Muscles of submandibular region

• First muscular plane


  Digastric and stylohyoid
• Second muscular plane 


  Mylohyoid
• Third muscular plane


  geniohyoid, hypoglossus, styloglossus
• Fourth muscular plane 


  Genioglossus and part of superior constrictor
• Hyoglossus is the key muscle of submandibular region