By Noel Berger DVM, MS For The Education Center
Originally Published In Veterinary Practice News, November 2018 –Download as a PDF
Using a CO2 laser for oral surgery is a revolutionary concept today just as using digital imaging instead of emulsion technology was 20 years ago. It can be difficult to imagine going back to using chemistries to process radiographs, and it may be just as difficult to imagine using cold, hard steel for oral surgery instead of using a CO2 laser for oral surgery! Research from human periodontists who use animal models of healing has shown that using a surgical CO2 laser creates an enhanced environment to create stronger attachment of gingiva to the jaw and facial bones.
The gingiva of dogs and cats is composed of both epithelial tissue and fibrous connective tissue possessing a rich capillary bed and abundant sensory innervation. The 10.6 um wavelength of CO2 laser energy is absorbed extremely efficiently by these tissues, allowing for accurate, precise, clean, and pain-free incisions using very low power. The result is the creation of a mucoperiosteal flap that can be created with a minimal amount of tissue trauma, thus reducing surgery time and increasing the speed and quality of healing.
Mucoperiosteal flaps are most commonly created for facilitating exodontia, or extracting diseased teeth and supporting bone. This procedure is performed under general anesthesia, radiographs are taken and analyzed, and local nerve blocks are recommended. An envelope flap can be created by gently mobilizing the gingiva apically in relation to the tooth. This exposes the underlying bone using a periosteal elevator to gently pry away the tissue using a slow twisting motion. When needed, the CO2 laser is used to create a triangle flap (three corners) or a pedicle flap (four corners). The laser-assisted incision is made approximately as long as the tooth root and should be angled so the base of the flap is wider than the apex. I generally use 0.25 mm spot size, 2-4 W SP (superpulse) at 75 percent duty factor. An angled handpiece or a straight handpiece with a scalpel-like grip can be used. The surgeon will immediately notice that the surgical field is clean and dry because the capillaries and lymphatics have been sealed by the laser-tissue interaction.
Following satisfactory complete tooth-root extraction, a new CO2 laser technique can be employed to enhance the rate and quality of mucoperiosteal flap adhesion to the underlying alveolar bone. Numerous studies in the human periodontology literature[4-8] support using a de-epithelialization technique prior to suturing, to create better quality re-adhesion. Prior to the closure of any of the three previously mentioned mucoperiosteal flaps, I have routinely used a 0.25 mm spot size, 2 W CW (continuous wave) RP (repeat pulse) 5 Hz, 60 msec duration, at a distance of approximately 10 mm to defocus the incident beam. This technique allows the surgeon to move the beam over the inside of the flap at a hand speed that causes de-epithelialization without perforating the flap or eliminating tissue perfusion and blood flow. These parameters are imprecise, as surgeons will have unique patterns of exposure to complete the task. A minimum of targeted overlap should be employed. The goal of healing is to create an environment where rapid epithelial migration is inhibited and stronger fibroblast migration is promoted. Following CO2 laser exposure of the inside of the gingiva, these qualities are realized.
In one example, a diseased upper right canine tooth (104) of a 14-year-old female spayed Schnauzer-mix dog was extracted. She had a sudden onset of severe halitosis, pain with food prehension, purulent nasal discharge, and mild upper right facial swelling. Radiographs revealed an apical abscess and root canal therapy was considered impractical. An abbreviated surgical sequence is outlined in the Figure 1 image series.
In a second example, a two-year-old male neutered great Pyrenees dog presented for a dental cleaning at the owner’s request. During gingival probing, a deep gingival pocket was identified at the buccal aspect of the upper left second incisor tooth (202). Radiographs of the teeth and supporting alveolar bone were normal. It was decided not to extract a healthy tooth, and to preserve the supporting gingiva by CO2 laser-assisted periodontal surgery. The surgical sequence is outlined in the Figure 2 image series.
In both examples, an envelope flap was created using gentle prying action to separate the gingival periosteum from the underlying bone. Vitally important to this technique, a CO2 laser was used to create the tension-relieving gingival incisions. The result was a cleaner, drier surgical field that was less painful to the patient upon recovery. A CO2 laser was then used to de-epithelialize the inside surface of the mucoperiosteal flap before suturing. While not required for the procedure, I have found rapid acceptance of this CO2 laser periodontal surgery technique adapted from human dentists.
Veterinary dentistry and oral surgery have evolved to specialty level for several decades now, and general practitioners may utilize some of these advanced techniques to provide new solutions to common problems faced by our patients. The use of a CO2 laser in oral surgery is an efficient and beneficial technique to create stronger bonds between the gingiva and bone during the healing phase following surgery. It is also an opportunity to strengthen the bond you have with your patients and clients by providing a higher level of care. Our clients are being treated with these procedures at their dentists’ offices, and I believe they will embrace having their pets treated this way, too. All it takes is knowledge, communication, compassion, and a little bit of technology to make it all adherent.
About the Author
Dr. Berger is a graduate of Cornell University (1988, 1989) for both his DVM and MS in clinical sciences. He has been a certified diplomate of the American Board of Laser Surgery in veterinary surgery since 2000, and he has written a textbook on the subject. He has lectured nationwide on laser physics and clinical applications for small animal veterinarians and is available for consultation and training at Quail Hollow Animal Hospital, Wesley Chapel, Fla.
- Cobb C. Lasers in Periodontics: A Review of the Literature. J Periodontology. 2006:77:545-564.
- Lommer M. Principles of Exodontics. In: Oral and Maxillofacial Surgery in Dogs and Cats. Eds. Verstraete F, Lommer M. 2012, Saunders Elsevier. Ch. 11:97-114.
- Low S. Lasers in Surgical Periodontics. In: Principles and Practice of Laser Dentistry, 2nd edition, Ed Convissar R. 2016, Mosby Elsevier. Ch. 4:53-69.
- Centty I, Blank L, Levy B, et al. Carbon Dioxide Laser for De-Epithelialization of Periodontal Flaps. J Periodontology. 1997;Aug.;763-769.
- Crespi R, Barone A, Covanin U, et al. Effects of CO2 Laser Treatment on Fibroblast Attachment to Root Surfaces: a SEM Analysis. J Periodontology. 2002:73:1308-1312.
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- Rossman JA, Parlar A, Ghaffar KA, et al. Use of the Carbon Dioxide Laser in Guided Tissue Regeneration Wound Healing in the Beagle Dog. SPIE Proceedings, 1996, April 23, Vol. 2672.
This Education Center article was underwritten by Aesculight of Bothell, Wash., the manufacturer of the only American-made CO2 laser.