The effect of MI Varnish™ on the development of tooth decay in 6- and 12-year-old children in Riga, Latvia

ISRCTN ISRCTN10584414
DOI https://doi.org/10.1186/ISRCTN10584414
Secondary identifying numbers U1111-1275-4126
Submission date
07/03/2022
Registration date
07/03/2022
Last edited
14/08/2023
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Oral Health
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
Tooth decay (dental caries) is damage to a tooth that can happen when decay-causing bacteria in your mouth make acids that attack the tooth's surface, or enamel. This can lead to a small hole in a tooth, called a cavity. If tooth decay is not treated, it can cause pain, infection, and even tooth loss.
Fluoride varnish (FV) is considered safe, well accepted by children, and easily delivered by health practitioners. A therapeutic product combining fluoride and CPP-ACP in a varnish (MI Varnish™; GC corporation, Japan) was developed few years ago demonstrating its caries prevention potential.
The aim of the present study was to investigate the effect of MI Varnish™ on caries increment in 6- and 12-year old children in Riga, Latvia within 36 months.

Who can participate?
6- and 12-year old children, inhabitants of Riga, who visited the Institute for dental treatment.

What does the study involve?
All children were recruited into the study during their regular dental check-ups in a random manner. On meeting the examiner, odd numbers of both age groups were recruited into the Varnish group (6 years old into group 1; 12 years old into group 3), while even numbers were recruited into the control groups (6 years old into group 2; 12 years old into group 4).
Following the baseline caries examination, the treatment groups (group 1 & 3) received the application of MI Varnish™ (5% sodium fluoride GC Corp., Tokyo, Japan), while the control groups (Group 2 & 4) did not have varnish applied.
Groups 1 & 3 had the varnish applied every 3 months for 3 years.
All subjects received general oral hygiene instruction at baseline and at the last visit.

What are the possible benefits and risks of participating?
Benefits: Participants will receive more frequent checkups for dental caries.
Risks: None

Where is the study run from?
Riga Stradins University (Latvia)

When is the study starting and how long is it expected to run for?
December 2015 to March 2020

Who is funding the study?
Investigator initiated and funded

Who is the main contact?
Dr Jekaterina Gudkina, jekaterina.gudkina@rsu.lv

Contact information

Dr Jekaterina Gudkina
Scientific

20 Dzirciema street
Riga
LV-1010
Latvia

ORCiD logoORCID ID 0000-0001-5135-1538
Phone +371 29486408
Email jekaterina.gudkina@rsu.lv

Study information

Study designSingle-center interventional randomized controlled trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Dental clinic, University/medical school/dental school
Study typePrevention
Participant information sheet 41306 PIS control group.pdf
Scientific titleThe effect of MI Varnish™ on dental caries among 6- and 12-year-old children in Riga, Latvia. A 3-year study.
Study objectivesQuarterly application of MI Varnish™ could reduce caries increment in children in Riga, Latvia.
Ethics approval(s)Approved 17/12/2015, RSU Ethics Committee (16 Dzirciema str., Riga, Latvia; +371 67326203; pek@rsu.lv), ref: not provided
Health condition(s) or problem(s) studiedDental caries development
InterventionCurrent interventions, as of 04/04/2022:

All children were recruited into the study during their regular dental check-ups in a random manner as follows. During the visit, children are listed in serial numbers in the order of their arrival time at the reception desk of the RSU Institute of Stomatology. On meeting the examiner, odd numbers of both age groups were recruited into the Varnish group (6 years old into group 1; 12 years old into group 3), while even numbers were recruited into the control groups (6 years old into group 2; 12 years old into group 4).

Following the baseline caries examination, the treatment groups (groups 1 & 3) received the application of MI Varnish™ (5% sodium fluoride GC Corp., Tokyo, Japan), while the control groups (Group 2 & 4) did not have varnish applied. Application of MI varnish was performed in accordance with the manufacturer’s instruction. The post-varnish instruction as provided by the manufacturer was given to all children and their parents. Neither the children nor their parents in the Varnish (Groups 1 and 3) were informed about the name of varnish (MI Varnish) used, and the manufacturer’s name.

Subsequently, subjects in the treatment groups (group 1 & 3) were recalled every 3 months for re-application of varnish for the 36 months study period. Subjects in the control groups (Group 2 & 4) again received only oral hygiene instruction. Children and their parents were informed about the precise time of attending the dentist by using the mobile telephone number provided at a baseline. At the baseline and 3 monthly MI Varnish re-application visits, teeth were brushed with non-fluoridated professional toothpaste (Zircate Prophy Paste; Dentsply Caulk, Germany) and then MI Varnish™ (GC Corp., Tokyo, Japan) was reapplied on all tooth surfaces.

_____

Previous interventions:

All children were recruited into the study during their regular dental check-ups in a random manner as follows. During the visit, children are listed in serial numbers in the order of their arrival time at the reception desk of the RSU Institute of Stomatology. On meeting the examiner, odd numbers of both age groups were recruited into the Varnish group (6 years old into group 1; 12 years old into group 3), while even numbers were recruited into the control groups (6 years old into group 2; 12 years old into group 4).

