Objective: To determine the physiologic changes of salivary flow rate, pH, and buffer capacity and the levels of Streptococcus mutans and Lactobacillus spp in patients undergoing fixed orthodontic treatment. Materials and Methods: The study included 23 patients scheduled for fixed orthodontic therapy. All subjects received equal braces, bands, and brackets, bonded with the same material. Stimulated saliva samples were taken before placement of the appliance, and at weeks 6, 12, and 18 during the therapy. Salivary flow rate and salivary pH were measured, and the salivary buffer capacity was determined. Saliva samples were cultivated on selective microbial agar for microorganism detection. Results: A significant (P < .05) increase in stimulated salivary flow rate and salivary pH was found. The salivary levels of S mutans and Lactobacillus spp also inscreased significantly (P < .05), and the major peak was at week 12 of fixed orthodontic therapy. Conclusion: The 6th to 12th week of orthodontic therapy is the period of the most intensive intraoral growth of S mutans and Lactobacillus spp and a time of very intensive salivary functions and physiologic response.

The aim of this cross-sectional study was to objectively assess the salivary flow rate and composition and periodontal inflammation in obstructive sleep apnoea (OSA) patients. The subjects, who underwent whole-night polysomnography or polygraphy, were referred for saliva sampling and periodontal examination. According to the severity of OSA based on the Apnoea Hypopnea Index (AHI) value, the subjects were classified into groups: no OSA (AHI < 5; N = 17), mild to moderate OSA (AHI 5–29.9; N = 109), and severe OSA (AHI > 30; N = 79). Salivary flow rate, pH, salivary electrolytes, and cortisol were measured from collected saliva samples. Periodontal examination included assessment of the number of teeth, dental plaque, bleeding on probing and periodontal measurements: gingival recession, probing pocket depth, clinical attachment level (CAL) and periodontal inflamed surface area (PISA) score. There were no significant differences in salivary flow rate, salivary pH, salivary electrolyte concentrations or electrolyte ratios among the groups classified according to the severity of OSA. However, subjects without OSA had higher salivary cortisol concentrations than OSA groups (p < 0.001). Increased plaque scores were associated with a higher AHI (r = 0.26; p = 0.003). According to the salivary flow rate, subjects with hyposalivation and reduced salivation had higher concentrations of salivary electrolytes and lower salivary pH than subjects with normal salivation. Subjects with hyposalivation had an increased Mg/PO₄ ratio (p < 0.001) and a reduced Ca/Mg ratio (p < 0.001). Furthermore, subjects with severe OSA tended to have higher CALs and plaque volumes. In conclusion, under pathological conditions, such as OSA, multiple interactions might impact salivary flow and electrolyte composition. Complex interrelationships might affect the integrity of oral health, especially considering OSA severity, inflammation, concomitant diseases and medications.

Antibiotic prophylaxis in dentistry has been recommended for different groups of patients, such as patients with impaired immunologic function, patients at risk of developing infective endocarditis or prosthetic joint infection, patients previously exposed to high-dose irradiation of the head and neck regions, and patients receiving intravenous bisphosphonate and antiangiogenic treatment. The guidelines have been changed over the years, and the list of medical conditions requiring antibiotic prophylaxis has been shortened considerably in the context of antibiotic resistance and unnecessary antibiotic prescription.

The study aimed to investigate the rechargeability of ion-releasing dental material specimens immersed in distilled water for 25 months, which depleted their ion-releasing ability. Four restorative dental materials (alkasite composite, giomer, glass-ionomer, and composite material) presented with 24 specimens were studied after topical treatment with a concentrated fluoride gel. The effect of resin coating on the ion uptake and release was investigated on additional 42 specimens of restorative dental materials with coatings. The composite materials were coated with two adhesive systems, whereas the glass-ionomer was coated with the special coating resin. After topical fluoride exposure, ion release and specimen mass were measured at 1, 2, 3, 4, 5, 6, 7, and 14-day intervals using an ion-selective electrode and an analytical balance, respectively. The cumulative fluoride levels for the uncoated specimens of alkasite composite were significantly higher than those of giomer and glass-ionomer cement, with no statistically significant difference between the latter two materials. The conventional composite had the lowest cumulative concentration of fluoride ions (p < 0.05). The adhesive systems affected the fluoride recharge and reduced the ion concentrations absorbed by the specimens. Specimens coated with universal adhesive showed significantly higher ion release compared to universal fluoride-releasing adhesive or special coating resin for glass-ionomers (p < 0.05). No statistically significant change in specimen mass was observed during the 14-day period. Surface coating with adhesive systems as well as special coating resin for glass-ionomers affects the fluoride recharge process.

While smoking is recognized as one of the factors for the development and progression of periodontal diseases, a relation between the composition of the subgingival microbiota and smoking is yet to be elucidated. The aim of this study was to investigate the prevalence of subgingival bacteria in young smokers and non-smokers without clinical signs of periodontal disease. In this cross-sectional study, performed at the Department of Pharmacology, School of Dental Medicine, University of Zagreb, we enrolled 32 periodontally healthy smokers and 32 non-smokers, aged 25–35 years old. The number of oral bacteria and the prevalence of particular bacteria were assessed for each subject. Subgingival plaque samples were collected with sterile paper points from two first molars for microbiological analyses with MALDI-TOF mass spectrometry. In smokers, a significantly higher prevalence of Actinomyces odontolyticus was observed compared to non-smokers, and a significantly lower prevalence of Streptococcus sanguinis was observed compared to non-smokers. Smoking affects the composition of subgingival microbiota, either via depletion of beneficial bacteria or the increase in pathogenic bacteria.