Lasers in non-surgical periodontal treatment – a review

Far-ultraviolet irradiation at 222 nm destroys and sterilizes the biofilms formed by periodontitis pathogens

BACKGROUND

Periodontal disease is the leading cause of tooth loss, and an association between periodontal disease and non-oral systemic diseases has been shown. Formation of biofilm by periodontal pathogens such as Fusobacterium nucleatum, Porphyromonas gingivalis, and Streptococcus mutans and their resistance to antimicrobial agents are at the root of persistent and chronic bacterial infections.

METHODS

The bactericidal effect of far-ultraviolet (F-UV) light irradiation at 222 nm on periodontal bacteria was assessed qualitatively and quantitatively. The effect of biofilm disruption by F-UV light on periodontal bacteria was examined by crystal violet staining, and the morphologic changes of the biofilm after F-UV irradiation were explored by confocal laser microscopy and scanning electron microscopy. We developed a thin fiber-type 222 nm F-UV irradiator and studied its safety and effect of reducing bacteria in rodent models.

RESULTS

F-UV light at 222 nm had a bactericidal effect on F. nucleatum, P. gingivalis, and S. mutans. Irradiation with F-UV light reduced the biofilm formed by the bacteria and sterilized them from within. Confocal laser microscopy showed a clear reduction in biofilm thickness, and scanning electron microscopy confirmed disintegration of the biofilm architecture. F-UV irradiation was less damaging to DNA and less cytotoxic than deep-ultraviolet light, and it reduced bacterial counts on the tooth surface.

CONCLUSION

F-UV irradiation has the potential to destroy biofilm and act as a bactericide against pathogenic bacteria in the biofilm.

Clinical efficacy and pain control of diode laser-assisted flap surgery in the treatment of chronic periodontitis:A systematic review and meta-analysis

Objective

To assess the diode laser-assisted periodontal flap surgery's clinical effectiveness and postoperative pain management in treating chronic periodontitis, and to offer evidence-based medical justification for the procedure's clinical use.

Data sources and study selection

In this study, a computer combined with manual search was used to search for articles on diode laser-assisted periodontal flap surgery for the treatment of chronic periodontitis published from the establishment of the database to September 2023. The databases searched included China Academic Journal Full Text Database (CNKI), China Biomedical Literature Database (CBM), Chinese Science and Technology Journal Database (VIP), Wanfang Database, PubMed, Web of science, Cochrane Library, Embase, and Scopus. Two researchers independently performed the screening and study selection, following the inclusion and exclusion standards to extract basic information and required data. Meta-analysis of the included literature was performed using Revman V5.4 software.

Result

Thirteen articles were analyzed. Meta-analysis showed that the use of the diode laser was effective in reducing patients' probing pocket depth (PPD) at 3 and 6 months postoperatively (3 months: MD = -0.46, 95 % CI = [-0.89, -0.03], P = 0.04; 6 months: MD = -0.35, 95 % CI = [-0.63, -0.06], P = 0.02), was able to effectively improve 3 month clinical attachment level (CAL) (MD = -0.36, 95 % CI = [-0.66, -0.06], P = 0.02), and was able to promote wound healing and reduce patients' early postoperative pain (MD = 0.67, 95 % CI = [0.01, 1.32], P = 0.05; MD = -1.67, 95 % CI = [-2.23, -1.00], and P < 0. 001), while for gingival index (GI), the use of diode laser did not have a significant effect.

Conclusions

The available evidence suggests that the use of a diode laser adjunct is effective in reducing PPD, improving CAL, promoting wound healing, and reducing early postoperative pain in patients compared with flap application alone; however, for GI, diode lasers did not show any improvements.

Clinical significance

Periodontal flap surgery fails to eliminate microorganisms from the soft tissue wall, potentially leading to recolonization, reinfection, and accompanying side effects such as pain and swelling. The use of a diode laser reduces PPD, improves CAL, and relieves early postoperative pain.

Efficacy of two diode lasers in the removal of calculus from the root surface: An in vitro study

INTRODUCTION

Scaling and root planning (SRP) is still the gold standard of nonsurgical periodontal therapy, and it has been accompanied by several supportive therapies in recent years. One of the most studied methods is the diode laser, thanks to its thermal and bactericidal properties. Our trial intended to verify whether it could influence the chemical bond between calculus and the root surface.

