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Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
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Personal hygiene care consists of proper brushing and flossing daily. The purpose of oral hygiene is to minimize any etiologic agents of disease in the mouth. The primary focus of brushing and flossing is to remove and prevent the formation of plaque or dental biofilm. Plaque consists mostly of bacteria. As the amount of bacterial plaque increases, the tooth is more vulnerable to dental caries when carbohydrates in the food are left on teeth after every meal or snack. A toothbrush can be used to remove plaque on accessible surfaces, but not between teeth or inside pits and fissures on chewing surfaces. When used correctly, dental floss removes plaque from areas that could otherwise develop proximal caries but only if the depth of sulcus has not been compromised. Other adjunct oral hygiene aids include interdental brushes, water picks, and mouthwashes.
However oral hygiene is probably more effective at preventing gum disease (periodontal disease) than tooth decay. Food is forced inside pits and fissures under chewing pressure, leading to carbohydrate-fueled acid demineralisation where the brush, fluoride toothpaste, and saliva have no access to remove trapped food, neutralise acid, or remineralise demineralised tooth like on other more accessible tooth surfaces. (Occlusal caries accounts for between 80 and 90% of caries in children (Weintraub, 2001).) Higher concentrations of fluoride (>1,000 ppm) in toothpaste also helps prevents tooth decay, with the effect increasing with concentration. Chewing fibre like celery after eating forces saliva inside trapped food to dilute any carbohydrate like sugar, neutralise acid and remineralise demineralised tooth. The teeth at highest risk for carious lesions are the permanent first and second molars due to length of time in oral cavity and presence of complex surface anatomy.
Professional hygiene care consists of regular dental examinations and professional prophylaxis (cleaning). Sometimes, complete plaque removal is difficult, and a dentist or dental hygienist may be needed. Along with oral hygiene, radiographs may be taken at dental visits to detect possible dental caries development in high-risk areas of the mouth (e.g. "bitewing" X-rays which visualize the crowns of the back teeth).
Fluoride is a natural mineral that naturally occurs throughout the world – it is also the active ingredient of many toothpastes specifically for its remineralizing effects on enamel, often repairing the tooth surface and reducing the risk of caries.
The use of fluoridated toothpaste is highly recommended by dental professionals; whereby studies suggest that the correct daily use of fluoride on the dentition of children has a high caries-preventive effect and therefore prevents has potential to prevent ECC. However, it is important to use fluoridated toothpastes correctly; children below the age of two do not usually require toothpaste unless they are already at a high risk of ECC as diagnosed by a dental professional, and therefore it is it is recommended to use a small sized ‘smear’ of toothpaste to incorporate fluoride, with caution removing the toothpaste from within the mouth and not allowing the child to swallow the substances.
On eruption of the first primary tooth in a child, tooth brushing and cleaning should be performed by an adult. This is important as the plaque that attaches to the surface of the tooth has bacteria that have the ability to cause caries (decay) on the tooth surface.
It is recommended to brush children’s teeth using a soft bristled, age and size appropriate toothbrush and age appropriate toothpaste twice daily, however children below the age of two usually don’t require toothpaste. These researches also suggest that it is suitable to brush children’s teeth until they reach the approximate age of 6; where they will begin to learn adequate dexterity and cognition needed for adequate brushing by themselves. It is encouraged to watch children brushing their teeth until they are competently able to brush appropriately alone.
The use of dental sealants is a means of prevention. A sealant is a thin plastic-like coating applied to the chewing surfaces of the molars to prevent food from being trapped inside pits and fissures. This deprives resident plaque bacteria of carbohydrate, preventing the formation of pit and fissure caries. Sealants are usually applied on the teeth of children, as soon as the teeth erupt but adults are receiving them if not previously performed. Sealants can wear out and fail to prevent access of food and plaque bacteria inside pits and fissures and need to be replaced so they must be checked regularly by dental professionals.
