Laser-assisted new attachment procedure
Laser-assisted new attachment procedure (the LANAP protocol) is a surgical therapy designed for the treatment of periodontitis through regeneration rather than resection. This therapy and the laser used to perform it have been in use for more than a decade. Developed and refined in Cerritos, California, since 1991 by Dr. Robert H. Gregg II (http://abcnews.go.com/Video/playerIndex?id=4797206) and Dr. Delwin McCarthy to achieve consistently effective and predictable outcomes. The U.S. Food and Drug Administration cleared the LANAP protocol for the treatment of periodontitis, or gum disease, in 2004.
In LANAP surgery, a variable free-running pulsed neodymium:yttrium-aluminum-garnet (Nd:YAG at 1064 nm wavelength) dental laser is used by a trained and certified dentist or periodontist to treat the periodontal pocket. The laser energy selectively removes diseased or infected pocket epithelium from the underlying connective tissue. The necrotic epithelium is stripped from the connective tissue at the histologic level of the rete ridges. Since the laser energy is quite selective for diseased tissue, the underlying pleuropotential connective tissue is spared, thereby permitting healing and regeneration rather than formation of a pocket seal by long junctional epithelium.
In periodontics, the LANAP protocol is a process through which cementum-mediated periodontal ligament new attachment to the root surface in the absence of long junctional epithelium is achieved for the treatment of moderate to severe gum disease (including gingivitis and periodontal disease). Stimulation of existing stem cells permits the formation of new root surface coating (cementum) and new connective tissue (periodontal ligament) formation (collagen) on tooth roots. The procedure’s success has challenged the old paradigm of periodontal healing in the absence of guided tissue regeneration barriers (GTR) or bone grafting materials (allografts).
Early LANAP research showed consistent mean pocket depth reduction (50%) and improved bone density (48%) in an 8-year retrospective study of the protocol’s earliest clinical results. The Emago imaging system demonstrated that 100% of these cases showed some amount of bone density increases. The procedure has also proven effective at reducing pocket depth without gingival recession over a 6-month period.
Raymond A. Yukna (University of Colorado, formerly Louisiana State University) has provided histologic, statistical and radiographic evidence to demonstrate LANAP’s efficacy in pocket depth reduction via cementum-mediated new attachment. His in vivo split-mouth study comparing scaling and root planing to LANAP employed radiographic and histologic evidence derived from teeth harvested from treated patients en bloc. LANAP-treated teeth demonstrated universally cementum-mediated new attachment. Teeth treated with scaling and root planing evidenced only long junctional epithelium as the body of scientific evidence shows.
After the LANAP procedure, most patients experience new root surface coating (cementum) and new connective tissues (periodontal ligament) formation (collagen) on tooth roots, preventing tooth loss. Pocket depth reduction is comparable to that achieved by conventional resective osseous or pocket reduction surgery, but without the gingival recession normally associated with osseous surgery. Significant post-operative reduction in gingival indices, gingival inflammation, and bleeding on probing are also common desirable results of the LANAP protocol.
Because the LANAP protocol spares more healthy tissue than scaling and root planning or osseous surgery, patients experience minimal post-operative pain, bleeding, swelling, gum recession or root sensitivity. These results reduce the future risk of root caries/dental decay of the tooth root. Any discomfort is easily controlled through the use of non-steroidal anti-inflammatory drugs (over-the-counter NSAIDs) such as ibuprofen.
With regular three-month periodontal recall and maintenance, the LANAP-provided new attachment is stable and has proven resistant to future periodontal breakdown. Patients are encouraged to improve and maintain standards of oral hygiene to prevent further active periodontitis.
Drs. Gregg and McCarthy pioneered the use of the Nd:YAG laser to treat gum disease in the 1990s. Their success at regenerating bone growth and stimulating new attachment in their toughest patients encouraged them to perform further research and fine-tune the protocol that incorporates use of the PerioLase MPV-7 laser (Millennium Dental Technologies, Inc.)
Studies continue to uncover some startling consequences for poor gum health, which makes the creation of a palatable treatment an important tool in American health care. Widely reported studies have linked gum disease with heart disease and stroke. A recent case has now linked periodontitis with a full-term baby’s death. The mother’s untreated periodontitis is thought to have introduced deadly bacteria into her womb.
Although about 80% of Americans suffer from gum disease, about 97% of those with moderate to severe periodontitis are not being treated. Acceptance of the LANAP technique in gum disease treatment, introduces an option that more patients are willing to accept.
There are those who debate LANAP’s results. The American Academy of Periodontology (AAP) has yet to amend its August 1999 statement questioning the procedure, when it stated, “The Academy is not aware of any randomized blinded controlled longitudinal clinical trials, cohort or longitudinal studies, or case-controlled studies indicating that ‘laser excisional new attachment procedure (or Laser ENAP)’ or ‘laser curettage’ offers any advantageous clinical result not achieved by traditional periodontal therapy. Moreover, published studies suggest that use of lasers for ENAP procedures and/or gingival curettage could render root surfaces and adjacent alveolar bone incompatible with normal cell attachment and healing.”
At odds with AAP’s stance are subsequent peer-reviewed articles such as Yukna’s manuscript of human histology on 12 teeth published in the International Journal of Periodontics and Restorative Dentistry in December 2007 and the Harris article in General Dentistry in November 2004 which used a different laser. And according to the U.S. Food and Drug Administration, ENAP is not LANAP (see k030290 reference below).
Competitive procedures have been introduced to the field, but none have yet provided the science to support their results or continued use.
How the LANAP Protocol Works:
First, the patient is given local anesthetic. Next, the patient’s pocket depths are probed down to the level of intra-osseous defects (bone sounding). The thin optic fiber is placed parallel to the root surface. The first pass with the laser, called laser troughing, is accomplished with the short duration pulse. Perio pathogens and pathologic proteins are selectively destroyed by the laser’s light energy, providing a disinfected environment that allows healing following the laser hemostasis step.
The technique uses selective photothermolysis to remove the diseased, infected and inflamed pocket epithelium while preserving healthy connective tissue, literally separating the tissue layers at the level of the reté ridges. The practitioner is able to achieve both precise removal of deceased tissue and hemostasis by varying the laser’s energy density, pulse duration and rate of repetition. The laser assists in the destruction of perio pathogens while preserving the healthy tissue. The PerioLase MVP-7 is specifically designed to support the LANAP protocol for the treatment of moderate to severe gum disease, as well as other new treatment protocols and soft and hard tissue applications.
The tenacity of the calcified plaque and calculus adherent to the root surface is modified by the laser energy so its removal with an ultrasonic scaler is more easily accomplished.
At this point, a second pass with the laser is taken to finish debriding the pocket and achieve hemostasis with a thermal fibrin clot. Gingival tissue is compressed against the root surface as necessary to close the pocket and aid with formation and stabilization of the fibrin clot. No sutures, surgical glue or collagen plugs are needed. Mobile teeth above class II mobility are splinted. Occlusal adjustments are performed to remove interferences, minimize trauma, and provide balance to long axis forces and are considered an essential component of the LANAP protocol.
Finally, post-operative instructions specific to the LANAP protocol, diet guidelines and oral hygiene instructions are explained and their importance is stressed, and continued periodontal maintenance is scheduled. Patients are monitored at one week, 30 days and then every 3 months for periodontal maintenance. No subsequent probing is performed for at least nine months to a year to allow sufficient healing time for the cementum-fiber PDL interface.
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19. FDA Approval