GP + glass ionomer sealer

Sub group A

Master cone will be selected and Canal filled with warm Guttapercha and AH plus sealer, plugger will be used to condense master cone within 5mm from working length. Coronal and middle third will be back filled using thermo plasticized technique.

Sub group B

Activ GP coated with GIC sealer will be inserted into canal up to working length. surplus of cone will be removed by using hot system B plugger and sealer will be placed on the top .

Roots will be embedded in epoxy resin and three horizontal sections of 2mm thickness made from coronal , middle third and apical portion of each root this will result in -18 horizontal sections per subgroup. -72 horizontal sections for four experimental subgroups.

Sections will be coded and measured for apical and coronal diameter of the obturated area using stereomicroscope.

Each section will then be subjected to a compressive load via universal testing machine at a cross head speed of 1mm/min using plunger placed such that it only contacts the filling material. 3 Push out force applied in apicocoronal direction until bond failure occurs which will be manifested by sudden drop along load deflection.

Maximum failure load will be recorded in Newton’s and calculated according to following formula.

Push-out bond strength(MPA) = Maximum load (n) Adhesion area of the root canal filling (mm)2

Adhesion surface area calculated as. (∏ r1 + ∏ r2) * L

L=√(r1-r2)2 + h2

∏ is a constant = 3.14 r1 : - Smaller radius r2 : - longer radius h : - thickness of section in mm.

STATISTICAL ANALYSIS :

Data will be presented as mean and standard deviation values. A regression model with two –way analysis of variance will be used in testing significance for the effect of material and irrigant and their interactions on mean push out bond strength. A Tukey post hoc test will be used for pair-wise comparison between the means. The significance level will be set at p< 0.05

4 7.3 Does the study requires any investigations or intervention to be conducted on

patients or other humans or animals?

7.4 Has the ethical clearance been obtained from your institution in case of

the above?

NOT APPLICABLE

5 REFERENCES

1. Cbing s.wang, Roland R. Arnold, Martin Trope, Fabricio B.Teixeria Clinical Efficiency of 2% chlorhexidine gel in reducing intracanal bacteria Journal of Endodontics 2007; 33: 1283-9

2. Ahmed Abdel Rahman Hashem, * Angie G. Ghoneim, † Reem A. Lutfy, and Manar Y. Fouda, The Effect of different irrigating solutions on bond strength of two root canal-filling systems. Journal of Endodontics 2009; 35-4: 537-40

3. Joel N. Fransen, Jaining He, Gerald N. Glickman, Alejandro Rios etal. Comparative assessment of Activ – GP/Glass ionomer sealer, Resilon /epiphany, and Guttapercha/AH plus obturation : a bacterial leakage study Journal of Endodontics 2008; 34: 725-7

4. Matthew A Fischer, David W. Berzins, JamesK. Bahcall. An in vitro comparisons of bond strength of various obturation materials to root canal dentin using a push out test design Journal of Endodontics 2007; 33: 856-8

5. Francesca Monticelli, Fernanda T. Sadek , George S. Schuster, Keith R. Volkmann etal. Efficacy of two contemporary single cone filling techniques in preventing bacterial leakage Journal of Endodontics 2007; 33: 310-3

6 7 12) REMARKS OF THE ETHICAL

COMMITTEE CHAIRMAN AND

PRINCIPAL

SIGNATURE