Evaluation of microleakage in class-II bulk-fill composite restorations

Alaa Turkistani; Adnan Nasir; Yasser Merdad; Ahmed Jamleh; Ehab Alshouibi; Alireza Sadr; Junji Tagami; Turki A Bakhsh

doi:10.1016/j.jds.2020.04.007

Evaluation of microleakage in class-II bulk-fill composite restorations

J Dent Sci. 2020 Dec;15(4):486-492. doi: 10.1016/j.jds.2020.04.007. Epub 2020 May 11.

Authors

Alaa Turkistani¹, Adnan Nasir², Yasser Merdad¹, Ahmed Jamleh³, Ehab Alshouibi⁴, Alireza Sadr⁵, Junji Tagami⁶, Turki A Bakhsh¹

Affiliations

¹ Restorative Dentistry Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
² Department of Diagnostic Sciences, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
³ King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
⁴ Department of Dental Public Health, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
⁵ Department of Restorative Dentistry, University of Washington, Seattle, WA, USA.
⁶ Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.

Abstract

Background/purpose: Despite the clinical appeal of restoring deep class II cavities in single increment using bulk-fill resin composite, sealing of bulk-filled composite restorations is a concern. This study evaluated interfacial adaptation of bulk-fill composite restoration to axial wall and gingival floor of class II cavities using cross-polarization optical coherence tomography (CP-OCT).

Materials and methods: Box-shaped class II cavities were prepared in extracted molars and divided into three groups (n = 7) according to adhesive used; Clearfil SE Bond 2 (SE2), Tetric-N Bond Self-Etch (TSE) or Tetric-N Bond Universal (TNU). All adhesives were applied in self-etch mode and according to manufacturers' recommendation. Then, preparations were bulk-filled with Filtek Bulk Fill Posterior Restorative resin composite and immersed in a contrast agent. Tomographic images of axial wall and gingival floor of each restoration were obtained by CP-OCT (IVS-300, Santec) with a central wavelength of 1330 nm and were imported to an image analysis software to quantify microleakage.

Results: Mann-Whitney U test showed statistically significant difference in microleakage percentage between the groups at both axial wall and gingival floor (p < 0.05). SE2 group had the lowest percentage of microleakage (p < 0.05), as only few cross-sections showed areas of reflections from contrast agent penetrating into axial wall (8.23 ± 6.8) and gingival floor (7.07 ± 4.1), followed by TNU group (18.13 ± 12.9 axially and 30.61 ± 11.9 gingivally). Microleakage was frequently observed at the axial wall and gingival floor of TSE group, showing the highest percentages of 25.50 ± 12.5 and 36.97 ± 10.2, respectively (p < 0.05).

Conclusion: All tested groups exhibited different extent of interfacial microleakage, however, two-step self-etch adhesive yielded superior adaptation in comparison to one-step self-etch adhesive and universal adhesive.

Keywords: Adhesive; Bulk-filled; Composite-resins; Microleakage; Optical coherence tomography.