Introduction of dental CAD / CAM system (Cerec 2 system) and application of In Vitro study for recovery of type II sinus

Date: 31/05/2018 / Author: Mr Hiếu

Introduction of dental CAD / CAM system (Cerec 2 system) and application of In Vitro study for restoration of sinus type II (Journal of Thai Society of Orthopedics, Volume 13 - No. 2/2013, General Assembly Vietnam Pharmaceutical Publishing).

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The CAD / CAM auto-recovery system (CAD / CAM) can be restored and attached to an appointment, without having to seal, pour the sample as well as Stage performed in Labo. This is a progressive technology applied in dentistry.

The presentation introduces the CAD / CAM system in dentistry (CEREC 2 system) and the application of in vitro type II salvage. Over 20 inlays have been shown to restore the inlay generated from the CEREC 2 system in line with the modified xoag. Calibra (a composite bivalve composite) proved appropriate for this type of restoration. INTRODUCTION TO THE DENTAL CAD-CAM SYSTEM (CEREC 2) AND IN VITRO STUDY OF MICROLEAKAGE AROUND CLASS II RESTORATION Abstract Dental CAD-CAM system has the major advantage of fabricating and placing restorations in one order, without having to go through conventional steps for prosthesis: impression taking, model casting, laboratoray work ... It is considered as one of the most important applications of computer technologies in dentistry. 

The CAD introduces a dental CAD-CAM system (Cerec 2 system) and its application in Class 2 restorations. In vitro microleakage was assessed on 20 Class II inlays. The results of this study show a good application of the restorations and little microleakage.


The development of computers and automated control techniques is the driving force behind the scientific and technological revolution in modern medicine in general and modern dentistry in particular. CAD / CAM technology is rapidly changing the way dentists practice. Especially thanks to the automatic dental restorative treatment, the treatment can be completed in just one appointment.

The first CEREC 2 facility in Vietnam is a facility for high quality dental rehabilitation centers located in the Department of Odonto-Dentistry, Ho Chi Minh City University of Medicine and Pharmacy. Ho Chi Minh City (Ministry of Health). Wishing to apply new technology, find new possibilities and expand the choice for physicians and patients to achieve high quality restorations and shorten treatment time, we conducted Implementation of this project aims to:

Introduction of dental CAD / CAM system (CEREC 2 system) and application for testing inlay, onlay.

2. In vitro comparison of the gingival margin of the test inlay was carried out using two types of Calibra (composite binary composite) and GC Fuji Plus (modified resin-modified glass ionomer cement).


Introduction of some dental CAD / CAM systems

CAD: is the data collection by optical or mechanical marking by direct marking of prepared teeth or from model (inlay, crown ...) made by a doctor or technician and design the shape recovered from the data collected.

CAM is a fabricated part made of porcelain or metal based fabric that has been designed (either optical or mechanical) or based on a model made by a physician or technician. From there it is possible to summarize the dental CAD / CAM systems in the following table:

CEREC system

The system was developed by Mormann and Brandestini from 1980-1987. Later, it was acquired by Siemens in 1988 and started to market as CEREC 1. CEREC is the most widely used and widely used dental CAD system in the world. The first CEREC inlay was fitted to the patient in 1985.

CEREC 1: CEREC 1 was original (1980-1987), CEREC 1 was second (1988) and COS 2.0 software was developed. 1991, CEREC 1 was introduced in 1992.

CEREC 2: With the experience accumulated during the development stages of CEREC 1, in 1994, the CEREC system was completely redesigned as CEREC 2. This system improved both hardware and software. , can produce many types of recovery such as inlay, onlay, veneer, crowns for the front teeth and the rear teeth [29].

System structure CEREC 2 consists of 3 main components:

Data collection (camera), design recovery (software), fabrication recovery (grinding)

The improved CEREC 2 camera has 12 magnifications compared to the CEREC 1 camera with a magnification of 8. Thus, the image captured by the CEREC 2 camera is more detailed than the image captured by the CEREC 1 camera.

