Pooled Analysis of Clinical Data From Six GSK Studies to Investigate the Efficacy of a Dentifrice Containing 67% Weight by Weight (w/w) Sodium Bicarbonate on Gingivitis and Plaque Accumulation

A Post-hoc Pooled Analysis of GSK CH Clinical Data Investigating the Efficacy of a Dentifrice Containing 67% w/w Sodium Bicarbonate on Gingivitis and Plaque Accumulation

The aim of this analysis was to pool data from 6 GSK studies with similar clinical design to investigate the overall efficacy of a test dentifrice containing 67% w/w sodium bicarbonate in the treatment of gingivitis and plaque accumulation after 6, 12 and 24 weeks of twice-daily brushing at home relative to a negative control dentifrice.

The pooled analysis was planned and conducted after completion of all six independent studies.

Study Overview

• Status: Completed
• Conditions: Gingivitis; Dental Plaque
• Intervention / Treatment: Other: Sodium bicarbonate; Other: Control Dentifrice

Detailed Description

This pooled analysis was performed on data collated from six GSK studies that provide efficacy data supporting the twice-daily use of a dentifrice containing 67% w/w sodium bicarbonate in the management of pre-existing gingivitis, and plaque accumulation. Six studies that were chosen for inclusion in the pooled analysis were single-center, examiner-blind, 2 to 3 treatments, parallel group, stratified and randomized clinical study. In all studies, participants entered the screening period during which eligibility for the study was determined. The participants included male and non-pregnant, non-lactating female subjects at least 18 years of age with pre-existing gingivitis as determined by an appropriately qualified clinical examiner. Participants meeting the inclusion criteria entered an acclimatization period in order to minimize any potential placebo response. Participants were randomized into treatments, parallel group, stratified and randomized clinical studies twice daily at home for 6, 12 and 24 weeks and participants returned to the site. Participants underwent a full OST examination and the recording of any Adverse Events (AEs). Participants then underwent Modified Gingival Index (MGI), Bleeding Index (BI), Gingival Severity Index (GSI) followed by dental plaque assessments.

• Study Type: Observational
• Enrollment (Actual): 1601

Contacts and Locations

Study Locations

• United Kingdom
  • Surrey
    • Weybridge, Surrey, United Kingdom
      • GSK Investigational Site

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years to 61 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Retrospective pooled studies include healthy male and non-pregnant, non-lactating female subjects at least 18 years of age, with pre-existing gingivitis as determined by an appropriately qualified clinical examiner

Description

Inclusion Criteria:

• Clinical studies conducted by GSK CH, including access to study protocols, study reports, and access to individual information sources/ study data.
• Study design and subject inclusion criteria in agreement with guidelines to assess gingivitis efficacy such as inclusion of a pre-treatment full-mouth prophylaxis, Subject eligibility (>20 bleeding sites and mild-moderate gingivitis at Screening);Comparable indices of gingivitis and plaque accumulation; a treatment for a 67% w/w sodium bicarbonate dentifrice; Repeat brushing for at least a period of 4 weeks or 4-6 weeks.

Exclusion Criteria: Not Applicable

Study Plan

How is the study designed?

Design Details

• Observational Models: Other
• Time Perspectives: Retrospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Experimental Dentifrice; Participants were advised to brush their teeth twice daily with a full strip of experimental dentifrice containing 67% w/w sodium bicarbonate in 3 studies and additionally 62% w/w sodium bicarbonate in 3 studies covering the entire head of the toothbrush for 1 minute.	Other: Sodium bicarbonate; Experimental dentifrice containing 67% w/w sodium bicarbonate in 3 studies and additionally 62% w/w sodium bicarbonate in 3 studies.
Control Dentifrice; Participants were advised to brush their teeth with control dentifrice containing 0% w/w sodium bicarbonate covering the entire head of the toothbrush for 1 minute.	Other: Control Dentifrice; Negative control dentifrice containing 0% w/w sodium bicarbonate

