Oral Hygiene and Dental Plaque
Dental prophylaxis remains the standard of care for plaque removal. Gingivitis, the inflammatory response to pathogenic plaque, is typically minimized or resolved a few days after prophylaxis. Follow-on at-home care plays a critical role in post-prophylaxis oral hygiene and health.
Clinical research has shown the extent of plaque formation varies widely from person to person, ranging from 4-37% of tooth surfaces covered with plaque before brushing.1 Routine morning tooth brushing with a regular manual brush and dentifrice removed only approximately 50% of overnight plaque (Figure 1). Despite these variations in plaque formation, incomplete plaque removal was ubiquitous, and every participant had at least 2% of tooth surfaces covered with residual plaque after brushing.
The re-accumulation of dental plaque after prophylaxis contributes to some of the most common oral diseases and conditions. From a disease perspective, bacterial plaque plays an etiological role in the prevalence and severity of dental caries and periodontal disease. Plaque accumulation is further associated with calculus formation, some malodors, and aspects of extrinsic tooth staining. Over the longer term, oral bacteria may play a direct or indirect role in recession and attendant dentinal hypersensitivity, wound healing, tooth loss and other pertinent clinical outcomes.
Daily Oral Home Care Protocol
Daily oral hygiene is usually multi-factorial involving a variety of oral care products (brushes, pastes, rinses, picks, flosses…) and multiple techniques (scrubbing, gliding, swishing, irrigating, scraping…) learned over time. All or some of these may change regularly based on a marketing campaign, personal perception or other factors. A common outcome of at-home hygiene practices is plaque re-accumulation and rapid reoccurrence of gingivitis after prophylaxis – the so-called “cycle of gingivitis” – that is often evident by the next recall visit.
How do we “break the cycle”?
We developed a simple protocol for oral home care designed to help break the cycle, and then tested that protocol in a series of clinical studies. The protocol is grounded in proven technical performance with broad application across patient types, and acceptability for use in both the office and home. Our desired characteristics included:
- Thorough removal of existing plaque and inhibition of plaque regrowth
- Relevance to a wide range of patient types without major contraindications
- Easy implementation in-office, use at-home, and monitoring at recall
We selected a combination approach using mechanical and chemical plaque removal from different sources with different techniques. Our simple, three-step protocol for plaque control is based on the use of:
1) advanced power brush technology with at-home feedback
2) multi-benefit therapeutic dentifrice
3) therapeutic rinse
The first component is the rotation-oscillation power brushing technology that systematic review shows removes significantly more plaque than conventional manual brushing.2 We use the power brush with integrated telemetry and a wireless display (Oral-B® Professional SmartCare Series 5000 with SmartGuide), because this technology has been shown to provide immediate at-home patient feedback on brushing technique location and intensity (Figure 2).3 Of interest, this technique can help slow down the brushing experience, which in turn, can have indirect benefits with respect to dentifrice contact time.
The second component is a stannous fluoride dentifrice technology that exhibits broad spectrum antimicrobial activity, in part, by direct inhibition of bacterial metabolism and growth.4 The clinical protocol focuses on plaque control, but the selected multi-benefit dentifrice (Crest® Pro-Health) also has effects on gingivitis, caries, and sensitivity, all of which are attributable to a stannous fluoride mechanism, along with various cosmetic benefits. This extends the range of benefits to meet diverse patient needs.
The third component involves post-brushing use of an antiplaque rinse. Therapeutic rinses with antiplaque and antigingivitis properties have long been recognized to contribute to the prevention and treatment of periodontal diseases. The alcohol-free cetylpyridinium chloride rinse (Crest Pro-Health Multi-Protection) was selected because the absence of alcohol helps promote compliance, while the substantive cetylpyridinium chloride active binds to plaque, contributing to both “on contact” and sustained antiplaque effects.5
Evidence of Effectiveness
Clinical trials are recognized to represent the highest evidence of safety and effectiveness. For plaque, prominent clinical methods have been used for several decades to assess erythrocin-disclosed plaque. More recently, instrumental methods have been developed using digital photography and image analysis to precisely locate and measure dental plaque.6 Individuals rinse with a fluorescent dye that allows plaque to appear lime green with special lighting. Unlike red dye, the fluorescent plaque can be readily distinguished from other oral tissues (that are not lime green), and image analysis can easily quantify plaque surface area (% coverage).
Importantly, the plaque imaging method can be used to assess outcomes in typical patients in a blinded and unbiased fashion, helping assure the quality and relevance of outcomes. The method has been applied in clinical trials to measure plaque before and after combination treatment, where a key endpoint is overnight (morning unbrushed) plaque area. Clinical outcomes have been impressive with power brush and therapeutic paste plus rinse combinations yielding appreciable reductions in overnight plaque coverage after a few days of at-home use (Figure 3).