The CEREC 2 machining section can be easily grinded in 6 axes (grinding wheel 2, porcelain clamping unit 1, nose 3). Drills of 1-2mm diameters can be used to grind complex structures such as the degree of protrusion, different altitudes of the wall of the sinus, and can be adjusted to the shoreline of the crown and veneer [28]. Grinders are powered by electric motors so speed is almost unchanged even though grinding at different depths. The grinding time for inlay, onlay and crown varies from 5 to 30 minutes depending on grinding type and size.

The Cos 4.31 software was improved in 1999. Depending on the clinical situation, the chewing surface of the inlay can be designed in a variety of ways, particularly the CEREC 2 system that can create a chewable surface recovery. power.

The most frequently studied problems of the CEREC system

Comparisons of the accuracy of systems [27, 29, 42, 44, 45, 46, 47], restoration materials [14, 21, 22, 40.50], cemented systems [23, 37, 43, 48, 52]

Method of assessing the quality of recovery

Clinical evaluation

Use of X-ray film, scanning electron microscope, US public health standard (life of teeth, bleeding index, restoration quality, color, anatomical shape of teeth and recovery) to assess recovery quality. In addition, complications and complaints of patients were also documented [20, 35, 52]

Vitro evaluation

Recovery strategies are evaluated in two ways:

Invasive tooth tissue: the tooth is cut into thin slices or cut through the center of recovery by slow-speed diamond discs of cooled water, and then visually imaging the reconstructed teeth under the microscope. , forty six]

- Non-invasive dental tissue: the teeth and the restoration are intact, assess the entire recovery area from the microscope or evaluate the thickness of the cement attached to the selected points along the recovery glass. Microelectronics sweep [8, 21, 38].


Study Materials

Conducted research on 20 permanent molars of the human, extracted not due to tooth decay or other loss of substance. The teeth are intact, with the tip.

Create a MO inlay and perform the corresponding inlay with the CEREC system. 2. Divide the two groups into 19 groups: group I inlays with Calibra and group II with Fuju Plus. Attach the inlay to the sinus as directed by the manufacturer.

Research facilities

- CEREC system 2

- Material attached / glued

Group I: Calibra (composite bivalent composite) (Dentsply).

Group II: GC Fuji Plus (resin-modified glass ionomer) (GC).

Research Methods

Study design: In vitro studies follow a random parallel cluster design.

Sinus Inlay: The teeth are fixed on the jaw pattern. The MO inlay sinus cavity with the following standards: 2-3mm deep sinus floor, gingival wall and flat wall, the other side is parallel and perpendicular to the gingival wall. The cylinder is flat, not curved by the external shape of the tooth. No bevels in the city.

Create recovery using the CEREC system

* Collected dental data prepared by camera

The inlay was washed and blown dry, scanned and covered with a thin layer of CEREC powder on the entire sinus and adjacent teeth. Inline sinus scan with camera: The angle of view of the camera coincides with the orientation of the inlay, inlay cavity on the screen to ensure the following four criteria: clear, good contrast, visible clearly, neatly in the middle of the screen. .

* Design recovery

The inlay design routine is executed according to the following on-screen instructions: bottom line drawing, automatic surface line design, side contact, midline drawing, next door

* Grinding recovery

Select the porcelain blocks of appropriate size according to the message on the screen to the grinder. Choosing a grinder, the machine starts the grinding process.

Restored teeth are encoded, heat cycled, insulated, dyed, cut and observed by two independent inspectors. The score scale used to observe and assess the level of penetration of the gums in the gingival tissue of restorations is: 0, 1, 2, 3 (according to Ferrari, 1996) [15].

Use SPSS for Windows 9.01 software to process the results and compare the levels of color penetration between the two groups.



Group I: 8 restoration without color penetration, 2 restoration color penetration to the cylinder (degree 3).

Group II: There are 6 restoration of color penetration not exceeding half the length of the gingival (grade 1), 3 restoration of penetration more than half way to gingival (grade 2) and 1 restoration of color penetration into axis (degree 3).


Statistical analysis

Using the Mann-Whitney Rankings, there was a statistically significant difference (p = 0.014) of the penetration of the pigments in the two groups. Thus, it can be concluded that shore consolidation of the rest of group I is better than that of group II recovery, which is statistically significant (p = 0.014).


