Atraumatic restorative treatment (ART) is a method for cleaning out tooth decay (dental caries) from teeth using only hand instruments (dental hatchet and spoon-excavator) and placing a filling. It does not use rotary dental instruments (dental drills) to prepare the tooth and can be performed in settings with no access to dental equipment. No drilling or local anaesthetic injections are required. ART is considered a conservative approach, not only because it removes the decayed tissue with hand instruments, avoiding removing more tissue than necessary which preserves as much tooth structure as possible, but also because it avoids pulp irritation and minimises patient discomfort. ART can be used for small, medium and deep cavities (where decay has not reached the tooth nerve dental pulp) caused by dental caries.
In shallow to medium-sized cavities (lesions), the decayed tissue removal is carried out until the soft tissue (demineralised dentine) is completely removed and harder tissue is reached (firm dentine). In deeper cavities (lesions that reach more than two-thirds of dentine thickness on a radiograph), the removal of the decay must be carried out more carefully in order to avoid reaching the tooth's pulp (dental nerve). Soft tissue should be left on the cavity floor. The decision on how much decay to remove (whether to carry out the decay removal to firm dentine or stop when soft dentine has been reached) depends on the depth of the cavity (a filling needs to have a minimum thickness of material to remain strong); and the possibility of reaching the tooth's pulp (the nerve is exposed sometimes when deep cavities are accessed with rotary burs or vigorously with hand instruments, compromising the tooth's vitality).
Dental radiographs need to be taken to evaluate the depth of the cavity and extension of decay. If too deep and close to the pulp, only the soft decayed tissue is removed from the cavity floor to avoid the risk of pulp exposure.
ART is suitable for both primary (baby teeth) and permanent dentition (adult teeth) and has a large evidence base supporting it.
Background and history
ART was firstly introduced by the dentist Jo Frencken in 1985. It was introduced in Tanzania, where access to dental treatments using drills was restricted by limited dentist availability and a lack of electricity and or piped water. As a result, children's teeth generally decayed until they caused pain or infection and removal was required. At that time, the dentists tried to use only hand instruments to open and/or enlarge small cavities and selectively remove the decayed tissue, followed by the placement of a glass ionomer cement, an adhesive filling that also releases fluoride and helps the tooth's "recovery" from decay (remineralisation). This treatment was tested in clinical trials and found to be effective.
Although ART was initially developed in response to the needs of populations with less access to dental care, it had similar outcomes to more invasive treatments (local anaesthetic and drilling the tooth with dental bur). This means that it is suitable for use in any type of setting (from deprived communities to dental clinics) and it has been widely adopted into mainstream care. Due to its "atraumatic approach", it has also been proven to be beneficial for patients with dental anxiety or learning disabilities, even where there is adequate dental care, as neither drilling nor local anaesthetics are required.
During the International Caries Consensus Collaboration (ICCC) meeting held in Leuven in 2015, ART was recommended by an international group of experts in cariology, restorative and paediatric dentistry as an option to treat decayed primary and permanent teeth with decay where restorative options were indicated, such as cavities that were difficult to clean using only toothbrushes and fluoride toothpaste.
Concept There are two different ART procedures with different aims: preventive (ART fissure sealant for non-cavitated teeth); and restorative (ART filling for decayed and cavitated teeth)
Preventive
Adult teeth that erupt behind the baby back teeth have deep grooves (fissures) and are more susceptible to accumulating food debris and dental plaque which can stagnate and lead to decay. They are also difficult to toothbrush properly. While they are erupting, they are very susceptible to decay and it is very difficult to keep them dry enough to use a resin-based sealant material successfully. However, sealing the tooth pits and fissures helps make cleaning the tooth easier and stops the accumulation of plaque biofilm, so a high viscosity glass ionomer cement (HVGIC) is used to seal these teeth, covering the pits and fissures. This is done by cleaning the tooth, placing a layer of HVGIC over the back teeth and using finger pressure to keep it in place and dry until the HVGIC material sets. Excess material is removed. If necessary, it is adjusted to fit the bite using hand instruments.
Restorative
Where the enamel (the hard outer surface of the tooth) has cavitated or even has a small breach due to tooth decay, the cavity can be enlarged with special hand instruments when necessary to enable access to the soft decayed tooth tissue. After removing as much decay as necessary, the cavity is cleaned with water, dried and filled with the HVGIC. The filling seals the cavity preventing food debris and dental plaque stagnating inside the cavity. It also promotes remineralisation of the dental tissues affected by decay. When the cavity is sealed any decay and bacteria that has been left on the floor of the cavity cannot get access to oxygen and sugar and will not continue.
Effectiveness of sealants
The retention rate of ART sealants using HVGIC has improved significantly compared to low and medium viscosity-viscosity glass-ionomers previously used. ART sealants appear to have a high caries preventive effect. ART/HVGIC sealants are effective in controlling dentine-carious-lesion development in pits and fissures. Occurrence of secondary carious lesions are rare at the tooth-restoration interface of single-surface ART/HVGIC restorations in primary teeth.
