An interventional study of Probiotics and Placebo tablet in Halitosis, Probiotics and Orthodontic Appliance Complication, sponsored by University of Athens. Completed at 1 site in Greece. Open to participants aged 12 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-12-10.
Sponsored by University of Athens · Not applicable, Interventional, and Prevention
Brackets, bands, ligatures and wires in patients receiving orthodontic treatment with fixed appliances are areas that trap food and impede oral hygiene. An ecological environment facilitating the growth of microorganisms (Actinobacillus, Bacteroides, Prevotella etc.) emerges in the mouth and may cause caries, enamel white spots, gingival inflammation and halitosis. Despite the use of specialized orthodontic brushes, interdental brushes, mouthwashes and topical fluorides, plaque removal remains inadequate in patients with fixed orthodontic appliances. On the other hand, patients undergoing orthodontic treatment with aligners have been found to have better oral hygiene because of less plaque accumulation in their mouth.
Probiotics are defined as non-pathogenic bacteria that can benefit the host's general health when taken in sufficient amounts through nutrition. Nowadays probiotics can be used to enhance oral health as they are found to reduce dental biofilm formation, prevent and decrease halitosis in children, adolescents and adults. To date, there are few randomized controlled trials (RCTs) examining the efficacy of oral probiotics in patients with fixed orthodontic appliances and none reporting the incidence of halitosis and the effect of probiotics in orthodontic patients wearing aligners.
The aim of the study is to investigate the effect of the oral probiotic Lactobacillus salivarius on oral hygiene indices and halitosis in patients wearing orthodontic braces and patients wearing orthodontic aligners. The study is a prospective, randomized, placebo-controlled, double blinded, with four parallel groups and an equal allocation ratio in all groups. Patients 12-18 years old undergoing fixed orthodontic treatment will be randomly allocated to probiotic group A (n=30) and placebo group B (n=30). Patients ≥18 years old wearing aligners (Invisalign™ ) will be randomly allocated to probiotic group C (n=30) and placebo group D (n=30). All participants will consume lozenges for one month. Assessments will be taken at baseline, at the end of the intervention and at a 2 month free-intervention follow-up. The outcome measures will be modified plaque index (PI), modified gingival index (GI) and halitosis-causing volatile sulfur compound (VSC) levels. Results will be announced at the end of the study.
93 studies on the registry are indexed under Halitosis; 17 are open to participants now.
This study's enrollment of 120 is above the median of 45 across 79 interventional studies indexed under Halitosis.
Browse Halitosis studies →University of Athens is the lead sponsor of 139 studies on the registry; 19 are open to participants now.
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Patients eligible for the trial must comply with all of the following at randomization:
Age ≥18 for the Invisalign™ group This age group represents the majority of patients seeking orthodontic with aligners (Invisalign™) regarding social status and other factors.
Exclusion Criteria:
Patients will be excluded for any of the following reasons:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
30 patients, age 12-18,with conventional brackets,will get Oral probiotics lozenges
Dietary Supplement: Probiotics
30 patients, age ≥18, Invisalign™ appliances,wil get Oral probiotics lozenges
Dietary Supplement: Probiotics
30 patients, age 12-18, conventional brackets,will get placebo lozenges
Dietary Supplement: Placebo tablet
30 patients, age ≥18, Invisalign™ appliances,will get placebo lozenges
Dietary Supplement: Placebo tablet
In our study oral probiotics Lactobacillus salivarius Oral S1 11 (Prodilac Oral, Frezyderm) will be tested in two Experimental groups
In order to avoid possible bias, probiotics will be compared with placebo lozenges/no probiotic in two Control groups
Modified Silness and Löe plaque index (PI-M)
The Silness and Löe index does not take into account the pattern of plaque accumulation in orthodontic patients. To overcome this problem, divided the tooth into mesial, distal, gingival, and incisal regions in relation to the bracket and scored plaque in each region using the four codes of the original index (0 to 3). The values are summed to obtain a total score, which ranges from 0 to 12 for each tooth. This modified index is recommended for patients with fixed orthodontic appliances because it acknowledges the usual effects of orthodontic appliances on plaque distribution and has much greater categorical discrimination.
Time frame: baseline-1 month
Modified Silness and Löe plaque index (PI-M)
The Silness and Löe index does not take into account the pattern of plaque accumulation in orthodontic patients. To overcome this problem, divided the tooth into mesial, distal, gingival, and incisal regions in relation to the bracket and scored plaque in each region using the four codes of the original index (0 to 3). The values are summed to obtain a total score, which ranges from 0 to 12 for each tooth. This modified index is recommended for patients with fixed orthodontic appliances because it acknowledges the usual effects of orthodontic appliances on plaque distribution and has much greater categorical discrimination.
Time frame: 1 month- 3 month
Modified Gingival index (GI-M)
The Gingival Index (GI) is a measure of the severity of gingivitis and is scored by measuring the amount of gingival inflammation, also considering redness and bleeding .
Time frame: baseline-1 month
Modified Gingival index (GI-M)
The Gingival Index (GI) is a measure of the severity of gingivitis and is scored by measuring the amount of gingival inflammation, also considering redness and bleeding.
Time frame: 1 month- 3 month
Halitosis/ VSCs levels
VSCs levels will recorded at each time point with the use of OralChromaTM. OralChromaTM is a portable gas chromatograph, which uses ambient air as a carrier gas and a semiconductor (In2O3) gas sensor to detect volatile sulphur compounds (VSCs), i.e. the concentrations of H2S, CH3SH and (CH3)2S.
Time frame: baseline-1 month
Halitosis/ VSCs levels
VSCs levels will recorded at each time point with the use of OralChromaTM. OralChromaTM is a portable gas chromatograph, which uses ambient air as a carrier gas and a semiconductor (In2O3) gas sensor to detect volatile sulphur compounds (VSCs), i.e. the concentrations of H2S, CH3SH and (CH3)2S.
Time frame: 1 month- 3 month
This study is completed, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.
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