Calcium, as found in food such as milk and green vegetables, is often recommended to protect against dental caries. Fluoride helps prevent decay of a tooth by binding to the hydroxyapatite crystals in enamel. Streptococcus mutans is the leading cause of tooth decay. Low concentration fluoride ions act as bacteriostatic therapeutic agent and high concentration fluoride ions are bactericidal. The incorporated fluorine makes enamel more resistant to demineralization and, thus, resistant to decay. Topical fluoride is more highly recommended than systemic intake such as by tablets or drops to protect the surface of the teeth. This may include a fluoride toothpaste or mouthwash or varnish. Standard fluoride toothpaste (1,000–1,500 ppm) is more effective than low fluoride toothpaste (< 600ppm) to prevent dental caries. After brushing with fluoride toothpaste, rinsing should be avoided and the excess spat out. Many dental professionals include application of topical fluoride solutions as part of routine visits and recommend the use of xylitol and amorphous calcium phosphate products. Silver diamine fluoride may work better than fluoride varnish to prevent cavities. Water fluoridation also lowers the risk of tooth decay.
An oral health assessment carried out before a child reaches the age of one may help with management of caries. The oral health assessment should include checking the child’s history, a clinical examination, checking the risk of caries in the child including the state of their occlusion and assessing how well equipped the child’s parent or carer is to help the child prevent caries. In order to further increase a child’s cooperation in caries management, good communication by the dentist and the rest of the staff of a dental practice should be used. This communication can be improved by calling the child by their name, using eye contact and including them in any conversation about their treatment.
Vaccines are also under development.
Dental fluorosis may or may not be of cosmetic concern. In some cases, there may be varying degrees of negative psychosocial effects. The treatment options are:
- Tooth bleaching
- Micro-abrasion
- Composite fillings
- Veneers
- Crowns
Generally, more conservative options such as bleaching are sufficient for mild cases.
Many impacted wisdom teeth are extracted prior to the age of 25, when full eruption can be reasonably expected and before symptoms or disease have begun. This has led to a treatment controversy generally referred to as the extraction of asymptomatic, disease-free wisdom teeth.
In 2000, the first National Institute of Clinical Excellence (NICE) of the United Kingdom set guidelines to limit the removal of asymptomatic disease-free third molars citing the number of pathology free impacted teeth being removed and the potential cost savings to the public purse. Advocates of the policy point out that the impacted wisdom teeth can be monitored and avoidance of surgery also means avoidance of the recovery, risks, complications and costs associated with it. Following implementation of the NICE guidelines the UK saw a decrease in the number of impacted third molar operations between 2000 and 2006 and a rise in the average age at extraction from 25 to 31 years. American Public Health Association has adopted a similar policy against removal of third molars before any problems have occurred.
Those who argue against a blanket moratorium on the extraction of asymptomatic, disease-free wisdom teeth point out that wisdom teeth commonly develop periodontal disease or cavities which may eventually damage the second molars and that there are costs associated with monitoring wisdom teeth. They also point to the fact that there is an increase in the rate of post-operative periodontal disease on the second molar, difficulty of surgery and post-operative recovery time with age. The UK has also seen an increase in the rate of dental caries on the lower second molars increasing from 4–5% prior to the NICE guideline to 19% after its adoption.
Although most studies arrive at the conclusion of negative long-term outcomes e.g. increased pocketing & attachment loss after surgery, it is clear that early removal (before 25 years old), good post-operative hygiene & plaque control, and lack of pre-existing periodontal pathology before surgery are the most crucial factors that minimise the probability of adverse post-surgical outcomes.
The Cochrane review of surgical removal versus retention of asymptomatic disease-free impacted wisdom teeth suggests that the presence of asymptomatic impacted wisdom teeth may be associated with increased risk of periodontal disease affecting adjacent 2nd molar (measured by distal probing depth > 4 mm on that tooth) in the long term, however it is of very low quality evidence and high risk of bias. Another study which was at high risk of bias, found no evidence to suggest that removal of asymptomatic disease-free impacted wisdom teeth has an effect on crowding in the dental arch. There is also insufficient evidence to highlight a difference in risk of decay with or without impacted wisdom tooth.
One trial in adolescents who had orthodontic treatment comparing the removal of impacted mandibular wisdom teeth with retention was identified. It only examined the effect on late lower incisor crowding and was rated 'highly biased' by the authors. The authors concluded that there is not enough evidence to support either the routine removal or retention of asymptomatic impacted wisdom teeth. Another randomised controlled trial done in the UK has suggested that it is not reasonable to remove asymptomatic disease-free impacted wisdom tooth merely to prevent incisor crowding as there is not strong enough evidence to show this association.
