This document provides an overview of implant impressions presented by Dr. Vaishali Shrivastava. It discusses the need for accurate implant impressions, common impression materials and techniques. Conventional impression techniques include closed and open tray methods. Digital implant impressions using intraoral scanners are also described. The advantages and disadvantages of different techniques are reviewed. Several studies comparing the accuracy of impression materials and techniques are summarized. Overall, the review found no significant differences between open and closed tray techniques, but open tray may be more accurate for non-parallel implants. Digital impressions provided more accurate results than conventional methods in some studies.

1. IMPRESSIONS IN IMPLANTS
PRESENTED BY-DR.VAISHALI SHRIVASTAVA.
PG 2NDYEAR STUDENT.
DEPT. OF PROSTHODONTICS ,CROWN & BRIDGE &
IMPLANTOLOGY. 1

2. CONTENTS
• INTRODUCTION
• NEED FOR IMPRESSION MAKING
• IMPRESSION MATERIALS
• TYPES OF IMPRESSION PROCEDURE
• DIGITAL IMPLANT IMPRESSION
• LITERATURE REVIEW
• CONCLUSION
• REFERENCES
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3. • Dental implants have become a quite successful method for restoration of fully and
partially edentulous patients.
• The critical aspect is to record the spatial intraoral orientation of the implant, and
replicating minute surface detail
INTRODUCTION
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4. NEED FOR IMPLANT IMPRESSION
Position
Depth
Axis (Angulation)
Soft tissue contour
( Emergence profile)
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5. Poly Vinyl
Siloxane
Poly ether
Other
hydrocolloids
Poly sulfide
IMPRESSION MATERIALS
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6. TYPES
CONVENTIONAL DIGITAL
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7. IMPRESSION TECHNIQUES
CLOSED TRAY TECHNIQUE
1. Make sure all the necessary parts are on hand (such as impression posts and screwdrivers)
before seeing the patient.
Tip: Be careful; the healing cap or cover screw can require a different screwdriver from the
impression post or abutment.
2. Remove the healing cap from the patient’s mouth and store it within easy reach. If you are
dealing with multiple implants, lay the healing caps in order so they will not be mixed up.
Tip: Remove only one healing cap at a time and place the impression post before taking the
next healing cap off.
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8. 3. Place the corresponding impression posts onto the implant by rotating the antirotation
device (a hex, octagon, or three notches) in position until you feel the drop or lock of the
impression post. Only hand-tighten the screw .
4. Take an x-ray horizontal to the platform of the implant to verify that there is no gap
between the two components. If a gap or misfit between the two parts can be seen, seat the
impression post one more time.
Tip: It is possible that debris, plaque, or overgrown bone is on the implant platform. Also,
the flare of the impression post could be in contact with the surrounding bone. In this case,
debris, plaque, or bone should be removed or recontoured
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9. 5. Take a full-arch impression with a conventional crown and bridge heavy- and light body
impression material. The full-arch impression is necessary for the laboratory to reproduce all
detectable functions of the patient.
Tip: Make sure to apply the light body around the impression post and then place the loaded
impression tray as would be done on a crown and bridge impression.
6. Remove the tray after the impression material has fully set. The impression post will stay
on the implant. Check for any air pockets or voids surrounding the impression post area.
.
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10. 7. Unscrew the impression posts and immediately place the corresponding healing cap on
the implant to prevent the collapse of the soft tissue.
Tip: When dealing with more than one implant, it is important that each impression post is
packed separately with the corresponding tooth number.
IMPORTANT: Please send the following items to the laboratory: impression, impression
post, x-ray of the impression posts in position, opposing model, bite, and all necessary
instructions. Also be sure to include the type, size, and manufacturer of the implan
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11. 11

12. 12

13. Indications
Liou Ad (1993)
Limited inter arch space
Tendency to gag
Difficult access in the posterior region of the mouth
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14. 14
Advantages of Closed Tray
Easier
Suitable for short inter arch distance.
Visual fastening of the analog to the coping is more accurate
Disadvantages of Closed Tray
Inaccuracies with recovery and subsequent deformation of impression material may be
encountered with nonparallel implants.
Not Suitable for deeply placed implants.

