Periodontal treatment with an Er:YAG laser or scaling and root planing. A 2-year follow-up split-mouth study

Current status of Er:YAG laser in periodontal surgery

Lasers have numerous advantageous tissue interactions such as ablation or vaporization, hemostasis, bacterial killing, as well as biological effects, which induce various beneficial therapeutic effects and biological responses in the tissues. Thus, lasers are considered an effective and suitable device for treating a variety of inflammatory and infectious conditions of periodontal disease. Among various laser systems, the Er:YAG laser, which can be effectively and safely used in both soft and hard tissues with minimal thermal side effects, has been attracting much attention in periodontal therapy. This laser can effectively and precisely debride the diseased root surface including calculus removal, ablate diseased connective tissues within the bone defects, and stimulate the irradiated surrounding periodontal tissues during surgery, resulting in favorable wound healing as well as regeneration of periodontal tissues. The safe and effective performance of Er:YAG laser-assisted periodontal surgery has been reported with comparable and occasionally superior clinical outcomes compared to conventional surgery. This article explains the characteristics of the Er:YAG laser and introduces its applications in periodontal surgery including conventional flap surgery, regenerative surgery, and flapless surgery, based on scientific evidence from currently available basic and clinical studies as well as cases reports.

Erbium lasers in non-surgical periodontal therapy: an umbrella review and evidence gap map analysis

The literature on the efficacy of erbium lasers for nonsurgical periodontal therapy is inconsistent. The objective of the umbrella review was to collate the information available in the systematic reviews to provide a comprehensive synthesis of clinical and patient reported outcomes following the use of erbium lasers for non-surgical periodontal therapy. An electronic database search was carried out, and systematic reviews/meta-analyses which assessed the efficacy of erbium lasers as monotherapy or as an adjunct to scaling and root planing were included. The methodological quality and reporting quality of the included studies were assessed. 15 Systematic reviews/meta-analyses were obtained after title, abstract, and full text search. The meta-analyses data revealed a clinical attachment level gain, reduction in probing pocket depth at 1 and 3-month follow-up, and no additional benefit at ≥ 6-month follow-up in the erbium laser group. The evidence gap map revealed lack of clinical outcome data at > 6-month follow-up and dearth in studies assessing patient reported outcome measures and adverse events. Erbium lasers may provide short-term clinical benefits, and further studies with standardized laser parameters evaluating long-term follow-up, patient-reported outcome measures, and adverse events are needed.

Impact of Air and Manual Scaling on Dental Anxiety and Blood Glucose Level among Diabetic Patients

Aims:

The current study aimed at describing the short-term effect of nonsurgical periodontal treatment on dental anxiety and blood glucose level change among diabetic patients.

Materials and Methods:

One hundred and fifty patients with diabetes participated in a cross-sectional study design. All of them were divided into two groups, with 75 patients in each group. The first group was treated with air scaling, whereas the second group was treated with manual scaling. The determination of treatment needs and the evaluation of periodontal health status were achieved by using Community Periodontal Index for Treatment Need (CPITN). The level of dental anxiety was assessed by using Visual Analogue Scale (VAS). The glucose change was calculated by subtracting the glucose level before treatment from the glucose level straight after treatment.

Results:

No significant difference in glucose level was observed between manual scaling and air scaling after treatment (P = 0.076), and the level of glucose was significantly lower after scaling treatment within the treatment groups (P = 0.000). The level of glucose change between the groups was significantly lower for the manual scaling treatment group (P = 0.013), and it was significantly correlated with VAS (P = 0.000). Multiple regression analysis showed a significant association between the treatment groups (P = 0.007).

Conclusions:

Scaling reduced blood glucose and dental anxiety levels in patients with diabetes. Manual scaling was associated with reduced glucose level change less than air scaling after treatment.

LASER in periodontal treatment: is it an effective treatment or science fiction?

There are several studies that evaluate the use of lasers in periodontal treatment in non-surgical or surgical therapy. However, while several studies showed clinically beneficial effects of some lasers in periodontal treatment, there are few clinical reports of additional advantages of lasers as adjunctive treatments in periodontology. The aim of this paper is to demonstrate and critically analyze the level of scientific evidence of effects of low-level lasers and high-power lasers in periodontology. A narrative review of the studies was carried out in each topic and type of laser or periodontal treatment. In nonsurgical periodontal therapy the results showed that there is an additional clinical benefit when using a diode laser (DL) associated with scaling and root planing (SRP) in patients with moderate to severe periodontitis. The Er:YAG laser seems to be the most suitable for nonsurgical periodontal therapy and promotes the same clinical effects as conventional therapy. In periodontal surgery vaporization of the gingival or mucosal tissue can be carried out with DL, CO2, Nd:YAG, Er:YAG and Er,Cr:YSGG lasers. Photobiomodulation (PBM), mediated by low-level lasers associated with non-surgical periodontal therapy, promotes additional benefits in the short term and accelerates the bone and gingival tissue repair process and also reduces postoperative symptoms of periodontal surgery. The effect of antimicrobial Photodynamic Therapy is relevant in the initial reevaluation periods. Studies have shown controversial results of the use of lasers in periodontics, and this fact may be due to the lack of standard parameters of irradiation in each clinical application.

Erbium-doped: yttrium-aluminum-garnet (Er:YAG) versus scaling and root planing for the treatment of periodontal disease: A single-blinded split-mouth randomized clinical trial

BACKGROUND

This randomized, controlled clinical trial aimed to compare the differences in periodontal clinical outcomes, duration of the procedure, and patient's experience between conventional scaling and root planing and erbium-doped: yttrium-aluminum-garnet (Er:YAG) in the treatment of generalized moderate to severe chronic periodontitis or generalized Stages II or III, and Grade B periodontitis based on the Centers for Disease Control (CDC), American Academy of Periodontology (AAP), and European Federation of Periodontology (EFP) definitions.