Due to the lack of sufficient evidence to determine whether such teeth should be removed or not, the patient's preference and values should be taken into account with clinical expertise exercised and careful consideration of risks & benefits to determine treatment. If it is decided to retain asymptomatic disease-free impacted wisdom teeth, clinical assessment at regular intervals is advisable to prevent undesirable outcomes (pericoronitis, root resorption, cyst formation, tumour formation, inflammation/infection).
Fluorosis is extremely common, with 41% of adolescents having definite fluorosis, and another 20% "questionably" having fluorosis according to the Centers for Disease Control.
The U.S. Centers for Disease Control found a 9 percentage point increase in the prevalence of confirmed dental fluorosis in a 1999-2002 study of American children and adolescents than was found in a similar survey from 1986-1987 (from 22.8% in 1986-1987 to 32% in 1999-2002). In addition, the survey provides further evidence that African Americans suffer from higher rates of fluorosis than Caucasian Americans.
The condition is more prevalent in rural areas where drinking water is derived from shallow wells or hand pumps. It is also more likely to occur in areas where the drinking water has a fluoride content greater than 1 ppm (part per million).
If the water supply is fluoridated at the level of 1 ppm, one must consume one litre of water in order to take in 1 mg of fluoride. It is thus improbable a person will receive more than the tolerable upper limit from consuming optimally fluoridated water alone.
Fluoride consumption can exceed the tolerable upper limit when someone drinks a lot of fluoride-containing water in combination with other fluoride sources, such as swallowing fluoridated toothpaste, consuming food with a high fluoride content, or consuming fluoride supplements. The use of fluoride supplements as a prevention for tooth decay is rare in areas with water fluoridation, but was recommended by many dentists in the UK until the early 1990s.
Dental fluorosis can be prevented by lowering the amount of fluoride intake to below the tolerable upper limit.
In November 2006 the American Dental Association published information stating that water fluoridation is safe, effective and healthy; that enamel fluorosis, usually mild and difficult for anyone except a dental health care professional to see, can result from ingesting more than optimal amounts of fluoride in early childhood; that it is safe to use fluoridated water to mix infant formula; and that the probability of babies developing fluorosis can be reduced by using ready-to-feed infant formula or using water that is either free of fluoride or low in fluoride to prepare powdered or liquid concentrate formula. They go on to say that the way to get the benefits of fluoride but minimize the risk of fluorosis for a child is to get the right amount of fluoride, not too much and not too little. "Your dentist, pediatrician or family physician can help you determine how to optimize your child’s fluoride intake."
Prevention is of prior importance at an early developmental age as the defective tooth is more likely to have caries and post-eruptive breakdown due to its increased porosity. Appropriate dietary advice and toothpaste with a fluoride level of at least 1,000 ppm F should be recommended. For treating spontaneous hypersensitivity professional applications of fluoride varnish (e.g. Duraphat 22,600ppm F) or 0.4% stannous fluoride gel may be helpful.
Casein Phosphopepetide-Amorphus Calcium Phosphate (CPP-ACP) provides a supersaturated environment of calcium and phosphate on the enamel surface to enhance remineralisation in the form of toothpaste or sugar free chewing gum. Its clinical effectiveness is still debatable but may benefit those patients who complain of mild pain to external stimuli.
Wisdom teeth removal (extraction) is the most common treatment for impacted wisdom teeth. In the US, 10 million wisdom teeth are removed annually. The general agreement for wisdom tooth removal is the presence of disease or symptoms related to that tooth.
The procedure, depending on the depth of the impaction and angle of the tooth, is to create an incision in the mucosa of the mouth, remove bone of the mandible or maxilla adjacent the tooth, section the tooth and extract it in pieces. This can be completed under local anaesthetic, sedation or general anaesthetic.
Preventive and management strategies include the following:
- Avoid sweet and acid foods. Even low sugar contained in fruit is bad for the teeth since it is the sugar/acid exposure time which erodes the teeth, not the amount of sugar.
- Modifying the pH of the food or beverage contributing to the problem, or changing lifestyle to avoid the food or beverage.
- Rinsing immediately after drinking or eating.
- Drinking through a straw
- Avoid abrasive forces. Use a soft bristled toothbrush and brush gently. Avoid brushing immediately after consuming acidic food and drink as teeth will be softened. Leave at least half an hour of time in between. Rinsing with water is better than brushing after consuming acidic foods and drinks.
