Successful endodontic treatment depends upon maximal debridement and disinfection of the entire root canal system. The root canal system must be shaped to a convenience form that permits adequate cleaning and disinfection by elimination of microbes.1 The literature is clear that as much as 35 percent or more of the root canal system remains untouched by any instrumentation technique. Essentially no filing technique allows instruments to sculpt all canal walls and remove infected dentin.2 To decrease the bacterial load and achieve better debridement, irrigation protocols are used prior to obturation. The efficacy of the irrigants to decontaminate canal walls has seen significant improvements recently. Both negative and positive apical pressure irrigation techniques have been surpassed by ultrasonically activated irrigants, photo-activated disinfection and laser-activated irrigants in their ability to improve cleanliness of the canal system.3,4
In particular, the Er:YAG (Lightwalker Er:YAG& Nd:YAG Dental laser, National Dental Inc,Barrie, ON) laser has shown to be effective at removing debris and the smear layer from canal walls.3,4 A final application of the Er:YAG laser with EDTA after standardized instrumentation can result in improved cleaning of the canal walls with a higher quantity of open tubules (Fig. 1) in comparison to results without the use of the laser.3,4
A new application of Laser-Activated Irrigation (LAI) has been recently introduced. Photon Induced Photoacoustic Streaming (PIPS™) uses an Erbium 2,940 laser to pulse extremely low energy levels of laser light to generate a photoacoustic shockwave, which streams irrigants throughout the entire root canal system.8 Using extremely short bursts of peak power, laser energy is directed down into the canal and the action actively pumps the tissue debris out of the canals while cleaning, disinfecting and sterilizing each main canal, lateral canals, dentinal tubules and canal anastomoses to the apex. This movement of irrigant is achieved without the need to place the radial and stripped laser tip (PIPS™ tip) (Fig. 2) into the canal itself, as with other conventional hand and ultrasonic systems. The tip is held stationary in the coronal aspect of the access preparation only. With the irrigant occupying the entire root canal system, the shock wave created by PIPS™ travels in all directions during activation and effectively debrides and removes organic tissue remnants.9 Through this laser-activated turbulent flow phenomenon, clinicians following the PIPS™ protocol are not required to place the tip into each canal, thus eliminating the need to enlarge and remove more tooth structure to deliver standard needle irrigation to the smaller and more delicate apical anatomy, commonly seen in the apical one third. The results are canal convenience forms that are more conservative, minimally invasive and biomimetic preventing the unnecessary removal of tooth structure (Fig. 3).
Unlike other laser-activated irrigant techniques, PIPS™ is not a thermal event, rather subablative. Properly executed, PIPS™ creates turbulent photoacoustic agitation of irrigants that move fluids three dimensionally throughout the root canal system even as far as the apical terminus, distant from the radial stripped tip location. By activating the tip in the access cavity and outside the root canal system, the extremely low energy needed to activate the unique PIPS™ tip (20 mJs or less) is below the threshold of ablation for dentin.5,6 Ledging and thermal effects that have plagued the widespread use of other laser systems is completely avoided at the energy levels used by the PIPS™ technique.
Recent testing, performed at the University of Tennessee by Dr. Adam Lloyd, Chairman of the Department for Endodontics, objectively confirmed the improved cleaning and debridement of organic and inorganic tissue left by instrumentation. Micro-computed tomography scans were used to assess before and after volumetric change in the internal intaglio of lower first molars treated with PIPS™ protocol (Fig. 4). Sequential slicing beginning at 6 mm from the apex and moving down to the last 2 mm demonstrated that all slice images showed significant improvements after PIPS™. The importance of these findings is far reaching. PIPS™ now offers the dentist a less technique sensitive, minimally invasive and time reducing method for irrigating and preparing endodontic root canal systems. Because PIPS™ has demonstrated its ability to decontaminate and debride areas that files and instrumentation cannot reach, success rates rise and retreatment for past failures is possible.7 PIPS™ is also helpful in locating and helping negotiate calcified canals. PIPS™ is a valuable additional tool in the treatment of endodontics regardless of the shaping and obturation system used by the dentist.
Laser technology used in endodontics during the last 20 years has undergone an important evolution. Research in recent years has been directed toward producing laser technologies (such as impulses of reduced length, radial-firing and stripped tips) and techniques (such as LAI and PIPS) that are able to simplify laser use in endodontics and minimize the undesirable thermal effects on the dentinal walls, using lower energies in the presence of chemical irrigants. EDTA has proved to be the best solution for the LAI technique that activates the liquid and enhances cleaning of the smear layer. The use of a laser (PIPS) to activate sodium hypochlorite increases its antimicrobial activity. Finally, using the correct protocol the PIPS technique reduces the thermal effects and exerts both a stronger cleaning and bactericidal action, because of its streaming of fluids initiated by the photonic energy of the laser. Studies are currently underway to further validate LAI and PIPS technique as innovative technologies in modern endodontics.