METHODS

Thirty subjects were initially recruited. In a split-mouth fashion, right and left sides were randomly allocated into two treatment arms: conventional scaling and root planing (C-SRP) versus laser-assisted scaling and root planing (L-SRP). A blinded examiner recorded clinical measurements at baseline and 3 months. Duration of the procedure was also recorded for each visit, and the patient's experience was assessed with a questionnaire at baseline, 1, and 3 months.

RESULTS

The final sample consisted of 26 subjects. Both treatments resulted in overall improvement, but no significant differences were found between modalities for clinical attachment gain or probing depth reduction. The duration of the procedure was approximately half for L-SRP, and postoperative sensitivity was greater in C-SRP.

CONCLUSIONS

The low-energy protocol with Er:YAG (50 mJ) used for the non-surgical treatment of moderate-severe chronic or Stage II-III, Grade B periodontitis performed in this study population was a treatment modality that yielded similar clinical improvements when compared to conventional scaling and root planing.

Adjunctive laser or antimicrobial photodynamic therapy to non-surgical mechanical instrumentation in patients with untreated periodontitis: A systematic review and meta-analysis

AIM

To compare the adjunctive effects of lasers or antimicrobial photodynamic therapy (aPDT) to non-surgical mechanical instrumentation alone in untreated periodontitis patients.

MATERIALS AND METHODS

Two focused questions were addressed using the Population, Intervention, Comparison and Outcome criteria as follows: in patients with untreated periodontitis, (a) does laser application provide adjunctive effects on probing pocket depth (PPD) changes compared with non-surgical instrumentation alone? and (b) does application of aPDT provide adjunctive effects on PPD changes compared with non-surgical instrumentation alone? Both randomized controlled clinical trials (RCTs) and controlled clinical trials (CCTs) were included. Results of the meta-analysis are expressed as weighted mean differences (WMD) and reported according to the PRISMA guidelines.

RESULTS

Out of 1,202 records, 10 articles for adjunctive laser and 8 for adjunctive aPDT were included. With respect to PPD changes, 1 meta-analysis including 2 articles (total n = 42; split-mouth design) failed to identify a statistically significant difference (WMD = 0.35 mm; 95%CI: -0.04/0.73; p = .08) in favour of adjunctive aPDT (wavelength range 650-700 nm). In terms of adjunctive laser application, a high variability of clinical outcomes at 6 months was noted. Two articles included patient-reported outcomes and 10 reported on the presence/absence of harms/adverse effects.

CONCLUSIONS

Available evidence on adjunctive therapy with lasers and aPDT is limited by (a) the low number of controlled studies and (b) the heterogeneity of study designs. Patient-reported benefits remain to be demonstrated.

Efficacy of laser monotherapy or non-surgical mechanical instrumentation in the management of untreated periodontitis patients. A systematic review and meta-analysis

Objective

To evaluate and compare the effects of laser monotherapy with non-surgical mechanical instrumentation alone in untreated periodontitis patients.

Materials and methods

A focused question was formulated based on the Population, Intervention, Comparison, Outcome, and Study design criteria (PICOS): in patients with untreated periodontitis, does laser mono-therapy provide adjunctive effects on pocket probing depth (PPD) changes compared with non-surgical instrumentation alone? Both randomized controlled clinical trials (RCTs) and controlled clinical trials (CCTs) were included. The results of the meta-analyses are expressed as weighted mean differences (WMD) and reported according to the PRISMA guidelines.

Results

The search yielded 1268 records, out of which 8 articles could be included. With respect to PPD changes, a meta-analysis including 5 articles (n = 148) failed to identify statistically significant differences in favor of laser monotherapy for PPD change (WMD = 0.14 mm; 95% CI: − 0.04/0.32; z = 1.51; p = 0.132) nor for clinical attachment level (CAL) (WMD = 0.04 mm; 95% CI: − 0.35/0.42; z = 0.19; p = 0.850). Data on cost-effectiveness are lacking. One study reported patient-related outcome measures (PROMS).

Conclusions

In untreated periodontitis patients, laser monotherapy does not yield superior clinical benefits compared with non-surgical mechanical instrumentation alone.

Clinical relevance

In untreated periodontitis patients, mechanical instrumentation with hand and/or ultrasonic instruments remains the standard of care.

Clinical and Immunological Effects of Er,Cr:YSGG Laser in Nonsurgical Periodontal Treatment: A Randomized Clinical Trial

Objective: The aim of this study was to compare the clinical and immunological results of nonsurgical periodontal treatment with or without the erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser. Background data: As lasers have begun to be used in dentistry, the Er,Cr:YSGG laser has started to attract attention in the field of periodontology. Materials and methods: Fifty-nine nonsmoking patients with advanced chronic periodontitis were randomly allocated to a test group (full-mouth ultrasonic supra- and subgingival debridement+Er,Cr:YSGG laser application) and a control group (full-mouth ultrasonic supra- and subgingival debridement+root planing with Gracey curettes). The laser parameters were set as follows: 1.5 W output power, pulse mode H (pulse duration of 140 μs), pulse frequency of 20 Hz, and an air-water spray ratio of 10% air and 15% water. The instrumentation was performed until the operator felt that the root surfaces were adequately debrided. Probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), plaque index, interleukin-1 beta (IL-1β), matrix metalloproteinase-8 (MMP-8), tissue inhibitor metalloproteinase-1 (TIMP-1), and MMP-8/TIMP-1 levels in gingival crevicular fluid were evaluated at baseline, 6 weeks, and 3 months postoperatively. Results: There were statistically significant differences in PD, which was our primary outcome, and BOP between the groups at both examinations [p < 0.001 and p < 0.001 (for PD) and p = 0.048 and p < 0.001 (for BOP), respectively], in favor of the laser group. However, there were no significant differences among groups at any time for CAL gain (p = 563 and p = 369, respectively). No significant differences in MMP-8, TIMP-1, and MMP-8/TIMP-1 levels were detected among groups. There was a statistically significant difference for IL-1β levels among groups at 3-month evaluations in favor of the laser group. Conclusions: Using the Er,Cr:YSGG laser instead of hand instruments in nonsurgical periodontal treatment has shown additional improvements in terms of pocket reduction and gingival bleeding compared with traditional nonsurgical therapy.