- Using a remineralizing agent, such as sodium fluoride solution in the form of a fluoride mouthrinse, tablet, or lozenge, immediately before brushing teeth.
- Applying fluoride gels or varnishes to the teeth.
- Drinking milk or using other dairy products.
- Dentine bonding agents applied to areas of exposed dentin
- Use a neutralizing agent such as antacid tablets only as a last-resort. They have negative long-run effects.
- Treating the underlying medical disorder or disease.
In order for successful treatment of abrasion to occur, the aetiology first needs to be identified. The most accurate way of doing so is completing a thorough medical, dental, social and diet history. All aspects needs to be investigated as in many cases the cause of abrasion can be multi-factorial. Once a definitive diagnosis is completed the appropriate treatment can commence.
Treatment for abrasion can present in varying difficulties depending on the current degree or progress caused by the abrasion. Abrasion often presents in conjunction with other dental conditions such as attrition, decay and erosion however the below treatment is for abrasion alone. Successful treatment focuses on the prevention and progression on the condition and modifies the current habit/s instigating the condition.
At-home treatments include desensitizing toothpastes or dentifrices, potassium salts, mouthwashes and chewing gums.
A variety of toothpastes are marketed for dentin hypersensitivity, including compounds such as strontium chloride, strontium acetate, arginine, calcium carbonate, hydroxyapatite and calcium sodium phosphosilicate. Desensitizing chewing gums and mouthwashes are also marketed.
Potassium-containing toothpastes are common; however, the mechanism by which they may reduce hypersensitivity is unclear. Animal research has demonstrated that potassium ions placed in deep dentin cavities cause nerve depolarization and prevent re-polarization. It is not known if this effect would occur with the twice-daily, transient and small increase in potassium ions in saliva that brushing with potassium-containing toothpaste creates. In individuals with dentin hypersensitivity associated with exposed root surfaces, brushing twice daily with toothpaste containing 5% potassium nitrate for six to eight weeks reduces reported sensitivity to tactile, thermal and air blast stimuli. However, meta analysis reported that these individuals' subjective report of sensitivity did not significantly change after six to eight weeks of using the potassium nitrate toothpaste.
Desensitizing toothpastes containing potassium nitrate have been used since the 1980s while toothpastes with potassium chloride or potassium citrate have been available since at least 2000. It is believed that potassium ions diffuse along the dentinal tubules to inactivate intradental nerves. However, , this has not been confirmed in intact human teeth and the desensitizing mechanism of potassium-containing toothpastes remains uncertain. Since 2000, several trials have shown that potassium-containing toothpastes can be effective in reducing dentin hypersensitivity, although rinsing the mouth after brushing may reduce their efficacy.
Studies have found that mouthwashes containing potassium salts and fluorides can reduce dentine hypersensitivity, although rarely to any significant degree. , no controlled study of the effects of chewing gum containing potassium chloride has been made, although it has been reported as significantly reducing dentine hypersensitivity.
Nano-hydroxyapatite (nano-HAp) is considered one of the most biocompatible and bioactive materials, and has gained wide acceptance in dentistry in recent years. An increasing number of reports have shown that nano-hydroxyapatite shares characteristics with the natural building blocks of enamel having the potential, due to its particle size, to occlude exposed dentinal tubules helping to reduce hypersensitivity and enhancing teeth remineralization.
For this reason, the number of toothpastes and mouthwashes that already incorporate nano-hydroxyapatite as a desensitizing agent is increasing.
The frequency of first permanent molar treatment for children with MIH is nearly 10 times greater compared to children without MIH. The available treatment modalities for MIH is extensive but the decision on which treatment should be used is complex and multi-factorial. Factors may include: condition severity, the patient’s dental age, the child/parent’s social background and expectations. There are treatment modalities available to manage children affected by MIH; however, the evidence supporting these modalities are still weak.
The aetiology of dental abrasion can be due to a single stimuli or, as in most cases, multi-factorial. The most common cause of dental abrasion, is the combination of mechanical and chemical wear.