OBJECTIVES

The aim of the study was to assess the efficacy of the diode laser prior the mechanical removal of calculus in an in vitro application. The reduction in time and the number of strokes required to clean the untreated root surfaces were evaluated as primary outcomes. The pressure was considered as a secondary outcome.

METHODS

A total of 75 extracted human teeth with subgingival calculus were assigned equally among three treatment groups (n = 25) according to the size of the occupied areas, which were classified by evaluating the pixel numbers. The groups were assigned to either no pretreatment application (A), Laser Diode Fox III (Sweden & Martina) (B) or Wiser Laser Evolution (Doctor Smile) (C). The weight for instrumentation was calibrated for an After Five curette (Hu-Friedy, Chicago). A new set of tools was used for each group, and the curettes were sharpened after each use with the Sidekick sharpener (Hu-Friedy, Chicago).

RESULTS

A Kruskal-Wallis test was used to assess the significance for each considered parameter. The results were statistically significant for each parameter for the two groups where the laser was used compared to the control group.

CONCLUSIONS

Despite the limitations of an in vitro study, data showed that the diode laser had an overall positive effect on root debridement, facilitating SRP in terms of stroke count, time, and pressure.

Effect of an low-energy Nd: YAG laser on periodontal ligament stem cell homing through the SDF-1/CXCR4 signaling pathway

BACKGROUND

The key to the success of endogenous regeneration is to improve the homing rate of stem cells, and low-energy laser is an effective auxiliary means to promote cell migration and proliferation. The purpose of this study was to observe whether low-energy neodymium (Nd: YAG) laser with appropriate parameters can affect the proliferation and migration of periodontal ligament stem cells (PDLSCs) through SDF-1/CXCR4 pathway.

METHODS

h PDLSCs were cultured and identified. CCK8 assay was used to detect the proliferation of h PDLSCs after different power (0, 0.25, 0.5, 1, and 1.5 W) Nd: YAG laser (MSP, 10 Hz, 30 s, 300 μ m) irradiation at 2th, 3rd,5th, and 7th days, and the optimal laser irradiation parameters were selected for subsequent experiments. Then, the cells were categorized into five groups: control group (C), SDF-1 group (S), AMD3100 group (A), Nd: YAG laser irradiation group (N), and Nd: YAG laser irradiation + AMD3100 group (N + A). the migration of h PDLSCs was observed using Transwell, and the SDF-1 expression was evaluated using ELISA andRT-PCR. The SPSS Statistics 21.0 software was used for statistical analysis.

RESULTS

The fibroblasts cultured were identified as h PDLSCs. Compared with the C, when the power was 1 W, the proliferation rate of h PDLSCs was accelerated (P < 0.05). When the power was 1.5 W, the proliferation rate decreased (P < 0.05). When the power was 0.25 and 0.5 W, no statistically significant difference in the proliferation rate was observed (P > 0.05). The number of cell perforations values as follows: C (956.5 ± 51.74), A (981.5 ± 21.15), S (1253 ± 87.21), N (1336 ± 48.54), and N + A (1044 ± 22.13), that increased significantly in group N (P < 0.05), but decreased in group N + A (P < 0.05). The level of SDF-1 and the expression level of SDF-1 mRNA in groups N and N + A was higher than that in group C (P < 0.05) but lower than that in group A (P < 0.05).

CONCLUSIONS

Nd: YAG laser irradiation with appropriate parameters provides a new method for endogenous regeneration of periodontal tissue. SDF-1/CXCR4 signaling pathway may be the mechanism of LLLT promoting periodontal regeneration.

Recent development of photoacoustic imaging in dentistry: A review on studies over the last decade

Background

This work performs a literature review of photoacoustic imaging (PAI) in dentistry and discusses the development of PAI in relation to oral health.

Methods

A search method was used to locate papers published between 2011 and 2023 in Google Scholar and PubMed databases, and 25 studies were selected. Reports on PAI in dentistry were included. Articles not written in English or whose full text could not be accessed were excluded. The remaining publications were checked and evaluated to determine whether they contain supportive materials for PAI in dentistry.

Results

The majority of articles about PAI in dentistry are associated with caries studies. Photoacoustic microscopy is the most commonly utilized PAI system. PAI studies generally focus on ex-vivo investigations using extracted human teeth. The acoustic signal obtained from carious teeth is greater than that obtained from normal teeth. In addition to imaging oral soft tissues from animal models and the periodontal pocket depth in human volunteers, PAI is applied to evaluate dental implants and oral biofilms.

