Examining evidence for routine scale and polish treatment – an updated review
The Cochrane Review 'Routine scale and polish for periodontal health in adults' was carried out by authors working with Cochrane Oral Health to assess the effects of routine scale and polish treatments for healthy adults and to establish whether different time intervals between treatments influence these effects. The review had aimed to compare the effectiveness of the treatment when given by a dentist compared to a dental therapist or hygienist, but there were no studies evaluating this comparison.
This review updates the version published in 2013 and includes two studies with a total of 1711 participants. Both studies involved adults without severe periodontitis who were regular attenders at dental appointments in the UK. The studies were conducted in general dental practices, which is the most appropriate setting to evaluate 'routine scale and polish' treatments.
Dr. Thomas Lamont, lead author explains,
“This evidence could help patients and dental professionals make informed decisions about routine scale and polish treatment - which can be also known as ‘prophylaxis’, ‘professional mechanical plaque removal’ and ‘periodontal instrumentation’ - as it questions the effectiveness of the traditional delivery of routine scale and polish treatment in primary dental care.
“The studies found that regular planned scale and polish treatments didn’t reduce the early signs of gum disease more than scale and polish delivered only when the dental professional judged it necessary or it was requested by the patient. The tartar levels were slightly more reduced with scheduled treatments, but it’s uncertain if this small difference would be considered important by patients or their dentists.
“Participants receiving six-monthly and 12-monthly scale and polish treatments reported feeling that their teeth were cleaner than those who were not scheduled to receive treatment, but the evidence is low quality, and the studies didn’t find any difference between the groups in terms of quality of life.
“It should be noticed that neither of the studies measured side effects, such as damage to tooth surfaces and tooth sensitivity, changes in attachment level, tooth loss or bad breath, and available evidence on the costs of the treatments is uncertain.”
Interview with – Dr Thomas Lamont, lead author of this Cochrane review
Please describe yourself and your Cochrane Group?
I graduated in dentistry from Glasgow University in 2008 and went on to complete a PhD at the University of Dundee. I am currently a Clinical Research Fellow and Honorary Specialty Registrar in Restorative Dentistry at the University of Dundee. I am also a clinical editor at Cochrane Oral Health, which was founded in 1994. For over 20 years, Cochrane Oral Health has been producing high-quality, relevant systematic reviews that can improve oral health care and oral health. We currently have 163 active reviews on the Cochrane Library, as well as 35 protocols for reviews currently in progress.
What is the background to this review and the update?
Many adults in high-income countries will be used to having a ‘scale and polish’ when they go to the dentist. It is intended as a supplementary form of plaque removal in addition to oral hygiene undertaken regularly at home by patients, with the aim of reducing the risk of gum disease.
The first Cochrane Review of regular scale and polish treatment was conducted in 2004 and showed that there was very little evidence to go on. In the review’s conclusions, the authors recommended that a trial be conducted to find out whether routinely providing a scale and polish treatment to people who had relatively healthy mouths and tended to visit the dentist regularly actually had an impact on their long-term oral health, and specifically on periodontal disease. NIHR picked up on this, and Professor Jan Clarkson of the University of Dundee collaborated with Professor Craig Ramsay of the University of Aberdeen, together with colleagues from several other universities, to apply for HTA funding to run such a trial. I joined them as the Clinical Research Fellow on the trial, which was known as ‘IQuaD’ in 2011 and subsequently became involved in updating theCochrane Review. IQuaD was completed in 2017, and the findings were published in 2018 (https://www.journalslibrary.nihr.ac.uk/hta/hta22380/#/abstract)
(Improving the Quality of Dentistry (IQuaD): A cluster factorial randomised controlled trial comparing the effectiveness and cost-benefit of oral hygiene advice and/or periodontal instrumentation with routine care for the prevention and management of periodontal disease in dentate adults attending dental primary care. Health Technology Assessment Volume 22, Issue 38, July 2018)
Why is an update of the review important?
As Cochrane’s mission is to promote evidence-informed health decision-making by producing high-quality, accessible systematic reviews and other synthesised research evidence, there is a commitment to ensure Cochrane Reviews are kept up-to-date by identifying and incorporating new evidence. The IQuaD trial reached some strong conclusions that we felt should be combined with the existing evidence and shared widely.
What are the main implications of this research?
This review questions whether it is necessary for scale and polish to be delivered routinely, that is, on a standard schedule of every 6 or 12 months. Many people like the clean feeling that they get from a scale and polish treatment every six months, but it is not clear that there is any real clinical benefit in terms of reducing gum disease. The updated review shows that providing scale and polish treatment when the dentist deems it appropriate or when the patient requests it, does not result in poorer oral health outcomes after 2 to 3 years than providing scale and polish treatments on a predetermined 6- or 12-monthly schedule.
It is important to point out that the participants in the two trials included in the review had relatively healthy mouths; none of them had severe periodontitis. It is also important to point out the trials were conducted in the UK. In other high-income countries, the treatment may be known as “prophylaxis”, “professional mechanical plaque removal” or “periodontal instrumentation”, and it is reasonable to assume that the findings would be the same.