Comparative Evaluation of the Effects of CO2 and Er:YAG Lasers on Smear Layer Removal and Blood Cell Attachment to Tooth Root Surfaces

Introduction: The tooth root surfaces are modified by different agents for better removal of the smear layer, the formation of fibrin clots, and the attachment of blood cells. This in vitro study compared the removal of the smear layer, the formation of fibrin clots and the attachment of blood cells after exposing periodontally compromised root surfaces to ER:YAG and CO₂ laser beams. Methods: Eighteen dentin block samples were prepared from freshly extracted periodontally compromised teeth that were deemed hopeless, and they were divided into 3 groups: exposed to Er:YAG laser beams, exposed to CO₂ laser beams, and the control group. The samples were evaluated using scanning electron microscopy and micrographs were taken. Smear layer removal and blood cell attachment were scored. Data were analyzed using Kruskal-Wallis and MannWhitney tests. Results: In the Er:YAG laser group, the smear layer was removed completely. In the specimens exposed to blood, better fibrin clot formation and blood cell attachment were observed in the Er:YAG laser group. In the CO₂ laser group, the smear layer was also removed; however, there were no significant differences between the CO₂ laser and control groups in fibrin clot formation and blood cell attachment. Conclusion: The application of the Er:YAG laser to the root dentin appears to result in the formation of a suitable surface for fibrin clot formation and blood cell attachment. Further clinical studies are necessary to support these results.

Photonic Therapy in Periodontal Diseases an Overview with Appraisal of the Literature and Reasoned Treatment Recommendations

Recent reviews and meta-analyses of the literature over the past quarter-century have failed to provide enough evidence to prove or disprove the actual utility of photonic therapy in periodontitis, alone or adjunctive to conventional approaches. This apparent paradox has been explained by the many physical, molecular, biological, anatomical, and technical variables of photonic treatments, which can differ in light-emitting devices (laser or LED), wavelengths, irradiation power and modes, clinical objectives, follow-up times, disease grading, and assessment methods. This multi-faceted, controversial scenario has led practitioners to underestimate the actual potential of photonic therapy in periodontal diseases. In this critical appraisal of the literature, we have briefly summarized the main photonic therapies and instruments used in Periodontology, highlighting their main characteristics and limitations. Then, we have tried to identify and discuss the key methodological issues which can have an impact on the outcome of photonic therapies. Our main goal was to identify the best parameters, settings, and methodologies to perform effective periodontal photonic treatments and to extrapolate some recommendations for clinical use. Should these recommendations find a consensus among periodontologists and be adopted in future clinical studies, they will hopefully contribute to dissipate the present confusion and uncertainty on this complex matter.

[Clinical and microbiologic follow-up evaluations after non-surgical periodontal treatment with Nd: YAG laser and scaling and root planning]

OBJECTIVE

Our research aimed to detect the efficacy of non-surgical periodontal treatment with Nd: YAG laser and scaling and root planning (SRP) for chronic periodontitis.

METHODS

We recruited chronic periodontitis patients who have more than four teeth with clinical pocket depth of 4-8 mm. These teeth were distributed in four different zones within the oral cavity. Moreover, the teeth were single root teeth and not adjacent to each other. The subordinated teeth were randomized into four groups, as follows: no treatment (C group), simple SRP (SRP group), Nd: YAG laser after SRP treatment (SRP+L group), and SRP after Nd: YAG laser treatment (L+SRP group). The four experimental observation points were as follows: before treatment (baseline) and 1 week, 1 month, and 3 months after treatment. We measured clinical indicators and collected subgingival deposits in the four time points to analyze changes of red complex in periodontitis.

RESULTS

The clinical indicators were better in all treatment groups than in the control group. Comparison among treatment groups indicated that the value of bleeding on probing, periodontal probing depth, and clinical attachment loss showed no difference. However, the value of plaque index in SRP+L and L+SRP presented a significant reduction at 3 months after treatment. The percentages of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola in all treatment groups decreased after clinical treatment, and differences were observed among the treatment groups at different time points.

CONCLUSIONS

Non-surgical periodontal treatment with SRP and Nd: YAG laser is not more effective than SRP monotherapy. The sequence of laser treatment and SRP has no significant effect on the treatment. However, SRP with Nd: YAG laser was beneficial for plaque control. Non-surgical periodontal treatment with Nd: YAG laser may be used as an alternative to reduce and control the proliferation of microorganisms in persistent periodontitis, but it still needs further verification.