Conclusion

There have been numerous investigation on PAI in dentistry, but it is not yet applicable in dental practice. In the future, PAI studies are expected to contribute to the invention of an alternative non-ionizing imaging technology that is comfortable for patients, user friendly, and capable of providing reliable information at a reasonable cost.

Causes of Emergency Bleeding after Nonsurgical Periodontal Therapy in Adult Periodontitis Patients: A Retrospective Analysis

Background

Emergency gingival uncontrollable bleeding after nonsurgical periodontal therapy (NSPT) could be caused by a variety of factors; local oral factors are the main cause of gingival bleeding in most patients. Because the doctor will do a good job of evaluating the patient's physical condition before nonsurgical periodontal therapy. This study is subjected to evaluate the possible factors associated with emergency uncontrollable bleeding within 24-48 hours after NSPT. Material and Methods. A total of fifty-eight patients with emergency bleeding after NSPT in the past four years were enrolled. The related factors in patients, such as age, gender, clotting function, systemic diseases, and baseline periodontitis severity, were analyzed. The site-related factors, such as tooth type, tooth distribution, and alveolar bone resorption at the bleeding site, were compared. The possible relationship of the parameters to the causes of emergency bleeding with NSPT was also evaluated.

Results

Gingival bleeding after NSPT was registered. In this retrospective study, a total of 58 patients were selected. There were 29 males and 29 females, aged from 20 to 67 years old, with an average age of 35.21 ± 10.09 years. Among them, 8.6% were over 50 years old, and 91.4% were under 50 years old. Completed evaluations were performed in 15.5% gingivitis and 84.5% periodontitis. The causes of emergency bleeding after nonsurgical periodontal therapy in this study were residual subgingival calculus or granulation tissue in 63.79% of cases: severe gingival inflammation, 29.32%; gum trauma, 3.45%; and poor compliance, 3.45%. The therapy method before bleeding includes supragingival scaling accounted for 72.4% and subgingival scaling accounted for 27.6%. 23 cases of horizontal absorption at the bleeding site accounted for 39.66%, and 35 cases of angular absorption accounted for 60.34%. Bleeding of maxillary posterior teeth accounted for 34.48%; mandibular anterior teeth accounted for 15.52%; mandibular anterior teeth accounted for 8.62%; and mandibular posterior teeth accounted for 18.97%; multiple sites accounted for 22.41%; eliminating residual subgingival calculus and granulation tissue were the main and most effective hemostatic methods, 86.21%.

Conclusion

Residual subgingival calculus or granulation tissue and severe gingival inflammation were the main causes of emergency gingival bleeding after nonsurgical periodontal therapy. Severe gingival inflammation causing emergency bleeding was more common in maxillary posterior teeth areas. Angular alveolar bone resorption was more likely to cause bleeding than horizontal resorption. Careful debridement of residual subgingival calculus and granulation tissue was the main hemostatic method.

Effect of Twinlight Laser on the Attachment of Human Gingival Fibroblasts to the Root Surface In Vitro

Background

This study aimed to compare the effectiveness of subgingival scaling and root planing with the Twinlight laser, Er: YAG laser, and hand instrumentation on the removal of endotoxin and attachment of human gingival fibroblasts (HGFs) to cementum surfaces in vitro.

Material/Methods

Single-rooted teeth extracted for periodontal disease were collected and divided into 3 groups: group A, root planing with Gracey curet no. 5/6; group B, irradiation with Er: YAG laser; group C, irradiation with Er: YAG laser and Nd: YAG laser. Endotoxins were determined by the limulus amebocyte lysate test. Cell attachment and proliferation of HGFs on root specimens were evaluated by cell counting kit-8 assay. The root surface and cell morphology were observed by scanning electron microscope.

Results

A flat root surface with scratches was found in group A, Group B had a homogeneous rough morphology without carbonization, and group C had a non-homogeneous rough morphology with ablation. The endotoxin concentration was highest in group A (P<0.05) and lowest in group C (P>0.05). HGFs cultured in group B showed significantly increased adhesion and proliferation compared with groups A and C (P<0.05). HGFs in group B were well attached, covered densely by pseudopodia. HGFs in group A were round with poor extension and short pseudopodia, while the cells in the group C were in narrow, triangular, or polygonal shapes.

Conclusions

Twinlight laser-assisted periodontal treatment effectively improved the biocompatibility of root surface and promoted the attachment and proliferation of fibroblasts by removing calculus and reducing the concentration of endotoxins.

