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······························································································· iii
1. ···················································································· 4
. ············································································· 4
. ················································································ 9
2. ································································· 10
. ······························································································ 13
. ······························································································ 17
impression technique ·················································· 7
Figure 4. Screen shots of 3D reconstructed model from iTero
digital impression ······················································· 8
Figure 5. Example of the definitive cast using digital impression
technique ··································································· 8
definitive casts ··························································12
model ·······································································11
impression and definitive casts fabrication technique ·····11
iii


.
, 1, 2 6,
6mm
.

. iTero system
.


. t-
.
.
iv
.
3. iTero system
.
: , ,
1
< : >

,
.2
,

2


.4-12
CAD/CAM
.13 Electronic impression device(EID)

computer aided manufacturing
system(CAM) .14


.15
iTero system(Cadent Inc., Carlstadt, New
Jersey, USA) .14 iTero system (parallel
confocal) , (triangulation
sampling) CEREC system
.16 14 x 18 mm2
10
. (telecentric)

3

. milling machine
.

.2, 4-9, 17, 18


.


.
1.
.
, 1 , 2
(Warantec, Seoul, Korea) (Figure 1).
shoulder , 6mm, 6
. 1 5mm, 2 6mm .
Fig 1. Modified typodont master model and abutments. (A: Frontal view
of master model, B: Dimensions of abutments)
A B
(LPM), 1 2 (RPM), 2
1 (XA1), 2 1
(XA2) .
Fig 2. Occlusal reference points of master model. Same points were used
to measure on definitive casts.
6
Company, Skokie, Illinois, USA)
. (V.P.S. Tray Adhesive, Kerr, California,
USA) 15
(Aquasil Ultra XLV, Dentsply Caulk, Milford, Delaware, USA)
. (Fuji-Rock RP, GC International,
Scottsdale, Arizona, USA) 100g 20ml
. 24
(Figure 3). 10
10 .
Fig 3. Example of the definitive cast using conventional impression
technique.
USA) .
iTero , , , , 5
2
. 3

. iTero center CAD
(Figure 4). STL file
iTero computer numerical control milling machine(VF-2TR,
8
10 .
Fig 4. Screen shots of 3D reconstructed model from iTero digital
impression. The data files undergo a modeling process and finishing
margin determination.
Fig 5. Example of the definitive cast using digital impression technique.
B
9
(CD-10CPX 500-180-20, Mitutoyo, Tokyo, Japan)
.
0.01.
10
. 3 .
.
.
(SAS 9.2 ver, SAS Institute Inc, Cary,
North Carolina, USA) 95% t-
.
10
(Table 1).
(Table 2).
11
Table 1. Means and SDs of measured distance() of master model
PP MM LPM RPM XA1 XA2
Mean 29.62 49.84 30.57 30.83 48.89 49.34
(SD) (0.01) (0.00) (0.01) (0.01) (0.01) (0.01)
ME% 0.03 0 0.03 0.03 0.02 0.02
ME means coefficients of variability (percent errors)
Table 2. Mean distance(SDs) of definitive casts according to impression
and definitive casts fabrication technique (n=10)
Distance () PP MM LPM RPM XA1 XA2
Conventional 29.63
Fig 6. Differences() in dimensions between master model and definitive
casts.

.

.

.

vinyl polysiloxane
.12, 17, 19, 20
,4


.21 Kang 11 Johnson 19
.

.17
.
14
0 ~ 0.04
,
. Ender Mehi22


. Ender Cerec
AC Bluecam Lava COS system
.
stereolithography .
iTero system
100,000
.

, 13.5 focal depth . iTero system
15 16

.
.
milling machine 2
15
.16

.
,23
24 25
. Tjan 26 90
.
, 100 ~ 150
.27
. Vigolo 28
34
. Kwon 29

81
.

.
.


16
.

