A systematic review on the accuracy of zirconia crowns and fixed dental prostheses

Figures & data

Figure 1. Search strategy of the systematic review. 841 articles were found and 767 were excluded after screening of title and abstract. After full-text analysis another 60 articles were excluded which left 14 articles to be included.

Table 1. Overview of the included studies and their setting parameters and results.

	Settings						Marginal gap			Internal gap			Total gap
Author	Impression	Abutment tooth	Units	Evaluation	Pre-set spacer	N	Fit	SD	Acc	Fit	SD	Acc	Fit	SD	Acc
Cetik et al. [24]	Conv	M	SC	CS	45 (1)–85	10	73	17	28	80	20	5	78	19	7
	Dig	M	SC	CS	45 (1)–85	10	63	14	18	70	15	14	69	15	16
Cunali et al. [43]	Dig*	M	SC	SR	20–70	10	78	12	58	145	36	75	128	30	58
	Dig	M	SC	SR	20–70	10	78	16	58	134	34	64	120	29	50
	Dig	M	SC	MCT	20–70	10	69	9	49	106	16	36	97	14	27
	Dig	M	SC	MCT	20–70	10	75	7	55	110	13	40	101	11	31
Dahl et al. [36]	Dig	INC	SC	3D	30 (0.5)–70	3				135	127	65	78	65	8
	Dig	INC	SC	3D	15 (0.5)–50	3				126	92	76	81	56	31
Kocaagaoglu et al. [25]	Conv	PM	SC	SR	0 (1)–30	10	86	12	86	131	17	101	116	15	86
	Dig	PM	SC	SR	0 (1)–30	10	59	20	59	127	27	97	104	25	74
	Dig	PM	SC	SR	0 (1)–30	10	48	7	48	101	13	71	83	11	53
Miura et al. [44]	Conv	M	SC	SR	0 (1)–30	5				85	29	55
Nelson et al. [45]	Conv	PM	SC	CS	0 (1)–40	10	118	5	118	80	4	40	99	4	59
Pedroche et al. [26]	Conv	M	SC	SR	10–60	10	87	31	77	238	31	182	201	36	155
	Dig	M	SC	SR	10–60	10	59	14	49	112	33	55	95	28	53
Lee et al. [46]	Conv	INC	SC	SR	40–40	10	86	32	46	86	26	46	85	28	45
	Conv	INC-INC	4-unit	SR	40–40	10	66	24	26	124	41	84	110	37	70
	Conv	CAN-CAN	6-unit	SR	40–40	10	90	44	50	145	62	105	131	58	91
Almeida e Silva et al. [27]	Conv	PM-M	4-unit	SR	0 (0.8)–30	12	65	37	65	66	42	36	66	40	51
	Dig	PM-M	4-unit	SR	0 (0.8)–30	12	64	37	64	59	36	29	61	36	46
Dahl et al. [47]	Dig	PM-M	3-unit	3D	30 (0.5)–70	3							105	71	35
	Dig	PM-M	3-unit	3D	15 (0.5)–50	3							96	55	46
Keul et al. [9]	Conv	PM-M	4-unit	SR	30 (1.5)–60	12	141	193	111	166	138	106	160		100
	Dig	PM-M	4-unit	SR	30 (1.5)–60	12	127	67	87	154	60	94	147		87
Memarian et al. [48]	Dig*	PM-M	3-unit	CS	35–35	12	113	20	78	68	12	33	83	14	48
	Dig	PM-M	3-unit	CS	35–35	12	106	19	71	73	20	38	84	20	49
	Dig	PM-M	3-unit	CS	35–35	12	117	19	82	80	15	45	92	16	57
Su & Sun [29]	Conv	CAN-PM	3-unit	SR	40–60	10	76	18	36	134	47	74	105	36	45
	Dig	CAN-PM	3-unit	SR	40–60	10	63	16	23	110	40	50	87	28	27
Ueda et al. [28]	Conv	PM-M	4-unit	SR	30 (1.5)–60	12	87	60	57	97	51	47	95	51	49
	Dig	PM-M	4-unit	SR	30 (1.5)–60	12	63	42	33	68	33	18	67	35	22

The results for marginal, internal and total gap are mean values in μm. Pre-set spacer: setting used in CAD software for cement spacer in μm; N: number of test specimens; SD: standard deviation; Acc: accuracy; Conv: conventional impression; Dig: digital impression; M: molar; INC: incisive; PM: premolar; CAN: canine; SC: single crown; CS: cement section technique; SR: silicone replica technique; MCT: micro-CT; 3D: 3D scan technique. *Scanned master.

Table 2. Overview of the intraoral scanners (IOS), laboratory scanners, CAM systems, and zirconia materials used in the included studies.

IOS system	Scanner/CAD system	CAM system	Zirconia material
3M Lava COS [27,28]	3M Lava [27,28]	3M Lava CNC 500 [27,28]	3M Lava Zirconia [28]
3Shape TRIOS [24–26,29,36,47]	3Shape D700 [26,48]	Ceramill Motion 2 [24,48]	Ceramill Zi [43,45,48]
Cerec Omnicam [25]	3Shape D800 [29]	Cercon Brain expert [44,48]	Cercon ZR [44,48]
iTero [9]	3Shape N/S [24]	Cerec MC XL [25]	Denzir [36,47]
N/S [46]	Ceramill MAP400 [43,48]	DMG Mori Ultrasonic 20 linear [26]	DD Bio ZW 3Y-TZP [36,47]
	Cercon Eye [44]	Imes iCore Coritec 250i [25]	InCoris [43]
	Cerec inEOS X5 [25]	Straumann milling [9]	Metoxit Zirkonia [26]
	Cerec inLab [43]	VHF 450 classic [45]	Straumann Zerion [9]
	Dental Wings [25,45]	Zirkonzahn M2 [48]	Upcera [29]
	Straumann Cares 2 [9]	N/S [29,36,43,46,47]	Zirkonzahn Prettau Zr [48]
	Zirkonzahn S600 Arti [48]		Zirkonzahn ICE Zirkon HT [25]
	N/S [36,46,47]		N/S [24,27,46]

N/S: not specified.

Table 3. Fit and accuracy of the zirconia restorations in μm, for marginal, internal, and total gap.

	N	Mean	SD	Min	Max
Marginal gap
Fit	26	83	24	48	141
Accuracy	26	59	25	18	118
Internal gap
Fit	29	111	39	59	238
Accuracy	29	61	36	5	182
Total gap
Fit	30	101	30	61	201
Accuracy	30	53	30	7	155

N: number of test results; SD: standard deviation.

Table 4. Fit and accuracy of zirconia restorations in μm, for marginal, internal, and total gap according to impression technique.

	Impression
	N	Mean	SD
Marginal gap
Conv fit	11	89	23
Conv accuracy	11	64	32
Dig fit	15	79	25
Dig accuracy	15	55	20
Internal gap
Conv fit	12	119	49
Conv accuracy	12	73	46
Dig fit	17	104	30
Dig accuracy	17	53	25
Total gap
Conv fit	11	113	39
Conv accuracy	11	69	39
Dig fit	19	94	21
Dig accuracy	19	43	20

N: number of test results; SD: standard deviation; Conv: conventional impression; Dig: digital impression.

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