Original sentence: It is possible to split some kinds of dental floss lengthwise turning generating a pair of thinner pieces that are also weaker but sometimes useable.This can be useful if the dental floss you have is too thick, and you do not have access to any other, for example when travelling in a foreign country
Edited sentence: It is possible to split some kinds of dental floss lengthwise  generating a pair of thinner pieces that are much weaker but sometimes useable.This can also be useful if the dental floss you have is too thick for you, for any other reason, and you do not have access to any other, for example when travelling in a foreign country