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RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES
KARNATAKA, BANGALORE
ANNEXURE II
PROFORMA FOR REGISTRATION OF SUBJECTS FOR
DISSERTATION
1.
Name of the candidate and
DR. VISHAL ANIL NALAWADE
address (in Block Letters)
DEPT. OF ORTHODONTICS AND
DENTOFACIAL ORTHOPAEDICS,
BANGALORE INSTITUTE OF DENTAL
SCIENCES AND HOSPITAL AND
POSTGRADUATE RESEARCH CENTRE,
5/3 HOSUR MAIN ROAD,
BANGALORE – 560029.
2.
Name of the Institution
BANGALORE INSTITUTE OF DENTAL
SCIENCES
AND
POSTGRADUATE
HOSPITAL
RESEARCH
AND
CENTRE,
BANGALORE – 560 029.
3.
Name of study and subject
MASTER OF DENTAL SURGERY IN
DEPARTMENT OF ORTHODONTICS AND
DENTOFACIAL ORTHOPAEDICS
4.
Date of Admission
2 MAY 2009
5.
Title of the Topic
The effect of sandblasting on the retention of
orthodontic bands - An in vitro study.
6.
BRIEF RESUME OF THE INTENDED WORK:
6.1 Need for the study:
Orthodontic band has been in clinical use for more than 100 years. Inspite of the wide
spread use of direct bonded brackets and tubes in clinical orthodontics, the conventional
band still plays an important role in fixed appliance therapy.
Although bonding of orthodontic tubes to the teeth is receiving much current interest in
the form of indirect bonding, the majority of buccal attachments are still being cemented
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using stainless steel bands and conventional cements, considering the force levels in the
posterior region.
The retention of orthodontic bands to the tooth surface is important to ensure fixed
appliance therapy. Numerous agents have been used to retain orthodontic bands. Zinc
phosphate cement was developed and introduced as a dental cement in 1878 and serves as a
standard with which relatively newer- Polycarboxylate (1968) & Glass ionomer (1971)
cements can be compared. Various surface treatments of bands are carried to improve the
retention. Sandblasting is one of them.
The purpose of the present in vitro study is to measure and compare the forces
required to deband orthodontic stainless steel bands with and without sandblasting while
using zinc phosphate, polycarboxylate and glass ionomer cements.
6.2 Review of Literature:
1. This study1 evaluated the effect of sandblasting in both laboratory and clinical trials.
The aim of the laboratory studies were to determine the effect of sandblasting on the
bond strength and survival time of orthodontic bands applied with Ketac-Cem
(Ketac-Cem, Espe, Gmbh, Seefeld/Oberbay, BRD).The amount of cement remaining
on the bands after debanding was also assessed. Clinically, the effect of sandblasting
on the failure rate of first molar orthodontic bands cemented with Ketac-Cem was
assessed. Survival time was assessed following simulated mechanical fatigue in a
ball mill. The effect of sandblasting on the failure rate of 320 first molar bands
cemented in 107 patients was examined in a half-mouth trial. In vitro, sandblasting
increased bond strength by 27% (P<0.01) and produced a three-fold increase in the
median survival time relative to the untreated sample (P<0.001) in the ball mill
experiment. Sandblasting resulted in more cement remaining on the band rather than
on the enamel after band removal. In vivo, sandblasting reduced the clinical failure
rate of the first molar bands (P<0.001).
2.
This study2 was done to evaluate efficacy of sandblasting of bands to increase the
bond strength. One hundred fifty extracted and cleaned bovine maxillary incisors
were collected. An apicoectomy was performed on each tooth, and the canal and
pulp chamber were cleaned out. Round, 6.35mm-diameter disks of stainless steel
band material were either left untreated or sandblasted with aluminium oxide. Fifteen
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untreated disks and 15 sandblasted disks were cemented by each of five methods.
1. Fuji II LC glass ionomer cement, 2. Ketac-cem radiopaque glass ionomer cement,
3. Blend-EZ zinc phosphate band cement, 4. Vitremer Tri-cure glass ionomer cement
(chemically cured), 5. Vitremer Tri-Cure glass ionomer cement (light cured). For
shear testing, the flat labial surface of each sample was aligned parallel to the testing
jig. Shear bond strengths were measured on an Instron 1350 universal testing
machine at a rate of 1mm/minute, and the debonding forces were recorded in
pounds. Each tooth and corresponding debonded disk were stored together for
assessment of the mode of bond failure under a stereomicroscope at 10X
magnification. Failures were scored according to the Adhesive Remnant Index (ARI)
of Artun and Bergland 6. The results strongly suggested that sandblasting the interior
surfaces of orthodontic bands provides a clear clinical advantage when combined
with glass ionomer cements. Shear bond strengths increase significantly, and
therefore the failure rate of the cemented bands should decrease.
3.
This in vitro study3 was conducted to evaluate the force required to cause debanding
