Difference Between Tooth and Teeth
The tooth and the teeth are two words that are often used as interchangeable words although it is incorrect to do. There is indeed a difference between them when it comes to their use.
‘Tooth’ is used in singular form, while ‘teeth’ is plural. The word ‘tooth’ is often used with ‘ache’ as in ‘toothache’. While it is grammatically correct to say ‘toothache’, but it is incorrect to say ‘teethache’. Similarly it is ‘the toothpick’ and not ‘teethpick’.
Similarly the word ‘teeth’ is used as a collective noun. For example, in the sentence ‘brushes the teeth properly’. In this sentence you can see that the word ‘teeth’ is used in the collective sense as the plural of the word ‘tooth’. The idea is that each tooth should be brushed properly is understood by the use of the sentence mentioned above.
Similarly in ‘tooth -whitening’, note that singular form is used in words with a hyphen. The phrase or the word ‘teeth whitening’ is incorrect. Hence, ‘teeth whitening is a cosmetic procedure’ is incorrect. It should be replaced with ‘tooth-whitening’.
Similarly, in sentences like ‘show your teeth’, ‘teeth’ is used again in the collective sense. It does not talk about each tooth individually. The dentist examines the patient’s teeth instead of a particular tooth to begin with. These are the differences between the two words ‘tooth’ and ‘teeth’.