Clinical Research Directory

Quantitative In Vivo Monitoring of Early Erosion-Associated Enamel Optical Changes Using Swept-Source Optical Coherence Tomography.

This study aims to evaluate the ability of swept-source optical coherence tomography (SS-OCT) to detect early enamel optical changes associated with erosive tooth wear under clinically relevant in vivo conditions. The study also investigates whether salivary stimulation induced by sugar-free chewing gum influences enamel optical properties following repeated erosive challenges. A prospective, longitudinal, within-subject study with a fixed-sequence design was conducted. Twenty-two healthy adults aged 23-33 years participated after meeting predefined inclusion and exclusion criteria. All participants completed two sequential experimental phases separated by a two-day washout period. A fixed-order design (Phase A followed by Phase B) was selected to standardize erosive exposure and minimize variability during repeated intraoral OCT measurements. As an exploratory study, randomization was not performed. In both phases, participants underwent repeated erosive challenges using commercially available orange juice (pH 3.4). During each challenge, participants swished 25 mL of orange juice for 30 seconds followed by a 30-second rest interval, repeated continuously for 10 minutes (total exposure: 250 mL). Erosive challenges were performed three times daily at three-hour intervals over three consecutive days under investigator supervision. Phase A consisted of repeated erosive challenges without intervention. In Phase B, participants followed the identical erosive protocol but chewed sugar-free chewing gum for 15 minutes immediately after each erosive challenge to stimulate salivary flow and enhance natural buffering and remineralization mechanisms. All participants used standardized fluoridated toothpaste and soft-bristled toothbrushes beginning two days before the study and throughout the experimental period. Unstimulated salivary flow rate was measured before enrolment, and participants with salivary flow rates below 0.2 mL/min were excluded. The primary outcome measure was enamel integrated reflectivity (IR), quantified from SS-OCT A-scan analysis as an indicator of enamel optical changes associated with early demineralization. A commercially available swept-source OCT system equipped with an intraoral probe was used for image acquisition. The middle third of the labial surface of the maxillary right central incisor (tooth 11) served as the standardized imaging site. Custom acrylic positioning devices and anatomical landmarks were used to improve reproducibility of repeated measurements. SS-OCT imaging was performed at six standardized time points during each study day: baseline before the first erosive challenge (t1), after the first challenge (t2), after the second challenge (t3), after the third challenge (t4), following a three-hour rest period (t5), and the following morning after overnight salivary exposure (t6). Image acquisition parameters, drying procedures, and positioning were standardized for all participants. Integrated reflectivity values were calculated from predefined regions of interest using established OCT image analysis methods. Five adjacent A-scans were averaged to reduce signal noise. Statistical analyses included paired sample t-tests for predefined comparisons and linear mixed-effects modelling to evaluate longitudinal changes while accounting for repeated measurements within participants. Statistical significance was set at α = 0.05. The study was approved by the appropriate institutional ethics committee, and written informed consent was obtained from all participants before enrolment. The study complied with the principles of the Declaration of Helsinki. Findings are expected to provide evidence regarding the feasibility of SS-OCT as a non-invasive clinical tool for monitoring early erosive enamel changes and evaluating preventive interventions under clinically relevant oral conditions.

Obesity and Oral Diseases in Adult Patients

Overweight and obesity are among the major chronic disorders of the 21st century and one of the fastest growing health problems worldwide. Obesity is accompanied by a state of low-grade inflammation which may contribute to the occurrence of diabetes mellitus, cardiovascular disease, hypertension, stroke, and certain cancers. Furthermore, obesity has been associated with oral health problems as hyposalivation, dental caries and periodontitis. The management and treatment of obesity is outlined in clinical guidelines from American Association of Clinical Endocrinologists/American College of Endocrinology and European Association for the Study of Obesity. The cornerstone is life-style modification programs aiming to reduce energy intake and increase physical activity, referred to as conservative treatment. All patients must undergo a thorough systematic work-up. The work-up concludes in a final multi-disciplinary meeting with a concrete individualized plan on how sustained weight-loss is to be achieved; either by a non-surgical or a surgical approach (Bariatric surgery). Periodontitis is cited to be the sixth most prevalent chronic condition globally. The mechanisms by which obesity affects the periodontal tissues is poorly understood, and the understanding of the key role of adipocytes in the inflammatory response to infections is crucial in comprehending how periodontal disease susceptibility may be modified in obese individuals. The main objectives of the present research project are to explore the association between obesity and oral diseases and further, to assess how weight changes following non-surgical and surgical interventions of obese patients may affect the cariological and periodontal health status. Four hundred patients referred to the Obesity Centre at Haukeland University Hospital, Norway will consecutively be screened and invited to participate in this prospective cohort study. At baseline, detailed medical and oral data will be obtained from health forms, questionnaires, clinical examinations, and by consulting the patient's care team. Following baseline examination, all patients will undergo a thorough systematic work-up consisting av interviews and consultations concluding in a final multi-disciplinary individualized non-surgical or surgical treatment plan on how sustained weight-loss can be achieved. New sets of medical, oral, and molecular data will be collected at 3-, 12- and 18-month following non-surgical/surgical interventions.