The term 'spaces between teeth' is often used to refer to the GAPS that can form between teeth due to missing teeth, misalignment, or other dental issues. The crossword solution for this term is 'GAPS, ' which is a four-letter word. GAPS between teeth can be caused by a variety of factors, including genetics, poor oral hygiene, and certain medical conditions. Treatment options for GAPS between teeth include braces, veneers, and dental implants.