Clinical Efficacy Evidence: Reducing Plaque, Gingivitis, Staining and Calculus

While patient preference is an important factor in toothbrush selection, equally integral is the ability of a given toothbrush – manual or power – to improve oral health through efficient plaque biofilm removal and reduce signs of gum disease such as inflammation and gingival bleeding. Many patients are also interested in a brush’s capacity to target cosmetic concerns, such as stain removal and whitening, and unsightly supragingival calculus.

Many factors, such as family predisposition, smoking habits, systemic disease and host defense mechanisms, determine how patients respond to the bacterial plaque existing in their oral cavities. Dental professionals cannot control or change most of these risk factors; therefore, the focus should be on the one evidence-based etiologic factor that is modifiable: the removal of bacterial plaque. It is well-documented that effective plaque removal is central to the prevention of gingivitis and periodontitis. ^14,15 Daily diligent plaque removal by the patient accompanied by professional care should focus on the elimination of dental plaque and its pathogenic products. Studies have shown that the removal of supragingival plaque affects the subgingival plaque biofilm; therefore, it reduces the clinical signs of inflammation.¹⁶

Power toothbrushes differ in their effectiveness, however, and well-controlled clinical research is essential when comparing the abilities of various brush technologies. With the revision of the American Academy of Periodontology (AAP) and European Federation of Periodontology (EFP) criteria in 2017 several unresolved issues with the previous 1999 periodontal classification were addressed by identifying the difference between presence of gingival inflammation at one or more sites and the definition of a gingivitis case. For the first time, the 2017 classification system defines clinical health and gives clear definitions of periodontal health and gingivitis.^17,18

It is agreed that bleeding on probing should be the primary parameter to set thresholds for gingivitis. As such, 10% of sites is the threshold for health/non-health. So, gingivitis studies conducted after the acceptance of the new classification system should be using the 10% threshold and addressing the odds of patients transitioning from gingival bleeding and disease to health.^18,19

Unfortunately, research has shown that many individuals do not achieve thorough plaque removal solely with use of a manual toothbrush and do not floss regularly, whether due to lack of ability or motivation.^20-22More recent research emphasizes the use of inter-dental brushes (IDB), which have been shown to be more effective plaque removal devices than string floss.^14,15 Conversely, electric toothbrushes with built in smart technology with timers can motivate patients to brush more regularly and for longer durations.^8,23,24

Also, because a skilled brushing technique is less critical as the electric brush does the work, plaque removal (both overall and proximally) can be greater with use of certain power toothbrushes and with the use of a water flosser.²⁵