Materials And Method - Shodhganga : a reservoir of …shodhganga.inflibnet.ac.in/bitstream/10603/94487/5/4... · Web viewEquipments & Materials used in the study Specimen cleaning

Materials And Method

The present in vitro study was conducted in the Subharti

University, Meerut and Research lab of Cimec Technologies Pvt.

Ltd., Anand Industrial Estate, Mohan Nagar, Ghaziabad, India. The

purpose of this study was to evaluate the fracture resistance of

samples with the relative loss of PCD followed by the use of

intraradicular & intracoronal restoration and reinforcement

material.

Equipments & Materials used in the study

Specimen cleaning & storage:

1) Ultrasonic scaler (Woodpecker DTE D5, China).

2) 1% Chloramine-T (Hi Media Labs, India).

Specimen preparation:

1) Round Bur BR-45 ISO 001/010 ; straight bur ISO

109/013, SF-31, Mani Inc. Kiyohara Industrial Park, Tochigi,

Japan.

2) Air rotor handpiece (NSK, Japan)

3) Straight handpiece and motor (Marathon, India)

Page 85


4) Endo Access Bur (Dentsply, Mallifer Ballaigus,

Switzerland)

5) Normal Saline (Nirlite, India).

6) Digital vernier calliper. (SPAC Systems, Japan).

7) Glass slab

Endodontic shaping & cleaning:

1) EndoBloc (Dentsply, Mallifer Ballaigus, Switzerland).

2) K- files of size #10 - #30 : 21mm and 25mm (Dentsply

Malliefer, Ballaigues, Switzerland).

3) Protaper rotary system files (Dentsply Malliefer,

Ballaigues, Switzerland)

4) Endodontic Torque Control Motor: X Smart (Dentsply,

Mallifer, Ballaigues Switzerland).

5) RC-Prep lubricant (Premier Dental Products, Tulsa, UK).

6) 5.25 % Sodium hypochlorite (Amble healthcare pvt. ltd.,

New Delhi)

7) Distilled Water (B.K. chemicals, India).

8) 30 gauge 1, 2ml and 5ml Syringe (Dispovan, India).

9) Avue prep liquid EDTA (Dental Avenue, India)

Page 86


Obturation:

1) Paper Points (Dentsply Malliefer, Ballaigues, Switzerland).

2) Lentulospiral (Dentsply Malliefer, Ballaigues, Switzerland).

3) Protaper Cones (Dentsply Malliefer, Ballaigues, Switzerland)

4) AH plus resin Sealer (Dentsply Malliefer, Ballaigues,

Switzerland).

Intracoronal restorative materials:

1) Nanofilled Resin Modified Glass Ionomer Cement- Nano-

ionomer Ketac N100 (3M/ESPE, St Paul, MN,USA).

2) Temporary cement (MD Temp,Meta Biomed,USA).

Instruments used for intracoronal restoration

1) Agate spatula (API, Ashoosons Dental Equipments.India)

2) Mixing pad (3M/ESPE, St Paul, MN, USA)

3) Teflon coated Composite instruments (Hu-Friedy, Germany)

4) Pro-matrix disposable band and retainers (Astek

innovations, UK)

Mounting of specimens:

1) Self curing acrylic (Rapid repair, Ashvin, Mumbai, India).

2) Stainless steel blocks (Tianjin haiqianwei pipe co. ltd, India).

3) Elastomeric Impression material (Aquasil, 3M, USA)

Page 87


Equipments:

1) Stereomicroscope (Alco, India)

2) Light curing unit (Unicorn, India)

3) Incubator (Weiss Gallenkam, Germany)

4) Universal testing machine (Micronix, Korea) with stainless

steel fixtures and hardened steel chisel.

5) Thermocycling apparatus (custom made)

Methodology

Sample Preparation:

A total of one hundred ninety extracted human mandibular molar

teeth with two roots were selected after approval from ethical

committee and used for this study (Fig.11).In order to standardize,

anatomic crowns with similar dimensions (11±1 mm mesiodistal

and 10±1 mm buccolingual diameters) were measured with a

digital caliper (Fig. 2).

Soft tissue deposits and calculus were removed with an

ultrasonic scaler. Teeth were stored in 1% chloramine-T solution

for 12 hours and transferred to distilled water until use (Fig. 10).

Page 88


Exclusion Criteria

• Single root and Multiple roots (more than two).

• Previous root canal treatment.

