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6 Checklist and Step-by-Step Protocol to Maximize Impression Accuracy
P. Papaspyridakos and T. R. Schoenbaum
Fig. 10.3 (a) Missing right lateral and central incisors and left central incisor (#7, 8, and 9) were
replaced with two dental implants for a three-unit implant-supported fixed dental prosthesis (FDP).
After successful osseointegration, peri-implant soft tissue conditioning was done for a period of
3 months with a provisional screw-retained FDP. (b) Partially edentulous area after peri-implant
soft tissue conditioning. (c) Customized impression copings duplicating the transmucosal part of
the provisional implant FDP. The indirect technique was used for fabrication of the customized
copings. (d) Customized impression copings placed intraorally, after removal of the provisional
implant FDP. Copings are splinted together with prefabricated light polymerized resin bar, in order
to enhance the accuracy of the implant impression. Minimal amount of light polymerizing resin
was used to lute the prefabricated resin bars to the copings. (e) Working cast poured only in stone
without soft tissue moulage. The customized impression copings have captured the transmucosal
part of the provisional implant FDP, guiding the laboratory technician to precisely duplicate the
transmucosal part into the emergence profile of the final FDP. (f) Screw-retained final FDP seated
on the working cast. The emergence profile and transmucosal contours of the final FDP are a duplicate of the provisional FDP, captured with the customized implant impression. Note the palatal
windows to confirm accurate seating of the FDP to the implant prosthetic platforms
10 Enhanced Implant Impression Techniques to Maximize Accuracy
1.Gallucci GO, Benic GI, Eckert SE, Papaspyridakos P, Schimmel M, Schrott A, Weber
HP. Consensus statements and clinical recommendations for implant loading protocols. Int J
Oral Maxillofac Implants. 2014;29(Suppl):287–90.
2.Jemt T, Hjalmarsson L. In vitro measurements of precision of fit of implant-supported frameworks. A comparison between “virtual” and “physical” assessments of fit using two different
techniques of measurements. Clin Implant Dent Relat Res. 2012;14(Suppl 1):e175–82.
3. de Torres EM, Barbosa GA, Bernardes SR, de Mattos Mda G, Ribeiro RF. Correlation between
vertical misfits and stresses transmitted to implants from metal frameworks. J Biomech.
4.Duyck J, Naert I. Influence of prosthesis fit and the effect of a luting system on the prosthetic
connection preload: an in vitro study. Int J Prosthodont. 2002;15:389–96.
5.Eckert SE, Meraw SJ, Cal E, Ow RK. Analysis of incidence and associated factors with fractured implants: a retrospective study. Int J Oral Maxillofac Implants. 2002;15:662–7.
6.Papaspyridakos P, Chen CJ, Chuang SK, Weber HP, Gallucci GO. A systematic review of
biologic and technical complications with fixed implant rehabilitations for edentulous patients.
Int J Oral Maxillofac Implants. 2012;27:102–10.
7.Papaspyridakos P, Lal K, White GS, Weber HP, Gallucci GO. Effect of splinted and nonsplinted impression techniques on the accuracy of fit of fixed implant prostheses in edentulous
patients: a comparative study. Int J Oral Maxillofac Implants. 2011;26:1267–72.
8.Papaspyridakos P, Chen CJ, Gallucci GO, Doukoudakis A, Weber HP, Chronopoulos
V. Accuracy of implant impressions for partially and completely edentulous patients: a systematic review. Int J Oral Maxillofac Implants. 2014;29:836–45.
9.Chai J, Takahashi Y, Lautenschlager EP. Clinically relevant mechanical properties of elastomeric impression materials. Int J Prosthodont. 1998;11:219–23.
10.Akca K, Cehreli MC. Accuracy of 2 impression techniques for ITI implants. Int J Oral
Maxillofac Implants. 2004;19:517–23.
11. Assuncao WG, et al. Accuracy of impression techniques for implants. Part 1-influence of transfer copings surface abrasion. J Prosthodont. 2008;17:641–7.
12.Assuncao WG, et al. Prosthetic transfer impression accuracy evaluation for osseointegrated
implants. Implant Dent. 2008;17:248–56.
