Thank you for your question. Both interproximal reduction (IPR) or teeth extraction are methods to create space to achieve either 1) improvement in teeth alignment or 2) improvement in the teeth inclination. Interproximal reduction yields only modest amount of space as there is a limit to how much tooth enamel can be reduced, a safe amount of tooth reduction is less than 0.5mm per surface. Tooth extraction will give your dentist about 7-8mm of space from the removal of usually a premolar tooth. (There are instances where other teeth can be extracted and this is very case dependent) Hence, tooth extraction yields more space and can therefore correct tooth inclination to a greater degree and this may also help with the lip profile in some cases.
Everyone has different expectations on what "best" results mean to them, if one prioritises retaining all their teeth and prefers absolutely no extraction then that should be communicated to your dentist. However if your preference is to have straighter teeth with a more ideal inclination (i.e more upright) then extractions may be warranted.
Communicating to your dentist what are the key areas you would like to correct will be paramount and would also greatly help your dentist especially if your case is borderline, meaning you could manage it either with IPR or with extractions.
Hope this helps and all the very best,
Dr Priscilla Lu
Orthodontist
