Teeth Polishing

Anatomy and Physiology

Extrinsic stains vary in color according to their origin and may be green, brown, orange, or black.[7] Brown stains are usually caused by tobacco, beverages like tea, red wine, and coffee, and excessive use of chlorhexidine. Chemicals like silver, iron, manganese, and betel quid chewing more commonly cause black stains. Green stains are associated with copper and nickel metals, whereas orange stains result from chromogenic bacteria.

Indications

Polishing can only remove extrinsic stains, which can be caused by various dietary and environmental factors, such as tobacco smoking, betel quid chewing, coffee, tea, and wine drinking.[8] Intrinsic stains that occur during teeth development cannot be removed by polishing. The etiology of these stains can be developmental, drug-induced, or environmental. Furcation areas, root proximities, near restorations, and orthodontic brackets, among others, can be polished using different types of devices suited to individual needs.[9][10][7][11]

Contraindications

Tooth polishing is contraindicated in the case of intrinsic stains that may be caused by developmental defects or environmental or drug-induced factors, such as the following:

• Enamel hypoplasia
• Hypomineralization
• Dentigoneses imperfecta
• Amelogenesis imperfecta
• Dental fluorosis
• Tetracyclines stains [12]

Other contraindications include:

• Acute diseases of the gingiva and periodontal structures
• Gingival recessions
• Sensitive teeth
• Newly erupted teeth
• Xerostomia
• Allergy to paste ingredients [7]

Equipment

Abrasive agents are used for polishing to make teeth lustrous and give smooth and shiny surfaces. They are included in dentifrices and polishing pastes, with the difference that the particles are bigger in the latter.

Polishing pastes contain binders, humectants, flavoring agents, coloring agents, and preservatives to increase patient motivation. They are available in various sizes: coarse, large-sized particles, medium particles, and smooth, small fine particles.

Pastes with small particle sizes increase the smoothness and cleanliness of teeth, making them more resistant to plaque accumulation. A polishing agent should be selected so that its hardness is less than the hardness of the surface to be polished.[7]

Commonly-Used Pastes

The most frequently utilized is the flour of pumice and calcium carbonate.

• Feldspar: Used on teeth and restorations.
• Pumice: Used for polishing tooth enamel, gold foil, amalgam, and acrylic resins are siliceous materials. The disadvantage of pumice is its significant abrasive depth and average polishing capacity compared to other polishing agents.
• Calcium carbonate: Less abrasive than pumice, produces minimum scratches and a highly reflective surface.
• Perlite: A fluoride-containing abrasive agent.
• Aluminum silicate is an excellent stain remover with a great taste. It is easy to rinse off, has excellent polishing capacity, and releases fluoride.
• Xylitol-containing products: Help in saliva production and reduce dry mouth, thus helping to reduce decay, acid, and biofilm production in the mouth. They can be used in kids and are available in various sizes.
• Novamin containing products: Reduce the sensitivity and help in stain removal.
• Zirconium silicate: Used on discs and strips and prophylactic polishing pastes.[7]

Polishing Devices

• Manual: Handheld devices
• Engine-driven: Require handpieces

Preparation

Care should be taken while polishing.

• Proper technique should be used to minimize abrasion to the tooth surfaces with the appropriate force, pressure, time, and speed.
• The least abrasive polishing agent must be used and effective enough to remove the stains.
• Restorations must be polished with an agent softer than the restoration itself.[7]

Technique or Treatment

Selective Polishing

Routine tooth polishing is still the standard practice among most dental care professionals because bacteria are less likely to colonize a smooth and lustrous surface. Regular tooth polishing using the traditional method (rubber cup with prophylaxis paste) removes the enamel’s superficial layer and causes morphological changes in the tooth structure over time.[13][14] The external enamel layer takes 3 months to rebuild, and bacteria colonize the enamel surface after 30 minutes, regardless of being polished or not.[7] For all these reasons, selective polishing should only be performed on dental surfaces that remain stained after scaling.

Manual Devices

Porte Polisher

A porte polisher rubs the abrasive agent against the tooth surface with a wedge-shaped, tapered, orange-wooden point. It is noiseless, produces minimum aerosol, is portable, and is accessible to various aspects of the teeth. Hence, it can be used on malpositioned teeth and generates minimal heat. However, it has the disadvantage of being time-consuming and requiring more force.

Polishing Strips

These are for interproximal regions and line angles of teeth. Since they are very abrasive, the soft tissue in the interproximal areas must be protected. They come in various colors and sizes of abrasive agents.

