This advice-column-style blog for SLPs was authored by Pam Marshalla from 2006 to 2015, the archives of which can be explored here. Use the extensive keywords list found in the right-hand column (on mobile: at the bottom of the page) to browse specific topics, or use the search feature to locate specific words or phrases throughout the entire blog.
Q: My client has an anterior open bite, a very strong thumbsucking habit, and a frontal lisp of S and Z. My first impression is to wait to work on speech until after the teeth are firmly in place and the sucking habit is eliminated. Do you agree with this?
Yes. In regard to the teeth, it is my opinion that it does no good to work on the sibilants until the “anterior dental barrier” (consisting of the front teeth) is in place for production of frication through the tongue’s central groove.
The oral habit may be interfering with the development of oral structure and function depending upon frequency (how often the client does it), duration (how long he sucks each time he does), and intensity (how much pressure he exerts upon his tongue and teeth when he sucks). In the best of circumstances, the oral habit is eliminated either before or during therapy to afford the best possible oral structure and function for production of the sibilants.
Charles Van Riper taught that we should teach the client compensatory movements and positions If the client will not receive permanent front teeth, fo whatever reason. This means that we are to teach the client to produce the best S and Z he can, given his structural differences.