The Er,Cr:YSGG (Erbium, Chromium: Yttrium, Scandium, Gallium Garnet) laser, wavelength 2790nm, is one of the newest wavelengths on the market. Consequently, there is not as much literature published about this wavelength compared to the others, and not as much inclusion in systematic reviews and meta-analyses. Having said that, the literature that has been published is mostly favorable for its use in the treatment of periodontal diseases, and actually more favorable than the findings with soft tissue lasers. It has a very similar wavelength to the Er:YAG (2940nm), and so the two are frequently grouped together as Erbium Lasers. There are very slight differences in terms of biological tissue interactions, but greater differences when it comes to the actual machines and their usability and delivery mechanisms. (see comparative table page).
This laser is an all-tissue laser – which means it can be used on both soft and hard tissues effectively, through a range of treatments, from gingival re-contouring to bone removal and root amputations. Its chromophores are water and hydroxyapatite. Due to its high absorption in water, its penetration depth through the soft tissues is very shallow (only 3um), which gives the user a great deal of control. However, at the same time, while there is some bio-modulation that inevitably occurs through the production of heat, these low level laser effects are not as profound as with the deeper penetrating wavelengths of diodes and Nd:YAGs.
Delivery of the laser energy is through a free running pulse (FRP) into a flexible fibre into a handpiece which makes for easy manipulation around the mouth. In most cases, tips are inserted into the handpiece (that essentially looks like a traditional turbine contra-angle handpiece used in dentistry). These tips can be end-firing – so laser energy comes from the end and is ideal to ‘cut’ tissues. However, one of the unique features about this laser is that they also have radial-firing tips, where 80% of the energy fires laterally, making them ideal to use in periodontal pockets, where the energy can work both on the root surface, and on the pocket lining.
It is the belief that the improved results and predictability through flapless treatment is partly due to these radial firing tips, where previously, sustained angulation of the tip would have made effective flapless treatment with access to all of the root surface much more difficult. However, to date, there is little literature published about the radial firing tips, and all in-vitro experiments and clinical trials have been carried out with end-firing ones.
Safety Considerations
As with all Class 4 lasers, there is a potential to damage the eyes, although the working distance of Er,Cr:YSGG is 5cm. However, despite this, of course the correct safety glasses should be worn by all in the operatory. This laser is used with a water spray which hydrates and cools the tissues, so if enough water is used and correct energy parameters, then the risk of burning soft tissues, causing bone necrosis, pulpal damage, root surface damage or implant surface damage is minimal. However, the main tissue interaction is a photo-thermal one, and if too little or no water is used, the laser is indeed very hot, and can of course then lead to bone necrosis or carbonization of the root surface, so it is essential, as with all lasers, to be trained in how to use the laser effectively and safely.
Clincal Case
Connective tissue graft for a 9mm recession defect; Er,Cr:YSGG used as part of a laser-assisted surgery protocol (Dr Rana Al-Falaki)
Periodontal pockets
It is an ideal laser to use in all aspects of periodontal therapy, both surgical and non-surgical. In the non-surgical management of periodontitis, is can be used in pockets where as well as having a bactericidal affect (mostly through photo-acoustic tissue interaction), it is also effective in the removal of biofilm, removal of root endotoxin, smear layer, calculus, granulation tissue, and infected pocket lining. It also modifies the root surface, which has been found to attract fibroblasts and blood components and be beneficial to healing. Removal of the outer epithelium is also part of the periodontal treatment protocol, to delay epithelial downgrowth and promote healing through a connective tissue attachment, as established with the CO2 animal studies. The radial firing tip also allows improved access into furcation areas via a flapless environment.
As part of a minimally invasive surgical protocol, this laser is also able to decorticate bone and modify the bone surface, stimulating the release of stem cells and growth factors, and stimulating regeneration. A protocol for this treatment modality has recently been refined in an effort to make it reproducible amongst clinicians, and been marketed as RePair (Regenerative erbium Periodontal Implant regime), although to date there are no clinical trials defining its success and no histological studies. However, several case reports show bone infill in infrabony defects when this laser has been used flaplessly.
