Hyperbaric Oxygen Therapy (HBOT) is a stress-free, relatively safe method supporting the treatment of many different diseases. Although it is widely used in human medicine (including dentistry), in veterinary medicine, especially in the treatment of horses, there are not many scientifically described and documented cases of its use. Equine Odontoclastic Tooth Resorption and Hypercementosis syndrome is a disease that affects older horses and significantly reduces their quality of life. The only effective treatment for this condition is extraction of the incisors. The described case compares the recovery process of the alveolar area after extraction of incisors during the course of EOTRH syndrome without and with the use of a chamber, in horses with the same clinical picture of the disease, of the same age, and living in the same conditions. According to the authors’ knowledge, the presented case describes the use of a chamber in equine dentistry for the first time.