Indirect bonding involves placing orthodontic brackets onto dental models or casts in the lab, then transferring them to the patient's teeth using transfer trays. There are several methods for indirect bonding, including the Thomas method using double sealant technique, Knights method bonding brackets directly to casts, and Sondhi's method using Bioplast trays. Indirect bonding provides more accurate bracket placement compared to direct bonding but requires extra lab time and carries risks of adhesive flash or bracket loss during transfer.

1. INDIRECT
BONDING
P R E S E N T E D BY : -
K U M A R A D A R S H

2. 1. INTRODUCTION
2. TYPES OF TRANSFER TRAYS
3. METHODS OF INDIRECT BONDING
1. THOMAS METHOD
2. KNIGHTS METHOD
3. SONDHIS METHOD
• CONCLUSION
2

3. INTRODUCTION
• In the past, the best clinical results were
achieved by orthodontists who had the best
wire bending skills. However, "the best results
in the present and in future will be achieved
by those orthodontists who are best at
accurate bracket positioning"
3

4. • For the past 50 years, since the introduction of
acid etching by Buonocore in 1955, major
improvements were achieved in bonding brackets
to the teeth.
• In 1964, Newman first tried to bond orthodontic
brackets to teeth using acid etch technique and
an epoxy-derived resin.
4

5. • To reach the goals of better bonding Silverman and
Cohen introduced the first indirect-bonding method
in 1974.
• They used methyl methacrylate adhesive to attach
brackets to model casts in the laboratory.
• An unfilled BisGMA resin was used as an adhesive
between the etched enamel and a previously placed
adhesive.
5

6. Direct Bonding Indirect Bonding
Description Brackets placed directly on
tooth one at a time, and
adjusted by orthodontist until
reasonable position achieved
Brackets placed on models of
patient’s teeth. Full set of
brackets transferred to mouth
with transfer tray
Chair time 1.5 to 3 hours (Full Set) 30- 45 minutes (Full Set)
Accuracy Low to Moderate (Accuracy
decreases in posterior region)
High
Patient Comfort Moderate High
Results Variable: subsequent bonding
appointments needed to
reposition brackets for
Quick, Precise Bracket
Placement
INDIRECT BONDING OVER DIRECTBONDING

7. TYPES OF TRANSFER TRAYS
• Polyvinyl Silicone – Putty
– Putty and activator are mixed in a kneading action and rolled cylindrically
Thomas RG. Indirect bonding, simplicity in action. J Clin Orthod. 1979;13:93–105

8. • Reprosil impression material tray- is applied with a syringe

9. • Clear Polyvinyl Siloxane Trays

10. • Bioplast or biocryl trays- A Biostar unit to vaccum form a 1 mm thick
layer of Bioplast, overlayered with a 1 mm thick layer of Biocryl sheet
is used.
Ref:-Sondhi A. Efficient and effective indirect bonding. Am J Orthod Dentofacial
Orthop. 1999;115:352–359

11. • Light polymerized resin composite trays
First, block out the bracket undercuts and slots with
plaster.
Coat the blocked-out bracket with a resin separator, and
cover it with a quick-curing acrylic resin
RYOON-KI HONG et al JCO/AUGUST 2000

12. • Surebonder DT-200 hot glue gun
– uses a polymer of ethylene vinyl acetate to form a clear transfer tray
matrix for transferring accurately placed brackets to the teeth
•White L. “New and improved indirect bonding technique” J Clin Orthod 1999; 33:17-23

13. PREVIOUS RESINS USED IN
INDIRECT BONDING
• With the increasing popularity of indirect
bonding over the past 2 decades, different
methods of bonding the brackets to the teeth
have been developed.
• When brackets had been positioned on the
models with candy or various glues, the bonding
was accomplished with a filled resin, such as
Concise.
• The indirect transfer trays usually were formed
with silicone tray materials.
13