In the more traditional form of periodontal surgery, this laser can be used to raise flaps, remove granulation tissue, remove calculus, modify or re-shape the root surfaces and furactions and remove or recontour bone, potentially making most other surgical instruments redundant. Having said that, ultrasonic scalers are probably more favorable to use for bulk calculus removal both in the flapped and flapless environment.
Radial Firing Periodontal tip
Soft and Hard tissue, and implant surgery
When it comes to all other types of soft tissue surgery, including gingivectomies, operculectomies, frenectomies, fibreotomies, vestibuloplasty, reserve vestibuloplasty, biopsies, removal of all soft tissue swellings, and thinning hyperplastic tissues, this laser is ideal, ‘cutting’ (ablating) tissue very well. The cut can be bloodless, but unlike diodes, Nd:YAGs and CO2 lasers, the haemostatic properties of this laser are not as effective, and so often there will be some bleeding from open wounds. This is particularly the case if a lot of water is used, as the tissues are cooled more. However, there is a haemostatic setting that can be used to stop bleeding of soft tissues, but this wouldn’t be the laser of choice to specifically stop heamorrhage or work on vascular lesions such as large haematomas. It can used in the treatment of oral ulceration and the desensitization of teeth, through a photo-thermal effect, sealing off the dentinal tubules. It is also effective in gingival depigmentation, through the surgical removal of the surface layer down to the melanocytes, rather than any particular affinity to pigment. In this same manner, it can be used to remove scarring and other forms of pigment such as amalgam tattoos.
In terms of bone surgery, this laser can be used for both soft and hard tissue crown lengthening, and so as well as gingival recontouring, is used to re-establish biological width. In certain cases and with suitable training, it can be used for flapless crown-lengthening. It can also be used to reduce bulky bone, remove tori, and in socket preservation and sinus-augmentation procedures prior to implant placement.
In grafting procedures, again, due to the versatility of tips and the fact that bleeding does occur, it can be used to both prepare the recipient bed (traditionally or through tunneling) and harvest the graft from the palate. It can also be used to de-epithelialise the papillae, remove smear layer, decontaminate and modify the root surface. A dual-wavelength approach is ideal, where a diode or Nd:YAG could then also be used to stop bleeding on palate and biostimulate to speed up healing of the palate and integration of the grafted tissue. It can also be used to remove composite restorations prior to grafting.
In implant dentistry, the Er,Cr:YSGG has been found to be effective and safe in the decontamination of the implant surface and removal of the titanium oxide layer without causing damage, needless to say, if the correct parameters are used. Temperature increase has been found to be minimal, so its use in the management of peri-implantitis is ideal, as of course it can also be used to de-granulate the area and is safe around bone. It is also used in atraumatic extractions, in sinus-augmentation and socket- preservation procedures, and has also been used in some cases for actual implant placement, although traditional methods are faster and probably more ideal at this point in time. It can of course be used to expose implants, but the risk of bleeding is greater than with diodes, so care with technique is needed here if planning to take an impression on the same day.
Clincal Case
Surgical depigmentation using YSGG in the lower arch (Walid Altayeb)
Practicalities
The speed of cut depends on the parameters used. No laser will be as fast as a scalpel blade, but the laser has far more advantages over a scalpel blade and generally isn’t used as a direct replacement. Speed of cut is considered good, and can be increased by manipulating parameters, but also at the same time risking potential damage to the tissues and their surrounding structures. Healing time is faster than most of the soft tissue laser wavelengths (a few days), although, again, it comes down to parameters used and if the tissues have been over-irradiated, then thermal damage will delay healing. The learning curve is fairly steep – the use of magnification greatly helps in the skill required to use Erbium lasers to their maximum efficiency, and as with all laser systems, it is essential to get adequate training for the system being used. The ease of using the machine itself is straightforward in that there are pre-sets for each procedure, and generally, they are perhaps a little safer to use for the novice. The price of the machine of course is generally higher than a diode and would be considered an expensive piece of equipment, but placed fairly reasonably for an all tissue laser in comparison to others. Running costs are generally low, with tip replacement being the main ongoing cost, and reliability has varied in the past, but has greatly improved in more recent years (commenting on Biolase system- Waterlase).