13. Assuncao WG, Filho HG, Zaniquelli O. Evaluation of transfer impressions for osseointegrated
implants at various angulations. Implant Dent. 2004;13:358–66.
14.Cabral LM, Guedes CG. Comparative analysis of 4 impression techniques for implants.
Implant Dent. 2007;16:187–94.
15. Choi JH, et al. Evaluation of the accuracy of implant-level impression techniques for internal-
connection implant prostheses in parallel and divergent models. Int J Oral Maxillofac Implants.
16.Inturregui JA, et al. Evaluation of three impression techniques for osseointegrated oral
implants. J Prosthet Dent. 1993;69:503–9.
17. Filho HG, et al. Accuracy of impression techniques for implants. Part 2 - comparison of splinting techniques. J Prosthodont. 2009;18:172–6.
18. Lee HJ, et al. Accuracy of a proposed implant impression technique using abutments and metal
framework. J Adv Prosthodont. 2010;2:25–31.
19. Lee YJ, et al. Accuracy of different impression techniques for internal-connection implants. Int
J Oral Maxillofac Implants. 2009;24:823–30.
20.Rutkunas V, Sveikata K, Savickas R. Effects of implant angulation, material selection, and
impression technique on impression accuracy: a preliminary laboratory study. Int J Prosthodont.
21. Tarib NA, et al. Evaluation of splinting implant impression techniques: two dimensional analyses. Eur J Prosthodont Restor Dent. 2012;20:35–9.
22.Yamamoto E, et al. Accuracy of four transfer impression techniques for dental implants: a
scanning electron microscopic analysis. Int J Oral Maxillofac Implants. 2010;25:1115–24.
P. Papaspyridakos and T. R. Schoenbaum
23.Al-Abdullah K, et al. An in vitro comparison of the accuracy of implant impressions with
coded healing abutments and different implant angulations. J Prosthet Dent. 2013;110:90–100.
24. Mojon P, Oberholzer JP, Meyer JM, Belser UC. Polymerization shrinkage of index and pattern
acrylic resins. J Prosthet Dent. 1990;64:684–8.
25.Gracis S, Michalakis K, Vigolo P, Vult von Steyern P, Zwahlen M, Sailer I. Internal vs. external connections for abutments/reconstructions: a systematic review. Clin Oral Implants Res.
26. Alikhasi M, et al. Three-dimensional accuracy of implant and abutment level impression techniques: effect on marginal discrepancy. J Oral Implantol. 2011;37:649–57.
27. Carr AB. Comparison of impression techniques for a two-implant 15-degree divergent model.
Int J Oral Maxillofac Implants. 1992;7:468–75.
28.Cehreli MC, Akca K. Impression techniques and misfit-induced strains on implant-supported
superstructures: an in vitro study. Int J Periodontics Restorative Dent. 2006;26:379–85.
29.Conrad HJ, et al. Accuracy of two impression techniques with angulated implants. J Prosthet
30.De La Cruz JE, et al. Verification jig for implant-supported prostheses: a comparison of
standard impressions with verification jigs made of different materials. J Prosthet Dent.
31.Howell KJ, et al. Comparison of the accuracy of Biomet 3i Encode Robocast Technology and
conventional implant impression techniques. Int J Oral Maxillofac Implants. 2013;28:228–40.
32.Gallucci GO, Papaspyridakos P, Chen CJ, Kim EG, Brady NJ, Weber HP. Clinical accuracy
outcomes of closed-tray and open-tray implant impression techniques for partially edentulous
patients. Int J Prosthodont. 2011;24:469–72.
33.Jo SH, et al. Effect of impression coping and implant angulation on the accuracy of implant
impressions: an in vitro study. J Adv Prosthodont. 2010;2:128–33.
34.Wegner K, Zenginel M, Rehmann P, Wöstmann B. Effects of implant system, impression
technique, and impression material on accuracy of the working cast. Int J Oral Maxillofac
35. Wostmann B, Rehmann P, Balkenhol M. Influence of impression technique and material on the
accuracy of multiple implant impressions. Int J Prosthodont. 2008;21:299–301.