• Roots with abrupt canal curvatures.

All the teeth were examined under a stereomicroscope at 10 X

magnification to ensure the absence of pre-existing cracks or

fractures (Fig. 3). Crowns were resected so that a final dimension

of 4 mm measured from one mm below highest point of proximal

cervical line is achieved (Fig. 13). Then, the depth grooves were

prepared in the enamel and it was carefully removed with a

diamond abrasive point from all the surfaces (Fig. 14, 15).The

samples were examined under a stereomicroscope to ensure

complete removal of enamel.

Endodontic access preparation:

Endodontic access cavities were prepared with round bur # 2 and

Endo access bur used in a high speed handpiece under constant

water cooling. The access was prepared in accordance with the

dimensions of the pulp chamber and straight line access was

ensured (Fig. 16). The Samples for control group were prepared till

Page 89


this step with no biomechanical preparation of root canal .Only the

debris was removed from the pulp chamber and the canal with

copious saline irrigation. The patency was checked with 15 K- file

with no preparation of root canal at all. Rest all the samples

followed the procedure described below.

The patency was checked with 15 K- file .The working length was

determined by placing a 15 K- file into the canal until it was just

seen at the apical foramen and then 1mm was subtracted from this

length.

Shaping and cleaning of root canal system:

Root canal therapy was carried out following standardized

procedure for all the samples. A size 15 K- file was used to

negotiate the root canal. Mesial and distal root canals were then

instrumented with Rotary ProTaper in a sequential manner till F3

using crown down technique in accordance with manufacturer’s

recommendation for torque, speed and sequence of files. During

the procedure, patency and glide path verification was done with

size 10 K- file.2 ml of 5.25% sodium hypochlorite was used to

irrigate the prepared canals after every instrumentation. The root

Page 90


canals received a final irrigation of 5 ml 17% EDTA, after which the

canals were flushed with 10 ml distilled water to avoid the

prolonged effect of EDTA. Root canals so prepared were dried

with protaper paper points.

Root Canal Obturation:

Root canal preparation was judged to be complete when tug-back

was achieved with a corresponding protaper guttapercha point at

working length. The cleaned and shaped canals were then dried

with paper points before obturation. Obturation of the prepared

root canals was done with the Protaper universal gutta percha

points using single cone technique and AH Plus sealer .The

manipulation of sealer was done in accordance with the

manufacturer’s instructions. The root canals were coated with

sealer using lentulospiral. The cones were also coated with sealer

and placed in the canal at the predetermined working length. The

extra Gutta Percha protruding out of the orifices was seared off

with a heated instrument and the chamber was cleaned off the

excess sealer. The samples at this stage were left in the incubator

(Fig. 5) for 24 hrs to ensure complete setting of the sealer (Fig.

17).

Page 91


Table 1: Composition of materials used for intraradicular and

intracoronal reinforcement

Materials Used Composition

Protaper Gutta Percha Cones (Fig 6)

Gutta Percha ,wax/resin, zinc oxide,barium

sulfate

AH Plus Sealer (Fig 7)

Paste A: Bisphenol-A epoxy resin, Bisphenol-

F epoxy resin, calcium tungstate, zirconium

oxide, silica and iron oxide pigments. Paste

B: Dibenzydiamine, aminoadamante,

trycyclodecane- diamine, calcium tungstate,

zirconium oxide, silica and silicone oil.

Ketac N 100 (Nano- filled RMGIC/Nano-ionomer) (Fig 8)

HEMA (hydroxyethylmethacrylate) or BIS-

GMA (bisphenol-glycidylmethacrylate)

fluoroaluminosilicate glass together with

silica/zirconia nanofillers (5.25nm) and

nanoclusters (1.0-1.6µm) – 69% by weight

Temporary cement (MD Temp) (Fig 9)

Zinc Oxide, Zinc sulphate, Poly vinyl acetate

copolymer, Ethanol.

Thereafter, gutta percha was removed from the intraradicular

space with a heated periodontal probe followed by a small round

bur so that the final depth of preparation was 8 mm as measured

Page 92


from the occlusal end of the sample (Fig.18,19).The debris was

cleared from the intraorifice preparation and intracoronal space.