Patient acceptance is very good. In terms of billing, like with all the lasers discussed, the range of procedures offered in house tends to increase as well as the practitioners clinical repertoire, and so in this way, revenue often increases, alongside patient and operator satisfaction, enjoyment, and increase referrals.
A few final comments from our contributor, Rana Al-Falaki:
Can you comment on how you as a clinician have found the use of this laser wavelength to be an advantage to your clinical practice:
- Clinical procedures: The use of laser has not replaced what I do as a periodontist. However, it has improved my clinical results, and greatly reduced the need for flap surgery for periodontal pockets – in fact, I only did one in the last year, as I found the flapless procedures negated the need. The satisfaction of achieving such wonderful results for patients, and in such a short period of time, and with far less stress and difficulty negotiating the complex oral architecture certainly makes me an advocate for this wavelength.
- Time taken to carry out procedures- for periodontal pockets – this is longer, as I do everything I would have before, and then add the laser in as an extra step at the end. In terms of surgery for periodontal pockets or peri-implantitis – this generally takes less time and I use the laser for all steps, including removing granulation tissue, recontouring bone, and decontaminating the tooth or implant surface. Other surgical procedures such as frenectomies and other excision tend to take less time overall because you don’t then need time for suturing ad post-op tends to have fewer complications.
- The results obtained by incorporating lasers: patients tend to suffer mild discomfort after a surgical procedure leaving an open wound site such as a frenectomy. Generally, post- op complications are very few and all manageable with the use of mild analgesics if needed. The results obtained are extremely good – but like with everything, you have to know what you’re doing, what you’re trying to achieve, and have had adequate and effective training.
- Increased Practice revenue: I would say that perhaps this has the potential to increase by the fact you offer more treatment options and get more referrals from fellow dental practitioners, from existing patients and self-referrals.
Clincal Cases
Intrabony pocket treated with Radial firing tip flaplessly (one treatment) – R Al-Falaki
Infrabony defect treated with one session of scaling followed by laser with radial firing tip (R Al-Falaki)
Perio-endo lesion treated with root canal treatment followed by one session of scaling and laser using radial firing tip (R Al-Falaki)
Peri-implantitis treatment using Er,Cr:YSGG and end-firing tips (R Al-Falaki)
Flapless treatment of peri-implantitis using radial firing tip (R Al-Falaki)
Treatment of an abscess around an implant (R Al-Falaki)
Soft and hard tissue crown lengthening in the lower arch using Er,Cr:YSGG (R Al-Falaki)
Papilla-plasty : re-shaping of the papilla as part of a cosmetic crown lengthening case (Glen Van As)
Er,Cr:YSGG has been used in a tunneling procedure to manage gingival recession (Preety Desai)
End-firing tip being used to demonstrate the lasers’ ability to remove calculus from the root surface- note lower third of the root groove where calculus has been removed
Er,Cr:YSGG laser has been used in atraumatic extraction procedure and socket preservation, removing the granulation tissue from the walls and base of the pocket (Preety Desai)
Atraumatic extraction and socket preservation using Er,Cr:YSGG laser (Glen Van As)
Frenectomy using Er,Cr:YSGG before and after 3 months – note minimal scarring (R Al-Falaki)
Tunnel preparation for management of Class III furcation (R Al-Falaki)
Flapless restoration of biological width (R Al-Falaki)
Gingivectomy to expose subgingival cavity which can then be restored (R Al-Falaki)
Orthodontic exposure – note with certain settings, a bloodless cut is achievable (R Al-Falaki)
Tissue thinning for management of periodontal pockets (R Al-Falaki)
Crown Lengthening Using Er,Cr:YSGG laser – used to carryout gingivectomy, followed by flapless bone removal. Final photos are one year after surgery was carried out; 9 months after restoartions were placed. (Dr Rana Al-Falaki)