Research findings have demonstrated that use of oral home care combinations (power+paste+rinse) for a few weeks yields similar or lower overnight plaque coverage before brushing compared to regular oral hygiene after brushing. Other research has shown these combinations limit daytime plaque growth. Plausibly, the very low plaque accumulation is the product of brushing effectiveness (mechanical plaque removal) plus sustained antibacterial activity including inhibition of plaque regrowth (chemotherapeutic effectiveness). Thorough and repetitive mechanical disruption may help contribute to a thin plaque, making residual plaque susceptible to antimicrobials in the paste and rinse. Of course, causality cannot be determined from multi-variable studies, and further research would be needed to identify the contributions of any individual component to the overall system results.
Clinical Application and Patient Selection
The combination was selected, in part, for ease of implementation in-office and use at-home across a broad range of patient types. Clinical trials outcomes were achieved without extensive or highly specialized training at chairside. In fact, products were supplied over-packaged in simple test kits (for blinding purposes), training lasted about two minutes, and subsequent use in clinical trials was at-home and unsupervised.
With respect to patient selection, the clinical research had few entrance criteria to allow the broadest possible implications. (Sometimes, clinical trials are conducted in highly selective populations that may or may not represent the average patient, so inference of such findings may be unknown.) We chose the rotation-oscillation brush with telemetry for the oral home care protocol because the telemetry provides feedback that takes training from the dental practice to the home. The paste and rinse were selected not just because of effectiveness, but also because of the esthetics, acceptabili
ty and compliance, and use of an alcohol-free rinse allowed even broader application across patient types.
Research demonstrates the merits of the combination approach for plaque control broadly in practice, even with complex cases. Orthodontia is often seen as a “torture test”, with excessive plaque accumulation contributing to white spots, bleeding, and the like, compromising treatment outcomes. This case from a clinical trial (courtesy of Dr. M. Klukowska) illustrates the extent of plaque control that can be achieved in two weeks with the oral home care protocol (Figure 4). Other research has tested use with esthetic dentistry, implant/restorative cases, and others, where plaque accumulation and bleeding may affect clinical response.
What about flossing?
Flossing can play an important role, as evidenced by results from one large survey where daily flossing was associated with a 50%+ reduction in bleeding.7 In clinical research, we have added dental floss to daily oral hygiene with impressive outcomes, so flossing can be freely introduced initially, or later for those patients where there is evidence of persistent plaque accumulation or evident bleeding at recall. Oral health outcomes with daily home care are the result of technology (such as advanced brushes) and behavior (such as reluctant flossing), so protocols may be varied based on individual needs or conditions. Treatment planning, in-office training, and recall monitoring will certainly play an important role in expanding the use of combination regimens for plaque control.
Other than very young children (who rarely have plaque-associated gingivitis), contraindications are few, labeled instructions for use apply, and there are no serious adverse events with normal care. The actives occasionally contribute to temporary taste effects, or minor tooth staining in hard-to-clean areas. Monitoring remains a key element in any successful oral home care protocol, so that dental professionals can evaluate response and treat accordingly. Bleeding may represent a useful endpoint for clinical monitoring, since this provides a longer term perspective on home care.
Summary
Ineffective oral hygiene contributes to ubiquitous dental plaque, and plaque-associated gingivitis is one of the most common oral diseases. Clinical research demonstrates the effectiveness of specific combinations involving advanced brushes along with therapeutic paste and rinse to achieve mechanical and chemical plaque control across a broad range of patient types. To date, there has been relatively little clinical research on product combinations, so care should be taken in extending clinical findings from this research to other untested combinations. OH
Dr. Gerlach is Adjunct Professor, Tufts University School of Dentistry and Research Fellow, The Procter & Gamble Company, Cincinnati, OH USA.
Oral Health welcomes this original article.
References
1. Gerlach RW, Barker ML, Rubush ML, Walanski AA, Karpinia K, Magnusson I. Use of digital plaque image analysis for monitoring brushing effectiveness. J Dent Res J Dent Res 2010;89 (Spec Iss B): Abstract #1721.
2. Robinson PG, Deacon SA, Deery C, Heanue M, Walmsley AD, Worthington HV, Glenny AM, Shaw WC. Manual versus powered toothbrushing for oral health. Cochrane Database Syst Rev 2005;18 (2):CD002281.
3. Janusz K, Nelson B, Bartizek RD, Walters PA, Biesbrock AR. Impact of a novel power toothbrush with SmartGuide technology on brushing pressure and thoroughness. J Contemp Dent Pract 2008;9:1-8.
4. Ramji N, Baig A, He T, Lawless MA, Saletta L, Suszcynsky-Meister E, Coggan J. Sustaines antibacterial actions of a new stabilized stannous fluoride dentifrice containing sodium hexametaphosphate. Compend Contin Educ Dent 2005;26(Suppl 1):19-28.
5. Kornman KS. The role of supragingival plaque in the prevention and treatment of periodontal diseases: A review of current concepts. J Periodont Res 1986;16:5-22.
6. Sagel PA, Lapujade PG, Miller JM, Sunberg RJ. Objective quantification of plaque using digital image analysis. Monogr Oral Sci 2000;17:130-43.
7. Gerlach RW, Bartizek RD, Biesbrock AR, Dunavent JM, Gibb RD, McClanahan SF. Oral hygiene, perceived health and gingivitis occurrence, distribution and severity. J Dent Res 2006;85 (Spec Iss A): Abstract #1113.
