This is the second action arising out of an incident at Humana dospital-Newnan in which Inez Hodo was injured. We conclude that ;he dismissal of Hodo’s first action for failure to file an affidavit pursuant to OCGA § 9-11-9.1 is res judicata here, and we affirm the trial :ourt’s grant of summary judgment on that basis.

During a physical therapy session conducted by Elijah Basa at he hospital, Hodo fell and was injured. She brought suit in Fulton bounty State Court against Humana Hospital-Newnan, alleging negligence on the part of the hospital in conducting the physical therapy, ^s the action progressed, it became apparent that Hodo was alleging negligence on the part of Elijah Basa and seeking to hold the hospital iable through the doctrine of respondeat superior. The hospital noved for summary judgment on three grounds: first, that Hodo ailed to comply with the affidavit requirement of OCGA § 9-11-9.1; iecond, that Hodo failed to show negligence on the part of the physi:al therapist; and third, that Hodo had failed to show causation.

The trial court granted the hospital’s motion in a brief order. On notion for reconsideration, the trial court clarified its original order, toting that Hodo’s claim was based on the alleged professional negli;ence of Basa and an affidavit therefore was required under OCGA ¡ 9-11-9.1. The court also noted there was undisputed testimony that Basa complied fully with the appropriate standard of care. Hodo ap-pealed to this court. In Hodo v. Gen. Hosps. of Humana, 211 Ga. App. 6 (438 SE2d 378) (1993), this court affirmed on the basis of iodo’s failure to comply with the affidavit requirement, treating the >rder as a dismissal for failure to state a claim under OCGA § 9-11-M. The opinion notes that the claim was based upon Basa’s exercise >f professional judgment. 211 Ga. App. at 8.

While the first action was on appeal, Hodo brought another ac-ión in the Superior Court of Floyd County, naming Basa as the sole lefendant and alleging negligence in providing physical therapy. Basa noved for summary judgment on the basis of res judicata and collateral estoppel, and the trial court granted his motion in a comprehenive and well-reasoned order. This appeal followed.

1. Hodo contends the trial court erred in granting summary judg-nent to Basa on the basis of res judicata. “[U]nder the doctrine of res udicata, a judgment on the merits in a prior suit bars a second suit nvolving the same parties or their privies based on the same cause of *896 action.” (Citations and punctuation omitted.) Sorrells Constr. Co. v. Chandler Armentrout &c., P. C., 214 Ga. App. 193 (447 SE2d 101) (1994). This doctrine will bar a second action “if the plaintiff has brought another action based on the same subject matter, the plaintiff had a full and fair opportunity to litigate the other action, the other action resulted in an adjudication on the merits, and the othei action was against the same defendant or its privy. [Cit.]” Id. at 194.

Hodo’s claims in both actions obviously involve the same subject matter and the same cause of action. She had a full and fair opportunity to litigate the controlling issues in the original action, botl before the trial court and this court. She argues, however, that the dismissal of her first action for failure to file an affidavit under OCGA § 9-11-9.1 was not an “adjudication on the merits” for purposes of res judicata. This contention was decided adversely to Hodo in her first appeal. See 211 Ga. App. at 8.

Contrary to Hodo’s contention, Lutz v. Foran, 262 Ga. 819, 824 (4) (427 SE2d 248) (1993), decided after Hodo filed her original com plaint, does not require a remand here. With respect to the issue o: whether a final adjudication on the merits had occurred, Lutz did no establish any new rule of law limited to prospective application. I merely restated existing principles. 1 The Code section itself clearb states that a dismissal under OCGA § 9-11-9.1 is a dismissal for fail ure to state a claim, and the complaint cannot be renewed o amended without a judicial determination that the affidavit was avail able but not filed due to mistake. See OCGA § 9-11-9.1 (e), (f). Th< Georgia Supreme Court noted as early as 1976 that “the sustaining o a motion to dismiss for failure to state a claim is res judicata on tb merits of the claim.” Dillingham v. Doctors Clinic, P. A., 236 Ga. 302 (223 SE2d 625) (1976). The dismissal of Hodo’s first action was a fina adjudication on the merits.

Hodo also contends that the first action was not res judicata be cause of an absence of privity between the hospital, the sole defend ant in the first action, and Basa, the sole defendant in the secon< action. Generally, a servant is not in privity with his master so as t be able to claim the benefit of an earlier adjudication in the master’ favor. Gilmer v. Porterfield, 233 Ga. 671, 674 (2) (212 SE2d 842 (1975). “However, in McNeal v. Paine, Webber, Jackson & Curtis Inc., 249 Ga. 662 (2) (293 SE2d 331) (1982), the Court held that thi rule applies only in cases, such as Gilmer, where there are defense which are available to the master but not available to the servanl Where the master is sued under the doctrine of respondeat superio *897 for actions of the servant within the scope of the servant’s authority, and there are no defenses available to the master which are not available to the servant, the action adjudicating the master’s liability is res judicata and bars a subsequent action against the servant.” Brinson v. First American Bank, 200 Ga. App. 552, 555-556 (4) (409 SE2d 50) (1991).

The first action was based on the alleged negligence of Basa in performing his duties as a physical therapist employed by the hospital. While the complaint did not explicitly allege the doctrine of re-spondeat superior, it asserted liability on the part of the hospital for Basa’s negligence. Moreover, Hodo has acknowledged in this action that the earlier action was brought under the theory of respondeat superior. In its answer, the hospital did not raise a defense of lack of authority or that Basa was acting outside the scope of his employment. It simply asserted that no agent, employee, or representative of the hospital caused any injury alleged by Hodo. Because the earlier action which resulted in judgment for the hospital was based on the alleged negligence of Basa, Hodo could not relitigate “this actually itigated and necessarily decided issue.” Sorrells, supra at 194. The trial court did not err in granting Basa’s motion for summary judgment on the basis of res judicata.

2. In view of the holding in Division 1, Hodo’s remaining enumerations of error are rendered moot.

Judgment affirmed.