Since 4.3 it is possible to have UTF-8 characters in the names of the nodes. However some of such characters do not pass security checks and once inserted will result in access to the node/page being denied to a user. Example is small latin th character with strikethrough (U-1D7A).
To reproduce:

• log in as superuser and create page in AdminCentral
• enter the character in the name of the page
  The error message saying user doesn't have access to the node will appear as a result. Making dump of the nodes in Tools/JCR queries will show the page with the utf character in the name properly, however the page is no longer visible in the website view in AdminCentral.