The journal and publisher would like to inform the readers that this paper has been retracted. The journal had been informed by one of the co-authors, Jack van Loon, that he had noticed after publication that Fig. 1 of the article had been taken from the internet and masked, giving the wrong impression that it is showing the setup used in the studies discussed in the paper. Further investigations by the publisher revealed a significant textual overlap with the paper “Srisurang et al., Journal of Investigative and Clinical Dentistry (2011), 2, 23–28”.

While never admitting plagiarism the first author communicated to the journal the following retraction note:

“We are withdrawing this manuscript because of improper citation of references, caption errors as well as need to obtain stronger evidences and methods to establish our claim. We are extremely sorry for inconvenience to journal.”

The co-author, Jack van Loon, strongly dissociates himself from that note adding the remark that, “unfortunately and in my view, this publication had to be withdrawn because of plagiarism and false information within the paper without me knowing.”