By: Lee Ann Brady, DMD
This topic originally appeared on PankeyGram.org. Dr. Brady granted permission for igniteDDS to share with our readers.
Patients produce the S sound by creating a small airspace between their upper and lower incisors, and there are three common ways this happens:
- The lower incisors are just lingual to the upper incisal edges.
- The lower incisors are edge-to-edge with the uppers.
- The lower incisors are just labial to the upper incisors.
In each case, the ideal space for producing the S sound is approximately 100 microns.
How Restorative Dental Treatment Can Impact The S Sound
If the space is too small between the upper and lower incisal edges, the patient might develop a lisp or experience a clicking sensation as their teeth bump into each other. Conversely, if the space is too large, they may feel like they’re spitting or notice saliva escaping through the gap when they say S.
The time to observe this problem is when the patient is in provisionals—hopefully not when the patient is in final ceramics.
Correcting The Incisal Edge Gap
Patients won’t naturally adapt to S sound issues. If they have a lisp, we must adjust the space to eliminate it. On the other hand, if they feel like saliva is escaping during the S sound, the space is too large, and we’ll need to reshape the provisionals to reduce it slightly.
I use Madam Butterfly silk, a ribbon with red ink that’s about 96 microns thick, nearly the perfect spacing for the S sound. I place the ribbon on Miller forceps and position it between the incisal edges of the teeth. Then, I sit the patient upright and ask them to count from 60 to 70, incorporating plenty of S sounds.
As they count, I observe where the ribbon leaves red marks on their incisal edges. These marks indicate where the teeth are coming too close together. To correct this, I adjust the teeth until the patient can count from 60 to 70 without the ribbon leaving red marks on the upper or lower incisors.
Where to adjust depends on the patient’s S sound position:
If the marks are on the incisal edges of the maxillary incisors, I make adjustments on the lower teeth.
For edge-to-edge S sound speakers, all adjustments are made on the lower teeth.
If the marks are on the lingual side of the upper anteriors or the labial side of the lower anteriors, I may adjust either area.
For patients who say S with their lower incisors labial to the uppers, I adjust the lingual surfaces of the lowers, avoiding the labial of the uppers unless they appear bulky or thick. In such cases, I might adjust the uppers to improve both aesthetics and phonetics.
In Conclusion
By carefully fine-tuning these adjustments, we can not only restore proper phonetics but also enhance the overall patient experience, ensuring that their smile is as functional as it is beautiful.
Learn more about this topic by watching my video on Restorative Nation clinical collection, or join Essentials 3, a series of hands-on courses aiming to help dentists achieve an ideal balance of form and function in complex restorative cases. Reserve your place for Essentials while you still can – limited spots left even for 2026 dates!
