The DHC-8-400 has been dogged by tech problems since launch, many of which have been swept under the carpet, many operators have had to work with Bombardier to troubleshoot issues.
There IS a blatant problem with the Q400 landing gear, that's not to say the aircraft is inherently dangerous but should be grounded and/or under a close inspection schedule until a proper explanation can be found. Whether its being caused by an SAS maintenance issue, an operational factor or a design flaw we will have to wait and see.
With a fleet of 27 aircraft available for scrutiny and EASA, national aviation authorities and Bombardier engineers all wanting to find the causes, I'm sure it wont be long until some answers are published.