Diode Laser - A Novel Therapeutic Approach in the Treatment of Chronic Periodontitis in Type 2 Diabetes Mellitus Patients: A Prospective Randomized Controlled Clinical Trial

Introduction: Maturity-onset diabetes mellitus affecting the elderly population is marked by insulin resistance and decreased insulin production. The relationship between periodontitis and diabetes is bidirectional. Type 2 diabetic patients are more prone to chronic periodontitis (CP) and severe periodontitis affects the glycemic control in such patients. Recently, dental diode laser has become an effective tool in controlling CP. To date, very few studies have been conducted to check the efficacy of diode laser in control of periodontal destruction in type 2 diabetes mellitus (DM2) patients. Hence, the need of the study was to evaluate whether diode laser helps improvement of periodontal outcome and reduction in anaerobic bacteria in elderly diabetic patients with CP. Methods: Forty DM2 patients with CP were randomized into group A (control): scaling and root planing (SRP) only and group B (test): SRP followed by soft tissue dental diode laser (808 nm) application. Four patients (2 in each group) were lost during follow up. Clinical parameters, plaque samples and glycated hemoglobin levels were evaluated at both baseline and 90 days post-treatment. Results: Improvement in clinical, microbiological and glycemic parameters were noted in the group that received SRP as well as SRP + LANAP (laser-assisted new attachment procedure). The reductions in clinical parameters were statistically significant after 3 months (P<0.001). The microbial analysis of plaque samples for Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) decreased significantly after 3 months in group B than in group A. Glycated hemoglobin level (HbA1c) decreased significantly after 90 days in both the groups (P<0.001) with more reduction in the SRP+LANAP group (6.49%) in comparison to SRP alone (16.25% vs. 9.76%). However, on the intergroup comparison, the difference in HbA1c reduction was nonsignificant. Conclusion: Laser as an adjunct to SRP is an effective procedure for improving clinical and microbiological parameters in maturity onset diabetes mellitus patients with CP. Also, there was a better improvement in glycemic control in the test group compared to control group after 3 months. Hence, medically compromised patients like DM2 with CP with delayed wound healing can effectively be treated by laser as an adjunct to nonsurgical periodontal therapy for better results.

Assessment of microleakage of class V restored by resin composite and resin-modified glass ionomer and pit and fissure resin-based sealants following Er:YAG laser conditioning and acid etching: in vitro study

Aim

The aim of this study was to make a comparison between microleakage of conventionally restored class V cavities using acid etchant and the ones conditioned by erbium-doped yttrium aluminum garnet (Er:YAG) laser, and also to assess and compare the effectiveness of enamel surface treatments of occlusal pits and fissures by acid etching and conditioned by Er:YAG laser-etch.

Materials and methods

Seventy-two extracted third molars were used in this study. The samples were divided into two major groups: class V cavities and pit and fissure sealants. Each subgroup was divided into conventional acid etching, Er:YAG laser conditioning and conventional acid etching, and combination with Er:YAG laser conditioning (n=12). The teeth were placed in 2% methylene blue dye solution, were sectioned, and were evaluated according to the dye penetration criteria. Two samples per subgroup were chosen for scanning electron microscopic (SEM) analysis.

Results

There was a significant difference between occlusal and cervical margin groups. Laser conventional composite cementum group showed more microleakage values compared to other groups. There was no significant difference between occlusal margin groups. However, there was a significant difference between cervical margin groups in terms of microleakage. In sealant groups, there was a significant difference between laser and conventional with/without laser treatment groups in terms of microleakage.

Conclusion

Based on the results reported in this study, it can be concluded that the application of the Er:YAG laser beneath the resin composite, the resin-modified glass ionomers (GIs), and the fissure sealant placement may be an alternative enamel and dentin etching method to acid etching.

Combined application of Er:YAG and Nd:YAG lasers in treatment of chronic periodontitis. A split-mouth, single-blind, randomized controlled trial

BACKGROUND

The aim of the present study was to compare the effectiveness of combined Er:YAG and Nd:YAG laser therapy to that of scaling and root planing with hand instruments in non-surgical treatment of chronic periodontitis.

MATERIAL AND METHODS

Twenty-five systemically healthy patients with chronic periodontitis were selected for this study. The quadrants were randomly allocated in a split-mouth design to either combined Er:YAG (160 mJ/pulse, 10 Hz) and Nd:YAG laser (100 mJ/pulse, 20 Hz) therapy (test group) or scaling and root planing alone (control group). At baseline, 1 month and 3 months after treatment, plaque index, gingival index, probing depth, clinical attachment level and bleeding on probing (%), were recorded and gingival crevicular fluid and subgingival plaque samples were taken. The gingival crevicular fluid levels of interleukin-1β and tumor necrosis factor-α were analyzed by enzyme-linked immunosorbent assay. Quantitative analysis of red complex bacteria was performed using quantitative real-time polymerase chain reaction.

RESULTS

The clinical parameters had significantly improved for both groups after treatment. There were statistically significant differences in probing depth and clinical attachment level between the test and control groups only for deep pockets (≥7 mm) (P<.05). No significant differences between the two groups were observed for the biochemical and microbiological parameters at any time points (P>.05).

CONCLUSIONS

The present study suggests that a combined course of Er:YAG and Nd:YAG laser therapy may be beneficial particularly in inaccessible areas such as deep pockets on a short-term basis. Further, well-designed studies are required to assess the effectiveness of the combination of these lasers.