36. Daoudi MF, Setchell DJ, Searson LJ. A laboratory investigation of the accuracy of two impression techniques for single-tooth implants. Int J Prosthodont. 2001;14:152–8.
37.Daoudi MF, Setchell DJ, Searson LJ. An evaluation of three implant level impression techniques for single tooth implant. Eur J Prosthodont Restor Dent. 2004;12:9–14.
38. Chochlidakis KM, Papaspyridakos P, Geminiani A, Chen CJ, Feng IJ, Ercoli C. Digital versus
conventional impressions for fixed prosthodontics: a systematic review and meta-analysis. J
Prosthet Dent. 2016;116:184–90.
39.Ender A, Attin T, Mehl A. In vivo precision of conventional and digital methods of obtaining
complete-arch dental impressions. J Prosthet Dent. 2016;115:313–20.
40.Papaspyridakos P, Gallucci GO, Chen CJ, Hanssen S, Naert I, Vandenberghe B. Digital versus conventional implant impressions for edentulous patients: accuracy outcomes. Clin Oral
Implants Res. 2016;27:465–72.
41.Gherlone E, Cappare P, Vinci R, Ferrini F, Gastaldi G, Crespi R. Conventional versus digital
impressions for “all-on-four” restorations. Int J Oral Maxillofac Implants. 2016;31:324–30.
42.Gimenez-Gonzalez B, Hassan B, Ozcan M, Pradies G, et al. J Prosthodont. 2017;26:650.
[Epub ahead of print].
43.Vandeweghe S, Vervack V, Dierens M, De Bruyn H. Accuracy of digital impressions of multiple dental implants: an in vitro study. Clin Oral Implants Res. 2017;28:648. [Epub ahead of
44.Lee SJ, Betensky RA, Gianneschi GE, Gallucci GO. Accuracy of digital versus conventional
implant impressions. Clin Oral Implants Res. 2015;26:715–9.
45. Lin WS, Harris BT, Elathamna EN, Abdel-Azim T, Morton D. Effect of implant divergence on
the accuracy of definitive casts created from traditional and digital implant-level impressions:
an in vitro comparative study. Int J Oral Maxillofac Implants. 2015;30:102–9.
10 Enhanced Implant Impression Techniques to Maximize Accuracy
46. Joda T, Bragger U. Digital vs. conventional implant prosthetic workflows: a cost/time analysis.
Clin Oral Implants Res. 2015;26:1430–5.
47.Joda T, Katsoulis J, Brägger U. Clinical fitting and adjustment time for implant-supported
crowns comparing digital and conventional workflows. Clin Implant Dent Relat Res.
48. Schepke U, Meijer HJ, Kerdijk W, Cune MS. Digital versus analog complete-arch impressions
for single-unit premolar implant crowns: operating time and patient preference. J Prosthet
49.Wismeijer D, Bragger U, Evans C, Kapos T, Kelly JR, Millen C, et al. Consensus statements
and recommended clinical procedures regarding restorative materials and techniques for
implant dentistry. Int J Oral Maxillofac Implants. 2014;29(Suppl):137–40.
50.Karl M, Graef F, Schubinski P, Taylor T. Effect of intraoral scanning on the passivity of fit of
implant-supported fixed dental prostheses. Quintessence Int. 2012;43:555–62.
51.Schoenbaum TR, Han TJ. Direct custom implant impression copings for the preservation of
the pontic receptor site architecture. J Prosthet Dent. 2012;107:203–6.
52.Lops D, Bressan E, Cea N, Sbricoli L, Guazzo R, Scanferla M, Romeo E. Reproducibility
of buccal gingival profile using a custom pick-up impression technique: a 2-year prospective
multicenter study. J Esthet Restor Dent. 2016;28:43–55.
53.Tan WL, Wong TL, Wong MC, Lang NP. A systematic review of post-extractional alveolar
hard and soft tissue dimensional changes in humans. Clin Oral Implants Res. 2012;23(Suppl
54.Jang HK, Kim S, Shim JS, Lee KW, Moon HS. Accuracy of impressions for internal-
connection implant prostheses with various divergent angles. Int J Oral Maxillofac Implants.