14. • It became increasingly evident that one of the deficiencies
in the available systems came from the fact that all the
resins and procedures originally had been designed for
direct bonding and subsequently had been adapted for
indirect bonding.
• The property of working time for the adhesive has no
advantage in indirect bonding because an extended cure
time is unnecessary once the tray has been placed. This
led to the development of a resin designed specifically for
indirect bonding. After some innovation, laboratory
testing, and clinical trials, an efficient and effective
indirect bonding procedure has been developed.
14

15. DEVELOPMENT OF A
CUSTOMIZED RESIN BASE• In an effort to determine the best method for preparing a
custom resin base, a number of clinical trials were attempted.
It is found that a light cured resin is a quick and efficient
material for placing brackets on models and for forming a
custom resin base.
• Use of adhesive precoated brackets eliminates
contamination and reduces laboratory time to a minimum
because individual brackets do not need to be sorted or have
resin applied to the base before placing on the model.
• If precoated brackets are not used, then it is recommended
to use Transbond XT as the material of choice for preparing
the resin bases.
15

16. A NEW INDIRECT BONDING
RESIN
• This material was designed with several objectives in mind.
An unfilled resin lacks any Significant viscosity and is not
capable of filling the small imperfections in the custom
base formed with light cured resin or any imperfections in
the fit of the custom base against the enamel.
• The viscosity of this resin was increased using a fine
particle fumed silica filler(about 5%) so that it would be
capable of filling such voids without compromising any
bond strength.
• The resin was developed with a quick set time of 30
seconds, thereby significantly decreasing the time needed
to hold the bonding tray.
16

17. VARIOUS METHODS OF
INDIRECT BONDING
17
Many techniques are available which differ by
• The way brackets are attached temporarily to
models.
• Type of transfer trays used.
• Adhesive or sealant employed.

19. THOMAS INDIRECT BONDING TECHNIQUE -
( DOUBLE SEALANT TECHNIQUE)
Laboratory Procedure
• An excellent alginate impression
• Separate, fill any holes
• Allow model to dry overnight.
• Small dots of each bonding resin paste-Catalyst
and Universal resin is placed side by side on a
paper mixing pad.
• Bracket position on model
19

20. • Dots of bonding resin is mixed and applied to the back of
the bracket base.
• Excess flash is removed
• Allow bonding material to set at least 10 minutes before
forming tray.
• Now the tray material is cut
• The model is dipped into water (3-5 seconds) and placed
under a dry heat source with the arch blank on top.
20

21. • The model with the heated arch blank is placed in the
vacuum former and vacuum is applied.
• After good adaptation has been achieved, cold water
is poured into the top of the vacuum former to
hasten the cooling of the tray material.
• The model is now removed from the vacuum former
and placed into a bowl of water until it is saturated.
• This allows the bonding agent to be released from
the stone before the tray is removed from the model.
21

22. • The tray is removed and trimmed 1-2 mm away from the
clinical crowns of the teeth with lab scissors.
• The tray is then cleaned under running water with a brush.
• The midlines of the tray are marked with a Marker, to
help identify the midline during bonding.
• The backs of the bases are lightly abraded with a stone
point. Air is blown to eliminate residue.
22

23. Clinical Procedure
• antisialagogue like Banthine 30 minutes before starting
the procedure.
• The inside of the tray is then painted with liquid "sealant"
catalyst resin.
• All teeth that are to receive brackets are polished.
• The teeth are conditioned using a small sponge pellet
soaked in 37% phosphoric acid for 30 seconds.
23

24. • The conditioner is thoroughly rinsed from the teeth and the teeth are
again air dried.
• The teeth are painted with liquid "sealant" Universal resin.
• The tray is then inserted into the mouth, seated fully and held to
place for 1½ minutes. These same procedures are then repeated in
the opposite arch before removal of the tray.
• The tray is then removed from the mouth from the lingual toward the
buccal, peeling the tray off, leaving the brackets behind.
• Dental floss should be passed through each individual contact to
ensure that no bridging has occurred.
24