Periodontal and peri-implant wound healing following laser therapy

Laser irradiation has numerous favorable characteristics, such as ablation or vaporization, hemostasis, biostimulation (photobiomodulation) and microbial inhibition and destruction, which induce various beneficial therapeutic effects and biological responses. Therefore, the use of lasers is considered effective and suitable for treating a variety of inflammatory and infectious oral conditions. The CO2 , neodymium-doped yttrium-aluminium-garnet (Nd:YAG) and diode lasers have mainly been used for periodontal soft-tissue management. With development of the erbium-doped yttrium-aluminium-garnet (Er:YAG) and erbium, chromium-doped yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers, which can be applied not only on soft tissues but also on dental hard tissues, the application of lasers dramatically expanded from periodontal soft-tissue management to hard-tissue treatment. Currently, various periodontal tissues (such as gingiva, tooth roots and bone tissue), as well as titanium implant surfaces, can be treated with lasers, and a variety of dental laser systems are being employed for the management of periodontal and peri-implant diseases. In periodontics, mechanical therapy has conventionally been the mainstream of treatment; however, complete bacterial eradication and/or optimal wound healing may not be necessarily achieved with conventional mechanical therapy alone. Consequently, in addition to chemotherapy consisting of antibiotics and anti-inflammatory agents, phototherapy using lasers and light-emitting diodes has been gradually integrated with mechanical therapy to enhance subsequent wound healing by achieving thorough debridement, decontamination and tissue stimulation. With increasing evidence of benefits, therapies with low- and high-level lasers play an important role in wound healing/tissue regeneration in the treatment of periodontal and peri-implant diseases. This article discusses the outcomes of laser therapy in soft-tissue management, periodontal nonsurgical and surgical treatment, osseous surgery and peri-implant treatment, focusing on postoperative wound healing of periodontal and peri-implant tissues, based on scientific evidence from currently available basic and clinical studies, as well as on case reports.

Comparison of Er:YAG Laser and Ultrasonic Scaler in the Treatment of Moderate Chronic Periodontitis: A Randomized Clinical Trial

Introduction: Periodontitis is an inflammatory periodontal disease that leads to tooth loss. Recently laser has been introduced as an alternative treatment for periodontitis. The aim of the present study was to compare the effect of Erbium-doped Yttrium Aluminum Garnet (Er:YAG) laser with ultrasonic scaler in patients with moderate chronic periodontitis. Methods: In this randomized single-blind clinical trial, 27 patients with moderate chronic periodontitis were selected. One quadrant of the patients was treated by Er:YAG laser and the other one by ultrasonic scaler. Clinical parameters, including periodontal pocket depth (PPD), papillary bleeding index (PBI) and clinical attachment level (CAL) were measured before, as well as 6 and 12 weeks after treatment. Data were analyzed by SPSS 20 software using Friedman test, paired t test, independent t test and Mann-Whitney test. The significance level was set at 0.05. Results: The means of clinical parameters in both groups were significantly improved in the first and second follow-ups (P < 0.001). Although the means of PPD, PBI and CAL were slightly higher in the laser group than in the ultrasonic group, the differences were not statistically significant between these two groups (P > 0.05). Conclusion: Although both ultrasonic scaler and Er:YAG laser could effectively improve clinical periodontal parameters, the results did not reveal the superiority of Er:YAG laser over ultrasonic scaler or vice versa.

Energy output reduction and surface alteration of quartz tips following Er:YAG laser contact irradiation on soft and hard tissues in vitro

Though the Er:YAG laser (ErL) has been used in periodontal therapy, the irradiated tip damage has not been studied in detail. In this study, the change in the energy output, surface morphology, and temperature of quartz tips was evaluated following contact irradiation. Soft tissue, calculus on extracted human teeth, and porcine bone were irradiated by ErL for 60 min at 14.2 or 28.3 J/cm(2)/pulse and 20 Hz with or without water spray. The energy output ratio declined the most in the calculus group, followed by the bone and soft tissue groups with and/or without water spray. Carbon contamination was detected in all groups, and contamination by P, Ca, and/or other inorganic elements was observed in the calculus and bone groups. The rate of energy output reduction and the degree of surface alteration/contamination is variously influenced by the targeting tissue, temperature elevation of the tip and water spray.

Laser assisted periodontics: A review of the literature

Over the years, the use of the laser within health field and more particularly dentistry has been increasing and improving. The application of laser in the periodontal treatment takes part of a non-surgical and surgical approaches, is used for the decontamination of periodontal pockets due to its bactericidal effect, and the removal of granulation tissues, inflamed and diseased epithelium lining, bacterial deposits and subgingival calculus. However in spite of all the marketing surrounding, the use of laser highlighting its beneficial effect, the capacity of laser to replace the conventional treatment for chronic periodontitis is still debatable. In fact there is no evidence that any laser system adds substantial clinical value above conventional treatments of chronic periodontitis. Some studies showed a significant positive effect on clinical attachment level gain and probing depth reduction. In the other hand, several articles demonstrated no evidence of the superior effectiveness of laser therapy compared to root planing and scaling. Our aims is to review the literature on the capacity of erbium:Yttrium-aluminum-garnet and neodymium:Yttrium-aluminium-garnet laser to either replace or complete conventional mechanical/surgical periodontal treatments.

Microbiological effects and recolonization patterns after adjunctive subgingival debridement with Er:YAG laser

OBJECTIVES

The objective of this study was to assess the microbiological effects and recolonization patterns after non-surgical periodontal treatment protocol based on the adjunctive use of erbium-doped yttrium aluminium garnet (Er:YAG) laser.

MATERIAL AND METHODS

Patients diagnosed with chronic periodontitis were randomly assigned to two different treatment protocols: test, full-mouth subgingival ultrasonic instrumentation followed by Er-YAG laser application 1 week later to sites with initial probing pocket depth ≥4.5 mm; and control, full-mouth ultrasonic subgingival instrumentation within 1 week. Clinical (at sampled sites) and microbiological (culture-based) parameters were recorded at baseline and 3 and 12 months. Microbiological variables included total counts, frequency of detection, proportions and counts of target species.

