This document provides information on ready-made primary anterior zirconia crowns called ZIRKIZ crowns. It discusses that zirconia crowns are esthetic, strong and do not require dental impressions. The document reviews the physical and chemical properties of zirconia and its biocompatibility. It describes how zirconia favors gingival integration and outlines the advantages, indications, preparation, cementation and shape adjustment of ZIRKIZ crowns. Case presentations show examples of using the crowns to correct dental issues like crossbite in primary teeth.

1. Ready-made primary anterior
crowns(ZIRKIZ® crowns)
Dr. Sung-Ki Kim
(Developer of ZIRKIZ ®
crowns, South Korea)

2. Requirements
• Durable
• Retentive
• Esthetic

6. Ready-made zirconia crowns
• Esthetic
• Strength
• No need for
impression

7. Zirconia?
• Physical property : close to metal
• Color : tooth-like
• “ceramic steel”

8. • Thermostable
• Low heat conductivity
• Stable chemical resistance
• Low thermal expansion
• High strength, hardness, abrasion
resistance

9. C.S(㎫) T.S(㎫)
Composite resin 70~80 30~50
Amalgam 300~500 45~60
GI 93~226 -
Porcelain 150~600 30~60
ZPC 100~160 3~8
ZOE 2~14 -
Ni-Cr - 400~1000
Enamel 270~400 -
Dentin 230~300 40~50
ZIRCONIA 2000 900~1200

10. Physical and chemical properties
Requirement for
Property Unit ZIRKIZ Value
ISO 13356
Bulk density g/cm3 6.068~6.090 ≥ 6.00
Chemical Composition
ZrO2 + HfO2 + Y2O3 99.60 > 99.0
Y2O3 percent mass 5.35 4.5 to 5.4
HfO2 fraction 3.00 ≤5
Al2O3 0.21 < 0.5
Other oxides* 0.19 < 0.5
Microstructure :
- Mean linear intercept distance ㎛ 0.25 ± 0.05 ≤ 0.4
Maximum amount of monoclinic phase :
- before accelerated aging % 8.12 ≤ 20
- after accelerated aging 15.82 ≤ 25
Biaxial flexure Strength :
- before accelerated aging MPa 1200 ≥ 500
- after accelerated aging 1140 ≥ 500(Decrease not more than 20%)
Radioactivity Bq/kg 2.2 ≤ 200

11. Biocompatibility
Property Standard ZIRKIZ Value
Cytotoxicity ISO 10993-5 Noncytotoxic
Acute Systemic Toxicity ISO 10993-11 Do not show any systemic toxicity potential.
Oral Mucosa Irritation Do not possess any oral mucosa irritation potential.
ISO 10993-10
Delayed Type Hypersensitivity Do not possess any delayed hypersensitivity.
ISO 10993-10

12. Soft tissue adaptation by
Zirconia
• A Material That Favors Gingival
Integration
1. Coronary repositioning
2. Papillary reconstruction
3. Scalloped gum
=> Reduced Bacterial Adhesion

13. Historical Input
• Characteristics of Epithelial tissue
• Characteristics of Connective tissue
• Welander et al.(2008)

14. Characteristics of Epithelial tissue
• Epithelial cells : proliferation
• Connect to Zirconia via a basal lamina and
hemidesmosomes connections
• Begin 2nd day after operation
• Continue to the apical pole(of the basal
lamina) until they cover zirconia to 2mm

15. • The newly formed epithelium has all of the
historical characteristics of a normal tooth

16. Characteristics of Connective
tissue
• Proportion : collagen fiber > fibroblast
• Collagen fiber
– major component of the extracellular matrix
– forms essential framework
– influences the direction of fibroblasts’ growth

18. 5.47
52 51 61 62

23. • Size : #1, #2, #3, #4
• Shade : original shade(A1), PW(Pedo-
White)

24. Starter kit

25. Refill kit

27. Laser markig(indeliable)

28. Should be handled by pincette

29. Advantages
• Esthetics in addition to strength
• Without metal
• Luting available
• Contouring available
• Without facing
• Thin labial structure resembles natural
primary anterior tooth(gingival tissue
adaptation)

30. • Chair-time decreased
• Bleeding decreased
• Repair available
• 1-visit (sedation) : no impression
• No metal appearance at gingival margin
• Occlusal adjustment available

31. Indications
• Every cases which needs full coverage in
primary anterior teeth
• Proximal caries in primary anterior teeth
• In case of crowns for primary central
incisor only
• Correction of dental crossbite

32. Every cases which needs full coverage in primary anterior teeth

33. Proximal caries

34. Primary central incisor only

35. Correction of dental crossbite

36. Preparation
• Incisal edge
– 2mm reduction
• Proximal surface
– Fit to selected size

37. • Labiopalatal surface
– The best important part for retention
– “Passive fit”
– Amount of reduction : approximately 15~20%
– At least 2mm subgingivally for the adaptation
with gingiva
– Avoid too much reduction not to be less
retentive

38. • Reduction of incisal tip

39. • Reduction of proximal surface

40. • Reduction of labial surface

41. • Reduction of palatal surface

42. • Reduction completed

43. Cementation
Full-coverage zirconia-based
restorations with adequate
retention do not require resin
bonding for definitive
cementation

44. Resin bonding, however, may
be advantageous in certain
clinical situations and is a
necessity for bonded
restorations

45. • Cementation for primary anterior zirconia crowns
– No need of strong adhesive strength like permanent
tooth
– bleeding
– passive fit : hard to hold crowns at proper position
Recommendation : Light-
curing resin cement(or GIC)

46. Shape adjustment
• Shape adjustment with high-speed diamond bur
• Adjustable after setting of crowns as well as
outside of oral cavity
• Using finishing & polishing kit for porcelain in order
• Should be used with water-cooling when using
high or low-speed bur

52. -If you grind ZIRKIZ crowns under the red line too much, it can be fractured
because the cervical margin is really thin.

53. Recommended grinding area and the amount
- area : incisal to the red line
- amount
#A ½
proximal : max. 0.2mm
incisal : max. 0.4mm
- area : incisal to the red line
- amount
#B proximal : max. 0.2mm
½
incisal : max. 0.4mm
Thickness at the red line( ): 0.5~0.6mm

54. Case Presentation

55. 2010.6.10

56. After treatment

58. 2010.9.6

59. 2010.11.11

60. 2011.4.16

62. 2011.2.11 Park KB Pre-treatment

64. After treatment, crossbite corrected

65. 3 months later

66. 6 months later

67. 7 months later

69. 2010.11.22 Kim JY Pre-treatment

70. After treatment

71. 1 month later