55.Sorrentino R, Gherlone EF, Calesini G, Zarone F. Effect of implant angulation, connection
length, and impression material on the dimensional accuracy of implant impressions: an
in vitro comparative study. Clin Implant Dent Relat Res. 2010;12(Suppl 1):e63–76.
56. Burns J, Palmer R, Howe L, Wilson R. Accuracy of open tray implant impressions: an in vitro
comparison of stock versus custom trays. J Prosthet Dent. 2003;89:2505.
57.Gửkỗen-Rohlig B, Ongül D, Sancakli E, Sermet B. Comparative evaluation of the effects of
implant position, impression material, and tray type on implant impression accuracy. Implant
58.Del’Acqua MA, Arioli-Filho JN, Compagnoni MA, Mollo Fde A Jr. Accuracy of impression
and pouring techniques for an implant-supported prosthesis. Int J Oral Maxillofac Implants.
59.Del’Acqua MA, Chavez AM, Amaral AL, Compagnoni MA, Mollo Fde A Jr. Comparison of
impression techniques and materials for an implant-supported prosthesis. Int J Oral Maxillofac
60. Papaspyridakos P, Benic GI, Hogsett VL, White GS, Lal K, Gallucci GO. Accuracy of implant
casts generated with splinted and non-splinted impression techniques for edentulous patients:
an optical scanning study. Clin Oral Implants Res. 2012;23:676–81.
61. Cheshire PD, Hobkirk JA. An in vivo quantitative analysis of the fit of Nobel Biocare implant
superstructures. J Oral Rehabil. 1996;23:782–9.
62. Ma T, Nicholls JI, Rubenstein JE. Tolerance measurements of various implant components. Int
J Oral Maxillofac Implants. 1997;12:371–5.
63.Gimenez B, Ozcan M, Martinez-Rus F, Pradies G. Accuracy of a digital impression
system based on parallel confocal laser technology for implants with consideration of
operator experience and implant angulation and depth. Int J Oral Maxillofac Implants.
64.Gimenez B, Ozcan M, Martinez-Rus F, Pradies G. Accuracy of a digital impression system
based on active wavefront sampling technology for implants considering operator experience,
implant angulation, and depth. Clin Implant Dent Relat Res. 2015;17(Suppl 1):e54–64.
65.Schoenbaum TR, Swift EJ Jr. Contours for single-unit implants. J Esthet Restor Dent.
P. Papaspyridakos and T. R. Schoenbaum
66.Chu SJ, Salama MA, Salama H, Garber DA, Saito H, Sarnachiaro GO, Tarnow DP. The dual-
zone therapeutic concept of managing immediate implant placement and provisional restoration in anterior extraction sockets. Compend Contin Educ Dent. 2012;33:524–32.
67.Martin WC, Pollini A, Morton D. The influence of restorative procedures on esthetic outcomes in implant dentistry: a systematic review. Int J Oral Maxillofac Implants. 2014;
Emergence Profile of the Implant
Abutment and Its Effects
on the Peri-implant Tissues
Todd R. Schoenbaum and Sam Alawie
The emergence profile is the portion of the implant-abutment-restoration complex that extends from the bone crest to the free gingival margin. Generally this
area is made up of the abutment, though in screw-retained restorations, it is part
of the restoration as a whole. This area is critical to the long-term health and
aesthetics of the rehabilitation in the aesthetic zone. The shape of the emergence
profile is responsible for creating and maintaining the soft tissue architecture.
This proves especially important in the immediate load treatment scenario. It is
critical that the restoring doctor have and understanding of the effects the emergence profile will have on the positioning of the soft tissues. Changes to the
emergence profile (particularly during the healing stages) can be strategically
used to move the tissues apically or coronally and to shape the papilla.