Technically CEREC

* Advantages of CEREC system

This study uses the CEREC 2 system as an improved system since 1994. In addition to improvements in hardware such as the camera, grinding parts; The Cos 4.31 software was also improved in 1999. The CEREC 2 system allows for the creation of many types of restorations such as inlay, onlay, crowns, back teeth and veneer laminates. presence of functional chewing [27].

The CEREC 2 system is fully automated, with fewer patient appointments and less recovery time than the classical system [41]. With this technique, the entire process from preparation of the sinus to restoration is done in one appointment, ignoring stages such as sealing, pouring, temporary restoration, as well as phases in the lab.

Another advantage of the CEREC leaf system can be used indirectly.

* The limitations and difficulties of the CEREC system

High initial investment cost. Duration of training is 2 days. Dentists participating in the training must use the camera and evaluate each step of the design [30].

The color of the porcelain blocks is limited, but this problem is easily overcome thanks to the color set of CEREC porcelain system. The sets of color dots allow the color to be unique for each recovery within a 20 minute period.

About the research results

Research results show that CEREC inlay with Calibra is effective in inhibiting microcrystalline formation (80% of good quality - no interference), CEREC InLine cemented with GC Fuji Plus. It is possible to notice that CEREC inlay is of a reliable quality, especially when using sticking / attaching materials. In practice, the CER inlay has a very high conjugation rate and this may yield clinically significant results.

In the 1990s, Mormann's research suggested that the use of composite photosensitive (Heliomoler) to affix the CEREC inlay had good results. The CERC composite inlay with composite bicarbonate had better results than previous generations of composites. Coagulation is easily hardened in areas of the sinus where the polymerization light can not reach.

In the 2001 study, the relative strengths of cement, glass, ionomer, resin-modified glass ionomer, composite bicarbonate on total porosity recovered from CAD / CAM systems, The ionomer is not suitable for fixing porcelain restoration of the CAD / CAM system, the composite binary composite has the best bonding strength [12].

In 1997, in a comparative study of the paste strength of glass ionomer cement and cement resin-modified glass ionomer for porcelain restorations, Vallitu and Fors concluded that the high shear adhesion rate in the glass cement group ionomer, while there was no abrasion in the cement-treated resin-modified glass ionomer cemented group [51].

In 1998, Zueling-Singer-R and Bryant-RW conducted a study of shoreline compliance of inlay remediation made from the CEREC system for three years using composite materials: composite hybrids, granular composite hybrids, ionomer glass cement. The study concluded that the edge of CEREC inlay is highly consistent and stable for 3 years. Composite composite resins have better abrasion resistance than composite hybrids and glass ionomer [52].

The study by Zodiac and Tung Hung (1999) compared the gingival margin of the SONICSYS inlay with the liquid polymer composite and the ionomer glass ionomer hybridization. The study concludes that ceramic composite inlay is significantly better than glass ionomer cement [2].

In an in vitro study using heat-cycling and mechanical stress, Reich and colleagues found that there was a corresponding increase in cemented inlay-composite cement thickness while no correlation was found in CEREC inlay. However, in an in vitro study of the quality of the gingival surface of CEREC type II (1995), two criteria were used: the integrity of the restoration surface (analyzed electronically Before and after heat cycles, mechanical stresses) and the durability of the restoration (observation of color penetration after thermal cycles and mechanical stress), Schmalz et al. affected by the thickness of the material attached.

With the thickness of the material attached to 100 Mm, the failure of sticking / pasting is low from 3% -14%. The thickness of the mounting material is greater than 100 Mm, the offset of the composite is not fully fitted [38].

In summary, it can be seen that the main factor affecting the resurfacing quality is the choice of attaching material, which facilitates close recovery between the restorative and dental tissues. Investigations on a variety of materials, the authors have come to the conclusion that composite bivalves, which are used as the binding material for CEREC recovery, are more effective than hybrid materials and cement ionomer glass.

Practical meaning and clinical application

The CEREC 2 system is an automated system of various types of dental restorations. Many lab and clinical evaluation studies have confirmed the recovery of the CEREC system with good aesthetic and functional results [20, 30, 21, 42]. On the other hand, the porcelain system used in CEREC system, especially Vita Blocs Mark II has many good features: easy to grind, easy to polish, aesthetically pleasing, feldspar frame easy to erase for effective paste, compressive strength Highly abrasion-free and non-eroding teeth.

