Effects of an Nd:YAP laser used for root canal disinfection in pulp regenerative therapy: a pilot study

This study aimed to compare the disinfection effects between a triple antibiotic paste and neodymium-doped yttrium aluminum perovskite (Nd:YAP) laser in pulp regenerative therapy and evaluate corresponding therapeutic effects based on apical radiographs and cone-beam computed tomography (CBCT). Sixty-six immature permanent teeth in 66 patients diagnosed with acute or chronic apical periodontitis were analyzed. All teeth were given pulp regenerative therapy. The patients were categorized into a control (triple antibiotic paste) and an experimental (Nd:YAP laser) group. Teeth in the experimental group were disinfected using an Nd:YAP laser, while those in the control group were disinfected using a triple antibiotic paste. Clinical and radiological examinations were performed every 3–6 months after treatment and followed up for 24 months. Statistical analysis was performed after clinical examination and showed that after one week of treatment, symptoms persisted in two teeth in the control group and two teeth in the experimental group. Two weeks later, the clinical symptoms disappeared in all teeth (p > 0.05). After 24 months of follow-up, the clinical symptoms recurred in two teeth in the control group and one tooth in the experimental group. On radiographic examination, 31 and 27 teeth showed continued root development, and three and two teeth showed no obvious root development in the control and experimental groups, respectively. The pulp sensibility test was positive in four teeth in both groups, with no significant difference between the two groups (p > 0.05). The results of this study suggest that endodontic irradiation with an Nd:YAP laser could be an effective alternative to triple antibiotic paste during disinfection of pulp regenerative therapy. Treatment outcomes were assessed using apical radiographs and CBCT, and no negative prognostic effects of the Nd:YAP laser on pulp regenerative therapy were found.

Immature permanent tooth; Nd:YAP laser; Pulp regenerative therapy; Triple antibiotic paste; Root canal disinfection

[1] Iwaya SI, Ikawa M, Kubota M. Revascularization of an immature permanent tooth with apical periodontitis and sinus tract. Dental Traumatology. 2010; 17: 185–187.

[2] Banchs F, Trope M. Revascularization of immature permanent teeth with apical periodontitis: new treatment protocol? Journal of Endodontics. 2004; 30: 196–200.

[3] American Association of Endodontists (AAE). Clinical considerations for a regenerative procedure. 2021. Available at: https: //www.aae.org/specialty/wp-content/uploads/sites/2/ 2021/08/ClinicalConsiderationsApprovedByREC062921.pdf (Accessed: 08 March 2022).

[4] Galler KM, Krastl G, Simon S, Van Gorp G, Meschi N, Vahedi B, et al. European Society of Endodontology position statement: revitalization procedures. International Endodontic Journal. 2016; 49: 717–723.

[5] Fouad AF. Contemporary microbial and antimicrobial considerations in regenerative endodontic therapy. Journal of Endodontics. 2020; 46: S105–S114.

[6] Gurbuz T, Ozdemir Y, Kara N, Zehir C, Kurudirek M. Evaluation of root canal dentin after Nd:YAG laser irradiation and treatment with five different irrigation solutions: a preliminary study. Journal of Endodontics. 2008; 34: 318–321.

[7] Franzen R, Esteves-Oliveira M, Meister J, Wallerang A, Vanweersch L, Lampert F, et al. Decontamination of deep dentin by means of erbium, chromium: yttrium-scandium-gallium-garnet laser irradiation. Lasers in Medical Science. 2009; 24: 75–80.

[8] Namour A, Geerts S, Zeinoun T, De Moor R, Nammour S. Safety irradiation parameters of Nd:YAP laser beam for endodontic treatments: an in vitro study. BioMed Research International. 2016; 2016: 1–5.

[9] Estrela C, Estrela CR, Decurcio DA, Hollanda AC, Silva JA. Antimicrobial efficacy of ozonated water, gaseous ozone, sodium hypochlorite and chlorhexidine in infected human root canals. International Endodontic Journal. 2007; 40: 85–93.

[10] Moshonov J, Peretz B, Brown T, Rotstein I. Cleaning of the root canal using Nd:YAP laser and its effect on the mineral content of the dentin. Journal of Clinical Laser Medicine Surgery. 2004; 22: 87–89.

[11] Gu Y, Perinpanayagam H, Kum DJ, Yoo YJ, Jeong JS, Lim SM, et al. Effect of different agitation techniques on the penetration of irrigant and sealer into dentinal tubules. Photomedicine & Laser Surgery. 2016; 35: 71–77.

[12] Ambrosini P, Miller N, Briançon S, Gallina S, Penaud J. Clinical and microbiological evaluation of the effectiveness of the Nd:Yap laser for the initial treatment of adult periodontitis. A randomized controlled study. Journal of Clinical Periodontology. 20105; 32: 670–676.

[13] Hoshino E, Kurihara-Ando N, Sato I, Uematsu H, Sato M, Kota K, et al. In-vitro antibacterial susceptibility of bacteria taken from infected root dentine to a mixture of ciprofloxacin, metronidazole and minocycline. International Endodontic Journal. 2010; 29: 125–130.

[14] Diogenes A, Ruparel NB, Shiloah Y, Hargreaves KM. Regenerative endodontics: a way forward. Journal of the American Dental Association. 2016; 147: 372–380.

