Development of swelling following orthognathic surgery at various cooling temperatures by means of hilotherapy-a clinical, prospective, monocentric, single-blinded, randomised study.

[PURPOSE] An alternative cooling method in oral and maxillofacial surgery is post-operative cooling with hilotherapy. It has not yet been clarified how the development of pain and swelling progresses post-operatively at different cooling temperatures. The aim of this study was the post-operative comparison of cooling temperatures of 18 °C and 22 °C. The parameters of this trial were swelling and the post-operative development of pain levels. In addition, the need for analgesics and patient satisfaction were documented.

[MATERIALS AND METHODS] This study included 36 patients, divided into two groups among whom a mono-one or bignathic osteotomy or genioplasty in orthognathic surgery was indicated. After the intervention, hilotherapy was employed directly instead of the conventional cooling method with moist compresses. The post-operative check of swelling during and after hilotherapy was performed using a 3D optical scanner (FaceSCAN3D). This examination was repeated on post-operative days 1, 2, 3, 7, 14, 30 and 90. In this process, the final examination on day 90 served as a reference value in respect of swelling and pain.

[RESULTS] Group 1 (18 °C, 18 patients) showed an increase in post-operative swelling on the 1 post-operative day of 62.22 ± 36.29 ml. The maximum was reached on the 3 post-operative day with 81.85 ± 40.23 ml. On the 30 post-operative day, residual swelling measured 7.39 ± 15.77 ml (p = 0.016). Group 2 (22 °C, 18 patients) showed an increase in postoperative swelling on the 1 post-operative day of 61.69 ± 34.7 ml. The maximum was reached on the 2 post-operative day with 92.83 ± 48.03 ml. On the 30 post-operative day, residual swelling measured 28.09 ± 19.04 ml (p = 0.016).

[DISCUSSION] The study results indicate slightly less residual swelling in group 1 (18 °C) on the 30 post-operative day. One possible reason for this, based on the design of the study, could be the lower cooling temperature. The post-operative pain development exhibits a comparable level of pain intensity between the two groups. In overall terms, a subjectively more agreeable treatment was observed in group 1 (18 °C).