Following the baseline caries examination, the treatment groups (groups 1 & 3) received the application of MI Varnish™ (5% sodium fluoride GC Corp., Tokyo, Japan), while the control groups (Group 2 & 4) did not have varnish applied. Application of MI varnish was performed in accordance with the manufacturer’s instruction. The post-varnish instruction as provided by the manufacturer was given to all children and their parents. Neither the children nor their parents in the Varnish (Groups 1 and 3) were informed about the name of varnish (MI Varnish) used, and the manufacturer’s name.

Subsequently, subjects in the treatment groups (group 1 & 3) were recalled every 3 months for re-application of varnish and reinforcement of the oral hygiene instructions for the 36 months study period. Subjects in the control groups (Group 2 & 4) again received only oral hygiene instruction. Children and their parents were informed about the precise time of attending the dentist by using the mobile telephone number provided at a baseline. At the baseline and 3 monthly MI Varnish re-application visits, teeth were brushed with non-fluoridated professional toothpaste (Zircate Prophy Paste; Dentsply Caulk, Germany) and then MI Varnish™ (GC Corp., Tokyo, Japan) was reapplied on all tooth surfaces.
Intervention typeOther
Primary outcome measureCurrent primary outcome measure as of 04/04/2022:

Measured at baseline and 36 months:
1. Caries increment measured using the caries assessment criteria of the ICDAS II (https://www.iccms-web.com)
2. Oral hygiene indices measured using the Green-Vermillion oral hygiene index (G-V index)
3. Dietary habits measured using a questionnaire for children and/or their parents about snacking habit, intake of chocolates, carbonated soft or sport drinks during the day, number of tea spoons of sugar (t.s.) per cup of tea, and the number of cups of tea consumed daily

_____

Previous primary outcome measure:

Measured at baseline and every 3 months for 36 months:
1. Caries increment measured using the caries assessment criteria of the ICDAS II and digital bitewing (BW) X-rays
2. Oral hygiene indices measured using the Green-Vermillion oral hygiene index (G-V index)
3. Dietary habits measured using a questionnaire for children and/or their parents about snacking habit, intake of chocolates, carbonated soft or sport drinks during the day, number of tea spoons of sugar (t.s.) per cup of tea, and the number of cups of tea consumed daily
Secondary outcome measuresThere are no secondary outcome measures
Overall study start date17/12/2015
Completion date13/03/2020

Eligibility

Participant type(s)Healthy volunteer
Age groupChild
Lower age limit6 Years
Upper age limit12 Years
SexBoth
Target number of participantsA total number of 64 children per group has been estimated to detect a difference between groups, with a two-tailed α of 0.05 and a (1-β) of 0.80, for a comparison of 2 independent means if there was an absolute difference of 5 units outcome measure and standard deviation of 9 units. The drop out was calculated as 25%. Sample size was calculated as follows: Type I error = 5% implies constant 1,96 Type 2 error = 20% implies constant 0,84 N=2*[((1,96+0,84)*SD)/(difference)]2 = 2*(2,8*9/5)2=50,8032~51 N(with drop-out)=1,25* 51 = 63,75 ~ 64 children per each group.
Total final enrolment260
Key inclusion criteriaHealthy volunteers at the age of 6 and 12 years, living in Riga.
Key exclusion criteria1. Children and/or their parents refused to participate in the study
2. The families moved away from Riga
3. Children or parents did not answer the 3 telephone calls confirming their appointments
4. Orthodontic braces
5. General ill-health within the study period
Date of first enrolment01/02/2016
Date of final enrolment12/03/2017

Locations

Countries of recruitment

  • Latvia

Study participating centre

RSU Institue of Stomatology
20, Dzirciema street
Riga
LV-1010
Latvia

Sponsor information

Riga Stradiņš University
University/education

16 Dzirciema street
Riga
LV-1010
Latvia

Phone +371 60002571
Email tsk@rsu.lv
Website http://www.rsu.lv/eng/
ROR logo "ROR" https://ror.org/03nadks56

Funders

Funder type

Other

Investigator initiated and funded

No information available

Results and Publications

Intention to publish date31/12/2022
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryAvailable on request
Publication and dissemination planPlanned publication in a high-impact peer-reviewed journal.
IPD sharing planThe datasets generated during and analyzed during the current study will be available upon request from Dr Jekaterina Gudkina (j.gudkina@inbox.lv).

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Protocol file 07/03/2022 No No
Abstract results 05/07/2021 04/04/2022 No No
Participant information sheet control group 04/04/2022 No Yes
Participant information sheet intervention group 04/04/2022 No Yes
Results article 01/06/2022 24/06/2022 Yes No
Results article Effects on different tooth surfaces 07/08/2023 14/08/2023 Yes No

Additional files

41306 Protocol.pdf
41306 PIS control group.pdf
control group
41306 PIS intervention group.pdf
intervention group

Editorial Notes

14/08/2023: Publication reference added.
01/08/2022: The IPD sharing statement has been added.
24/06/2022: Publication reference added.
04/04/2022: The following changes were made to the trial record:
1. The primary outcome measure was changed.
2. The participant information sheets were uploaded as additional files.
3. The total final enrolment was added.
4. Publication reference added.
5. The interventions were changed.
07/03/2022: Trial's existence confirmed by RSU ethical committee.