There are many advantages of using lasers in periodontal therapy, but the key point is that these are adjuncts to conventional therapy and not a replacement. The first line of any periodontal therapy should include implementing a prescriptive oral hygiene protocol for the patient and carrying out supra-and subgingival debridement.
The aim of treatment is to reduce oral inflammation, eliminate pockets, and ideally achieving a gain in clinical attachment level.
Here, we look at two types of lasers used in periodontal therapy – the diode (940nm wavelength, Epic 10, Biolase), and Er-Cr: YSGG Waterlase MD laser (2780nm). They can be used separately, or together as dual-wavelength therapy.
The diode laser has a particular affinity for pigment and is a great tool for achieving haemostasis, due to its absorption by haemoglobin in the blood. Its other advantage is that periodontal bacteria are mostly pigmented and, therefore, the diode effectively ‘targets them’ so can be used in periodontal pockets to kill periodontal pathogens.
Its use following subgingival debridement is, therefore, to reduce bacteremias, to help prevent cross-contamination of periodontal pockets through probing or scaling and to help reduce the risk of contamination of periodontal pockets through probing or scaling and to help reduce the risk of periodontal abscesses after hygiene visits for patients.
Studies have suggested that, by killing the bacteria in the pockets, the pocket resolution may be greater than conventional treatment alone.
If the tip is used uninitiated, then the bacteria are killed through cell lysis of the cell membranes, without significant ablation of tissue. This makes it ideal for use by hygienists and therapists. Once the tip has become initiated (in contact with blood for a while), then it can be used to ablate the pocket epithelial lining and remove granulation tissue.
This is known as laser curettage and becomes a grey area as to whether only dentists or hygienist and therapists are permitted to use it in this way.
The Er-Cr: YSGG, referred to from now on as the Waterlase, uses hydroponics to ablate tissues. This effectively means that water does the cutting. This wavelength has a particular affinity for both hydroxyapatite (tooth and bone) and water (the water in the soft tissues).
As the laser beam hits the tissues, laser energy turns the water in individual cells to vapour, causing them to explode (which we see as tissue being cut). It does this without heat, pressure or vibration, so no damage is caused to the tissues.
Also, the depth of necrosis to the surrounding tissues is only 5-10 cell layers, compared to 100-300 cells if a scalpel is used, and 1000-1500 with electrosurgery. The diode affects 15-25 cell layers. The implications of this mean that tissues are ‘cut’ or ablated with very little damage, which leads to faster and much less painful healing.
Like the diode, the Waterlase can be used in periodontal pockets. The Waterlase has radial firing tips, so the laser beam is projected laterally, which makes them ideal for use in pockets.
This laser can be used for removal of biofilm, removal of calculus, removal of granulation tissue and the pocket lining, and is also used outside the pocket to disrupt the epithelium.
This follows the principals of new attachment formation, delaying the downgrowth of epithelium, to allow time for formation of new connective tissue as part of the healing process rather than that of a long junctional epithelium. Studies have found that indeed, regeneration (new cementum, bone and periodontal ligament) have formed after scaling and root planning, followed by use of the Er-Cr: YSGG laser.
The protocol used would consist of carrying out conventional therapy, and then entering the pockets with a radial firing tip to treat the pockets. You can then also use the diode to further reduce bacterial load and have the added advantage of LLLT (for pain relief, accelerated healing, and sensitivity).
The first case is that of a 32-year-old female, who was treated non-surgically using ultrasonics, followed by laser treatment in the same visit with the Waterlase. The pocket resolution after just two months is almost complete, and because there seem to be bony changes, the teeth also moved back into position over the course of a year.
The suggestion is also that stability following laser treatment is perhaps better than following conventional treatment. The radial firing tips allow you the re-shape the tissues at the same time, so you can thin tissues and improve access for oral hygiene purposes with simultaneous gingivectomies in the same visit.
This is otherwise something that would have to be done through periodontal surgery. Indeed, the tips are also up to 14mm long and thinner than a periodontal probe, so can clean deeper down and into furcations more effectively than through conventional scaling and, therefore, the need for periodontal surgery is greatly reduced.
We are even seeing spontaneous bony in-fill in infra-bony defects following non-surgical laser treatment (deep pocket therapy), so there is very little need for expensive and potentially painful regenerative surgery (as illustrated in the second case). Coupled with the advantages of less post-operative pain, less bleeding and so better visibility, and less if not permanent desensitisation, one would think lasers periodontics if the only way forward.
Of course, this same laser can be used to cut bone and, therefore, if surgery is indicated, a laser is a one-stop tool, able to raise the flap, remove the granulation tissue, remove the biofilm, re-contour the bone without heat damage and desensitize the root surface. Also, following surgery, we have certainly found far less post-operative pain than through conventional surgery.
The last advantage to perhaps mention is the ability to treat peri-implantitis with this laser, due to its ability to remove biofilm from the implant surface without damage to the implant surface or bone. Again, this can be carried out non-surgically with radial firing tips in many cases.