Text and Data Mining valid from 2019-04-16
Received: 18 February 2019
Accepted: 8 April 2019
First Online: 16 April 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: The methods were carried out in accordance with the 1964 Declaration of Helsinki, and the cadavers were legally donated for the research by the Nippon Dental University of Life Dentistry at Niigata in Japan.
: Informed consent was obtained from the families of all subjects.
: The data sets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.