*Juliusz Kosewski, Agnieszka Mielczarek
Influence of composite modeling resin application technique on resin quantity and structure
Wpływ techniki aplikacji żywicy modelującej warstwy kompozytu na jej ilość i strukturę
Department of Conservative Dentistry, Medical University of Warsaw, Poland
Head of Department: Professor Agnieszka Mielczarek, MD, PhD
Streszczenie
Wstęp. Żywice modelujące są często stosowane w celu zapobiegania przywieraniu kompozytów stomatologicznych do narzędzi i umożliwienia łatwiejszego kształtowania wypełnień. Istnieją różne metody nakładania żywicy modelującej na narzędzia, a ilość żywicy przeniesionej na kompozyt może się różnić w zależności od wybranej metody.
Cel pracy. Porównanie ilości i struktury żywicy do modelowania pozostającej między warstwami kompozytu, w zależności od procedury aplikacji.
Materiał i metody. Próbki kompozytowe modelowano pędzelkiem zanurzonym w żywicy modelującej zabarwionej rodaminą B. W grupie 1 próbki kompozytu modelowano bezpośrednio po zwilżeniu pędzelka żywicą, w grupie 2 pędzelek najpierw wycierano gazą w celu usunięcia nadmiaru żywicy, a następnie modelowano próbki kompozytu. Przekroje próbek analizowano za pomocą mikroskopu konfokalnego w celu pomiaru grubości i oceny morfologii warstwy żywicy modelującej.
Wyniki. Test t-Studenta wykazał statystycznie istotną różnicę między grupami (P < 0,00001). Warstwa była grubsza w grupie 1 o średniej grubości 26,44 ± 4,83 μm, w porównaniu z 15,65 ± 2,81 μm w grupie 2. Obraz mikroskopowy pokazuje, że żywica tworzy dość regularną warstwę na powierzchni modelowanego kompozytu.
Wnioski. Sposób nakładania żywicy na modelowany kompozyt wpływa na ilość żywicy wprowadzanej do wypełnienia. Wytarty pędzelek przenosi mniej żywicy do wypełnienia niż niewytarty. Parametr metody aplikacji powinien być brany pod uwagę w dalszych badaniach dotyczących żywic modelujących.
Summary
Introduction. Modeling resins are commonly used to prevent dental composites from sticking to instruments and allow easier sculpting of the restorations. There are various methods for applying modeling resin to tools, and the amount of resin transferred to the composite can vary depending on the chosen method.
Aim. To compare the amounts and structure of modelling liquid left between the composite layers, depending on the application procedure.
Material and methods. Composite samples were modelled using brush dipped into modelling resin dyed with rhodamine B. In the group 1 composite samples were modelled directly after wetting the brush in the resin, in the group 2 the brush was firstly wiped into dry gauze to remove resin excess and then composite samples were modelled. Crosscuts of the samples were analysed using confocal microscope to measure the thickness and assess the morphology of the modelling resin layer.
Results. Student’s t-test revealed statistically significant difference between the groups (P < 0.00001). Observed layer was thicker in the group 1 with mean thickness of 26.44 ± 4.83 μm, compared to 15.65 ± 2.81 μm in group 2. Microscope image shows that resin forms fairly regular layer on composite increment surface.
Conclusions. The method of applying the resin to the modelled composite results in differences in the amount of resin getting into the restoration. A wiped brush transfers less resin to the restoration than a not wiped one. Application method parameter should be taken into consideration during future studies regarding the topic of modelling resins.
Introduction
Direct composite restorations remain one of the most common and fundamental procedures performed in the dental office (1). Technical aspects of placing composite restoration involve its condensation into the prepared cavity and modelling of proper tooth morphology (2). Dental restorative materials based on resins tend to stick to the metal instruments during the application which impedes material modelling and increases the risk of closing air bubbles in the restoration (3, 4). One of the ways to prevent this problem is to cover application instrument with unfilled, modelling resin which composition is similar to organic matrix of composite materials (5). Possible introduction of the modelling resin into the restoration raises concern about consequent change in its properties (6, 7). This common clinical practice varies across different practitioners in terms of materials and tools used, as it is not officially recommended in the literature (8, 9).
There are many studies regarding the topic of instrument lubrication with unfilled resins, adhesive systems or even ethyl alcohol and influence of those substances on properties of the composites (8). Methodological differences among researchers make the results hard to compare. There is a need to evaluate the amount of lubricant permanently incorporated into the composite structure, depending on the application technique, with respect to accurate reproduction of clinical conditions.
Aim
The aim of the study was to evaluate the amount and structure of the modeling resin layer remaining on the modeled composite portion after modeling with a resin-wetted brush. Additionally, the amount of remaining resin was compared depending on the application technique.
Material and methods
Study design
The study included 2 test groups:
? group 1 – composite modelled with instrument dipped in unfilled resin without removing its excess,
? group 2 – composite modelled with brush dipped in unfilled resin with the excess wiped out with dry gauze until no visible traces were detected.
Samples preparation
Ten Enamel HRi UE2 (Micerium, Italy) composite samples were placed in round silicon moulds, 4 mm tall with a diameter of 10 mm, up to around half of the total height. The bottom of the mould was made of a glass plate. Five prepared samples were assigned to group 1, the remaining 5 to group 2. Free composite surface was then modelled with a disposable bonding brush (Pol-Intech, Poland) moistured with unfilled resin Enaseal (Micerium, Italy). Modelling consisted of 10 movements across the sample surface. New brush was used for every resin sample. The resin was labelled with fluorescent dye Rhodamine B (RB) (Warchem, Poland) according to the method described by Bim et al. (10) to obtain 0.1 mg/ml RB concentration. In the first group brush was dipped into a drop of resin and directly afterwards used for modelling of the composite. In the second group, before modelling, brush was additionally wiped with dry gauze until no marks of resin were visible on the gauze. Samples were then polymerized with Woodpecker iLED light-curing lamp (Woodpecker, China) for 20 seconds from both sides. The modelled surface was covered with flowable composite Filtek Ultimate Flowable (3M ESPE, USA) and light-cured to secure the labelled layer between composite increments. After removal from the moulds, samples were cut in half along the long axis of the sample using diamond cutting disc. Cut surfaces were then polished using sandpapers with the increasing grit up to 800.
