*739Plaintiffs sought relief from Special Term from an unconditional order of preclusion granted on default, based upon their failure to respond to defendants’ demands for bills of particulars. Special Term properly denied the motion to vacate for lack of an affidavit of merit from an expert competent to testify to evidentiary facts which would support plaintiffs’ claim of professional malpractice (Horvath v Bayonne Hosp., 99 AD2d 824; Nelson v Eastman Dental Center, 85 AD2d 887). Furthermore, plaintiffs’ attorney did not set forth any reasonable excuse for the failure to comply with defendants’ demands in a timely fashion, although plaintiffs were able to comply when faced with a motion and cross motion for summary judgment (Horvath v Bayonne Hosp., supra; De Vito v Marine Midland Bank, 100 AD2d 530).

Since Special Term did not abuse its discretion in denying the cross motion to vacate, the judgment is affirmed (Fidelity & Deposit Co. v Andersen & Co., 60 NY2d 693). Mangano, J. P., Brown, Niehoff and Lawrence, JJ., concur.