Quantification of PCD and standardisation of sample

distribution for groups:

All the specimens treated endodontically in this project will be

included for quantification. A customised apparatus was fabricated

using a glass slab and a syringe (Fig. 20). A 2 ml plastic syringe

was cut into a cylinder of 8 mm height and ends of the cylinder

were smoothened with a 100 grit sand paper. One end of the cut

cylinder was pasted on the surface of the glass slab with

cyanoacrylate (Fig. 21,22). The cylinder was filled with water with a

1 ml syringe with a least count of 0.01ml. The volume of that

cylinder was measured and noted (X) (Fig.23).Then, the pulp

chamber of the samples and intraradicular space was filled with

water and volume was noted (Y) (Fig. 24). Thereafter, the sample

was inverted, inserted and placed in the cylinder (Fig.25).The

remaining space in the cylinder was filled with water and measured

(Z) (Fig. 26).

Volume of PCD = X – (Y+Z)

Page 93


The values so obtained will be noted and then the samples were

divided amongst groups in such a manner that all the groups got

samples with equally distributed highest, lowest and average

values of PCD. This distribution helped to standardise samples

within groups.

Sample preparation, Intraradicular and intracoronal

reinforcement of PCD:

Control group : The pulp chamber exposed due to access

preparation will be filled with temporary cement after cleaning

debris in the pulp chamber with saline (Fig. 27).

Research group 1: The pulp chamber and introrifice space of

endodontically treated samples as mentioned in sample

preparation will be filled with temporary cement (Fig. 28).

Research group 2: The pulp chamber and introrifice space of

endodontically treated samples as mentioned in sample

preparation filled with nano-ionomer (Fig. 28).

Research Group 3: The mesial wall of endodontically treated

samples will be removed in standardized manner (3 mm width and

3 mm height as measured from the mesial ridge of PCD) with a Page 94


straight bur. The intracoronal and intraradicular space of samples

will be restored with temporary cement after cleaning debris with

saline (Fig. 29).

Research Group 4: The mesial wall of endodontically treated


3 mm height as measured from the mesial ridge of PCD) with a


will be restored with nano-ionomer after cleaning debris with saline

(Fig. 29).

Research Group 5: The distal wall of endodontically treated


3 mm height as measured from the distal ridge of PCD) with a



(Fig. 29b).

Research Group 6: The distal wall of endodontically treated


3 mm height as measured from the distal ridge of PCD) with a


Page 95



(Fig. 29b).

Research Group 7: The buccal wall of endodontically treated


3 mm height as measured from the buccal ridge of PCD) with a

straight bur . The intracoronal and intraradicular space of samples

will be restored with temporary cement after cleaning debris with

saline (Fig. 30).

Research Group 8: The buccal wall of endodontically treated


3 mm height as measured from the buccal ridge of PCD) with a



(Fig. 30).

Research Group 9: The lingual wall of endodontically treated


3 mm height as measured from the lingual ridge of PCD) with a


Page 96



(Fig. 31).

Research Group 10: The lingual wall of endodontically treated


3 mm height as measured from the lingual ridge of PCD) with a



(Fig. 31).

.Research.Group 11: 1mm of uniform tooth structure will be

removed all around the endodontically treated samples and after

that the pulp chamber and introrifice space of samples will be

restored with Temporary cement after cleaning debris with saline

(Fig. 32).

Research Group 12: 1mm of uniform tooth structure will be

removed all around the endodontically treated samples and after

that the pulp chamber and introrifice space of samples will be

restored with nano-ionomer after cleaning debris with saline (Fig.

32).

Page 97



removed from the inside mesial access wall of the endodontically

treated samples and after that the intracoronal and intraradicular

space of samples will be restored with Temporary cement after

cleaning debris with saline (Fig. 33).

Research Group 14 : 1mm of uniform tooth structure will be

removed from the inside mesial wall of the endodontically treated

samples and after that that the intracoronal and intraradicular

space of samples restored with nano-ionomer after cleaning debris

with saline (Fig. 33).


removed from the inside distal wall of the endodontically treated

samples and after that the pulp chamber and introrifice space of

samples restored with Temporary cement after cleaning debris



removed from the inside distal wall of the endodontically treated

samples and after that the that the intracoronal and intraradicular

Page 98


space of samples restored with nano-ionomer after cleaning debris



removed from the inside mesial and distal wall of the

endodontically treated samples and after that the intracoronal and

intraradicular space of samples will be restored with Temporary

cement after cleaning debris with saline (Fig. 35).


removed from the inside mesial and distal wall of the

endodontically treated samples and after that that the intracoronal

and intraradicular space of samples will be restored with

nanoionomer after cleaning debris with saline (Fig. 35).