RESULTS

Results from 19 test and 21 control patients were compared. Minor changes were observed for total colony-forming units, with no differences between groups. For the frequency of detection, a limited and similar impact in both groups was observed for the most prevalent (over 80 %) periodontal pathogens (Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum). For proportions, reductions in P. gingivalis occurred at 3 months, both in the test and control groups (from 16.3 to 10 % and 16 to 14.8 %, respectively), although these differences were not statistically significant. At 12 months, the test group showed a statistically significant greater reduction in probing depth for the sampled sites.

CONCLUSIONS

The adjunctive use of Er:YAG laser when compared with conventional ultrasonic debridement did not provide a microbiological added benefit.

CLINICAL RELEVANCE

Even though some clinical benefits with the adjunctive laser application were identified when comparing both treatment protocols, there were no differences in microbiological outcomes or in the bacterial recolonization patterns.

Effect of Nonsurgical Periodontal Treatment Combined With Diode Laser or Photodynamic Therapy on Chronic Periodontitis: A Randomized Controlled Split-Mouth Clinical Trial

INTRODUCTION

The optimum removal of bacteria and their toxins from periodontal pockets is not always obtained by conventional mechanical debridement. Adjunctive therapies may improve tissue healing through detoxification and bactericidal effects. The purpose of the present study was to evaluate the impact of adjunctive laser therapy (LT) and photodynamic therapy (PDT) on patients with chronic periodontitis.

METHODS

Twenty patients with at least three quadrants involved and each of them presenting pockets 4-8 mm deep were included in the study. Periodontal treatment comprising scaling and root planning (SRP) was accomplished for the whole mouth. Applying a split-mouth design, each quadrant was randomly treated with SRP alone (group A), SRP with LT (group B), and SRP with PDT (group C). The clinical indices were measured at baseline 6 weeks and 3 months after treatment. Microbiological samples were taken and evaluated at baseline and 3-month follow-up.

RESULTS

All groups showed statistically significant improvements in terms of clinical attachment level (CAL) gain, periodontal pocket depth (PPD) reduction, papilla bleeding index and microbial count compared to baseline (P < .05). The results showed more significant improvement in the 6-week evaluation in terms of CAL in groups B and C than in group A (P < .05). Group B also revealed a greater reduction in PPD than the other treatment modalities (P < .05).

CONCLUSION

The obtained data suggested that adjunctive LT and PDT have significant short-term benefits in the treatment of chronic periodontitis. Furthermore, LT showed minimal additional advantages compared to PDT.

Laser supported reduction of specific microorganisms in the periodontal pocket with the aid of an Er,Cr:YSGG laser: a pilot study

OBJECTIVE

The aim of this study was to evaluate the effectiveness of a radial firing tip of an Er,Cr:YSGG laser as an adjunct to a nonsurgical periodontal treatment.

METHODS

Twelve patients with chronic or aggressive periodontitis were treated by conventional periodontal treatment using ultrasonic devices and hand instruments and, additionally, in two quadrants with an Er,Cr:YSGG laser. A new radial firing tip (RFPT 14-5, Biolase) was used with 1.5 W, 30 Hz, 11% air, 20% water, and pulse duration 140 μs. Microbiological smears were taken before treatment, one day after lasing, and three and six months after lasing. Pocket depths of all periodontal sites were measured before and six months after treatment.

RESULTS

The total bacterial load of Prevotella intermedia, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans inside the pocket was reduced significantly throughout the whole examination time. Greater pocket depth reductions were observed in all groups. There was a slight higher reduction of pocket depth in the lased group after six months.

CONCLUSIONS

These results support the thesis that Er,Cr:YSGG laser supported periodontal treatment leads to a significant reduction of periopathogenes and thereby helps the maintenance of periodontal health.

Intrapulpal temperature changes during root surface irradiation with dual-wavelength laser (2780 and 940 nm): in vitro study

This work reports that the ablation volume and rate of porcine skin changed significantly with the change of skin water content. Under the same laser irradiation conditions (532 nm Nd:YAG laser, pulse width = 11.5 ns, pulse energy = 1.54 J, beam radius = 0.54 mm), the ablation volume dropped by a factor of 4 as the skin water content decreased from 40 wt. % (native) to 19 wt. % with a change in the ablation rate below and above around 25 wt. %. Based on the ablation characteristics observed by in situ shadowgraph images and the calculated tissue temperatures, it is considered that an explosive rupture by rapid volumetric vaporization of water is responsible for the ablation of the high water content of skin, whereas thermal disintegration of directly irradiated surface layer is responsible for the low water content of skin.

Er:YAG laser versus scaling and root planing as alternative or adjuvant for chronic periodontitis treatment: a systematic review

AIM

To perform a systematic review to evaluate the erbium-doped: yttrium, aluminium and garnet (Er:YAG) laser versus scaling and root planing (SRP) as alternative or adjuvant for chronic periodontitis treatment.

MATERIAL AND METHODS

We performed a literature search using six electronic databases and completed by manual searches up to July 2013. We conducted a meta-analysis as well as heterogeneity, sensitivity, subgroup and power analyses to clarify and validate the pooled results. The 3-, 6- and 12-month clinical outcomes were evaluated.

RESULTS

Twelve eligible randomized clinical trials were finally included. Our meta-analysis showed that Er:YAG laser resulted in similar clinical improvements as SRP 3 months postoperatively. For subgroups by laser level, quality of trials and fluorescence feedback device, the results remained consistent. The 6- and 12-month observations between Er:YaG laser and SRP demonstrated no difference but inconclusive, due to large heterogeneity. The advantage of Er:YAG laser adjuvant to SRP for periodontitis treatment was not significant.

CONCLUSIONS

This systematic review indicated that the clinical efficacy of Er:YAG laser was similar to SRP 3 months postoperatively. The clinical benefits of Er:YAG laser as adjuvant to SRP was still lacking. Since Er:YAG laser has certain advantages, it could be expected to be a novel short-term alternative choice for chronic periodontitis.

