Article in review:
Convissar RA. The top ten myths about CO2 dental lasers.Dent Today. 2009 Apr;28(4):68, 70, 72-6; quiz 77.
In this publication, a pioneer in dental lasers and oral laser surgery, Dr. Robert A. Convissar reviews the CO2 dental laser applications. Dr. Convissar has more than two decades of experience with CO2, Nd:YAG, Diode and Erbium wavelengths. He has presented more than 300 seminars on five continents and written numerous papers and textbooks about laser dentistry. He practices cosmetic, restorative and laser dentistry at his private practice in New York City, where he also serves as Director of Laser Dentistry at New York Hospital Queens.
Myth #1: The CO2 laser is too powerful for general dentistry or periodontal therapy.
The electromagnetic spectrum illustrates that the CO2 laser wavelength (10.6 micrometers) actually carries less energy per quant than any of the other wavelengths used in dentistry. However, water molecules absorb this wavelength extremely well and, since oral soft tissue is 90-97% water, the CO2 laser wavelength is the one best absorbed by soft tissue. This means that the CO2 laser isn’t the most powerful, but instead has “the most efficient wavelength for use on soft tissue in dentistry due to its superior absorption by soft tissue.”
Myth #2: Periodontists, in general, have nothing good to say about CO2 lasers.
Speaking in particular of the American Academy of Periodontology (AAP) and the Journal of Periodontology, the author cites numerous “peer-reviewed papers by some of the leading periodontists in the United States, including certain articles published in the Journal of Periodontology” (See -). The author notes CO2 laser surgery benefits, including “control of surgical and post-surgical bleeding; less adjacent tissue damage; reduced postoperative edema; decreased post-surgical pain; better access to some surgical areas; and decreased or eliminated wound contraction and scarring.”
Myth #3: There is nothing a CO2 laser can do that can’t be done with a scalpel.
Focusing on de-epithelialization, the author writes, “one goal of periodontal surgery is the regeneration of osseous structure and creation of a true soft-tissue connection to the root surface, rather than a long junctional epithelium.” Among numerous examples and case studies, The Research, Science and Therapy Committee of the AAP concludes that “the CO2 laser has been shown to enhance periodontal therapy through an epithelial exclusion technique in conjunction with traditional flap procedures, and when the CO2 laser is used to de-epithelialize the mucoperiosteal flap during surgery, it enhances reduction in periodontal probing depths.”
Myth #4: CO2 lasers cannot be used on root surfaces without causing extensive charring, cracking, and damage to the root surface.
The Journal of Periodontology evinces the exact opposite, stating that applying dental CO2 laser energy directly on root surfaces further increases the success of periodontal surgery. For example, Pant et al. compared tetracycline, hydrogen peroxide, citric acid, EDTA and CO2 laser energy to condition root surfaces, with the end goal of enhancing attachment of periodontal ligament fibroblasts to periodontally involved root surfaces. With 84 teeth examined with a SEM, the researchers concluded that CO2 laser irradiation was the most efficient technique, “showing consistently good cell attachment, with the highest mean values of attachment.” This section also stresses the value of good CO2 laser training, stating “the most skilled dentists in the world will not obtain the best results, unless they are properly trained to use the correct instrument in the correct manner with the correct parameters.”
Myth #5: CO2 lasers can’t be used near implants, because of implant deintegration.
Convissar’s article points out that “this myth is not supported by peer-reviewed literature.” For example, Deppe et al. placed 60 implants in beagle dogs and induced peri-implantitis. The subsequent lesions were decontaminated in three different ways – air abrasion alone; air abrasion with CO2 laser; CO2 laser only. The researchers concluded that, “the CO2 laser is safe” and suitable for peri-implant gingival treatment.
Myth #6: CO2 lasers have very little use in restorative or cosmetics-oriented practices.
A survey from May 2005 concludes that an amazing 87% of laser dentists use a dental laser for “cosmetic gingival contouring, including around crown and laminate margins.” 81% use a laser for gingival retraction/troughing. A study describes the use of CO2 lasers for sulcular gingivoplasty and lists the many advantages of lasers over conventional procedures, like a healthier gingival sulcus. The author also includes before and after pictures of a laser gingivoplasty case to restore lingually positioned canine tooth, evincing an excellent emergence profile from surgically enhanced smile line.
Myth #7: CO2 lasers are useless for fine tissue procedures, such as smile design.
A study by Dr. Sun shows that CO2 lasers can vaporize soft tissue precisely and quickly for cosmetic dentistry. Dr. Adams and Dr. Pang describe the use of a CO2 laser for smile design, “to correct a patient’s presentation of short, wide, maxillary teeth.” Dr. Convissar incorporates his own case studies to further contradict the myth.
Myth #8: Purchase an “all tissue laser” instead of a CO2 laser, since CO2 lasers are good for soft tissue, but not operative dentistry.
There is no ideal “all-purpose bur” for all dental procedures, from Class I decay to Class V decay, from laminate preparations to full crown preparations, etc. It is possible to use one bur (a 557 cross-cut fissure bur) for all procedures, but it is far from ideal. Dr. Convissar advises that, “although a well-trained laser dentist may be able to use one wavelength for both hard and soft-tissue procedures, there is currently no wavelength on the market that will work equally well on both hard and soft tissues.” However, CO2 lasers are “ideal for soft-tissue surgery” and 45 years of peer-reviewed literature supports soft tissue laser use. Dr. Convissar also notes that they are half the cost of all-tissue lasers (i.e. erbium).
Myth #9: CO2 lasers always char tissue.
In the 1980s, when the CO2 laser surgery was in its infancy, the original CO2 laser temporal emission modes were either CW or gated pulse. The SuperPulse mode, invented in the 1990s, features high peak power and fast pulsing, so CO2 lasers no longer deliver long pulses of laser energy that can overheat and char tissue. SuperPulse CO2 lasers minimize collateral heating of adjacent tissue and speed the healing process.
Myth #10: All lasers, including CO2, are too expensive.
A 2005 survey directly challenges this return on investment (ROI) myth. When asked how revenue was increased as a result of purchasing a CO2 laser, 67% of those using this dental laser cited new procedures that were previously referred out to specialists, 66% cited increased productivity, more than one-third cited the acquisition of new patients, and one-quarter of laser dentists cited the ability to perform higher-end procedures.
- Pick RM, Pecaro BC, Silberman CJ. The laser gingivectomy. The use of the CO2 laser for the removal of phenytoin hyperplasia. J Periodontol. 1985;56:492-496.
- Pick RM, Pecaro BC. Use of the CO2 laser in soft tissue dental surgery. Lasers Surg Med. 1987;7:207-213.
- Israel M. Use of the CO2 laser in soft tissue and periodontal surgery. Pract Periodontics Aesthet Dent. 1994;6:57-64.
- Research, Science and Therapy Committee of the American Academy of Periodontology. Lasers in periodontics. J Periodontol. 2002;73:1231-1239.
- Cobb CM. Lasers in periodontics: a review of the literature. J Periodontol. 2006;77:545-564.