Tooth brushing is the most common cause of dental abrasion, which is found to develop along the gingival margin, due to vigorous brushing in this area. The type of toothbrush, the technique used and the force applied when brushing can influence the occurrence and severity of resulting abrasion. Further, brushing for extended periods of time (exceeding 2-3 min) in some cases, when combined with medium/hard bristled toothbrushes can cause abrasive lesions.
Different toothbrush types are more inclined to cause abrasion, such as those with medium or hard bristles. The bristles combined with forceful brushing techniques applied can roughen the tooth surface and cause abrasion as well as aggravating the gums. Repetitive irritation to the gingival margin can eventually cause recession of the gums. When the gums recede, the root surface is exposed which is more susceptible to abrasion.
Comparatively, electric toothbrushes have less abrasive tendencies.
Types of toothpastes can also damage enamel and dentine due to the abrasive properties. Specific ingredients are used in toothpaste to target removal of the bio-film and extrinsic staining however in some cases can contribute to the pastes being abrasive.
Whitening toothpastes are found to be one of the most abrasive types of toothpastes, according to the RDA Scale, detailed below. In-home and clinical whitening have been proven to increase the likelihood of an individual experiencing dental abrasion. It is believed that dental abrasion due to the whitening process is caused by a combination of both mechanical and chemical irritants, for example, using whitening toothpaste and at home bleaching kits together. However, if an individual is regimented in their after-whitening care then they can avoid loss of dentine minerals and in turn abrasion can be avoided. (that contribute to developing abrasion).
Another factor that can contribute to abrasion is alteration of pH levels in the saliva. This can be sugary/ acidic foods and liquids. The reasoning behind this is that an increase in acidity of saliva can induce demineralization and therefore compromising the tooth structure to abrasive factors such as tooth brushing or normal wear from mastication. When the tooth structure is compromised, this is where the mineral content of the saliva can create shallow depressions in the enamel and thus, when brushed can cause irreparable damage on tooth surface. The dental abrasion process can be further stimulated and accelerated through the effects of dental Acid erosion.
Disclosing tablets are similar to that of disclosing gels, except that they are placed in the mouth and chewed on for approximately one minute. The remaining tablet or saliva is then spit out. Disclosing gels will show the presence of the plaque, but will often not show the level of maturity of the plaque. Disclosing tablets are often prescribed or given to patients with orthodontic appliances for use before and after tooth brushing to ensure optimal cleaning. These are also helpful educational tools for young children or patients that are struggling to remove dental plaque in certain areas. Disclosing gels and tablets are useful for individuals of all ages in ensuring efficient dental plaque removal.
When a diagnosis of bruxism has been confirmed, it is recommended that the patient buy a full-coverage acrylic occlusal splint, such as a Michigan Splint or Tanner appliance, to prevent further bruxism. Patients must be monitored closely, with clinical photographs 6–12 monthly to evaluate if the tooth surface loss is being prevented.
Gingival recession and cervical tooth wear can be avoided by healthy dietary and oral hygiene practices. By using a non-traumatic toothbrushing technique (i.e. a recommended technique such as the modified Bass technique rather than indiscriminately brushing the teeth and gums in a rough scrubbing motion) will help prevent receding gums and tooth wear around the cervical margin of teeth. Non-abrasive toothpaste should be used, and brushing should be carried out no more than twice per day for two minutes on each occasion. Excessive use of acidic conditions around the teeth should be avoided by limiting consumption of acidic foods and drinks, and seeking medical treatment for any cause of regurgitation/reflux of stomach acid. Importantly, the teeth should not be brushed immediately after acidic foods or drinks. A non-abrasive diet will also help to prevent tooth wear. Flossing each day also helps to prevent gum recession caused by gum disease.
Teeth whitening products can make your teeth sensitive. However, the increased sensitivity is temporary and will go away within a few days. If teeth sensitivity is experienced after using a teeth whitening product, taking a break may help.
Dental caries is an infectious disease caused primarily by "Streptococcus mutans", characterized by acid demineralization of the enamel, which can progress to further breakdown of the more organic, inner dental tissue (dentin). Everybody is susceptible to caries but the probability of development depends on the patient’s individual disease indicators, risk factors and preventive factors. Factors that are considered high-risk for developing carious lesions on the teeth include:
- Low fluoride exposure
- Time, length, and frequency of sugar consumption
- Quality of tooth cleaning
- Fluctuations in salivary flow rates and composition
- Behavior of the individual
- Socioeconomic status of the individual
- Quality and composition of biofilms
Organic acids released from dental plaque lead to demineralization of the adjacent tooth surface, and consequently to dental caries. Saliva is also unable to penetrate the build-up of plaque and thus cannot act to neutralize the acid produced by the bacteria and remineralize the tooth surface.
