|Year : 2016 | Volume
| Issue : 2 | Page : 53-55
Is a three-dimensional-printed tooth filling possible?
Muhammet Kerim Ayar
Department of Restorative Dentistry, Istanbul Biruni University, Istanbul, Turkey
|Date of Web Publication||9-Jun-2016|
Muhammet Kerim Ayar
Department of Restorative Dentistry, Faculty of Dentistry, Istanbul Biruni University, Istanbul
Source of Support: None, Conflict of Interest: None
Introduction: Three-dimensional (3-D) printing is seen as an innovative production process in many fields of dentistry and medicine. But implantation of this novel production process into the treatment of decayed teeth in dentistry remains lacking. Destruction of dental tissues as a result of dental caries is generally treated with dental resin composite fillings. However, a 3-D-printed tooth filling approach, which could be an alternative to traditional approaches, has a potential to reduce treatment costs and technique-sensitivity of the placement of restorative material. The Hypothesis: Here, the hypothesis that a 3-D-printed tooth filling approach could be an alternative to traditional approaches to treatment of decayed teeth is proposed. Evaluation of the Hypothesis: The actual implementation of the 3-D-printed tooth filling technique in the practice of restorative dentistry was discussed in this manuscript.
Keywords: Three-dimensional (3-D)-printing, dental filling, dental caries
|How to cite this article:|
Ayar MK. Is a three-dimensional-printed tooth filling possible?. Dent Hypotheses 2016;7:53-5
| Introduction|| |
Dental caries is a process or a chronic pathology that advances at a very low speed. The pathology rarely limits by itself and, in the lack of treatment, hard tissue destruction as a result of caries process advances as far as the tooth is ruined.  The symptom of the disease is the damage of the hard tissue of the teeth. Recent restorative therapy of dental caries was based on the replacement of the caries tissue with restorative materials, such as composite resin. Dentists can place restorative materials on the prepared cavity directly or indirectly by placing restoration that is prepared under laboratory conditions.  Both methods have advantages or disadvantages depending on a number of conditions including the size of the prepared cavity, selection of material, operation time, and visit frequency. , Direct placement of restorative materials takes less time to be performed but its indication is limited with smaller to medium sizes of cavities. Large cavities with cusp replacements need to be restored with indirect restorations to ensure long-term survival of restoration, and this requires more time, cost, and visit frequency. On the other hand, when the cavity size and configuration gets into complex, the direct restoration of cavity becomes more technique-sensitive and hence, requires more time.  However, clinical success of current restorative materials is not fine, as dental patients in the United States spend over US $20 billion annually to replace failed resin composite restorations. 
| The Hypothesis|| |
A three-dimensional (3-D)-printed tooth filling approach has a potential to reduce treatment costs and technique-sensitivity of the placement of restorative material. 3-D printing of medical materials is a novel approach and implanting this technology in restorative dentistry practice should provide benefits for both patients and dentists.
A 3-D-printed tooth filling approach to treat a cavitated tooth lesion will involve four steps:
- Preparation of tooth according to cavity preparation principles of onlay/inlay restorations,
- Acquiring of optical images of prepared cavity and 3-D design of restoration,
- Printing a filling with proper material with a 3-D printer, and
- Cementation of a 3-D-printed filling into the cavity with resin adhesive systems.
| Evaluation of the Hypothesis|| |
Although, printing tooth fillings with 3-D technology may be a novel way for state and art of dentistry, mechanical properties, and adhesion capabilities with the tooth structures of the printing material should be similar to those of contemporary dental filling materials in order to achieve a similar clinical success. Most of the current filling materials are based on methacrylate chemistry.  They commonly use commonly methacrylate monomers such as bisphenol A-glycidyl methacrylate (Bis-GMA) or Ultra Direct Memory Access (UDMA). Currently, it has reported that 3-D-printable antimicrobial composite resins were investigated.  These printing materials are not loaded with glass fillers that provide strength to the material. So that, it may expected that mechanical properties of these novel 3-D-printable composite resins would be inferior when compared with those of contemporary resin composite materials.  However, it is possible to reinforce printing materials with the addition of a range of fillers. Therefore, it is possible to see 3-D-printable composite resins with enhanced mechanical properties on the market in the next years.
Another clinical question is about the adhesion compatibility of the 3-D-printable composite resins with current resin-based adhesive systems when bonded to enamel and dentin. To the best knowledge of the author, there are no published studies that asses the bond strength of 3-D-printable composite resins to enamel and dentin. Laboratory and clinical studies will aid in addressing this question. However, it should be mentioned that available 3-D-printable composite resins are based on the methacrylate chemistry, so that they may additionally present good bond strength and can be an appropriate choice with the use of current resin-based adhesive systems. Thus, if 3-D-printable composite resins could be compatible with current adhesive resins and could have predictable mechanical properties, 3-D-printed tooth filling approach might be used for restoration of the decayed teeth.
As 3-D-printed tooth filling will be prepared with the use of 3-D printer on the desk, this approach could seem similar to indirect tooth restorations, especially computer-aided design and computer-aided manufacturing (CAD/CAM) milling restorations. Along with that, the price of 3-D-printer and materials could be lower than those of CAD/CAM systems, dentists additionally will print other objects such as custom made trays for office-bleaching cases or even surgical guides for dental implant surgery. Certainly, the implementation of 3-D printing technology into restorative dentistry is not limited with 3-D-printed tooth filling. 
| Conclusion|| |
It seems that it is currently possible to restore a decayed teeth with the use of 3-D-printing technology if 3-D-printable composite resins with superior mechanical properties and appropriate adhesion properties develop. Although, the knowledge in the literature supporting hypothesis that presented in this manuscript have been gathering for a while, the actual implementation of the 3-D printed tooth filling technique defined in this manuscript would represent an important novelty in the practice of restorative dentistry.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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