Effects of root surface debridement using Er:YAG laser versus ultrasonic scaling - a SEM study

OBJECTIVE

Despite promising results of Er:YAG laser in periodontal debridement, to date there is no consensus about the ideal settings for clinical use. This experimental clinical trial aimed to determine the effects of debridement using Er:YAG laser and to compare with ultrasonic treatment.

MATERIALS AND METHODS

Sixty-four teeth were divided into two in vivo and in vitro subgroups. Each tooth received ultrasonic treatment on one side and Er:YAG laser debridement at either 60, 100, 160 or 250 mJ pulse(-1) and at 10 Hz on the other side on a random basis. All samples were morphologically analyzed afterwards under scanning electron microscope for surface changes and dentinal tubules exposure. Treatment duration (d) was also recorded.

RESULTS

Laser debridement produced an irregular, rough and flaky surface free of carbonization or meltdown while ultrasound produced a relatively smoother surface. The number of exposed dentinal tubules (n) followed an energy-dependent trend. The number of exposed tubules among the in vivo laser groups was n 60 mJ = n 100 mJ < n 160 mJ < n 250 mJ (P < 0.001). Also 160 and 250 mJ lasers led to significantly more dentinal exposure than ultrasound under in vivo condition. Within the in vitro laser groups, dentinal tubules exposure was n 60 mJ < n 100 mJ < n 160 mJ < n 250 mJ (P ≤ 0.0015). Furthermore, in vitro laser treatments at 100, 160 and 250 mJ led to significantly more dentinal denudation than ultrasound. Treatment duration (d) for the in vivo groups was d 60 mJ > d 100 mJ > d Ultrasound = d 160 mJ > d 250 mJ (P ≤ 0.046), while for the in vitro groups it was d 60 mJ > d 100 mJ = d Ultrasound = d 160 mJ >d 250 mJ (P ≤ 0.046).

CONCLUSIONS

Due to excessive treatment duration and surface damage, Er:YAG laser debridement at 60 and 250 mJ pulse(-1), respectively, is not appropriate for clinical use. Although laser debridement at 100 and 160 mJ pulse(-1) seems more suitable for clinical application, compared to ultrasound the former is more time-consuming and the latter is more aggressive. Using a feedback device or lower pulse energies are recommended when using laser in closed field.

Anti-infective therapy with an Er:YAG laser: influence on peri-implant healing

In addition to conventional treatment modalities (mechanical and chemical), the use of lasers has been increasingly proposed for the treatment of periodontal and peri-implant infections (i.e., cleaning and detoxification of implant surfaces). Preliminary results from basic studies have pointed to the high potential of the Erbium-doped: Yttrium, Aluminum and Garnet (Er:YAG) laser. Furthermore, preliminary clinical data indicate that treatment with this kind of laser may positively influence peri-implant healing. The aim of this research update is to evaluate, based on the currently available evidence, the use of an Er:YAG laser for the treatment of peri-implant infections and to indicate its potential as a new treatment modality.

A comparative scanning electron microscopy study between hand instrument, ultrasonic scaling and erbium doped:Yttirum aluminum garnet laser on root surface: A morphological and thermal analysis

BACKGROUND AND OBJECTIVES

Scaling and root planing is one of the most commonly used procedures for the treatment of periodontal diseases. Removal of calculus using conventional hand instruments is incomplete and rather time consuming. In search of more efficient and less difficult instrumentation, investigators have proposed lasers as an alternative or as adjuncts to scaling and root planing. Hence, the purpose of the present study was to evaluate the effectiveness of erbium doped: Yttirum aluminum garnet (Er:YAG) laser scaling and root planing alone or as an adjunct to hand and ultrasonic instrumentation.

SUBJECTS AND METHODS

A total of 75 freshly extracted periodontally involved single rooted teeth were collected. Teeth were randomly divided into five treatment groups having 15 teeth each: Hand scaling only, ultrasonic scaling only, Er:YAG laser scaling only, hand scaling + Er:YAG laser scaling and ultrasonic scaling + Er:YAG laser scaling. Specimens were subjected to scanning electron microscopy and photographs were evaluated by three examiners who were blinded to the study. Parameters included were remaining calculus index, loss of tooth substance index, roughness loss of tooth substance index, presence or absence of smear layer, thermal damage and any other morphological damage.

RESULTS

Er:YAG laser treated specimens showed similar effectiveness in calculus removal to the other test groups whereas tooth substance loss and tooth surface roughness was more on comparison with other groups. Ultrasonic treated specimens showed better results as compared to other groups with different parameters. However, smear layer presence was seen more with hand and ultrasonic groups. Very few laser treated specimens showed thermal damage and morphological change.

INTERPRETATION AND CONCLUSION

In our study, ultrasonic scaling specimen have shown root surface clean and practically unaltered. On the other hand, hand instrument have produced a plane surface, but removed more tooth structure. The laser treated specimens showed rough surfaces without much residual deposit or any other sign of morphological change.

Ailing and failing oral implants: initial therapy and surgical management

The distinction between ailing and failing implants is clinically important. Changes in the peri-implant soft or hard tissues will indicate whether the implant is ailing, failing, or has failed. This article discusses these clinical situations and provides an overview and description of peri-implant diseases and their treatment alternatives.

