Is a laser more effective at removing tooth decay than a traditional drill?

Dentist using a modern diode dental laser for periodontal care. Both wearing protective glasses, preventing eyesight damage. Periodontitis, dental hygiene, preventive procedures concept.

Dental decay is a cavity formation in teeth resulting from the destruction of dental tissue caused by bacteria under certain conditions, including poor oral hygiene and excessive sugar intake. Symptoms may include pain and difficulty with eating, and complications may include tooth loss, infection or inflammation of the gum. Rotating drills are traditionally used to remove decay. However, this mechanical tool may have unexpected side effects, such as the removal of too much or too little decay, in addition to discomfort due to pain, noise and vibration. Laser therapy is a potential alternative to a mechanical drill.

What was the research?

A systematic review to examine whether there is an advantage to laser therapy for the removal of decay in teeth and patient pain, compared to a traditional drill, in children, adolescents and adults.

Who conducted the research?

The research was conducted by a team led by Alessandro Montedori from the Regional Health Authority of Umbria, Italy, on behalf of Cochrane Oral Health. Iosief Abraha, Massimiliano Orsa, Potito Giuseppe D’Errico, Stefano Pagano and Guido Lombardo were also on the team.

What evidence was included in the review?

Nine randomised controlled trials were selected for inclusion in this review. They were conducted between 1998 and 2014. The evidence in the review is up to date as of 22 June 2016. The trials involved a total of 662 participants, with 1498 teeth treated. Three studies were conducted in the USA, one in Taiwan, one in China, one in Bulgaria, one in Germany, one in Turkey and one in the UK. The population consisted of both children and adolescents in four trials, only adults in four trials, and both children/adolescents and adults in one trial.

What did the evidence say?

Despite the number of included studies, only a few trials adequately and completely reported information on the primary outcomes. Two trials reported on removal of decay, and there was not enough evidence to conclude that either lasers or drills were better at decay removal. Only five trials reported on episodes of pain, which was significantly reduced in people treated with lasers. There was no difference in terms of side effects, such as inflammation or death of dental pulp, between the two interventions.

How good was the evidence?

The overall quality of the evidence for the nine studies was low. Only one study adequately randomised participants, and none of the included studies was at low risk of bias. This review highlights the need for high-quality studies comparing laser therapy and mechanical drills in the treatment of dental decay.

What are the implications for dentists and the general public?

Despite the inclusion of a fair number of studies in this systematic evaluation, only two studies with limited sample size assessed and provided data for the outcome removal of caries. The evidence was limited to either claim or refute a difference between laser and drill treatment for caries removal. Four studies that evaluated pain showed that laser treatment may have some advantage in terms of limiting pain in children, adolescents and adults. However, the quality of the evidence was low.

What should researchers look at in the future?

Additional well-designed randomised trials to evaluate the efficacy of laser therapy compared to drill-based treatment of caries are warranted. These trials will need to consider removal of caries and participant perception (including pain, discomfort and the need for anaesthesia), together with duration and marginal integrity of restoration, as the primary outcomes. These trials should have an extended follow-up of at least 2 years in order to evaluate the integrity and retention of restoration. Cost analysis should also be considered.


Montedori A, Abraha I, Orso M, D’Errico PG, Pagano S, Lombardo G. Lasers for caries removal in deciduous and permanent teeth. Cochrane Database of Systematic Reviews 2016 , Issue 9 . Art. No.: CD010229. DOI: 10.1002/14651858.CD010229.pub2.

This post is an extended version of the review’s plain language summary, compiled by Anne Littlewood at the Cochrane Oral Health Editorial Base.