Acidic drinks and foods lower the pH level of the mouth so consuming them causes the teeth to demineralise. Drinks low in pH levels that cause dental erosion include fruit juices, sports drinks, wine, beer and carbonated drinks. Orange and apple juices are common culprits among fruit juices. Carbonated drinks such as colas, lemonades are also very acidic, as are fruit-flavoured drinks and dilutables. Frequency rather than total intake of acidic juices is seen as the greater factor in dental erosion; infants using feeding bottles containing fruit juices (especially when used as a comforter) are therefore at greater risk of acid erosion.
Saliva acts as a buffer, regulating the pH when acidic drinks are ingested. Drinks vary in their resistance to the buffering effect of saliva. Studies show that fruit juices are the most resistant to saliva's buffering effect, followed by, in order: fruit-based carbonated drinks and flavoured mineral waters, non-fruit-based carbonated drinks, sparkling mineral waters; Mineral water being the least resistant. Because of this, fruit juices in particular, may prolong the drop in pH levels.
A number of medications such as vitamin C, aspirin and some iron preparations are acidic and may contribute towards acid erosion.
Cosmetic or functional intervention may be required if tooth surface loss is pathological or if there has been advanced loss of tooth structure. The first stage of treatment involves managing any associated conditions, such as fractured teeth or sharp cusps or incisal edges. These can be resolved by restoring and polishing sharp cusps. Then, desensitizing agents such as topical fluoride varnishes can be applied, and at home desensitising toothpastes recommended. Many restorative options have been proposed, such as direct composite restorations, bonded cast metal restorations, removable partial dentures, orthodontic treatment, crown lengthening procedures and protective splints. The decision to restore the dentition depends on the wants and needs of the patient, the severity of tooth surface loss and whether tooth surface loss is active. The use of adhesive materials to replace lost tooth structure can be performed as a conservative and cost-effective approach before a more permanent solution of crowns or veneers is considered.
Treatment may include smoothing, fluoride treatment, and crown restoration.
Treatment for TRs is limited to tooth extraction because the lesion is progressive. Amputation of the tooth crown without root removal has also been advocated in cases demonstrated on a radiograph to be type 2 resorption without associated periodontal or endodontic disease because the roots are being replaced by bone. However, X-rays are recommended prior to this treatment to document root resorption and lack of the periodontal ligament.
Tooth restoration is not recommended because resorption of the tooth will continue underneath the restoration. Use of alendronate has been studied to prevent TRs and decrease progression of existing lesions.
Since most toothache is the result of plaque-related diseases, such as tooth decay and periodontal disease, the majority of cases could be prevented by avoidance of a cariogenic diet and maintenance of good oral hygiene. That is, reduction in the number times that refined sugars are consumed per day and brushing the teeth twice a day with fluoride toothpaste and flossing. Regular visits to a dentist also increases the likelihood that problems are detected early and averted before toothache occurs. Dental trauma could also be significantly reduced by routine use of mouthguards in contact sports.
All impacted teeth, unless otherwise contraindicated, are considered for surgical removal. Thus, dental extractions will often take place. The type of extraction (simple or surgical) often depends on the location of the teeth.
In some cases, for aesthetic purposes, a surgeon may wish to expose the canine. This may be achieved through open or closed exposure. Studies show no advantage of one method over another.
The College of Registered Dental Hygienists of Alberta (CRDHA) defines a dental hygienist as "a health care professional whose work focuses on the oral health of an individual or community." These dental professionals aim to improve oral health by educating patients on the prevention and management of oral disease. Dental hygienists can be found performing oral health services in various settings, including private dental offices, schools, and other community settings, such as long-term care facilities. As mentioned above in the clinical significance section, plaque and calculus deposits are a major etiological factor in the development and progression of oral disease. An important part of the scope of practice of a dental hygienist is the removal of plaque and calculus deposits. This is achieved through the use of specifically designed instruments for debridement of tooth surfaces. Treatment with these types of instruments is necessary as calculus deposits cannot be removed by brushing or flossing alone. To effectively manage disease or maintain oral health, thorough removal of calculus deposits should be completed at frequent intervals. The recommended frequency of dental hygiene treatment can be made by a registered professional, and is dependent on individual patient needs. Factors that are taken into consideration include an individual's overall health status, tobacco use, amount of calculus present, and adherence to a professionally recommended home care routine.