Following surgical placement of the implant and any additional augmentation, the
fine-tuning of the soft tissues (Fig. 11.1) will be largely dependent on the emergence
profile of the abutment (Fig. 11.2). In the aesthetic zone, this is a process best accomplished through the use of a proper provisional restoration or custom healing abutment. When sufficient implant stability exists at placement (i.e., ISQ > 65) , it is
generally easier to preserve and maintain the peri-implant soft tissues with an immediately placed provisional restoration. In cases where implant stability is questionable, the implant should be treated in a two-stage approach or with a custom healing
T. R. Schoenbaum
Division of Constitutive and Regenerative Sciences, University of California, Los Angeles,
Owner/Ceramist Beverly Hills Dental Lab, Beverly Hills, CA, USA
© Springer International Publishing AG, part of Springer Nature 2019
Todd R. Schoenbaum (ed.), Implants in the Aesthetic Zone,
Fig. 11.1 Successful
treatment of implants in the
aesthetic zone requires
proper shaping of the soft
tissue with the provisional
restorations. The surgical
foundation sets the stage for
the prosthetic fine-tuning of
the gingiva. Inadequate bone
and soft tissue cannot be
overcome with tissue
Fig. 11.2 The emergence
area of the abutment is
defined by the area from
the head of the implant to
the free gingival margins
(here, highlighted in blue).
This area is responsible for
the final shaping of the
T. R. Schoenbaum and S. Alawie
11 Emergence Profile of the Implant Abutment and Its Effects
abutment. In the latter case, special care must be given to ensure that the removable
provisional restoration does not negatively affect the soft tissues during maturation
and osseointegration. The shape of the emergence profile can be altered to move the
tissues to the desired position (with some genetic and biologic limitations) [2–4];
however, removal and alteration of the abutment should be delayed until at least
3 months after implant placement, and the number of times should be limited .
There is solid histological evidence that repeated removal of components from the
implant traumatizes the tissues and results in significant loss of bone and soft tissue.
This is especially true during the first few months of healing and maturation. Dr. Vela
and Dr. Rodriguez provide an in-depth look at this process in the last chapter.
This chapter will focus on the emergence profile of the provisional restoration
fabricated and delivered at the time of immediate implant placement to replace a
single tooth in the aesthetic zone. Similar concepts should be applied for the use of
a custom healing abutment or delivery of a provisional restoration at the stage 2
surgery. More information on the fabrication of provisional restorations can be
found in Chap. 8.
11.1 The Peri-implant Tissues: Tooth vs. Implant
Surrounding the natural tooth is a densely collagenous gingiva made up of type 1
collagen. The periodontal gingival fibers are anchored into the cementum on the
root surface via Sharpey’s fibers, the same mechanism through which the periosteum is attached to the underlying bone. The gingival fibers serve to protect the
tooth from the oral environment and provide anchorage for the gingiva. The fibers
are categorized by their location and orientation into five groups: gingivodental
fibers, transseptal fibers, semicircular fibers, transgingival fibers, and circular fibers.
All but the last type (circular fibers) insert into the cementum of the tooth root. This
is important to note, as the circular fibers are the only type present around the dental
implant [6–8]. The other fiber types are still present around the implant, but upon
encountering the implant surface lacking cementum, they persist in encircling the
implant, functionally becoming circular fibers . Lacking cementum and any
mechanism for proper insertion of the fibers, this leaves the implant more vulnerable to trauma from the oral environment. This also will leave the peri-implant gingiva less stable and more prone to recession.
As the soft tissues mature, the myofibroblasts contract the length of the circular
fibers. This contraction will take place over the weeks following surgery .
Ultimately, what develops is analogous to an O-ring and serves as the only means of
protecting the bone-implant interface. In older flared neck implant designs, the contraction and tightening of the circular fibers moved the “O-ring” apically, taking the
bone and soft tissue with it . This results in the typical bone loss to the first
thread. The reason the bone is lost to the first thread in older implant designs is
likely due to this being the first place on the implant where a tightening O-ring finds
a broad base. In more modern implant designs with abutments that are narrower
than the implant base, the O-ring tightens at that position, generally resulting in
T. R. Schoenbaum and S. Alawie
reduced losses of the bone and soft tissue. Further innovation of this concept is
described in the last chapter.