Confocal imaging
Samples were observed using Nikon A1R MP multiphoton confocal microscope with Plan Apo VC 60x Oil DIC N2 lens (Nikon Europe B.V., Holandia) using 404 and 561 nm wavelength lasers for blue and red channels respectively. One image was acquired from the central area of each sample, giving 5 images for each group.
Using NIS-Elements software (Nikon Europe B.V., Holandia) the width of dyed resin was measured by one operator in 5 places of every sample image, resulting in 25 measurements for each study group.
Statistical analysis
Powyżej zamieściliśmy fragment artykułu, do którego możesz uzyskać pełny dostęp.
Mam kod dostępu
- Aby uzyskać płatny dostęp do pełnej treści powyższego artykułu albo wszystkich artykułów (w zależności od wybranej opcji), należy wprowadzić kod.
- Wprowadzając kod, akceptują Państwo treść Regulaminu oraz potwierdzają zapoznanie się z nim.
- Aby kupić kod proszę skorzystać z jednej z poniższych opcji.
Opcja #1
29 zł
Wybieram
- dostęp do tego artykułu
- dostęp na 7 dni
uzyskany kod musi być wprowadzony na stronie artykułu, do którego został wykupiony
Opcja #2
69 zł
Wybieram
- dostęp do tego i pozostałych ponad 7000 artykułów
- dostęp na 30 dni
- najpopularniejsza opcja
Opcja #3
129 zł
Wybieram
- dostęp do tego i pozostałych ponad 7000 artykułów
- dostęp na 90 dni
- oszczędzasz 78 zł
Piśmiennictwo
1. Cheng L, Zhang L, Yue L et al.: Expert consensus on dental caries management. Int J Oral Sci 2022; 14(1): 17.
2. Chandrasekhar V, Rudrapati L, Badami V, Tummala M: Incremental techniques in direct composite restoration. J Conserv Dent 2017; 20(6): 386-391.
3. Al-Sharaa KA, Watts DC: Stickiness prior to setting of some light cured resin-composites. Dent Mater 2003; 19(3): 182-187.
4. Ertl K, Graf A, Watts D, Schedle A: Stickiness of dental resin composite materials to steel, dentin and bonded dentin. Dent Mater 2010; 26(1): 59-66.
5. Kutuk ZB, Erden E, Aksahin DL et al.: Influence of modeling agents on the surface properties of an esthetic nano-hybrid composite. Restor Dent Endod 2020; 45(2): e13.
6. Barcellos DC, Pucci CR, Torres CR et al.: Effects of resinous monomers used in restorative dental modeling on the cohesive strength of composite resin. J Adhes Dent 2008; 10(5): 351-354.
7. Lee JH, Um CM, Lee IB: Rheological properties of resin composites according to variations in monomer and filler composition. Dent Mater 2006; 22(6): 515-526.
8. Kosewski J, Kosewski P, Mielczarek A: Influence of instrument lubrication on properties of dental composites. Eur J Dent 2022; 16(4): 719-728.
9. Ritter AV, Walter R, Boushell LW, Ahmed SN: Clinical technique for direct composite resin and glass ionomer restorations. [In] Ritter AV, Boushell LW, Walter R (eds.): Sturdevant’s art and science of operative dentistry. Elsevier, St. Louis 2019: 219-263.
10. Bim Junior O, Cebim MA, Atta MT et al.: Determining optimal fluorescent agent concentrations in dental adhesive resins for imaging the tooth/restoration interface. Microsc Microanal 2017; 23(1): 122-130.
11. Rastelli AN, Jacomassi DP, Faloni AP et al.: The filler content of the dental composite resins and their influence on different properties. Microsc Res Tech 2012; 75(6): 758-765.
12. Htang A, Ohsawa M, Matsumoto H: Fatigue resistance of composite restorations: Effect of filler content. Dent Mater 1995; 11(1): 7-13.
13. Tuncer S, Demirci M, Tiryaki M et al.: The effect of a modeling resin and thermocycling on the surface hardness, roughness, and color of different resin composites. J Esthet Restor Dent 2013; 25(6): 404-419.
14. Turssi CP, Ferracane JL, Serra MC: Abrasive wear of resin composites as related to finishing and polishing procedures. Dent Mater 2005; 21(7): 641-648.
15. Bayraktar ET, Atali PY, Korkut B et al.: Effect of modeling resins on microhardness of resin composites. Eur J Dent 2021; 15(3): 481-487.
16. Patel J, Granger C, Parker S, Patel M. The effect of instrument lubricant on the diametral tensile strength and water uptake of posterior composite restorative material. J Dent 2017; 56: 33-8.
17. Barcellos DC, Palazon M, Pucci CR et al.: Effects of self-etching adhesive systems used in the dental modelling technique on the cohesive strength of composite resin. The Journal of Adhesion 2011; 87(2): 154-161.
18. Munchow EA, Sedrez-Porto JA, Piva E et al.: Use of dental adhesives as modeler liquid of resin composites. Dent Mater 2016; 32(4): 570-577.