CEREC 2 was first introduced in Vietnam. Through the research and application of this system in the work of inlay, onlay we realize that this is a modern technique but not complicated. Therefore, if trained, dentists can master the technique, perform high-quality restorations on an appointment with this system.

The study uses two different attachment materials: Calibra composite and GC Fuji Plus cement resin-modified glass ionomer. Results showed that shore reconstitution was good in both groups, especially in Group I with the adhesive material Calibra, with no recovery rate of 80%.

Through research and application of CEREC 2 system, we successfully processed inlay, onlay, and verified the suitable cement type. Therefore, the application of CEREC 2 system to make cosmetic restoration quickly, saving time and labor is a feasible and practical solution.


1. The dental CAD / CAM system marks a new development in modern dental technology.

2. The CEREC 2 system is equipped with the first dental CAD / CAM system in Vietnam that meets the demand for innovative dentistry in Ho Chi Minh City. modern; which stands out with the role of information technology. These systems require users to have basic computer knowledge and skills.

3. In vitro studies on the recovery of type II sinus inlays showed that:

The degree of gingival margin of the inlay embedded in Calibra composite is significantly less than the inlay applied by GC Fuji Plus (p <0.014).

* The choice of attaching / gluing material to the recovery material: Composite composite systems are more suitable for restoration using CAD / CAM systems. CEREC 2 through this in vitro study.

Practical meaning:

Applying CEREC 2 in the form of inlay, onlay in dentistry is a feasible solution that meets the aesthetic and functional requirements and can complete the treatment during an appointment.



Vietnamese documents 
1. Duong Thi Hoai Xuan, Hoang Tu Hung. In vitro evaluation of interstitial bacterial plaque formation in type II sinusoidal direct fillings. Proceedings of scientific research teeth teeth. Ho Chi Minh City University of Medical Sciences 1999: 93-104. 
2. Hoang Dao Bao Tram, Hoang Tu Hung. In vitro evaluation of type II sinus reassortment using SONICSYS. Proceedings of scientific research teeth teeth. University of Medicine, Ho Chi Minh City 1999: 67-75. 
3. Nguyen Thi Kim Yen, Hoan Tu Hung. In vitro evaluation of type II sinus reassortment using SONICSYS. Proceedings of scientific research teeth teeth. Ho Chi Minh City University of Medicine 2001: 98-104.
4. Nguyen Thi Thanh Van, Hoang Tu Hung. Effect of composite sealant on microstructure. Proceedings of scientific research teeth teeth. The University of Medicine, Ho Chi Minh City 1999: 76-92.