The circular fiber O-ring must be disturbed as little as possible. As described by
Dr. Abrahamsson’s histological study , repeated (non-traumatic) disturbances of
this area result in significant amounts of bone and soft tissue loss. The effects appear
to be most dramatic in the first months following placement.
latform Switched Implants and the Narrow
At a basic level, the “platform-switched” (PS) implant design is one in which the
abutment is a narrower diameter than the implant at the interface. Most (though not
all) data show that this design maintains peri-implant bone levels better than older
designs [11–16]. This works by a few mechanisms (Fig. 11.3). One, the PS implant
moves the implant-abutment-junction (IAJ) medially, away from the bone. In
nearly every two piece implant ever tested long term, there is a bacterial exudate
External Hex design
platform switch design
Fig. 11.3 On the left side of this diagram, an older, external hex connection implant is represented; while on the right, an internal, conical, platform-switched connection implant is depicted.
The evolution from external hex to the internal conical PS design was brought about in an attempt
to reduce bone loss and screw loosening. This implant has the following advantages: (a) The
implant-abutment-junction (IAJ) is located medially, away from the bone. (b) The head of the
implant acts like a shelf where the circular peri-implant fibers can tighten without slipping down
to the first thread. (c) The connection is generally longer and more robust, resulting in less movement and leakage of the abutment over time. (d) The emergence area of the abutment is narrower,
allowing more room for the bone, peri-implant tissues, and blood supply
11 Emergence Profile of the Implant Abutment and Its Effects
that is pumped out from inside the implant at this junction [14, 17]. Moving the IAJ
away from the bone may lessen the insult on the bone. Two, the PS implant results
in a shelf upon which the gingival fiber O-ring tightens [9, 10]. This is analogous
to the first thread in older implant designs but located more coronally and thus
allows the bone to be maintained at a higher level. Three, many PS implants were
designed in conjunction with more robust connections (compared to the older
external hex designs). Some of these connections have a tapered interface which
seems to increase the rigidity and durability of the IAJ. This is commonly referred
to as a “Morse taper” design, though most implants do not actually have connections that fit any of the 1.5° Morse taper specifications. Nevertheless, the long
internal connections seem to produce less leakage at the IAJ compared to the short
external hex connections [17, 18]. Lastly, the PS implant, by design, has an abutment that is narrower than the implant. The smooth surface of the titanium (or Zr
or Au) abutment is not amenable to bony attachment, so moving this non-integrating surface away from the bone allows the bone to be maintained at a higher position. Conversly, in older style implants the abutment widens directly off the IAJ,
which forces the bone to reestablish at a lower position.
The narrowed abutment concept is an attempt to forgo the dimensions of the
preexisting root and instead create a peri-implant environment that is more suitable
to the unique soft tissue around an implant. PS implants have narrowed abutments
by design, but even some non-PS implants can (and should) have the emergence
area of the abutment narrowed .
The theoretical rational for the narrow abutment is that it allows a greater volume of soft tissue to encircle and protect the implant. This greater volume allows
more room for the initial blood clot to stabilize, allows more room for postoperative swelling, and allows more room for blood supply of the peri-implant tissues
[9, 19]. The above rational is a theory only; we do not yet have the science to
explain precisely why narrowed abutment emergence areas generally preserve the
bone and soft tissue at higher levels. Though the approach may be evolving (see
Chap. 16), currently suggested emergence designs should start narrow out of the
implant and progress through a “wine glass” shape as they approach their widest
dimension at the gingival margin. This design allows the additional subgingival
space for soft tissues and blood supply while providing proper support of the
If a cement-retained crown is to be used, the margins of the abutment should be
placed no deeper than 1 mm subgingival [20, 21] as explained in Chap. 12. If a
screw-retained restoration is to be used, the technician must pay special attention to
the emergence area. It is quite common to see less experienced or less attentive
technicians create restorations that are grossly overcontoured in the emergence area
(Fig. 11.4). This makes delivery of the restoration difficult and may require additional surgical procedures to complete. It also puts extreme pressure on the peri-
implant tissues. In the short term, this pressure causes blanching and is uncomfortable;
in the long term, it results in unnecessary apical migration of the bone and gingiva.
These subtle changes in the emergence shapes can be skillfully used to fine-tune the
position of the soft tissue in the aesthetic zone.