Insomnia is a common and complex disorder, rooted in the dysregulation of circadian rhythms, impaired neurotransmitter function, and disturbances in sleep–wake homeostasis. While conventional hypnotics such as benzodiazepines and Z-drugs are effective in the short term, their use is limited by a high potential for dependence, cognitive side effects, and withdrawal symptoms. In contrast, melatonergic receptor agonists—melatonin, ramelteon, tasimelteon, and agomelatine—represent a pharmacologically targeted alternative that modulates MT1 and MT2 receptors, which are pivotal to the regulation of circadian timing and sleep initiation. Clinical evidence supports the efficacy of these agents in reducing sleep onset latency, extending total sleep duration, and re-aligning disrupted circadian rhythms, particularly among older individuals and patients with non-24 h sleep–wake disorders. Notably, agomelatine offers additional antidepressant properties through selective antagonism of the 5-HT_2C receptor in micromolar concentrations. In contrast, its agonistic activity at melatonergic receptors is observed in the low sub-nanomolar range, which illustrates the complexity of this drug’s interactions with the human body. All compounds reviewed demonstrate a generally favorable safety and tolerability profile. Accumulating evidence highlights that selected medicinal plants, such as chamomilla, lemon balm, black cumin, valeriana, passionflower and lavender, may exert relevant hypnotic or anxiolytic effects, thus complementing melatonergic strategies in the management of insomnia. This structured narrative review presents a comprehensive analysis of the molecular pharmacology, receptor affinity, signaling pathways, and clinical outcomes associated with melatonergic agents. It also examines their functional interplay with serotonergic, GABAergic, dopaminergic, and orexinergic systems involved in arousal and sleep regulation. Through comparative synthesis of pharmacokinetics and neurochemical mechanisms, this work aims to inform the development of evidence-based strategies for the treatment of insomnia and circadian rhythm sleep–wake disorders.

In contemporary dentistry, laser-based interventions have become one of the mainstays of care for patients with oral biofilm diseases, such as candidiasis, periodontal disease and peri-implantitis. The purpose of this study was to evaluate the effectiveness of Er:YAG laser (LightWalker, Ljubljana, Fotona, Slovenia) irradiation at varying irradiance levels (T1: 11.3 W/cm² and T2: 120.54 W/cm²) on microbial viability in single- and dual-species biofilm models, focusing on Candida albicans, Candida glabrata and Streptococcus mutans, to address challenges in managing complex oral biofilms in clinically relevant settings. The results showed substantial microbial reduction, with C. albicans being the most susceptible microorganism (93–99.9%), while C. glabrata exhibited marked resistance at higher irradiance levels. Interestingly, S. mutans demonstrated varying reductions based on the biofilm composition, highlighting the influence of microbial interactions. This study concluded that the Er:YAG laser effectively reduced biofilm viability, with its efficacy depending on the microbial composition and irradiance settings. These findings highlight the need for tailored erbium laser parameters to optimize clinical outcomes, underscoring the need for individualized polymicrobial biofilm management, particularly in periodontal and peri-implant therapies.

Background: Oral microbiota comprises a wide variety of microorganisms. The purpose of this study was to evaluate the effects of Nd:YAG laser with a 1064 nm wavelength on the in vitro growth of Candida albicans, Candida glabrata, and Streptococcus mutans clinical strains, as well as their biofilm. The study also aimed to determine whether the parameters recommended for photobiomodulation (PBM) therapy, typically used for tissue wound healing, have any additional antibacterial or antifungal effects. Material and Methods: Single- and dual-species planktonic cell solution and biofilm cultures of Streptococcus mutans, Candida albicans, and Candida glabrata were irradiated using an Nd:YAG laser (LightWalker; Fotona; Slovenia) with a flat-top Genova handpiece. Two test groups were evaluated: Group 1 (G-T1) exposed to low power associated parameters (irradiance 0.5 W/cm²) and Group 2 (G-T2) with higher laser parameters (irradiance 1.75 W/cm²). Group 3 (control) was not exposed to any irradiation. The lasers’ effect was assessed both immediately after irradiation (DLI; Direct Laser Irradiation) and 24 h post-irradiation (24hLI) of the planktonic suspension using a quantitative method (colony-forming units per 1 mL of suspension; CFU/mL), and the results were compared with the control group, in which no laser was applied. The impact of laser irradiation on biofilm biomass was assessed immediately after laser irradiation using the crystal violet method. Results: Nd:YAG laser irradiation with photobiomodulation setting demonstrated an antimicrobial effect with the greatest immediate reduction observed in S. mutans, achieving up to 85.4% reduction at the T2 settings. However, the laser’s effectiveness diminished after 24 h. In single biofilm cultures, the highest reductions were noted for C. albicans and S. mutans at the T2 settings, with C. albicans achieving a 92.6 ± 3.3% reduction and S. mutans reaching a 94.3 ± 5.0% reduction. Overall, the T2 settings resulted in greater microbial reductions compared to T1, particularly in biofilm cultures, although the effectiveness varied depending on the microorganism and culture type. Laser irradiation, assessed immediately after using the crystal violet method, showed the strongest biofilm reduction for Streptococcus mutans in the T2 settings for both single-species and dual-species biofilms, with higher reductions observed in all the microbial samples at the T2 laser parameters (p < 0.05) Conclusion: The Nd:YAG laser using standard parameters typically applied for wound healing and analgesic effects significantly reduced the number of Candida albicans; Candida glabrata; and Streptococcus mutans strains.

