Research index·Journal articlePeter Douglas BirdDavyBDJ·27 Apr 2012·Open accessDOI10.1038/sj.bdj.2012.362Journal articleOpen accessPeter Douglas BirdDavy · BDJ · 2012DOI10.1038/sj.bdj.2012.362ReadRead PDFSaveCiteAdd to literature reviewDiscussionAdd to the discussionTopicsHistoryRelated papersMoreDetailsPublished, publisher, issueSuggest a correction or report