Have you ever been at a meeting that you did not know everyone there. I would guess that the meeting took a long time to get started or never really ever got off the ground. If the people at the meeting do not know each other, the meeting will move much more quickly if you take a little time to include everyone. I mean to do just a little more than having everybody say who they are. The best way is to have people say something that is not controversial but relevant to the subject of the meeting.
For example how long have they been aware of the issue or what is there role related to the subject. Another a little more risky is why they think they are at the meeting. The inclusion exercise is best used following to chair reviews the agenda. Another very open question for people who all know each other is "What’s new?" I think every meeting to be effective and efficient should start with an inclusion exercise.
You will be amazed how much more quickly the meeting goes and how quickly things get decided when people feel included. People want to feel a part of things so include them.