15. OPEN TRAY TECHNIQUE
1. Make sure all necessary parts are on hand (such as impression posts and
screwdrivers) before seeing the patient.
Tip: Be careful; the healing cap or cover screw can require a different screwdriver from
the impression post or abutment.
2. Remove the healing cap from the patient’s mouth and store it within easy reach. If
you are dealing with multiple implants, lay the healing caps in order so they will not be
mixed up.
Tip: Remove only one healing cap at a time and place the impression post before taking
the next healing cap off. This will help prevent the collapse of the soft tissue
15

16. 3. Place the corresponding impression posts onto the implant by rotating the
antirotation device (a hex, octagon, or three notches) in position until you feel the
drop or lock of the impression post. Only hand-tighten the screw.
Tip: For additional accuracy connect all impression posts with dental floss. Then
apply GC pattern resin (GC America Inc., Alsip, IL) or a light-curing composite
around the impression posts and floss before taking the impression (Figure 28-4).
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17. 17

18. 4. Take an x-ray horizontal to the platform of the implant to verify that there is no gap
between the two components. If a gap or misfit between the two parts can be seen, seat
the impression post one more time.
Tip: It is possible that debris, plaque, or overgrown bone is on the implant platform.
Also, the flare of the impression post could be in contact with the surrounding bone. In
this case, debris, plaque, or bone should be removed or recontoured
18

19. 5. A plastic stock tray is widely used for the open tray procedure. Grind a hole in the
tray directly over the impression posts, and verify that the impression posts are
accessible through the hole
19

20. 6. Take a full-arch impression with a conventional crown and bridge heavy- and light-body
impression material.
The full-arch impression is necessary for the laboratory to reproduce all detectable functions
of the patient. As the material begins to set, wipe off the excess from the hole so you can see
the screw heads
Tip: Blowing low pressure air onto the soft impression material disperses the impression
material away from the screw heads
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21. 7. After the material is fully set, unscrew and remove the retaining screw from the impression
post. Next, take the impression out. The impression post will be secured in the impression.
The screws should be packed and numbered separately.
8. Reinsert the healing caps
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22. 22

23. Indications More accurate for multi unit impressions
In cases with implant/abutment angulations and path of insertion withdrawal
Advantages of Open Tray
An advantage of this technique is the dentist can confirm the laboratory preparation and
contour of the provisional prosthesis to achieve the desired healing and soft tissue contour
before final crown fabrication.
Reduces the deformation of the impression material.
Removes the concern for replacing the coping back into its respective space in the
impression
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24. Disadvantage of Open Tray
The movement of impression copings inside the impression material
during clinical and laboratory phases may cause inaccuracy in transferring
the spatial position of implants from the oral cavity to the master cast
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25. 25

26. Direct technique
Here impression is taken with abutment and transfer coping.
The abutment is then removed from the patients mouth and this same abutment
is used for casting and fabrication of the prosthesis.
Since we use the abutment directly it is called direct technique.
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27. Snap-fit (press fit) plastic impression coping
This technique uses press-fit impression coping which is connected to the implant by
pressing instead of screwing and the plastic impression copings are picked up in the
impression.[Nissan J, Ghelfan O,2009]
This technique is not a pickup impression because it does not require an open tray, but
instead uses a closed tray.
It is not a transfer impression, either, because the plastic impression copings are picked up
in the impressions
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28. Advantages
1. Helps to overcome the movement of impression coping inside the impression
material
2. Time saving
3. Has the advantage of both the open and closed tray implant impression
techniques
4. More comfortable for both the clinician and the patient
5. Easy to manipulate
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29. 29

30. DIGITAL IMPLANT IMPRESSION
More recently, one of the major developments in implant prosthodontics has been the
adoption of engineering principles in the form of computer-aided design and computer
aided manufacturing (CAD/CAM) to construct implant prosthesis.
This technology utilizes 3-D intraoral scanners which has revolutionizing the way we
take impressions .
The digital implant impression technique has proven its possibilities as an effective
alternative for the analogue impression-taking technique
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31. The main requirements for the CAD/CAM are the
(1)the digital scanner, which scans and transforms the geometry into the
digital data which can be processed by the computer
(2) software that processes the data and creates a CAD model
(3) a production technology that transforms the data set into the desired
product by means of CAM [Jaafar Abduo, Karl Lyons,2013]
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32. • Intraoral digital impression systems have been commercially available for more than
25 years.
• The first scannable implant was introduced in 2004 (BIOMET 3i); it utilized a
coded implant healing abutment.
• This abutment provided all the 3-dimensional information of the location of the
dental implant in relation to the adjacent and opposing teeth.
• in 2010 unique scannable impression copings (scan bodies) were introduced, which
could be placed on the implant and scanned.
Wilk BL. Intraoral digital impressioning for dental implant restorations versus traditional implant impression techniques. Compend Contin Educ Dent. 2015 Jul;36(7). 32

