Effects of toothbrushing on surface characteristics of microhybrid and nanofilled resin composites following different finishing and polishing procedures

Alaa Daud; Alexander J Adams; Athra Shawkat; Gordon Gray; Nairn H F Wilson; Christopher D Lynch; Igor R Blum

doi:10.1016/j.jdent.2020.103376

Effects of toothbrushing on surface characteristics of microhybrid and nanofilled resin composites following different finishing and polishing procedures

J Dent. 2020 Aug:99:103376. doi: 10.1016/j.jdent.2020.103376. Epub 2020 May 26.

Authors

Alaa Daud¹, Alexander J Adams², Athra Shawkat³, Gordon Gray⁴, Nairn H F Wilson⁵, Christopher D Lynch⁶, Igor R Blum⁷

Affiliations

¹ College of Dental Medicine, Qatar University, Doha, Qatar.
² Royal Devon and Exeter Hospital, UK.
³ Dental practice, UK.
⁴ School of Oral & Dental Sciences, University of Bristol Dental School, UK.
⁵ King's College London, UK.
⁶ University Dental School & Hospital, University College Cork, Wilton, Cork, Ireland.
⁷ Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, UK; Maurice Wohl Dental Outreach Centre, West Norwood Health & Leisure Centre, 25 Devane Way, London SE27 0DF, UK. Electronic address: igor.blum@kcl.ac.uk.

PMID: 32470566
DOI: 10.1016/j.jdent.2020.103376

Abstract

Objectives: To evaluate the effects of simulated tooth brushing (STB) on the surface roughness of microhybrid and nanofilled resin composites following different finishing and polishing procedures.

Materials and methods: Ninety cylindrical-shaped specimens of Filtek Supreme XT (a universal nano resin composite) and Filtek Z250 (a universal microhybrid resin composite) were prepared. The specimens were allocated at random into 9 paired groups each of 10 specimens. The finishing and polishing systems included were Tungsten Carbide bur (TC); Diamond bur (Db); Sof-Lex discs (S); PoGo discs (PG); TC + S; Db + S; TC + PG; Db + PG. Polymerisation against a Mylar strip without finishing and polishing acted as the control. Surface roughness was measured using a 3D non-contact optical profilometer and surface morphology was examined by scanning electron microscopy. Specimens were subjected to the equivalent of four years STB and surface roughness was measured again.

Results: Mylar formed surfaces were the smoothest for both composites before and after STB. Finishing with the diamond finishing bur caused significantly greater surface irregularity (p < 0.0001) before and after STB compared to the tungsten carbide bur. The surface treatment with Db + PG resulted in significantly greater surface roughness following STB than all other regimes of finishing and polishing (p < 0.01).

Conclusion: Where indicated clinically, ﬁnishing is better conducted using a tungsten carbide bur rather than a diamond ﬁnishing bur. The combination of tungsten carbide bur/Enhance PoGo and tungsten carbide bur/Sof-Lex surface protocols produced a similarly smooth finish for both composites. The composite surfaces in all groups increased in surface irregularity following STB. CLINICAL SIGNIﬁCANCE: Whilst ﬁnishing using a tungsten carbide ﬁnishing bur followed by either the Sof-Lex or PoGo polishing system may be found to result in a smooth surface ﬁnish, all the surfaces investigated increased in surface roughness following toothbrushing.

Keywords: Finishing procedures; Resin composites; Surface roughness; Toothbrushing.

MeSH terms

Composite Resins
Dental Polishing*
Materials Testing
Microscopy, Electron, Scanning
Surface Properties
Toothbrushing*

Substances

Composite Resins