Successfully producing speech sounds involves an intricate coordination between a person’s oral structures and muscles. The oral structures that are involved in speech production are the lips, teeth, tongue, cheeks and vocal tract. Although some structures have a more direct role than others, all play a role in producing intelligible speech. When one structure is taken out of the equation, the ultimate product – speech – may be affected. During the current blog we are going to discuss how a child’s dentition will affect a person’s speech.
How Does Dentition Affect Speech?
Dentition plays an interesting role in a child’s speech as his or her teeth are still developing. Teeth will come and go as baby teeth are lost and permanent adult teeth grow in and incorrect bites are corrected with braces. Throughout these changes, a child’s articulation may or may not be affected. There are certain sounds that depend on teeth for correct articulation. For example, when producing the sound “f”, you need your teeth to bite down on your lip in order to cause the friction with your air source to make the sound. If your front teeth are missing that sound will be distorted.
There are a group of sounds that are classified as “strident” sounds. Strident sounds are produced by the friction of a fast airflow being pressed against a speaker’s teeth. Strident sounds include: /f/ (“fish”), /v/ (“vet”), /s/ (“sew”), /z/ (“zoo”), /tʃ/ (“chin”), /dʒ/ (“gym”), /ʃ/ (“shoe”), /ʒ/ (e.g., medial sound in “treasure”). Other sounds that are articulated in the front of a speaker’s mouth (i.e., in between your upper teeth and lower lip”) that could be affected by dentition are voiced and voiceless “th” (e.g., “the” and “thirst”).
Typically if a child can articulate the sound correctly before the loss of a tooth, then the child will maintain that skill while the adult tooth comes in. However, it is important to be aware that the sound may be distorted or sound funny while that tooth is missing, although it will only be temporary. The strident sounds may sound distorted due to the fact that there is nothing in the child’s mouth to cause the additional friction that that sound relies on, resulting in an “airier” sound.
The effect of dentition on speech becomes more complicated when a child has both an articulation disorder, as well as an incorrect bite (e.g., “open bite”). For example, if a child is working on correctly producing the sound /s/, but also has an open bite, it will be difficult for them to reach that speech goal due to the fact that structurally, their teeth are not in the ideal position for that sound. This is a great opportunity for that child’s speech-language pathologist and orthodontist to collaborate together on a therapy plan or timeline. Ultimately, having a correct bite or dentition will have a positive impact on a child’s ability to produce intelligible speech.