when zinc phosphate, zinc polycarboxylate and glass ionomer cements are used as
the luting agents; and to determine whether sandblasting the inner surface of the
orthodontic bands affects the force required to deband. 20 extracted human
mandibular third molars with anatomy consistent with a mandibular first molar and
free of any sign of demineralization were selected. The teeth were embedded in
epoxy resin (special tray forming material, DeTrey) in plastic ice cube trays. The
exposed crowns were cleaned with a dental prophylactic paste (Zircate Prophy Paste,
LD Caulk) to remove any foreign debris. Stainless steel orthodontic bands (“A”
company, San Diego,Calif) with buccal attachments and lingual buttons were fitted,
seated and adapted to each molar. Each band was cemented in place with a
polycarboxylate cement (Poly-F Cement, DeTrey). Using an Instron testing machine
in tensile mode with a crosshead speed of 0.02 inch per minute, the force required to
deband the cemented bands was measured in kilograms and recorded in
megapascals. The debanded molar teeth were cleaned using a Schure scaler and
pumice to remove any remaining cement. The bands were cleaned in an ultrasonic
cleaner. The above procedures were repeated, using the same bands and the same
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teeth, with zinc phosphate(with fluoride, Ormco, Glendora, Calif) and glass ionomer
(Band Lok, Reliance Orthodontic Products, Itasca, III) cements. The whole
procedure was repeated with sandblasted bands. Glass ionomer cement demonstrated
the highest mean force value required to deband both the nonsandblasted and
sandblasted orthodontic bands. Sandblasting the inner surface of the bands proved to
be a useful method for increasing band retention for all three cements tested. The
mean force required to deband was approximately doubled following sandblasting.
4.
The aim of the study4 was to evaluate the effect of different roughening methods on
band retention. Three different types of cements were used in the study namely Zinc
Phosphate, Zinc Polycarboxylate and Glass Ionomer. 15 extracted human maxillary
first premolars were selected and were mounted upto cervical line in a block of self
curing acrylic. Five optimally sized, preformed stainless steel bands were selected
for each tooth. Buttons were welded to the buccal and lingual surfaces of each band.
The borders of the bands were marked for identification and were divided into five
groups. Group 1 band was used as control, Group 2 band was sandblasted with
50 micron aluminium oxide powder, Group 3 band was sandblasted with 90 micron
aluminium oxide, Group 4 band was surface roughened with a tungsten carbide bur
and Group 5 band was surface roughened with green stone. The bands were
subjected to tensile load testing using a Testometric Migro 500 Universal machine.
All four roughening methods demonstrated significantly greater retention than the
control group, but there were no statistically significant differences in retention
among the four roughening methods. Every roughened band failed at the cementenamel interface, leaving the cement adhering to the band. In the control group, the
cement remained on the enamel surface.
5. The aim of this prospective study5 was to compare the retention of micro-etched and
untreated first molar orthodontic bands in a randomized, half-mouth trial. Seventynine patients had 304 bands cemented as part of routine fixed appliance therapy. The
effect of micro-etching, patient age and gender, operator, molar crossbite, treatment
mechanics, and arch on band failure was investigated. Failure rates and survival
times were compared for each variable assessed. Micro-etched molar bands showed
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a significant reduction in clinical failure rate over untreated molar bands and an
increase in mean survival time (P<0.001). Of the other variables examined, only the
presence of a molar crossbite had any significant effect on band failure (P = 0.004).
6.3 Objectives of the study:
1. To compare the debanding force of orthodontic molar bands cemented using three
different luting cements.
2. Effect of in-office sandblasting procedure on the retention of orthodontic bands using
different cements.
3. To correlate the effectiveness of the procedure of sandblasting in a clinical situation
following the use of plain bands initially.
4. To evaluate the luting surface of the non-sandblasted and sandblasted bands using
scanning electron microscopy.
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MATERIALS AND METHODS:
7.1 Source of data:
30 extracted human mandibular third molars will be collected from Department of Oral
and Maxillofacial Surgery, BIDS, Bangalore. Dental cements Zinc Phosphate (Harvard),
Polycarboxylate (Densply), Glass Ionomer (GC Fuji) and 30 preformed Stainless steel
orthodontic bands (Ortho Organizers) will be used.
7.2 Methods of collection of data (including sampling procedures if any):

