The aim of this study was to evaluate the excavation time, patients´ experiences, pulpal reactions and survival of fillings when carious tissue was removed with Er:YAG laser compared to rotary bur. A prospective, single-blind, randomized and controlled investigation was performed. Patients with at least two primary caries lesions radiographically assessed as the same size were recruited. In each patient one cavity was excavated with rotary bur and one with Er:YAG laser technique. The time requested for excavation and local anaesthesia were measured. The prevalence of postoperative symptoms, pulpal vitality and the quality of fillings will be investigated during two years after the excavation occasion.

The study is a prospective, single-blind, randomized and controlled investigation. Patients between 15-40 years with at least two primary caries lesions radiographically assessed as the same size were recruited. In each patient one cavity was excavated with rotary bur and one with Er:YAG laser technique after a randomized allocation of the lesions to one of the intervention methods. The time requested for excavation to hard/firm dentin and local anaesthesia were measured. Directly after each treatment a questionnaire focusing on the experiences of the current treatment and if the laser method will be chosen in the future was answered. Postoperative pain was measured with a questionnaire one week after the treatment. Six, 12 and 24 months after the fillings were made an evaluation of pulpal status and the quality of the fillings will be performed.

Inclusion Criteria:

• patients should be between 15 and 40 years,
• at least two lesions with primary caries estimated as being of equal size, and needed to be treated, in bite-wing radiographs, and
• comparable pairs of cavities should be located on either occlusal or approximal surfaces.
• the lesions should not involve the inner third of the dentin.

Exclusion Criteria:

• patients with severe general diseases ( ASA>2) (30),
• cognitive or intellectual disabilities,
• patients who required sedation or general anaesthesia, and
• teeth with periapical pathology, a root filling or non-vital teeth.

IPD are not planned to be shared

The outcome assessor have not met the patient before assessing the outcome. No information about which excavation method used is available.