Ash-Shaykh Abdul Muhsin Al-Abaad was asked the following question
Does the toothbrush take the place of the siwaak specifically in the lands which there is no siwaak except a little, like in Europe?
Yes, this is possible. It takes its place because the intent is to clean and purification. However, a person using a miswak and being concerned to use it, even though it may not be found in his land, no doubt it is more deserving. However, no doubt [the tooth brush] takes its place because the intent is cleanliness. Yes”
[Sharh Ibn Majah no. 33]
Faisal Ibn Abdul Qaadir Ibn Hassan