25. 2. KNIGHTS METHOD -
• The Thomas technique is the foundation for contemporary indirect
bonding.
• In this procedure, the brackets, with filled composite on their bases,
are bonded directly to the working casts.
• After bracket positions are accurately recorded with a plastic
template, the unfilled resin (sealant) is added to both the tooth
surfaces and the composite bases.
• The entire tray, with the brackets encased, is seated in place, resulting
in minimal flash and relatively easy clean-up.
• The following indirect-bonding technique is a modification of the
Thomas technique using Therma Cure composite and Light vinyl
polysiloxane impression material.
25

26. Impressions for Indirect Working Casts – it’s the
same as for Thomas technique.
Preparation of Working Casts
1. Pour the impressions immediately in a hard
stone.
2. After the stone has set, the casts are separated
from the impression trays. When the casts are
dry, fill in any voids with a light-cured
gel, and cure for 20-30 seconds.
26

27. 3. the incisal edges, mesiodistal center points, and long
axes of the teeth on each cast are marked with a pencil,
along with the preferred incisogingival positions of the
bracket slots.
4. Two thin coats of liquid separating medium is applied to
the facial surfaces of the teeth on the cast, and allowed it
to dry.
27

28. Placement of Brackets on Cast
1. The Therma Cure composite resin is applied to the mesh pad
of each bracket, using a “buttering” motion to cover all of the
mesh.
2. The brackets on each cast are placed with firm pressure, and
positioned according to the pencil marks.
28

29. Curing of Composite Resin
1. The casts are placed in a heated oven to
cure .(Therma Cure requires 15 minutes at 325°F. )
2. The casts are allowed to cool, and removed from
oven.
29

30. Fabrication of Transfer Trays
1. Reprosil impression material is applied with a syringe over
the thermally cured brackets from the facial surfaces, and
cover each bracket.
2. The material is extended onto the occlusal or incisal
and partly onto the lingual surfaces, but the undertray
not be made unnecessarily thick.
30

31. 2. Vacuum-form Essix .020" (.5mm) or .030" (.75mm)
clear thermoplastic material over the cast,
brackets, and undertray complex.
31

32. • After cutting away the excess thermoplastic material, the
assembly is soaked in warm water for about five minutes, then
both the trays are separated from the cast.
• Trim the trays with scissors. Rinse away residual solidified
release material and other debris from the undertray and
brackets.
• Inspect the composite pads, and trim off any flash.
32

33. Chair side Bonding Procedure
1. To remove the air-inhibited layer of adhesive, lightly
abrade the composite on the back of each bracket base
with a diamond bur or Microetcher, or simply scrape the
composite base with a cleioid instrument.
33

34. 2. Isolate a single arch, etch the enamel, and rinse. Dry with an air
syringe.
34

35. 3.Mix two drops each of Enhance A and B primer. Apply the mixture to
the composite bases and the tooth surfaces.
35

36. 4. Mix unfilled bonding resin, and quickly apply it to the
composite bases of the brackets and to the teeth .
36

37. 5. Seat the tray immediately . Hold the tray in place for one minute,
then allow the tray to remain in place for about 4 more minutes.
37

38. 6. Remove the clear overtray material.
38

39. 7. Tear the flexible undertray from the teeth with an
explorer or scaler .
Use a gentle, rolling motion from the lingual surface of the
flexible tray to avoid dislodging the brackets.
39

40. 8. Inspect the brackets. Floss interproximally to
remove any bridging of the unfilled resin. There
should be virtually no flash of filled bonding resin
around the bracket bases.
40

41. SONDHIS METHOD
Laboratory procedure
Preparation of bonding trays
1. Working models in orthodontic stone, prepared from
accurate alginate impressions, are necessary.
41

42. 2. A thin layer of separating medium should be applied to
the models and allowed to dry for approximately 1 hour.
42

43. 3. If Adhesive Coated brackets are used, the preoriented
brackets may be removed directly from the sealed blister
and positioned on the individual teeth. The excess
adhesive should be removed, and the position of the
bracket carefully checked with a bracket gauge.
If noncoated brackets are used, then Transbond XT Light
Cure adhesive should be placed on the mesh pad of
individual brackets before they are positioned on the
model.
43

44. 4. Once all brackets have been placed, any excess should be
removed.
5. Once all the bracket positions have been checked, the
upper and lower models should be placed in the curing
unit and cured for 10 minutes.
44

