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Clinical Studies | Convergent Dental


Patient and Clinician Experiences When Using a CO2 Laser for Cavity Preparations: Lessons learned from Prospective Clinical Research

Gregory Schuster , Marc Cohn, Gina Agostini-Walesch, Alexander Carroll and John C. Mitchell

ABSTRACT (Click here for full article)

This prospective clinical study evaluated the experiences and preferences of both patients and clinicians when performing class I–V cavity preparation procedures using a 9300 nm CO2 laser without anesthetic. A total of 233 procedures were performed on 103 patients. Following treatment, patients were asked to describe discomfort/pain levels and preferences for future treatment with either laser treatment or traditional therapy. Additionally, clinicians were asked to rate their experiences with the procedures in three technical domains: speed, ease-of-use, and precision. In total, 98% of patients preferred laser treatment to traditional therapy and 93% of all procedures performed were completed with no anesthesia. Younger patients and patients receiving multiple restorations reported significantly higher discomfort, though discomfort scores were very low overall (below 3 on a 10-point pain scale). While there were significant differences in clinician experiences, each clinician reported having generally high satisfaction using the laser with respect to speed, ease of use, and precision. In conclusion, the 9300 nm CO2 laser provides clinicians a viable option for cavity preparations in dentistry as evidenced by high rates of anesthesia-free procedures with low reported discomfort, the fact that nearly all patients would opt for laser use on future cavity preparations, and generally positive experiences reported by clinicians


This prospective clinical study was approved (approval #AZ1059) by the Midwestern University Institutional Review Board. All patients requiring class I–V cavity preparations and presenting at the Dental Institute were invited to participate in the study, provided they met the study inclusion criteria. Between August 2017 and April 2019, 103 patients received 233 resin-bonded composite restorations. Each participant was invited to enroll based on the following inclusion criteria: 1. Having class I, II, III, and/or V carious primary lesions on previously unrestored teeth or having recurrent caries that did not require removal of amalgam. 2. Willingness to begin the preparation without anesthetic. 3. Participants requiring multiple procedures with the laser would be seen to in one appointment. Participants varied in their experience with traditional handpieces with respect to previous dental treatment.


The demographics of the final sample population were 53% female with a mean age of 51.44 ± 20 years (mean age females: 53.31 ± 19.9 years; mean age males 48.6 ± 20 years). In total, 57.3% of study participants were receiving treatment on more than one tooth. There was no significant difference in discomfort by gender (p = 0.672, F = 0.179).
Individuals receiving multiple preparations reported significantly higher discomfort than those receiving a single preparation (p = 0.0267, F = 5.065). However, overall discomfort scores were low for both groups (mean discomfort less than 2 of 10, see Figure 1).


The 9300 nm CO2 laser provides a new option to Er:YAG and Er:YSGG lasers for performing precision cavity preparations in operative dentistry. Patient experiences demonstrated preference for CO2 laser cavity preparations versus traditional handpiece cavity preparations. In addition, patients reported a high incidence of pain-free dental treatment without the use of local anesthesia. Clinician experiences show preference for the use of the CO2 laser compared to traditional handpieces for cavity preparations conducted in this study. They all reported a preference for this laser compared to traditional handpieces with regard to speed of preparation, ease of use, and precision. Based on overall favorable experiences for patients and clinicians, this laser appears to be a preferred option for anesthesia-free cavity preparations.

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