Engine-Driven Devices

These are widely used and need either a straight or a contra-angled handpiece. A polishing brush or a rubber cup is attached to the handpiece used at a 2500 to 3000 rpm velocity. It is estimated that the average speed dental hygienists use is 2500 rpm.[15] The motion used for polishing in clinical practice is patting motion, and the device should be a slow-speed handpiece always rotated at the lowest rpm. The rubber cups or the polishing brushes are either autoclavable or disposable. Most tooth surfaces require 2 to 5 seconds to get polished, with the rubber cup contacting the tooth for 4.5 seconds.[7][15] The pressure needed to be applied was 20 psi since too much pressure generates heat. They are the most frequently used in clinical practice.

Air-Powder Polishers

These are generally used for supragingival plaque removal as they reach inaccessible areas where the rotary devices cannot, such as furcations, flutings, and close root proximities.[16] They use a slurry of water and sodium bicarbonate under air and water pressure, along with certain abrasive agents like aluminum trihydroxide, calcium sodium phosphosilicate, calcium carbonate, and glycine.

The air powder polisher can also be used with an ultrasonic scaler, directly with the air/water connector, or separately. It works with foot control. The nozzle of the handpiece has to be held 3 to 4 mm from the tooth as it propels the slurry of water and sodium bicarbonate on the tooth. The motion used in air powder polishers is a paintbrush motion at 60 degrees for anterior teeth, an 80-degree angle for posterior teeth, and 90 degrees on the occlusal surfaces. It should be directed at the middle thirds of the tooth in a circular motion with an air pressure of 40 to 100 psi and inlet water pressure of 20 to 60 psi.[7] Adjusting the water flow and the distance between the instrument and the tooth helps to adjust abrasive forces. They are generally safe for exogenous stain removal except for exposed dentin or cementum regions, which can be damaged because of the abrasives in the air-powder polishers.[16]

Advantages

The main advantage of air-powder polishers is their ability to efficiently remove biofilm without harming the periodontal soft tissues or hard tissue structures. This method is faster and provides more patient comfort.

1. It saves time, and hence, it can prevent patient and operator fatigue.
2. It can be used on orthodontically bracketed teeth as it does not physically damage or disturb the bands, wires, or bonding cement.
3. It reduces dentinal sensitivity by blocking the tubular opening with bicarbonate crystals.
4. It reaches inaccessible areas that cannot be reached by rotary devices.[17]

Disadvantages

Since the slurry uses sodium bicarbonate, it should be used cautiously in patients with restricted sodium diets. In such cases, non-sodium prophy powder, which contains aluminum trihydroxide, can be used.

1. It should be carefully used in patients with respiratory, renal, or metabolic disease, diuretics, long-term steroid therapy, those having titanium implants, or with children and in patients with infectious diseases.
2. Infection control is a problem with these devices since they produce aerosols. Hence, pretreatment washes are recommended.[17]
3. There is a risk of subcutaneous emphysema intraorally. It is important to follow the manufacturer's instructions to avoid such complications.[7]

Air polishers are generally used on supragingival surfaces. Still, glycine powder air polishers are used for removing sub-gingival biofilm, resulting in less erosion of the soft tissues and an 80% reduction in abrasion of the root surface as compared to hand instrumentation or sodium bicarbonate air polishing.[7]

Vector System

These use a polishing fluid, which causes minimum damage to the cementum surface. The polishing fluid contains hydroxyapatite or an abrasive fluid containing silicon carbide with a resonating device that deflects the forces directed toward the tooth and hence protects the tooth. The plaque is removed by fluid dynamics and gives effective control of inflammation.[7]

Complications

When polishing pastes with coarse or medium-sized particles are used, they may cause abrasion and damage to the tooth surface by scratching the enamel. A less polished appearance can be seen, increasing bacterial plaque retention.[7] Manual devices are time-consuming, and there is no control over the force applied, and they require more patient compliance. With engine-driven polishers, there is higher aerosol production, heat generation, and damage to the soft tissue if not properly attended.

Clinical Significance

Extrinsic stains are widespread in dental practice because they can be caused by tobacco smoking or simply drinking too much coffee or tea. The tooth polishing devices are selected according to each case, and treatment plans are selectively designed, taking into account the patient's needs and with concern about minimal damage to the teeth and periodontal structures.

Extrinsic stains are 1 of the factors that influence tooth color assessment. Performing professional dental prophylaxis before composite or ceramic color selection in anterior teeth restorations could increase treatment predictability.[18]

Enhancing Healthcare Team Outcomes

When the nature of dental stains has been identified as exogenous, selective tooth polishing is the initial and most straightforward alternative to remove them after scaling and oral debridement is complete.[7] Dental professionals must know the alternatives when selecting a polishing paste and devices and adjust them to each clinical case.