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean number of Bleeding Sites over 24 weeks	Number of gingival bleeding sites were measured as BI via a single examiner using a color coded periodontal probe. The probe was gently inserted approximately 1 millimeter (mm) into the gingival crevice. A moderate pressure was used whilst sweeping from interproximal to interproximal along the sulcular epithelium. The BI scoring system used to measure bleeding sites is as follows: 0= No bleeding after 30 seconds; 1= Bleeding upon probing after 30 seconds; 2= Immediate bleeding observed. A bleeding site was considered as a BI score of 1 or 2. This measure will be analyzed and summarized over all sites and at the tooth site level.	Over 24 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Bleeding Index (BI) over 24 weeks	The BI was performed by a single examiner using a color coded periodontal probe. The probe was inserted approximately 1 mm into the gingival crevice. A moderate pressure was used whilst sweeping from interproximal to interproximal along the sulcular epithelium. The BI scoring system to be used is as follows: 0= No bleeding after 30 seconds; 1= Bleeding upon probing after 30 seconds; 2= Immediate bleeding observed. This measure will be analyzed and summarized over all sites and at the tooth site level.	Over 24 weeks
Mean Modified Gingival Index (MGI) over 24 weeks	The MGI was assessed on facial and lingual surfaces at two sites on each tooth (papillae and margin).The scoring of MGI was performed by a single examiner. The MGI scoring system is as follows:0=absence of inflammation;1=mild inflammation; slight change in color, little change in color;little change in texture of any portion of the marginal or papillary gingival unit;2=mild inflammation; criteria as above but involving the entire marginal or papillar gingival units;3=moderate inflammation; glazing, redness, edema, and/or hypertrophy of the marginal or papillary gingival unit;4=severe inflammation; marked redness, edema and/or hypertrophy of the marginal or papillary gingival unit, spontaneous bleeding, congestion, or ulceration.This measure will be analyzed and summarized over all sites and at the tooth site level.	Over 24 weeks
Mean Turesky modification of the Quigley Hein plaque index (TPI) over 24 weeks	The dental examiner used the TPI to assess plaque on all gradable teeth. The plaque was first disclosed using a dye solution. Participants then rinsed with disclosing solution according to instructions. They had expectorated and rinsed with 10 mL of water for 10 seconds and expectorated again. Plaque was assessed with each tooth being divided into 6 areas including the mesiofacial, facial, distofacial, mesiolingual, lingual and distolingual surfaces. Disclosed plaque was scored as follows: 0= No plaque; 1= Slight flecks of plaque at the cervical margin of the tooth; 2= A thin continuous band of plaque (1 mm or smaller) at the cervical margin of the tooth; 3= A band of plaque wider than 1 mm but covering less than 1/3 of the crown of the tooth; 4= Plaque covering at least 1/3 but less tan 2/3 of the crown of the tooth; 5= Plaque covering 2/3 or more of the crown of the tooth.This measure will be analyzed and summarized over all sites and at the tooth site level.	Over 24 weeks

Collaborators and Investigators

• Sponsor: GlaxoSmithKline

Study record dates

Study Major Dates

• Study Start (Actual): April 17, 2019
• Primary Completion (Actual): November 11, 2019
• Study Completion (Actual): November 11, 2019

Study Registration Dates

• First Submitted: September 14, 2018
• First Submitted That Met QC Criteria: October 3, 2018
• First Posted (Actual): October 11, 2018

Study Record Updates

• Last Update Posted (Actual): January 18, 2020
• Last Update Submitted That Met QC Criteria: January 15, 2020
• Last Verified: January 1, 2020

More Information

Terms related to this study

• Keywords: Plaque Accumulation
• Additional Relevant MeSH Terms: Infections; Stomatognathic Diseases; Periodontal Diseases; Mouth Diseases; Gingival Diseases; Tooth Diseases; Dental Deposits; Gingivitis; Dental Plaque
• Other Study ID Numbers: 209509

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No