Answered by Mufti Mohammed Tosir Miah
Swallowing food stuck between the teeth in Salah
The ruling is similar to a person fasting.
If a person swallows the traces of food that remains in between his teeth it does not break the Salah provided it is less than the size of a chickpea. The reason the Salah will not be nullified, if the food is less than a chickpea is that it is considered part of the saliva. If it is bigger than a chickpea, ones Salah will break. (Maraqi Falah p.123)
Only Allah Knows Best
Mohammed Tosir Miah
Darul Ifta Birmingham.