ART sealants versus resin-based sealants Compared to resin composite sealants, ART/HVGIC sealants appear to be more effective in erupting permanent molars where moisture control is hard to achieve due to the water-like nature of the glass-ionomer material and less sensitive technique. However, moisture control should always be attempted as much as possible for a better material survival. The full- and partial-retention survival of ART/HVGIC is lower compared to resin-based sealants. 4 systematic reviews and meta-analyses, one of which is a Cochrane review. show that there is no difference in terms of dentine caries-lesion preventive effects between both types of sealants.
Indications ART fillings can be used in multiple situations, such as for single-surface cavities in primary (baby teeth) and permanent (adult) teeth, and multiple-surface cavities in primary teeth, if no other option is available or suitable (e.g. Hall Technique). They can also be used for non-frankly cavitated lesions (presenting a shadow under the enamel) that are not suitable for sealing. In addition, the procedure is particularly suitable for children, uncooperative, disabled and anxious patients.
Contraindications
ART fillings should not be used when there is:
Swelling or a fistula near the decayed tooth; Pulpal exposure (the nerve of the tooth is visible); History of pain from the teeth to be treated; Lesions that cannot be accessed with hand instruments (proximal side); Multi-surface cavities in permanent teeth; and Teeth that are badly broken down, which are unrestorable.
Effectiveness
ART is effective for restoring single-surface cavities in both primary and permanent dentition and should be considered as the preferred option. ART shows higher failure rates for multi-surface carious lesions restorations when compared to single-surface lesions. Meta-analysis concluded that the mean annual failure rate for multiple-surface ART restorations in primary teeth are still high. Very few studies have investigated the survival (success) of ART restorations in multiple-surface cavities in permanent teeth, and it is not possible to draw conclusions yet. ART preserves the tooth structure as only the soft demineralised tissue in deep cavities is removed. Low pain and discomfort are experienced. Dental anxiety is lower when performing ART when compared to conventional drill-and-fill methods.
Comparison with conventional fillings Systematic reviews and meta-analyses show that there are no differences between ART/HVGIC restorations in terms of longevity in primary teeth (for both single- and multiple-surface lesions) compared to the conventional methods using either amalgam or resin composite. Systematic reviews and meta-analyses have shown that there are no differences between ART restorations for single-surface lesions in permanent teeth when compared to conventional filling methods. However, a 2017 Cochrane Review on ART could not draw any conclusions about ART/HVGIC restorations compared to amalgam or composite restoration due to the low quality of the evidence.
Evidence
Below is the summary of success of ART/HVGIC restorations in different type of cavities. Type of cavities using ART/HVGIC Evidence of restoration successSingle-surface in posterior primary teeth (baby back teeth) for first 2 yearsHigh (survival percentage = 94.3% [± 1.5])Multiple-surface in posterior primary teeth for first 2 yearsMedium to low (survival percentage = 65.4% [± 3.9])Single-surface in posterior permanent teeth (back adult teeth) for first 3 yearsHigh (survival percentage = 87.1% [± 3.2])Multiple-surface in posterior permanent teethNo conclusion can be drawn due to insufficient data
Although originally developed for use in developing countries, due to its "atraumatic" approach, ART has become increasingly well accepted in developed countries. Although ART alone is insufficient to improve the oral health of people in low- and middle-income countries in a sustainable manner, the World Health Organization (WHO) Collaborating Centre of Oral Health Care Planning and Future Scenarios in Nijmegen has included it in the Basic Package of Oral Care (BPOC). This aims to improve the oral health of deprived communities in a cost-effective manner. This package comprises three components:
Oral urgent treatment (OUT) – relief of oral pain (through extracting non-repairable painful teeth; and other urgent treatment), first aid for oral infections and dental trauma; Affordable fluoride toothpaste (AFT) – through oral health promotion and prevention of caries and gingivitis through toothbrushing using toothpaste fluoride; and Atraumatic restorative treatment (ART) – operative and preventive caries management through the use of the ART approach (sealants and fillings), introduction of dental care to young children and patients with dental fear or anxiety, presenting with mental or physical disabilities or home-bound elderly and those stay in nursing homes; and ART as an intermediate treatment to stabilize conditions in high-risk caries clinical situations.
ART in multiple-surface cavities
ART/HVGIC restorations can be successfully used in single-surface lesions in both primary (SDCEP) and permanent teeth. For multi-surface lesions (tooth decay that has spread across more than one surface of the tooth), systematic reviews and meta-analyses show that the mean failure rate of ART/HVGIC restorations is higher than occlusal lesions and with a wide range of success. In these cases, there is evidence that the Hall Technique may be more successful.