Hand instruments are specially designed tools used by dental professionals to remove plaque and calculus deposits that have formed on the teeth. These tools include scalers, curettes, jaquettes, hoes, files and chisels. Each type of tool is designed to be used in specific areas of the mouth. Some commonly used instruments include sickle scalers which are designed with a pointed tip and are mainly used supragingivally. Curettes are mainly used to remove subgingival calculus, smooth root surfaces and to clean out periodontal pockets. Curettes can be divided into two subgroups: universals and area specific instruments. Universal curettes can be used in multiple areas, while area specific instruments are designed for select tooth surfaces. Gracey curettes are a popular type of area specific curettes. Due to their design, area specific curettes allow for better adaptation to the root surface and can be slightly more effective than universals. Hoes, chisels, and files are less widely used than scalers and curettes. These are beneficial when removing large amounts of calculus or tenacious calculus that cannot be removed with a curette or scaler alone. Chisels and hoes are used to remove bands of calculus, whereas files are used to crush burnished or tenacious calculus.
For hand instrumentation to be effective and efficient, it is important for clinicians to ensure that the instruments being used are sharp. It is also important for the clinician to understand the design of the hand instruments to be able to adapt them properly.
Ultrasonic scalers, also known as power scalers, are effective in removing calculus, stain, and plaque. These scalers are also useful for root planing, curettage, and surgical debridement. Not only is tenacious calculus and stain removed more effectively with ultrasonic scalers than with hand instrumentation alone, it is evident that the most satisfactory clinical results are when ultrasonics are used in adjunct to hand instrumentation. There are two types of ultrasonic scalers; piezoelectric and magnetostrictive. Oscillating material in both of these handpieces cause the tip of the scaler to vibrate at high speeds, between 18,000 and 50,000 Hz. The tip of each scaler uses a different vibration pattern for removal of calculus. The magnetostrictive power scaler vibration is elliptical, activating all sides of the tip, whereas the piezoelectric vibration is linear and is more active on the two sides of the tip.
Special tips for ultrasonic scalers are designed to address different areas of the mouth and varying amounts of calculus buildup. Larger tips are used for heavy subgingival or supragingival calculus deposits, whereas thinner tips are designed more for definitive subgingival debridement. As the high frequency vibrations loosen calculus and plaque, heat is generated at the tip. A water spray is directed towards the end of the tip to cool it as well as irrigate the gingiva during debridement. Only the first 1–2 mm of the tip on the ultrasonic scaler is most effective for removal, and therefore needs to come into direct contact with the calculus to fracture the deposits. Small adaptations are needed in order to keep the tip of the scaler touching the surface of the tooth, while overlapping oblique, horizontal, or vertical strokes are used for adequate calculus removal.
Current research on potentially more effective methods of subgingival calculus removal focuses on the use of near-ultraviolet (NUV) and near-infrared lasers, such as Er,Cr:YSGG lasers. The use of lasers in periodontal therapy offers a unique clinical advantage over conventional hand instrumentation, as the thin and flexible fibers can deliver laser energy into periodontal pockets that are otherwise difficult to access. Near-infrared lasers, such as the Er,CR:YSGG laser, have been proposed as an effective adjunct for calculus removal as the emission wavelength is highly absorbed by water, a large component of calculus deposits. An optimal output power setting of 1.0-W with the near-infrared Er,Cr:YSGG laser has been shown to be effective for root scaling. Near-ultraviolet (NUV) lasers have also shown promise as they allow the dental professional to remove calculus deposits quickly, without removing underlying healthy tooth structure, which often occurs during hand instrumentation. Additionally, NUV lasers are effective at various irradiation angles for calculus removal. Discrepancies in the efficiency of removal are due to the physical and optical properties of the calculus deposits, not to the angle of laser use. Dental hygienists must receive additional theoretical and clinical training on the use of lasers, where legislation permits.