Apex domains cannot have CNAME records.
Question and response
Question
dig dentsplycaulk.com. NS
Answer
dentsplycaulk.com. 5 NS ns-416.awsdns-52.com.
dentsplycaulk.com. 5 NS ns-366.awsdns-45.com.
dentsplycaulk.com. 5 NS ns-978.awsdns-58.net.
dentsplycaulk.com. 5 NS ns-952.awsdns-55.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0