Background/Aim. Mandibular prognathism as one of the more severe forms of dentofacial deformities impairs the oral functions and appearance of the patient's face and represents a psychosocial handicap with a negative impact on their quality of life. This study aims was to assess the impact of orthodontic-surgical treatment on the quality of life of patients with mandibular prognathism. Methods. The study involved 40 patients (19 men and 21 women, mean age 24.1 ± 4.10) who underwent orthodontic-surgical treatment of mandibular prognathism. All patients completed two questionnaires, the Oral Health Impact Profile (OHIP-14) and the Orthognathic Quality of Life Questionnaire (OQLQ), before the start of treatment and 12 months after the completion of treatment. Results. Both questionnaires showed an improvement in the quality of life compared to the condition before the start of treatment. According to the OQLQ questionnaire, there was a postoperative improvement in quality of life (M = 24.83 ± 12.99) compared to the preoperative period (M = 51.28 ± 15.2). According to the OHIP questionnaire, there was a postoperative improvement in quality of life (M = 11.34 ± 2.99) compared to the preoperative period (M = 20.8 ± 6.88). The improvement of quality of life 12 months after treatment occurred in all segments measured by both questionnaires. Conclusion. Orthodontic-surgical treatment of mandibular prognathism improves all oral functions, the appearance of the patient's face, and thus improves the quality of life.

Backround: The aim of this study was to evaluate the effects of probiotic yogurt containing Lactobacillus rhamnosus (LGG) on the microhardness and surface roughness of restorative dental materials commonly used in pediatric dentistry. Methods: Three materials were tested: conventional glass ionomer cement Fuji II, high-viscosity glass ionomer cement Fuji IX, and microhybrid composite resin Te Econom. The samples were prepared according to the manufacturers’ instructions, initially stored in distilled water, and subsequently immersed in probiotic yogurt. Microhardness was measured by the Vickers hardness test, and surface roughness was assessed by 3D profilometers. Results: Statistical analysis was performed using the Wilcoxon signed-rank test and the Kruskal–Wallis test. Exposure to probiotic yogurt resulted in increased microhardness for the resin-modified and high-viscosity glass ionomer cements, whereas the microhardness of the microhybrid composite resin decreased. The surface roughness increased for all the tested materials, with statistically significant differences observed in most groups (p < 0.05). Conclusions: These findings indicate that probiotic yogurt can alter the physical properties of restorative dental materials and highlight the importance of careful selection of preventive agents in pediatric dental practice. Further research is needed to clarify the long-term effects of probiotic preparations on dental restorations.