.
17
.
.
1.
.
2. iTero system
.
3. iTero system
.
18

1. Luthardt RG, Walter MH, Weber A, Koch R, Rudolph H. Clinical
parameters influencing the accuracy of 1- and 2-stage
impressions: a randomized controlled trial. The international
journal of prosthodontics 2008;21(4):322-27.
2. Linke BA, Nicholls JI, Faucher RR. Distortion analysis of stone
casts made from impression materials. The journal of prosthetic
dentistry 1985;54(6):794-802.
3. Carrotte PV, Johnson A, Winstanley RB. The influence of the
impression tray on the accuracy of impressions for crown and
bridge work--an investigation and review. British dental journal
1998;185(11-12):580-85.
4. Ceyhan JA, Johnson GH, Lepe X. The effect of tray selection,
viscosity of impression material, and sequence of pour on the
accuracy of dies made from dual-arch impressions. The journal of
prosthetic dentistry 2003;90(2):143-49.
5. Dounis KS, Dounis G, Ditmyer M, Ziebert GJ. Accuracy of
successive casts for full-arch fixed prostheses. The international
journal of prosthodontics 2010;23(5):446-49.
6. Damodara EK, Litaker MS, Rahemtulla F, McCracken MS. A
randomized clinical trial to compare diagnostic casts made using
plastic and metal trays. The journal of prosthetic dentistry
2010;104(6):364-71.
7. Breeding LC, Dixon DL. Accuracy of casts generated from dual-
arch impressions. The journal of prosthetic dentistry
2000;84(4):403-07.
19
8. Hoyos A, Soderholm K. Influence of tray rigidity and impression
technique on accuracy of polyvinyl siloxane impressions. The
international journal of prosthodontics 2011;24(1):49-54.
9. Caputi S, Varvara G. Dimensional accuracy of resultant casts made
by a monophase, one-step and two-step, and a novel two-step
putty/light-body impression technique: an in vitro study. The
journal of prosthetic dentistry 2008;99(4):274-81.
10. Chandran DT, Jagger DC, Jagger RG, Barbour ME. Two- and
three-dimensional accuracy of dental impression materials:
effects of storage time and moisture contamination. Bio-medical
materials and engineering 2010;20(5):243-49.
11. Kang AH, Johnson GH, Lepe X, Wataha JC. Accuracy of a
reformulated fast-set vinyl polysiloxane impression material
using dual-arch trays. The journal of prosthetic dentistry
2009;101(5):332-41.
12. Johnson GH, Chellis KD, Gordon GE, Lepe X. Dimensional stability
and detail reproduction of irreversible hydrocolloid and
elastomeric impressions disinfected by immersion. The journal of
prosthetic dentistry 1998;79(4):446-53.
13. Kachalia PR, Geissberger MJ. Dentistry a la carte: in-office
CAD/CAM technology. Journal of the California dental association
2010;38(5):323-30.
14. Garg AK. Cadent iTero's digital system for dental impressions:
the end of trays and putty? Dental implantology update
2008;19(1):1-4.
conventional, digital or digital plus in-office milling. The journal of
the american dental association 2009;140(10):1301-04.
20
16. Henkel GL. A comparison of fixed prostheses generated from
conventional vs digitally scanned dental impressions. Compendium
of continuing education in dentistry 2007;28(8):422-4, 26.
17. Stober T, Johnson GH, Schmitter M. Accuracy of the newly
formulated vinyl siloxanether elastomeric impression material.
The journal of prosthetic dentistry 2010;103(4):228-39.
18. Supowitz ML, Schnell RJ, Dykema RW, Goodacre CJ. Dimensional
accuracy of combined reversible and irreversible hydrocolloid
impression materials. The journal of prosthetic dentistry
1988;59(4):404-09.
19. Wadhwani CP, Johnson GH, Lepe X, Raigrodski AJ. Accuracy of
newly formulated fast-setting elastomeric impression materials.
The journal of prosthetic dentistry 2005;93(6):530-39.
20. Lepe X, Johnson GH. Accuracy of polyether and addition silicone
after long-term immersion disinfection. The journal of prosthetic
dentistry 1997;78(3):245-49.
21. Johnson GH, Craig RG. Accuracy of four types of rubber
impression materials compared with time of pour and a repeat
pour of models. The journal of prosthetic dentistry
1985;53(4):484-90.
22. Ender A, Mehl A. Full arch scans: conventional versus digital
impressions--an in-vitro study. International journal of
computerized dentistry 2011;14(1):11-21.
23. Hellie CM, Charbeneau GT, Craig RG, Brandau HE. Quantitative
evaluation of proximal tooth movement effected by wedging: a pilot
study. The journal of prosthetic dentistry 1985;53(3):335-41.
24. Gates GN, Nicholls JI. Evaluation of mandibular arch width change.
The journal of prosthetic dentistry 1981;46(4):385-92.
21
25. Grajower R, Zuberi Y, Lewinstein I. Improving the fit of crowns
with die spacers. The journal of prosthetic dentistry
1989;61(5):555-63.
26. Tjan AH, Whang SB. Comparing effects of tray treatment on the
accuracy of dies. The journal of prosthetic dentistry
1987;58(2):175-78.
27. Att W, Komine F, Gerds T, Strub JR. Marginal adaptation of three
different zirconium dioxide three-unit fixed dental prostheses.
The journal of prosthetic dentistry 2009;101(4):239-47.
28. Vigolo P, Fonzi F, Majzoub Z, Cordioli G. An evaluation of
impression techniques for multiple internal connection implant
prostheses. The journal of prosthetic dentistry 2004;92(5):470-
76.
29. Kwon J, Son Y, Han C, Kim S. Accuracy of implant impressions
without impression copings: a three-dimensional analysis. The
journal of prosthetic dentistry 2011;105(6):367-73.
22
Abstract
and conventional impression technique
(Directed by professor Chong Hyun Han, DDS, MSD, PhD)
Purpose : The purpose of this study was to evaluate and compare the
dimensional accuracy of definitive casts that are fabricated from digital
impression system and conventional impression technique.
Materials and methods : Impressions were made from a modified dentoform
master model containing standard abutments. Dimensional changes()
between the master model and definitive casts were assessed. Ten
23
impressions were made with either vinyl polysiloxane impression material or
digital impression system. The conventional impression was cast in
improved dental stone. Working casts for digital impression system were
fabricated by milling polyurethane block. Measurements of the master model
and definitive casts, including anteroposterior and cross-arch dimensions,
were made with digital calipers. The data were analyzed by independent t-
test(p<.05).
Results : The definitive casts obtained with conventional impression
technique had significantly larger dimensions as compared to those of the
master model. Differences between the digital impression working model and
the master model were not significant.
Conclusions : The digital impression system demonstrated acceptable
accuracy for clinical use , since the results for digital impression system
were comparable to the results for vinyl polysiloxane materials, and the
differences as compared to the master model were small.
Key words : digital impression system, definitive cast , accuracy of
impression technique