Intra-radicular Obturation and Intra-coronal (8mm)

Restoration

Primer was applied using applicator tip to the entire surface and

massaged over the entire area for 15 seconds. A gentle stream of

air was used to spread primer into a thin even film.

Page 99


It was cured for 10 sec. A cement spatula was used to mix the

pastes for 20 sec until a uniform color was achieved and the

Page 100


Table 2: Intra-radicular Obturation and Intra-coronal (8 mm)

Restorations in different groups

Control Group and Research GroupsIntracoronal and intraradicular (8mm) Restoration

Control Group (No root canal treatment) Temporary cement

Research Group 1 (RCT and Intact sample) Temporary cement

Research Group 2 (RCT and Intact sample) Nano-ionomer

Research Group 3(mesial wall of access preparation removed)

Temporary cement

Research Group 4(mesial wall of access preparation removed)

Nano-ionomer

Research Group 5(distal wall of access preparation removed) Temporary cement

Research Group 6(distal wall of access preparation removed) Nano-ionomer

Research Group 7(buccal wall of access preparation removed)

Temporary cement

Research Group 8(buccal wall of access preparation removed)

Nano-ionomer

Research Group 9(lingual wall of access preparation removed)

Temporary cement

Research Group 10 (lingual wall of access preparation removed)

Nano-ionomer

Research Group 11(1mm all around tooth structure removed) Temporary cement

Research Group 12 (1mm all around tooth structure removed)

Nano-ionomer

Research Group 13 (1mm inside mesial wall removed) Temporary cement

Research Group 14 (1mm inside mesial wall removed) Nano-ionomer

Research Group 15 (1mm inside distal wall removed) Temporary cement

Research Group16 (1mm distal wall removed) Nano-ionomer

Research Group 17(1mm mesial and distal wall removed) Temporary cement

Research group 18 (1mm mesial and distal wall removed) Nano-ionomer

Page 101


preparation was restored incrementally in a depth of 2 mm in

intraradicular space followed by intracoronal space in further

increments of 2 mm each. Each increment was light cured as per

manufacturer’s recommendations. Each increment was cured for

20 sec by holding the light tip guide as close as possible to the

sample. For samples with missing walls, Pro-matrix (Astek

innovations, UK) matrix band and retainer system was used.

Thermocycling of samples

The thermocycling of samples was done in a customised

apparatus (Fig..38, 40) The ISO TR 11450 recommended protocol

of 500 cycles in water between 5 and 55 degrees C with a dwell

time of 20 secs. and transfer time of 5 secs was used (Fig..39).

Simulation of Periodontal ligament & Mounting of samples

before testing:

The root surfaces of samples were dipped into melted modeling

wax in a wax bath to a depth of 1 mm below the CEJ to produce a

thin, uniform layer (Fig 41).Thereafter, each tooth was aligned

vertically along their long axis in self-curing acrylic resin (Quick

Ashvin, India) filled in 15 x 15 x 25 mm dimension (length x

breadth x height) stainless steel blocks at a level 1mm apical to

Page 102


cement-enamel junction (Fig 42). After polymerization, each tooth

was removed from the block (Fig 43). The wax spacer was

removed from the root surface and the simulated alveolus of

acrylic resin blocks (Fig 44).Light bodied Vinyl Polysiloxane

elastomeric impression material was delivered into acrylic resin

blocks and the tooth was reinserted into alveolus and the material

was allowed to set (Fig 45). Excess polysiloxane material was

removed with a scalpel blade (Fig 46, 47).

Testing of samples for fracture in universal testing machine:

Thereafter, the samples were mounted on a universal testing

machine and fastened with the help of clamps which was fixed to

lower arm of universal testing machine (Fig 49, 50). A custom

stainless steel loading fixture screwed to the top of machine and

with a 4 mm spherical tip was centered(Fig. 51). A compressive

force at a crosshead speed of 1 mm/min was applied to the

occlusal surface of the sample until the fracture occurred.

The force required to fracture each sample was recorded in

Newton (N). The data so obtained was tabulated and statistically

analysis was done.

Page 103

Documents

Materials And Method - Shodhganga : a reservoir of …shodhganga.inflibnet.ac.in/bitstream/10603/94487/5/4... · Web viewEquipments & Materials used in the study Specimen cleaning