Clinical Research Directory

Microbiological and Clinical Effects of Pre- and Probiotics in Non-Surgical Periodontal Therapy

Periodontitis is a prevalent chronic inflammatory disease driven by a dysbiotic oral biofilm and a dysregulated host immune response. Standard non-surgical periodontal therapy (NSPT) is primarily mechanical and, in selected cases, may be accompanied by antiseptics or systemic antibiotics. Targeted modulation of the oral microbiome ("microbiome engineering") is currently not part of routine periodontal care due to limited high-quality evidence. PROPARO is a single-center, randomized, controlled pilot study designed to assess whether adjunctive oral supplementation with a probiotic containing Limosilactobacillus reuteri (commercial dietary supplement lozenge) alone or combined with vitamin B12 (commercial dietary supplement drops) is associated with changes in supragingival and subgingival oral microbiome composition during guideline-concordant NSPT compared with standard care alone. Participants with Stage III or IV periodontitis will be randomized 1:1:1 to: (1) NSPT/SPT without supplementation (control), (2) NSPT/SPT plus probiotic lozenges for 3 months, or (3) NSPT/SPT plus probiotic lozenges and vitamin B12 drops for 3 months. The primary outcome is change in oral microbiome composition and structure (supragingival and subgingival), assessed using 16S rDNA-based profiling and metagenomic sequencing approaches. Secondary outcomes include clinical periodontal parameters (e.g., probing depth, clinical attachment level, bleeding on probing), oral hygiene/gingival indices, dental status, and participant-level ecological covariates (diet quality, perceived stress, physical activity). Sampling and assessments are aligned with routine care time points from baseline through supportive periodontal therapy follow-up (up to 12 months). This pilot trial aims to generate feasibility and effect-size estimates to inform future confirmatory studies and potential translation into guideline-based periodontal care.

3-Month Clinical Trial of Liquid S-PRF in Periodontal Debridement for Periodontitis Stages II-IV

What is the purpose of this study? This study is to investigate the effect of a processed blood product in healing after treatment for gum disease. In addition to scaling \& root debridement (deep cleaning) that is the standard treatment for periodontitis, this study will test the effectiveness of patient's processed blood in improving healing of diseased gums. What are the procedures to be followed? First, all patients will undergo dental check-up and X-ray imaging for suitability as a participant for the project. For participants who are eligible and included into study, upper \& lower jaws models will be made, and each will be given oral care kit \& instructions. The next appointment will be given for scaling \& root debridement with local numbing agent in one day. Towards the end of the treatment, a small amount (20 mℓ) of blood will be collected and spun to produce liquid platelet-rich fibrin that is then used to flush the treated gum pockets in half of the mouth. For the treated gum pockets in the opposite half of the mouth, sterile salt water (saline) will be used instead for comparison. Then, follow-up appointments are at monthly intervals until 3 months. Who should enter the study? Symptoms of gum disease include bleeding and/or receding gums, tooth/teeth appearing longer or feeling shaky/loose/weak, formation of large amount of calculus and/or black/empty space between teeth, frequent/recurrent gum swelling/pus, and/or bad breath.

The Effect Of Enamel Matrix Derivatives On Gingival Tissue Thickness

Scientists do research to answer important questions which might help change or improve the way we do things in the future. The investigators know that using Enamel Matrix Derivatives results in thicker gum tissues around teeth. This study will test to see if using EMD around implants results in thicker gum tissues around implants.

Full Mouth Ultrasonic Debridement Carried Out With Either Piezoelectric or Magnetostrictive Device

The treatment of periodontitis requires the removal of dental biofilm through both professional mechanical plaque removal and at-home oral hygiene practices. This study aims to compare clinical and psychological outcomes following professional treatment using either piezoelectric or magnetostrictive ultrasonic devices.

A Chitosan Brush and Enamel Matrix Derivative for Non-surgical Treatment of Furcations

Patients diagnosed with stage III or IV periodontitis who exhibit mandibular first or second molars with Class II, Subclass A, or B buccal and/or lingual mandibular furcation defects (horizontal probing depth of ≥ 3 mm ) will be recruited. Patients diagnosed with stage III or IV periodontitis who exhibit maxillary first or second molars with Class II, Subclass A, or B buccal furcation defects (horizontal probing depth of ≥ 3 mm ) if furcation involvement on the palatal side (mesiopalatal and distopalatal) does not exceed Class 1 will be recruited. This study will be a prospective, randomized, single-blinded, controlled clinical trial with a split-mouth design. Patients will be recruited from the clinics of the Riga Stradiņš University Institute of Stomatology of Riga, Latvia. Before the baseline treatment, all patients who meet the inclusion criteria will be given detailed oral hygiene instructions and motivation. Patients' furcation defects in each quadrant will be randomly allocated at a 1:1 ratio to either the application of Oscillating Chitosan Brush with Enamel Matrix Derivatives (test group) or Oscillating Chitosan Brush alone (control group). Non-surgical periodontal treatment of furcation defects on the test side will be performed through the application of Oscillating Chitosan Brush with Enamel Matrix Derivatives and on the control side with Oscillating Chitosan Brush alone. The re-evaluation of periodontal status will be performed 12 weeks following the baseline treatment. Biofilm samples and gingival crevicular fluid (GCF) samples will be taken at the baseline and at 4 weeks.

Changes in Microbial Status From Dentate, Edentulous and After Dental Implant Placement

The objectives of this study are to analyze the oral microbiome modulations occurring during the transition from partial (with some residual teeth) to full edentulous (without remaining teeth) status and implant placement in subjects affected by severe periodontitis; to evaluate if microbiome changes in relation to the used of different implant material/surface; and to assess the variance of the changes to determine the sample size for future longitudinal prospective studies.

Impact of Smoking on Salivary Interleukin (IL)-39, IL-41, IL-1β, TNF-α Levels in Periodontal Disease

The goal of this observational study is to evaluate if the measurement of salivary Interleukin (IL)-39, IL-41, IL-1Beta(β), and Tumor necrosis factor-alpha (TNF-α) levels can aid in the early diagnosis of periodontitis in patients with varying periodontal conditions, both smokers and non-smokers. The main questions it aims to answer are: Can salivary IL-39, IL-41, IL-1β, and TNF-α levels be used as biomarkers for the early diagnosis of periodontitis? How do IL-41 and IL-39 levels correlate with smoking status in periodontal healthy and periodontitis patients? Researchers will compare the salivary biomarker levels between smokers and non-smokers to see if smoking affects these levels. Participants will: Provide salivary samples for biomarker analysis. Undergo a comprehensive periodontal examination to determine their periodontal status.

Non-surgical Periodontal Treatment in Smokers on SIRT-1, NLRP3 Inflammasome and LncRNAs

The goal of this observational is to analyze the relationship between levels of interleukin-18 (IL-18), interleukin (IL-1β), Tumor Necrosis Factor-alpha (TNF-α), interleukin-10 (IL-10), transforming growth factor beta (TGF-β), Nucleotide-binding oligomerization domain -like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC), caspase-1, Sirtuin 1 (SIRT-1), Long noncoding RNA (lncRNA) small nucleolar RNA host gene 5 (SNHG5), and maternally expressed gene 3 (MEG3) in saliva, serum, and peripheral mononuclear blood cell (PMBC)in patients with periodontitis and smokers, to examine the changes in these biomarkers after non surgical periodontal treatment (NSPT), and to evaluate potential confounders that may mediate this relationship. The main questions it aims to answer are: question 1: Is there a relationship between the biomarkers mentioned above and periodontitis and smoking? question 2:How do the above-mentioned biomarkers change after NSPT in smokers and non-smokers?