Dental biofilm, commonly known as plaque, is a complex, sticky community of microorganisms that constantly forms on the surface of teeth. This matrix-enclosed bacterial layer is a precursor to tooth decay and gum disease, making its consistent removal the foundation of oral health. Managing this accumulation requires a combination of daily habits and periodic professional intervention. This article outlines the specific methods needed for the effective removal of this persistent film, both at home and in the dental office.
Understanding How Biofilm Forms
The formation of dental biofilm is a dynamic, multi-stage process beginning immediately after a tooth surface is cleaned. Within minutes, salivary proteins and glycoproteins adhere to the enamel, creating a thin coating called the acquired pellicle. This non-bacterial film acts as the initial anchor point for pioneer bacterial species, primarily Streptococcus species, which begin to colonize the surface.
As these initial colonizers multiply, they secrete an extracellular polymeric substance (EPS) matrix, a sticky scaffold composed largely of polysaccharides, proteins, and nucleic acids. This matrix encases the growing microbial community, forming a protected, three-dimensional structure highly resistant to rinsing or the body’s natural defenses. The mature, soft biofilm, or plaque, can lead to gingivitis. If left undisturbed, the microbial balance shifts toward species associated with periodontitis.
Over time, calcium and phosphate minerals from saliva incorporate into the biofilm matrix, causing it to harden into dental calculus, also known as tartar. Calculus is a mineralized form of plaque that requires professional removal.
Daily Mechanical Removal Techniques
Physical disruption is the most effective way to remove the soft, developing biofilm before it mineralizes into calculus. The primary method is the Bass or Modified Bass brushing technique, which specifically targets the sulcus, the small pocket between the tooth and gum line where plaque accumulates most rapidly. To perform this, a soft-bristled toothbrush is angled at 45 degrees toward the gum line, with the bristles gently inserted into the sulcus.
The brush is then moved with short, gentle, horizontal, or vibratory strokes across one or two teeth at a time, dislodging the biofilm from the critical margin. This action must be performed for a minimum of two minutes, twice daily, to ensure every surface is treated and bacterial colonies are broken up. Brushing alone, however, cleans only the outer, inner, and chewing surfaces, leaving approximately 40% of the tooth surface untouched within the interproximal spaces.
Cleaning these missed surfaces requires the use of interdental tools, as these areas are breeding grounds for plaque unreachable by a toothbrush. Dental floss, interdental brushes, or water flossers must be used at least once a day to scrape the biofilm from between the teeth and just below the gum line. Interdental brushes are highly effective for accessing and disrupting the biofilm in the triangular space between teeth. The goal of all home care is mechanical removal of the sticky, organized bacterial community.
Chemical Agents and Supportive Products
Chemical agents serve as a supportive measure to enhance mechanical removal by disrupting the biofilm structure or inhibiting bacterial growth. These products are never a substitute for brushing and flossing, but they provide an antimicrobial advantage. Specialized toothpastes often incorporate agents like stannous fluoride, which provides anti-cavity benefits and has mild antimicrobial properties that interfere with bacterial metabolism and adhesion.
Mouth rinses contain active ingredients that target bacterial cell walls and interfere with the formation of the extracellular matrix. Cetylpyridinium chloride (CPC) is a common compound in over-the-counter rinses that binds to oral tissues and reduces plaque buildup by rupturing the bacterial membrane.
Chlorhexidine digluconate is a potent broad-spectrum antimicrobial agent considered the gold standard for chemical plaque control. It works by binding strongly to oral tissues and slowly releasing its effect over several hours. Chlorhexidine is available only by prescription due to its high efficacy and potential for side effects like temporary staining, and its use is reserved for short-term management of gingivitis or after surgical procedures.
While chemical aids can significantly reduce the bacterial load and inhibit plaque regrowth, their effectiveness relies on direct contact with the biofilm. Mechanical scrubbing remains necessary because the mature biofilm matrix provides a protective shield that reduces the penetration of these chemical agents.
Professional Dental Cleaning Procedures
When daily mechanical efforts are insufficient, the soft biofilm mineralizes into calculus, requiring professional intervention for removal. Dental professionals use scaling to remove this hardened deposit, as it adheres strongly to the tooth surface and is impossible to remove with a toothbrush or floss. Scaling involves the use of specialized instruments, either manual periodontal curettes or ultrasonic scalers.
Ultrasonic scalers utilize high-frequency vibrations combined with a water spray to fracture the calculus deposits from the enamel and root surfaces. Scaling is performed both above the gum line (supragingival) and below the gum line (subgingival), where calculus causes inflammation and pockets to form. Following calculus removal, root planing is often performed, which involves smoothing the surface of the tooth root.
Root planing is necessary because the root surface can become rough and contaminated with bacterial toxins once the gum tissue pulls away. Smoothing the root surface removes these endotoxins and discourages future plaque accumulation. This creates an environment where the gum tissue can potentially reattach to the tooth. Regular professional cleanings are the only way to eliminate calcified biofilm that home care cannot reach, preventing the progression of periodontal disease.