Evaluation of GCF IL-17, IL-10, TWEAK and sclerostin levels after SRP and adjunctive use of diode laser application in periodontitis patients

BACKGROUND

The aim of the present study was to evaluate the clinical efficacy of the diode laser as an adjunct to scaling and root planing (SRP) and also determine the biochemical profile by evaluating the gingival crevicular fluid (GCF) levels of interleukin (IL)-17, IL-10, TNF-related weak inducer of apoptosis (TWEAK) and sclerostin.

METHODS

A total of 40 systemically healthy, stage III periodontitis patients were included in this randomized controlled study. Participants were randomly divided into two groups as scaling root planning (SRP) + diode laser(L) (0.80W power, 940nm wavelength and 0.80J/s energy level) and only SRP group. Recording of periodontal parameters and collecting GCF samples were performed at baseline, 1^st and 3^rd months. Biomarker levels in GCF were measured with ELISA .

RESULTS

At baseline, no significant difference was detected between groups in terms of both clinical and biochemical parameters. All biochemical parameters (except for IL-10 in control group), presented a statistically significant difference for 3 months study period in both groups. When laser and control groups were compared, significant differences were not observed, except the lower GCF IL-17 levels (p = 0.025), bleeding on probing (p = 0.028) and clinical attachment level (CAL) (p = 0.0002) values in laser group at 3^rd , 1^st and 3^rd months, respectively. Statistically significant correlations were also noted between biochemical parameters and clinical parameters.

CONCLUSION

The GCF IL-17, TWEAK and sclerostin levels may be useful for monitoring response to SRP+L therapy. However, long-term studies on higher populations are needed to evaluate the effectiveness of adjunctive use of diode laser application to SRP. This article is protected by copyright. All rights reserved.

Adjunctive Er:YAG laser in non-surgical periodontal therapy of patients with inadequately controlled type 2 diabetes mellitus: A split-mouth randomized controlled study

BACKGROUND AND OBJECTIVE

Limited studies are available comparing the outcomes of non-surgical periodontal therapy (NSPT) with or without adjunctive Er:YAG laser (ERL) in patients with type 2 diabetes mellitus (T2DM). This study evaluated the effects of ERL adjunctive NSPT on single-rooted teeth of inadequately controlled T2DM patients with periodontitis.

METHODS

Twenty-two inadequately controlled T2DM participants with periodontitis were recruited. Adopting a double-blinded split-mouth design and under block randomization, we investigated the effects of ERL in calculus removal then degranulation mode, or a sham treatment, adjunct NSPT, which included two visits of full-mouth root surface debridement delivered within 4-10 days, to test or control single-rooted teeth (Wuxi Stomatology Hospital, trial 2017-016). We followed periodontal parameters (plaque %, bleeding on probing [BOP] %, probing pocket depth [PPD], probing attachment level [PAL]) and selected systemic parameters (fasting plasma glucose [FPG], glycosylated hemoglobin [HbA1c%], high sensitivity C-reactive protein) at baseline, one, three, and six months after periodontal treatment.

RESULTS

The study was completed as planned. Periodontal parameters, FPG and HbA1c% of the 22 participants appeared significantly improved at six months (p < 0.001). The 44 ERL treated, compared to 44 sham treated single-rooted teeth exhibited significant improvement in BOP, mean PPD, and mean PAL at various postoperative follow-up time points (effect size ≥0.44; p < 0.001). No adverse event was reported.

CONCLUSION

Periodontal treatment outcomes in the T2DM patients with inadequate glycemic control were better in the single-rooted teeth received ERL adjunct NSPT. Further studies are warranted to confirm the observations reported in this short-term clinical study.

Effect of Various Laser-Activated Irrigation Protocols on Endodontic Sealer Penetration into the Dentinal Tubules: A Confocal Laser Scanning Microscopy Study