English material 
5. Bindl A, Mošrmann W H. Clinical evaluation of adhesively placed Cerec endo-crowns after 2 years - preliminary results. J-Adhes-Dent 1999; 1 (3): 255-65. (Abstract) 
6. Bronwasser PJ, Mošrmann WH, Krejci I, Lutz F. The marginal adaptation of Cerec-Dicor-MGC restorations with dentin adhesives. Schweiz-Monatsschr-Zahnmed 1991; 101 (2): 162-9. 
7. Chen JH, Matsumura H, Atsuta M. Effect of different etching times on the bond strength of a composite resin to a machinable porcelain. J-Dent 1998 Jan; 26 (1): 53-8. (Abstract) 
8. Clotten S, Blunck U, Roulet J F. The influence of a simplified application technique for ceramic inlays on the quality margin. J-Adhes-Dent 1999; 1 (2): 159-66. (Abstract)
9. Coli P. In vitro marginal leaching around Class II resin composite restorations with glass-ceramic inserts. Quintessence Int 1997 Nov; 28 (11): 755-760. 
10. Cvitko E and cs. Effect of martrix systems and polymerization techniques on microleakage of Class II resin coposite restorations. Am J Dent 1992 Dec; 5 (6): 321-323. (Abstract) 
11. Darbyshire PA and cs. Microleakage in Class II composite restoration bond to dentin using thermal and load cycling. J Dent Res 1988 Mar; 67 (3): 585-587. (Abstract) 
12. De Boer HD, Van Waas MAJ, De Gee AJ, Feilzer A J. Bond strength of luting cements to ceramic synthoceram. 79nd session of the IADR 2001-chiba, abtract 1083.
13. Dietschi D and cs. Influence of the restorative technique and new adhesive on the dentine marginal seal and adaptation of resin composite Class II restoration: An in vitro study. Quintessence int 1995; 26: 717-727. 
Estafan D, David A., Calamia J. A new approach to restorative dentistry: fabricatingceramic restorations using CEREC CAD / CAM. Compend-Contin-Educ-Dent 1999 Jun; 20 (6): 555-60. (Abstract) 
15. Ferrari M and cs. Sealing ability of Fuji IX in Class restoration. Am J Dent 1996. 
16. Fisbein S et al. VLC effect of scotchbond and an incremental filling technique on leakage around Class II composite restorations. ASDC J Dent Child 1988 Jan- Feb; 55 (1): 29-33. (Abstract)
17. Fuks va cs. Assessment of marginal leakage around Class II composite restorations in retrieved primary molars. Pediatr Dent 1990 Feb; 12 (1): 24-27. (Abstract) 
18. Godder B. Microleakage reduction using glass - ceramic inserts. Am-J-Dent 1994 Apr; 7 (2): 74-76. 
Hembree J. H. Comparisons of fit of CAD-CAM restorations using three imaging surfaces. Quintessence-Int 1995 Feb; 26 (2): 145-7. (Abstract) 
20. Heymann HO, Bayne SC, Sturdevant JR, Wilder AD, Roberson T M. The clinical performance of CAD-CAM-generated ceramic inlays. JADA 1996 Aug: 
1171-1181. 21. Hurzeler M, Zimmermann E, Mošrmann H. The marginal adaptation of mechanically produced onlays in vitro. Schweiz-Monatsschr-Zahnmed 1990; 100 (6): 715-20.
22. Isenberg BP, Essig ME, Leinfelder K F. Three-year clinical evaluation of CAD / CAM restorations. J-Esthet-Dent 1992 Sep-Oct; 4 (5): 173-6. 
23. Kamada K, Yoshida K, Atsuta M. Effect of ceramic surface treatments on the bonding of four resin luting agents to a ceramic material. J-Prosthet-Dent 1998 May; 79 (5): 508-13. (Abstract) 
24. Kawai K, Hayashi M, Torii M, Tsuchitani Y. Marginal adaptability and fit of ceramic milled inlays. JADA 1995 Oct: 1414 - 1419. 
25. Ko Y M. The marginal leakage of resin inlay according to different method in class II cavity restoration. J Dent Res 1993; 72 (4) (Abstracts) 
26. Liberman R. and cs. Reduction of microleakage in Class II composite resin restorations using retentive pins. J Oral Rehabil 1996 apr; 23 (4): 240-243.
27. Liu PR, Isenberg BP, Leinfelder K. F. Evaluating CAD-CAM generated ceramic veneers. JADA 1993 Apr: 59 - 63. 
28. Mehl A, Hickel R. Curent State of Development and Perspective of Machine-Based Production Methods for Dental Restoration. Int-J-Computerized Dentistry 1999 Jan; 1 (2): 9-36 
29. Mošrmann WH, Schug J. Grinding precision and accuracy of CEREC 2 CAD-CIM inlays. JADA 1997 Jan: 47 - 53. 