[15] Kim SG, Malek M, Sigurdsson A, Lin LM, Kahler B. Regenerative endodontics: a comprehensive review. International Endodontic Journal. 2018; 51: 1367–1388.

[16] Hargreaves KM, Geisler T, Henry M, Wang Y. Regeneration potential of the young permanent tooth: what does the future hold? Journal of Endodontics. 2008; 34: S51–S56.

[17] Jung IY, Lee SJ, Hargreaves KM. Biologically based treatment of immature permanent teeth with pulpal necrosis: a case series. Journal of Endodontics. 2008; 34: 876–887.

[18] Petrino JA, Boda KK, Shambarger S, Bowles WR, McClanahan SB. Challenges in regenerative endodontics: a case series. Journal of Endodontics. 2010; 36: 536–541.

[19] Sato T, Hoshino E, Uematsu H, Noda T. In vitro antimicrobial susceptibility to combinations of drugs of bacteria from carious and endodontic lesions of human deciduous teeth. Oral Microbiology and Immunology. 1993; 8: 172–176.

[20] Sato I, Ando-Kurihara N, Kota K, Iwaku M, Hoshino E. Sterilization of infected root-canal dentine by topical application of a mixture of ciprofloxacin, metronidazole and minocycline in situ. International Endodontic Journal. 1996; 29: 118–124.

[21] Windley W 3rd, Teixeira F, Levin L, Sigurdsson A, Trope M. Disinfection of immature teeth with a triple antibiotic paste. Journal of Endodontics. 2005; 31: 439–443.

[22] Blum J, Michailesco P, Abadie MJM. An evaluation of the bactericidal effect of the Nd:YAP laser. Journal of Endodontics. 1997; 23: 583–585.

[23] Blum J, Abadie MJM. Study of the Nd:YAP laser. Effect on canal cleanliness. Journal of Endodontics. 1997; 23: 669–675.

[24] Aamour A, Nammour S, Peremans A, Heysselaer D, De Moor RJ. Treatment of dentinal hypersensitivity by means of Nd:YAP Laser: a preliminary in vitro study. The Scientific World Journal. 2014; 2014: 7.

[25] Farge P, Nahas P, Bonin P. In vitro study of a Nd:YAP Laser in endodontic retreatment. Journal of Endodontics. 1998; 24: 359–363.

[26] Liu T, Huang Z, Ju Y, Tang X. Bactericidal efficacy of three parameters of Nd:YAP laser irradiation against Enterococcus faecalis compared with NaOCl irrigation. Lasers in Medical Science. 2018; 34: 359–366.

[27] He H, Yu J, Song Y, Lu S, Liu H, Liu L. Thermal and morphological effects of the pulsed Nd:YAG laser on root canal surfaces. Photomedicine & Laser Surgery. 2009; 27: 235–240.

[28] Kahler B, Rossi-Fedele G, Chugal N, Lin LM. An Evidence-based review of the efficacy of treatment approaches for immature permanent teeth with pulp necrosis. Journal of Endodontics. 2017; 43: 1052–1057.

[29] Tong HJ, Rajan S, Bhujel N, Kang J, Duggal M, Nazzal H. Regenerative endodontic therapy in the management of nonvital immature permanent teeth: a systematic review-outcome evaluation and meta-analysis. Journal of Endodontics. 2017; 43: 1453–1464.

[30] Torabinejad M, Nosrat A, Verma P, Udochukwu O. Regenerative endodontic treatment or mineral trioxide aggregate apical plug in teeth with necrotic pulps and open apices: a systematic review and meta-analysis. Journal of Endodontics. 2017; 43: 1806–1820.

[31] Chen YP, Jovani-Sancho Mdel M, Sheth CC. Is revascularization of immature permanent teeth an effective and reproducible technique?Dental Traumatology. 2015; 31: 429–436.

[32] Lin J, Zeng Q, Wei X, Zhao W, Cui M, Gu J, et al. Regenerative endodontics versus apexification in immature permanent teeth with apical periodontitis: a prospective randomized controlled study. Journal of Endodontics. 2017; 43: 1821–1827.

[33] Li L, Pan Y, Mei L, Li J. Clinical and radiographic outcomes in immature permanent necrotic evaginated teeth treated with regenerative endodontic procedures. Journal of Endodontics. 2017; 43: 246–251.

[34] Chan EKM, Desmeules M, Cielecki M, Dabbagh B, Ferraz dos Santos B. Longitudinal cohort study of regenerative endodontic treatment for immature necrotic permanent teeth. Journal of Endodontics. 2017; 43: 395–400.

[35] Nazzal H, Ainscough S, Kang J, Duggal MS. Revitalisation endodontic treatment of traumatised immature teeth: a prospective long-term clinical study. European Archives of Paediatric Dentistry. 2020; 21: 587–596.

[36] Huang GT, Lin LM. Letter to the editor: comments on the use of the term “revascularization” to describe root regeneration. Journal of Endodontics. 2008; 34: 511.

[37] Linsuwanont P, Sinpitaksakul P, Lertsakchai T. Evaluation of root maturation after revitalization in immature permanent teeth with nonvital pulps by cone beam computed tomography and conventional radiographs. International Endodontic Journal. 2017; 50: 836–846.