These sounds are formed with the tongue tip behind the upper front teeth. The initial sound of thin and the final sound of bath are both voiceless dentals. The symbol used for this sound is [θ], usually referred to as “theta.” It is the symbol you would use for the first and last sounds in the phrase three teeth.

 The voiced dental is represented by the symbol [ð], usually called “eth.” This sound is found in the pronunciation of the initial sound of common words like the, there, then and thus. It is also the middle consonant sound in feather and the final sound of bathe. The term “interdentals” is sometimes used for these consonants when they are pronounced with the tongue tip between (= inter) the upper and lower teeth.