30. Mošrmann WH, Brandestini M, Lutz F, Barbakov F, Gotsch T. CAD-CAM ceramic inlays and onlays: a case report after 3 years in place. JADA 1990 May: 517 - 520. 
31. Nathanson D, Riis DN, Cataldo GL, Ashayeri N. CAD-CAM ceramic inlays and onlays: using an indirect technique. JADA 1994 Apr: 421 - 427.
32. Neumann P. CAD / CAM ceramics. Int-J-Computerized Dentistry 1999 Jan; 1 (2): 45-57 
33. Prati C. Early marginal microleakage in Class II resin composite restoration. Dent Mater 1989 Nov; 5 (6): 392-398. (Abstract) 
34. Rekow ED. Dental CAD-CAM systems What is the state of the art? JADA 1991 Dec: 43 - 48 
35. Reiss B, Walther W. Clinical Long-Term Results and 10 Years Kaplan-Meier-analysis of Cerec restoration. Int-J-computerized dentistry 2000 Jan; 1 (3): 9-24. 
36. Rosenblum MA, Schulman A. A review of all-ceramic restorations. JADA 1997 Mar; 297 - 307. 
37. Sato K, Matsumura H, Atsuta M. Effect of three-liquid bonding agents on bond strength to a machine-milled ceramic material. J-Oral-Rehabil 1999 Jul; 26 (7): 570-4. (Abstract)
38. Schmalz G, Federlin M, Reich E. Effect of dimension of luting space and composite luting on marginal adaptation of a class II ceramic inlay. J-Prosthet-Dent. 1995 Apr; 73 (4): 392-9. 
39. Schneider W. Cerec 3. Int-J-computerized dentistry 2000 Jan; 1 (3): 33-40. 
40. Shearer AC, Heymann HO, Wilson H. H. Two ceramic materials compared to the production of CEREC inlays. J-Dent 1993 Oct; 21 (5): 302-4. 
41. Siervo S, Pampalone A, Valenti G, Bandettini B, Siervo R. Porcelain CAD-CAM veneers some new uses explored. JADA 1992 Apr: 63 - 67. 
42. Sjogren G. Marginal and internal fit of four different types of ceramic inlays after luting. An in vitro study. Acta-Odontol-Scand 1995 Feb; 53 (1): 24-8.
43. Sjogren G, Molin M, van Dijken-J, Bergman M. Ceramic inlays (Cerec) cemented with either a cured or a chemically cured composite resin luting agent. A 2-year clinical study. Acta-Odontol-Scand 1995 Oct; 53 (5): 325-30. (Abstract) 
44. Sturdevant JR, Bayne SC, Heymann H O. Margin gap of ceramic inlays using second-generation CAD / CAM equipment. J-Esthet-Dent 1999; 11 (4): 206-14. (Abstract) 
45. Thordrup M, Isidor F, Horsted B P. A one-year clinical study of indirect and direct composite and ceramic inlays. Scand-J-Dent-Res 1994 Jun; 102 (3): 186-92. (Abstract) 
46. ​​Thordrup M, Isidor F, Horsted B P. Comparison of marginal fit and microleakage of ceramic and composite inlays: an in vitro study. J-Dent 1994 Jun; 22 (3): 147-53.
47. Thordrup M, Isidor F, Horsted B P. A 3-year study of inlays milled from machinable ceramic blocks representing 2 different inlay systems. Quintessence-Int 1999 Dec; 30 (12): 829-36. Abstract (English) 
48. Torii Y, Itou K, Itota T, Hama K, Konishi N, Nagamine M, Inoue K. Influence of filler content and gap dimensions on wear resistance of resin composite luting in CAD / CAM ceramic inlay restoration. Dent-Mater-J 1999 Dec; 18 (4): 453-61. (Abstract) 
49. Van-Dijken JW, Ormin A, Olofsson A L. Clinical performance of pressed ceramic inlays with resin-modified glass ionomer and autopolymerizing resin composite cements. J-Prosthet-Dent 1999 Nov; 82 (5): 529-35. (Abstract)
50. Van Meerbeek B, Inokoshi S, Willems G, Noack MJ, Braem M, Lambrechts P, Roulet JF, Vanherle G. Marginal adaptation of four tooth-colored inlay systems in vivo. J-Dent 1992 Feb; 20 (1): 18-26. (Abstract) 
51. Vallittu PK, Forss H. A study of bonding glass polyalkenoate cement to the surface of a dental ceramic material. Int-Dent-J 1997 Feb; 47 (1): 53-8 
52. Zuellig-Singer R, R W. Bryant Three-year evaluation of computer-machined ceramic inlays: Influence of Luting agents. Quintessence-Int 1998 Sep; 29 (9): 573-82. (Abstract) 
53. Yap AU and cs. An in vitro microleakage study of three restorative techniques for Class II restorations in posterior teeth. Biomaterials 1996 Nov; 17 (21): 2031-2035.


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