33. There are two basic types of scanners available today:
either a blue LED (light emitting diode) type, which is considered an optical scanner
scanners that use lasers to scan and record distances from the tooth surface to capture
the image and build the digital model.
33

34. Wilk BL. Intraoral digital impressioning for dental implant restorations versus traditional implant impression techniques. Compend Contin Educ
Dent. 2015 Jul;36(7). 34

35. 35

36. Advantages
1.Improved patient acceptance
2.Reduced distortion of impression materials
3.Pre-visualization of the preparation three-dimensionally
4.Virtual assessment of the implant prosthetic space
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37. Disadvantages
(1) Its More easy to carry out in the maxilla due to direct view.
(2) In case of multiple implants difficult to identify the position of the abutments.
(3) Inability to scan the proximal area of the neighbouring tooth when situate too close to
the abutment.[Wismeijer, R. Mans, M. van Genuchten, H. A. Reijers.,2013]
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38. Conclusions:
Within the limitations of this study, there were generally
no significant differences between open and closed,
although better results were obtained for the open tray
techniques.
On the use of the non-parallel implants, the open tray
technique provided a better result than the closed tray
technique
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39. Conclusion:
The accuracy of open and closed-tray impression
techniques showed no statistically significant
differences and both techniques were effective
for implant transfer.
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40. 40

41. Results. All of the selected articles were in vitro studies. Of the 17 studies that compared the accuracy
between the splint and nonsplint techniques, 7 advocated the splint technique, 3 advocated the nonsplint
technique, and 7 reported no difference.
Fourteen studies compared the accuracy of pick-up and transfer impression techniques, and 5 showed
more accurate impression with the pick-up techniques, 2 with the transfer technique, and 7 showed no
difference. The number of implants affected the comparison of the pick-up and splint techniques.
Eleven studies compared the accuracy of polyether and vinyl polysiloxane (VPS), and 10 of 11 reported
no difference between the 2 materials.
Four studies examined the effect of implant angulation on the accuracy of impressions.
Two studies reported higher accuracy with straight implants, while the other 2 reported there was no
angulation effect
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42. Conclusions.
The review of abutment level or implant level internal connection implants indicated that
more studies reported greater accuracy with the splint technique than with the nonsplint
technique.
For situations in which there were 3 or fewer implants, most studies showed no difference
between the pick-up and transfer techniques, whereas for 4 or more implants, more studies
showed higher accuracy with the pick-up technique.
Polyether and VPS were the recommended materials for the implant impressions. (J Prosthet
Dent 2008;100:285-291)
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43. Results: There was a general tendency for digital
impressions to provide a more accurate outcome for
trueness, precision, and angle deviation. The 2
conventional impressions showed similar accuracy,
except for the angle deviation, where the NSP was
significantly inferior than SP (p < 0.01) for the divergent
implants model.
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44. Conclusion
One of the critical factors which affect the long term success of the implant is its
passive fit of the implant prosthesis.
In order to achieve this a clinician should have sound knowledge regarding the
components used during impression, the choice of impression materials and the
selection of suitable impression techniques based on clinical situation.
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45. REFERENCES
Dental implants- the art and science by Charles A babbush 2nd edition
Contemporary of dental implant by Carl E Misch
Liou A D, Nicholls J I, Yuodelis R A, Brudvik J S. Accuracy of replacing three tapered transfer impression
copings in two elastomeric impression materials. Int J Prosthodont 1993; 6: 377-383
Dr.Susanna S Brainerd. , ――Impression Techniques in Implant Dentistry.‖.‖. ‖ IOSR Journal of Dental and
Medical Sciences (IOSR-JDMS), vol. 17, no. 11, 2018, pp 33-44
Swapna B, Kamath V. Digital Impressions In Prosthodontics–An Overview. J Crit Rev. 2020;7(14):733-5.
Wilk BL. Intraoral digital impressioning for dental implant restorations versus traditional implant impression
techniques. Compend Contin Educ Dent. 2015 Jul;36(7).
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