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

Completed

• Conditions: Gingivitis; Dental Plaque
• Interventions: Other: Control Dentifrice; Other: Sodium bicarbonate

• Registration Number: NCT03703245
• Lead Sponsor: GlaxoSmithKline

Brief Summary

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.

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 Timeline

• Study First Submitted: 2018-09-14
• Study First Submitted QC: 2018-10-03
• Study First Posted: 2018-10-11
• Study Start: 2019-04-17
• Primary Completion: 2019-11-11
• Study Completion: 2019-11-11
• Status Verified: 2020-01
• Last Update Submitted: 2020-01-15
• Last Update Posted: 2020-01-18

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 1601

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 & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Control Dentifrice	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.
Experimental Dentifrice	Sodium bicarbonate	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.

Primary Outcome Measures

Name	Time	Method
Mean number of Bleeding Sites over 24 weeks	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.

Secondary Outcome Measures

Name	Time	Method
Mean Turesky modification of the Quigley Hein plaque index (TPI) over 24 weeks	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.
Mean Modified Gingival Index (MGI) over 24 weeks	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.
Mean Bleeding Index (BI) over 24 weeks	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.

Trial Locations

Locations (1)

GSK Investigational Site; 🇬🇧 Weybridge, Surrey, United Kingdom