Objective: To study the effect of various laser-activated irrigation protocols on endodontic sealer penetration into the dentinal tubules. Background data: Laser-activated irrigation is helpful for smear layer removal and thus might increase the penetration of endodontic sealer into the dentinal tubules. Methods: Forty-eight mandibular premolars with straight canals were instrumented and divided into four groups: C-I group, conventional needle irrigation with sodium hypochlorite (NaOCl) followed by ethylenediaminetetraacetic acid (EDTA); Er:YAG-I, Er,Cr:YSGG-I, and Nd:YAP-I groups, NaOCl and EDTA irrigations activated by erbium:yttrium-aluminum-garnet (Er:YAG), erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG), and neodymium:yttrium-aluminum-perovskite (Nd:YAP) lasers, respectively. The cleanness of the treated canals was evaluated by scanning electron microscopy (SEM). Then, canals were obturated with AH-Plus sealer labeled with rhodamine B (0.1%) and combined with gutta-percha. After setting, canals were sectioned at 2, 5, and 8 mm short from the root apex, and the penetration area of the AH-Plus into the dentinal tubules was observed using confocal laser scanning microscopy (CLSM). Results: SEM results indicated that the Er:YAG-I and Er,Cr:YSGG-I lasers were more effective than the Nd:YAP-I and C-I in removing the smear layer. CLSM results indicated that the average AH-Plus penetration areas among the tested groups were in ascending order: C-I < Nd:YAP-I < Er:YAG-I, Er,Cr:YSGG-I (p < 0.05). Conclusions: Laser-activated irrigations significantly increased the penetration of the endodontic sealer into the dentinal tubules, among which Er:YAG-I and Er,Cr:YSGG-I lasers were the most effective and may be considered routine protocols for endodontic treatment.

Therapeutic effects of diode laser on vascular epulis in esthetic area

Vascular epulis is a rare clinical disease. In our study, a case of vascular epulis in the cosmetic area was treated by diode laser, without recurrence and obvious inflammation in the surgical site 5 years after surgery. This case report indicates that the excision of vascular epulis in the cosmetic area of the anterior teeth by diode laser could be an alternatively safe and complementary approach in lieu of conventional surgery.

In vivo investigation of diode laser application on red complex bacteria in non-surgical periodontal therapy: a split-mouth randomised control trial

Assessment of the efficacy of a single 810 nm diode laser application as an adjunctive treatment modality during the first intervention of non-surgical periodontal therapy (NPT). 25 patients diagnosed with chronic periodontitis underwent a split-mouth randomised control trial. The periodontal pockets of the test quadrants were treated with an 810 nm diode laser as an adjunct to NPT (Picasso GaAlAs; AMD Lasers). The laser was set at 1.0 W continuous wave, 400 µm tip, 796 W/cm² peak power density and a 32 J/cm² energy density. Therapeutic outcomes were evaluated based on the clinical parameters, which included probing pocket depth, recession, clinical attachment level, full mouth plaque score, full mouth bleeding on probing and tooth mobility. The baseline bacterial collection was completed from the periodontal pockets and then re-evaluated at 6 weeks. Clinical parameters demonstrated no statistical difference, with the exception of a statistically significant (P < 0.05) reduction in bleeding on probing for the test side. The test side resulted in a statistical increase of Capnocytophagaspecies and Treponemadenticola. The single application of the diode laser did not significantly improve the bacterial nor the clinical parameters in patients with chronic periodontitis.

Trial registration number: PACTR201909915338276.

Do Lasers Have an Adjunctive Role in Initial Non-Surgical Periodontal Therapy? A Systematic Review

(1) Background: dental lasers have numerous applications for periodontal therapy which include surgical procedures of soft tissue and osseous structures, and non-surgical treatments such as pathogen reduction, removal of surface accretions, and photobiomodulation. The aim of this review was to evaluate the scientific literature to ascertain whether lasers have a beneficial role when used adjunctively in initial non-surgical periodontal therapy. (2) Methods: A PubMed search was performed specifically for randomized clinical trials where a dental laser was used adjunctively for initial periodontal therapy on human patients published from January 2010–April 2020. The first search identified 1294 eligible studies. After additional criteria and filters were applied, 20 manuscripts were included in this review. (3) Results: The chosen manuscripts reported on investigations into initial therapy for patients diagnosed with chronic periodontitis. After periodontal charting, conventional instrumentation such as hand and ultrasonic scaling was performed on all patients in the studies, and then a test group or groups of patients were treated adjunctively with a laser. That adjunctive laser group’s periodontal findings showed various degrees of improved health compared to the group treated with only conventional methods. (4) Conclusion: This systematic review found that 70% of the included studies reported significantly better outcomes in certain clinical parameters, but no improvement in others. The remaining 30% of the manuscripts reported no significant difference in any of the measurements. With consideration to correct parametry, lasers have an adjunctive role in initial non-surgical periodontal therapy.