for ur kind concern ..mark it ...once tooth structure is been decayed means a calcified hard structure is been decalcified and we dentist can not calcify those structure except in some very initial case we just seal it with sealant so decalcified stucture is been excavated and filled with hard structure and as advancing technology we hv some gels that avoids as drilling , have lasers for excavation but becomes expensive side

A small cavity if is a pit and fissure cavity- can be cured by applying sealants. However if the cavity is having a catch and is a proper cavity- a filling after minimal drilling is mandatory failing of which will cause the cavity to deepen. Without drilling- laser is an option - but it's expensive and there is not much need of it. Always better to drill n fill. The other teeth if there is pain or the cavity is approaching the pulp a root canal might be needed lest a filling will solve the problem

Hi Small pit and fissured cavity can be cured by application of sealants .Larger cavity should go for xray for depth of the cavity and then sealed with filling or root canal therapy if required.

If there is a cavity in the tooth than it cannot be cured by itself. It can be removed without drill sometimes if it’s very superficial. The other tooth required removal of the decay and filling with tooth coloured cement.