Part one
Nonsandblasted bandsThe sample will consist of 30 extracted mandibular third molars with anatomy
5
consistent with a mandibular first molar and free of demineralization. The collected
teeth will be embedded in epoxy resin in plastic ice cube trays. The exposed
crowns will be cleaned with dental prophylactic paste to remove debris.

Stainless steel orthodontic bands with buccal attachments and lingual buttons will
be fitted, seated and adapted to each molar.

Each band will be first cemented with polycarboxylate cement.

Using an Instron testing machine in tensile mode with crosshead speed of 0.02
inches per minute, the force required to deband the cemented bands will be
measured in kilograms and will be recorded in MPa (megapascals).

The debanded molar teeth will be cleaned using a ultrasonic scaler (Woodpecker)
and pumice to remove any remaining cement. The bands will be further cleaned by
placing in an ultrasonic cleaning tank for 20 minutes to facilitate removal of the
residual cement from inside the band.

The above procedures will be repeated, using the same bands and the same teeth,
with zinc phosphate cement and glass ionomer cement.

Part two
Sandblasted bands-

The second part of study will involve measuring the force required to deband when
the inside (luting) surface of the orthodontic band has been sandblasted.

For sandblasting, the luting surface of each band will be treated with aluminium
oxide powder (50 microns) particles directed from the sandblaster (Microetcher
ERC, Danville) under 80 psi of air pressure for 15 to 20 seconds, 24 hours prior to
the cementation procedure.

The procedure of cementation of bands with all the three types of cement and
debanding will be repeated in an identical manner as in the first part of the study.

One nonsandblasted stainless steel orthodontic band and one sandblasted band will
be photographed using a scanning electron electron microscope (SEM) directed at
the luting surface of the band. The photographs will be taken at 25 KV at a
magnification of 1000X.

The luting surface of each stainless steel orthodontic band will be calculated by
cutting the band with scissors and then measuring its length and width to the nearest
tenth of a millimeter using a Boley gauge. The force required to deband, will be
6
measured on the Instron machine, recorded in kilograms. The surface area and the
debanding force will be then used to calculate values of kilograms per square
centimeter for each tooth. Multiplying by a conversion factor of 0.0981 will give the
force required to deband in megapascals (MPa).
7.3 Does the study require any investigations or interventions to be conducted on
patients or other humans or animals? If so, please describe briefly.
Not applicable
7.4 Has ethical clearance been obtained from your institution in case of 7.3?
Not applicable
8.
LIST OF REFERENCES:
1) Millett D T, McCabe J F, Bennett T G, Carter N E, Gordon P H.
The effect of sandblasting on the retention of first molar orthodontic bands cemented with
glass ionomer cement.
Br J Orthod 1995;22:161-169.
2)Miller S, Zernik J H
Sandblasting of bands to increase bond strength.
J Clin Orthod 1996; 30: 217-222.
3) Wood D P, Paleczny G J, Johnson L N
The effect of sandblasting on the retention of orthodontic bands
The Angle Orthodontist 1996; 66:207-214.
4) Güray E, Karaman A I
Effects of different roughening methods on band retention.
J Clin Orthod. 1997;31:361-366.
5) Hodges S J, Gilthorpe M S, Hunt N P
The effect of micro-etching on the retention of orthodontic molar bands: a clinical trial.
Eur J Orthod 2001; 23:91-97.
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9.
Signature of Candidate
10.
Remarks of Guide
11.
Name and Designation of
(In block letters)
11.1 Guide
(Dr.Vishal Anil Nalawade)
This is a genuine study, which will be carried out by
the postgraduate student under my supervision and
guidance
Dr. Vinaya S.Pai
Professor and Head
Department of Orthodontics and
Dentofacial Orthopaedics,
Bangalore Institute Of Dental Sciences and
Hospital, Bangalore.
11.2 Signature
11.3 Co-Guide(if any)
Dr. Nandini S.
Professor
Department of Orthodontics and
Dentofacial Orthopaedics,
Bangalore Institute Of Dental Sciences and
Hospital, Bangalore.
11.4 Signature
11.5 Head of the Department
Dr. Vinaya S.Pai
Professor and Head
Department of Orthodontics and
Dentofacial Orthopaedics,
Bangalore Institute Of Dental Sciences and
Hospital, Bangalore.
11.6 Signature
12.
12.1 Remarks of the Chairman
and Principal
12.2 Signature
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