45. 6. Before forming the indirect bonding trays, it is
recommended that significant undercut areas, such as
hooks, be blocked out with wax.
45

46. 7. The indirect bonding trays can now be placed over the
brackets .
1 mm thick layer of Bioplast, overlayered with a 1 mm thick
layer of Biocryl is used
46

47. 8. The bonding trays are now removed from the models
and may have to be sectioned off with a bur. It may be
necessary to tease the tray off with a scaler.
47

48. CLINICAL PROCEDURE :
Preparation of the patient
1. Pumice all teeth.
2. Rinse and suction well with water.
3. If there are bands to fit, this should be completed after the
indirect bonding procedure has been completed.
48

49. Placement of Bonding
1. Whether the indirect bonding procedure can be
completed with a single tray for the entire arch or
whether the tray needs to be sectioned into two
segments is a decision based primarily on the degree of
isolation that is feasible. If there is significant crowding, it
may be easier to section the tray.
2. Examine the trays carefully for any remaining separator
or tray material covering the adhesive custom base on
bracket.
49

50. 3. Isolate the teeth that are to be bonded with plastic cheek
retractors, Tongue Away, and cotton rolls.
4. Using air syringe, dry teeth thoroughly.
5. Etching solution is applied onto the teeth and kept for 15
seconds.
6. After 15 seconds, rinse with a steady stream of water for
15 seconds.
50

51. 7. A. If the clinician chooses to use Moisture Insensitive
Primer on the enamel surface before the indirect bonding
procedure, then the air syringe should be used to remove
excess moisture.
B. If Transbond MIP is not used, and the bonding is
accomplished with the indirect bonding resin, then all
visible moisture should be removed. The etched teeth
should have a frosty appearance. If a frosty appearance is
not apparent, repeat the etching process for 15 seconds.
51

52. 8. Small amounts of the indirect bonding Resin A and B
liquids (Sondhi rapid set) should be poured into the
wells. Care should be taken to keep liquids separate.
52

53. Resin A can be painted onto the tooth surface with a brush,
and Resin B can be painted on the resin pads in the
indirect bonding tray.
53

54. 9. If too much resin has been placed on the enamel,
gently remove the excess with a brush.
10. Position the tray over the teeth and seat the tray
with a hinge motion. With the fingers, apply equal
pressure to the occlusal, labial, and buccal surfaces.
Hold for a minimum of 30 seconds. Allow 2 more
minutes of cure time before removing the tray.
54

55. A, Placement of mandibular bonding tray. B. maxillary and
mandibular bonding trays in place. C. removal of mandibular
bonding tray. 55

56. 11. Remove the tray by using a scaler to peel the tray
from the lingual to buccal. Use extreme care when
removing the tray from around bracket wings.
56

57. Disadvantages of indirect bonding
• Technique sensitive.
• Increased lab time.
• Risk of adhesive leakage to gingival embrasure could
lead to difficult oral hygiene management. ANGLE
2004 by Polat et al.
• Removing adhesive is difficult & time consuming.
• Achieving consistent & predictable adhesion is
difficult.
• Accidental removal of brackets with tray is not unusual.
• Adequate bond strength shortly after sealant
application is mandatory.(To withstand force during
tray removal )
• Failure rates are slightly higher – Zachrisson &
Brobakken
57

58. Conclusion
When the laboratory and the clinical procedures are strongly
adhered, indirect bonding is undoubtedly a valuable
It proves itself by saving chair side time which is the most
valuable for a practitioner as better treatment results can be
obtained if the brackets are positioned accurately.

59. REFERENCES
• Xubair,grabber,vanarsdall,vig;Orthodontics current principles
and techniques,5th edition
• Thomas RG. Indirect bonding, simplicity in action. J Clin Orthod.
1979;13:93–105
• Knight RG; a new look at indirect bonding; J Clin Orthod 1996,
30(5);277-81
• Sondhi A; Efficient and effective indirect bonding, Am J Orthod
Dentofacial Orthop 1999;115:352-9

60. Thank
you…