The oral microbiota consists of a diverse range of microorganisms, with Streptococcus spp. and Candida spp. frequently coexisting in oral infections. The aim of the study was to investigate the impact of Er:YAG (erbium-doped yttrium aluminum garnet) laser therapy, utilizing the PS04 fractional beam, on the in vitro growth and biofilm formation of clinical strains of Candida albicans, Candida glabrata and Streptococcus mutans. Singleand dual-species planktonic cultures and biofilms were exposed to an Er:YAG laser using a fractional PS04 handpiece. The effects of the laser were evaluated immediately after irradiation and 24 h post-irradiation by measuring colony-forming units per milliliter (CFU/mL). Biofilm biomass (singleand dual-species) was quantified using the crystal violet staining method. The study tested 2 sets of laser parameters: group 1 (T1): 1.5 W, 10 Hz, 30 s, 0.4 J/cm2, irradiance: 3.9 W/cm2; and group 2 (T2): 6.15 W, 10 Hz, 30 s, 1.6 J/cm2, irradiance: 16 W/cm2. Non-irradiated samples served as controls. The parameters were selected based on their frequent clinical use for snoring treatment and facial rejuvenation. Candida albicans exhibited a significantly greater reduction under T2 settings in comparison to T1 (85.3 ±1.2% vs. 43.9 ±4.5%, respectively; p = 0.006) within single-species biofilms. For C. glabrata, a significant reduction was observed under T1 parameters (69.8 ±14.9%). Furthermore, S. mutans demonstrated a significantly higher reduction at T2 settings (97.1 ±0.6%) compared to T1 settings (81.1 ±19.6%), with statistically significant differences noted between S. mutans and both C. albicans and C. glabrata under T1, as well as between S. mutans and C. glabrata under T2. In dual-species biofilms, T2 fluence led to greater reductions in C. glabrata, S. mutans and C. albicans in mixed cultures (p < 0.05). The Er:YAG laser, when used in conjunction with the PS04 handpiece, demonstrated a substantial reduction in the biofilms of C. albicans and C. glabrata. Higher fluence maintained reductions over a 24-h period, particularly in the case of C. glabrata and S. mutans. This study highlights the antifungal potential of low-fluence laser settings that are commonly used in facial aesthetic procedures and snoring treatment.

Rosacea is a chronic inflammatory skin disease characterized by erythematous, papular, and pustular lesions. Treatment for rosacea is tailored to the type and severity of lesions and the individual needs of the patient. The primary therapy involves topical and systemic treatments. Laser therapy is also an effective method. This review summarizes current knowledge on the application of pulsed dye lasers (PDLs), potassium titanyl phosphate (KTP) lasers, intense pulsed light (IPL), neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers, carbon dioxide (CO₂) lasers, and erbium-doped yttrium aluminum garnet (Er:YAG) lasers in the treatment of rosacea. Research confirms that the PDL remains the gold standard, demonstrating excellent clinical efficacy. The KTP and IPL lasers provide comparable outcomes, with relatively fewer adverse effects. Due to its greater depth of penetration, the Nd:YAG laser is used to treat lesions in the deeper layers of the skin. In advanced forms of rosacea, such as rhinophyma, ablative lasers, including CO₂ and Er:YAG, are employed. This review summarizes the mechanisms of action, therapeutic applications, and adverse effects associated with the use of various laser types in the management of rosacea.

Background: In psychiatry, gambling is classified as an addiction-related disorder and is characterized by a persistent, problematic pattern of behaviour that leads to significant distress and functional impairment. This study aims to explore the prevalence, underlying motivations, and potential academic impact of gambling behaviours among medical students in Poland. Methods: An anonymous online survey was conducted among students from multiple medical universities across Poland. Participants completed a sociodemographic questionnaire and the South Oaks Gambling Screen (SOGS). Respondents who reported any past or current gambling activity were additionally asked about their motivations and potential academic consequences. Results: The study included 281 participants. Active or past gambling was reported by 55% of respondents, with men significantly more likely to gamble currently. Women were predominantly non-problem gamblers, whereas men more often scored within the “some problems” range on the SOGS. Motivations also differed: women emphasised financial gain, while men cited fun, socializing, and competition. Lottery and scratch cards were most popular overall, though men preferred skill-based and casino activities. Conclusions: Although participants showed relatively low levels of gambling involvement, their risk of developing pathological gambling was comparable to that of the general population. Gender influenced involvement in different gambling patterns.