PIPS ENDO/PERIO CASE STUDY
A patient asked for the option to save her teeth that were scheduled for extraction by another dentist. The lower left first and second molars had high mobility (grade 2) were necrotic, with significant probing depths in the buccal aspect. The teeth were diagnosed for endo–perio treatment. Difficulties with this case included complex radicular anatomy, long anatomical measurements (26 and 27 mm respectively for #36 and #37) and the presence of a deep vertical bone loss in the buccal aspect. After scaling and root planning, the teeth were scheduled for root–canal therapy. Before each treatment the PIPS™ technique was applied into the periodontal pockets of each tooth for refining the debridement, removal of biofilm from the root surfaces and pocket disinfection. The root–canal treatments were performed using PIPS™– specific irrigation protocols with 5% NaOCl and 17% EDTA. The canals were obturated with a flowable resin sealer (Endoreze Ultradent, South Jordan, UT–USA) and gutta–percha points. A final treatment of the pockets using PIPS™ for disinfection was performed after completing each root canal therapy to remove any extruded sealer or residual biofilm. No post–op symptoms were reported and the mobility of the teeth progressively disappeared up to grade 0. The follow up X–rays performed after one and four months showed healing in progress for both the teeth. LightWalker AT laser device with contact H14–C handpiece and PIPS™ fiber tip was used for the treatment.
No post–op symptoms were reported and the mobility of the teeth progressively disappeared up to grade 0.OH
Laser source: Er:YAG
Wavelength: 2940 nm
Pulse duration: SSP, 50µsec
Energy: 15 mJ
Frequency: 15 Hz
Dr. Enrico DiVito is a graduate of the University of the Pacific, Arthur A. Dugoni School of Dentistry. He is founder of the Arizona Center for Laser Dent
istry in Scottsdale where he maintains a full time practice with his son Dr. Rob DiVito. Dr. DiVito is also a professor at the Arizona School of Dentistry and Oral Health and is responsible for helping create the Department of Laser Dentistry. He is the inventor of PIPS laser activated irrigation and lectures both nationally and internationally and has published numerous articles in various major impact dental journals. He greatly enjoys being a practitioner, educator and innovator for dentistry. Dr DiVito can be reached at email@example.com or pipsdocs.com.
Dr. Giovanni Olivi is an Adjunct Professor of Endodontics at the University of Genoa School of Dentistry, and a Board member and Professor in the Master Course in Laser Dentistry at the same University. In 2002 he completed the postgraduate laser course at the University of Firenze, and two years later received laser certification from the International Society for Lasers in Dentistry (ISLD). In 2006 he achieved Advanced Proficiency from the Academy of Laser Dentistry (ALD) and received Mastership in 2009. Dr. Olivi is the 2007 recipient of ALD’s Leon Goldman Award for Clinical Excellence. He has authored more than 50 articles on dentistry topics and is a co-author of the books I Laser in Traumatologia Dentale (in Italian, Martina Publishing, Bologna, Italy, 2010) and Pediatric Laser Dentistry: A User’s Guide (in English, Quintessence Publishing, Chicago, Ill., USA, 2011). Dr. Olivi maintains a private practice in endodontics, restorative, and pediatric dentistry in Rome, Italy. Dr. Olivi may be contacted by e-mail at firstname.lastname@example.org.
Disclosure: Dr. Olivi has relationships with several laser companies (including Dentsply, Biolase, and Fotona) but received no financial compensation related to this article.
1. Clark D, Khademi JA. Case studies in modern molar endodontic access and directed dentin conservation, DentClin NorthAm. 2010:54:275-289
2. Peters OA, Schonenberger K, Laib A. Effects of four Ni-Ti preparation techniques on root canal geometry assessed by micro-computed tomography, International Endodontic Journal
3. George R, Meyers IW, Walsh LJ (2008) Laser activation of endodontic irrigants with improved conical laser fiber tips for removing smear layer in the apical third of the root canal, J Endod 34:1524–15274.
4. de Groot SD, Verhaagen B, Versluis M, Wu MK, Wesselink PR, van der Sluis LW (2009) Laser-activated irrigation within root canals: cleaning efficacy and flow visualization International Endodontic Journal 42:1077-1083
5. Li Z., Code JE., Van De Merwe WP. Er:YAG Er:YAG Laser ablation of enamel and dentin of human teeth: determination of the ablation rates at various fluences and pulse repetition rates. Lasers in Surgery and Medicine. 1992, 12:625-630.
6. Majaron B, Lukac M, Sustercic D, et al. Threshold and efficiency analysis in Er:YAG laser ablation of hard dental tissue. Proc SPIE. 1996;2922:233-242.
7. DiVito, E., O.A. Peters, and G. Olivi, Effectiveness of the erbium:YAG laser and new design radial and stripped tips in removing the smear layer after root canal instrumentation. Lasers Med Sci, 2012. 27(2): p. 273-80
8. R. Ordinal-Zapata, C.M. Bramante, R.M. Aprecio, R. Handysides, D. E. Jaramillo, Biofilm removal by 6% sodium hypochlorite activated by different irrigation techniques. International Endodontic Journal, 2013
9. Lloyd A, Uhles JP, Clement DJ, Garcia-Godoy F. Elimination of intracanal tissue and debris through a novel laser-activated system assessed using high resolution micro-computed tomography. J Endod 2013; in press.