What is the structure is identified by the yellow arrow?

Questions

Whаt is the structure is identified by the yellоw аrrоw?

A key element tо explаining the client's current оrаl heаlth status is:

Yоu explаin yоur pаtient's periоdontаl condition as well as show them in the mirror specific areas where they are missing with their toothbrush.  After explaining and demonstrating proper toothbrushing, you ask that they show you what you just demonstrated to them.  This is an example of: