Abu Hurayrah (may Allah be pleased with him) reported that the Messenger of Allah (may Allah’s peace and blessings be upon him) said: “Were it not that I would cause difficulty for my followers, I would command them to use the tooth-stick with every prayer.”
In this Hadīth, the Prophet (may Allah's peace and blessings be upon him) makes clear that were it not for his fear to cause difficulty and hardship for his followers, he would command and obligate them to use the tooth-stick with every ablution. But, out of his mercy and compassion towards them, he did not do that. Instead of prescribing it as an obligation, he made it a recommended act of Sunnah, whose performance brings reward, yet there is no punishment for failure to do it.