How well are you viewed by your management normally? Any problems or negative relationships? I ask because I note that you have only 9 months service, and as you may well be aware you have considerably less protection than if you had completed a year.
That said, the suspension itself is a reasonable act, and would be normal procedure for an allegation of this nature. Understandably as you are innocent, you wish to be found as such and allowed to continue your employment. Do you have a Union? You will be entitled to have either a colleague or Union rep present at any disciplinary hearing, so I suggest that you exercise this right. If the meeting next week is only a preliminary investigatory hearing then you do not have the right to be accompanied, but you should still make copious notes and use every opportunity to defend your position. You should strenuously deny the allegation, offer to provide witnesses either of the incident with the first aid box, or to your character in general at the earliest opportunity.
Beyond a robust denial and expression of utter bewilderment at the allegations, there is little that you can do, and I sincerely hope that the employer is sensible enough to listen and act with common sense, as I fear that without the requisite length of service (and the right to take action for unfair dismissal that goes with it), they may err on the side of caution and decide to give in to pressure from the apprentice and his father!