Histological and SEM analysis of root cementum following irradiation with Er:YAG and CO2 lasers

Recently, the Er:YAG and CO(2) lasers have been applied in periodontal therapy. However, the characteristics of laser-irradiated root cementum have not been fully analyzed. The aim of this study was to precisely analyze the alterations of root cementum treated with the Er:YAG and the CO(2) lasers, using non-decalcified thin histological sections. Eleven cementum plates were prepared from extracted human teeth. Pulsed Er:YAG laser contact irradiation was performed in a line at 40 mJ/pulse (14.2 J/cm(2)/pulse) and 25 Hz (1.0 W) under water spray. Continuous CO(2) laser irradiation was performed in non-contact mode at 1.0 W, and ultrasonic instrumentation was performed as a control. The treated samples were subjected to stereomicroscopy, scanning electron microscopy (SEM), light microscopy and SEM energy dispersive X-ray spectroscopy (SEM-EDS). The Er:YAG laser-treated cementum showed minimal alteration with a whitish, slightly ablated surface, whereas CO(2) laser treatment resulted in distinct carbonization. SEM analysis revealed characteristic micro-irregularities of the Er:YAG-lased surface and the melted, resolidified appearance surrounded by major and microcracks of the CO(2)-lased surface. Histological analysis revealed minimal thermal alteration and structural degradation of the Er:YAG laser-irradiated cementum with an affected layer of approximately 20-μm thickness, which partially consisted of two distinct affected layers. The CO(2)-lased cementum revealed multiple affected layers showing different structures/staining with approximately 140 μm thickness. Er:YAG laser irradiation used with water cooling resulted in minimal cementum ablation and thermal changes with a characteristic microstructure of the superficial layer. In contrast, CO(2) laser irradiation produced severely affected distinct multiple layers accompanied by melting and carbonization.

Minimally Invasive Periodontal Treatment Using the Er,Cr: YSGG Laser. A 2-year Retrospective Preliminary Clinical Study

Minimally invasive surgery (MIS) using the erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser (Waterlase MD, Biolase, Irvine, CA) to treat moderate to advanced periodontal disease is presented as an alternative to conventional therapies. To date, there are few short- or long-term studies to demonstrate the effects of this laser in treating and maintaining periodontal health. Electronic clinical records from 16 patients – total of 126 teeth, with pocket depths ranging from 4 mm to 9 mm – were treated with the same protocol using the Er,Cr:YSGG laser. The mean baseline probing depths (PD) were 5 mm and clinical attachment levels (CAL) were 5 mm in the 4 - 6 mm pretreated laser group. The mean baseline probing depths were 7.5 and 7.6 mm for PD and CAL respectfully in the 7 – 9 mm pretreatment laser group. At the 2 year mark, the average PD was 3.2 ± 1.1 mm for the 4-6 mm pocket group and the 7-9 mm pocket group had a mean PD of 3.7 ± 1.2 mm. mean CAL was 3.1 ± 1.1 mm for the 4-6 mm group and 3.6 ± 1.2 for the 7-9 mm group with an overall reduction of 1.9 mm and 4.0 mm respectively. At one and two years, both groups remained stable with PD comparable to the three-month gains. The CAL measurements at one and two years were also comparable to the three-month gains.

Comparison between scaling-root-planing (SRP) and SRP/photodynamic therapy: six-month study

INTRODUCTION

The purpose of this long-term clinical study was to examine the additional efficacy of photodynamic therapy (PDT) to scaling and root planing (SRP) in patients with chronic periodontal disease.

METHODS

A total of 22 patients (mean age: 59.3 ± 11.7 years) with chronic periodontal disease and four teeth with probing depth ≥ 5 mm were enrolled in the study. Inclusion criteria were: no systemic disease, no smoking, no pregnancy and no long-term medication. Beside the anamnesis, the following clinical parameters were assessed at baseline (one week before therapy), and one, three and six months after the therapy: bleeding on probing (BOP), plaque index (PI) probing depth (PD), and clinical attachment loss. All measurements were done by the same examiner with a fixed periodontal probe (PCP 12, Hu-Friedy) at six measurements/tooth. In each patient, two teeth were treated with SRP alone and two teeth with SRP and PDT (Periowave, Ondine Biopharma, Vancouver, Canada). The nonparametric Wilcoxon test for paired samples was used for comparison of the effect of the two treatments (p ≤ 0.05).

RESULTS

After both types of treatment, the number of teeth positive for BOP declined. At baseline, the CAL measured 7.2 ± 1.2 mm (SRP) or 8.1 ± 1.3 mm (SRP/PDT); one, three and six months after both types of treatment an improvement was observed. At baseline, the probing depth was 5.9 ± 0.8 mm (SRP) or 6.4 ± 0.8 mm (SRP/PDT); after six months, an improvement of 2.4 ± 0.6 mm (SRP) or 2.9 ± 0.8 mm (SRP/PDT) was found. The greater reduction of the PD, achieved by a combination of SRP/PDT, was statistically significant after six months (p = 0.007).

CONCLUSION

This clinical study demonstrates that SRP in combination with PDT seems to be effective and is therefore suitable as an adjuvant therapy to the mechanical conditioning of the periodontal pockets in patients with chronic periodontal diseases.

Er:YAG laser treatment in supportive periodontal therapy

OBJECTIVE

To assess clinical and microbiological outcomes of an Er:YAG laser in comparison with sonic debridement in the treatment of persistent periodontal pockets in a prospective randomized controlled multicentre study design.

MATERIAL AND METHODS

A total of 78 patients in supportive periodontal therapy with two residual pockets were included, 58 were available for the whole follow-up period. Root surfaces were instrumented either with a sonic scaler (Sonicflex(®) 2003 L) or with an Er:YAG laser (KEY Laser(®) 3). Clinical attachment levels (CAL), Probing depths (PD), Plaque control record (PCR) and Bleeding on probing (BOP) were assessed at baseline, 13 and 26 weeks after treatment. In addition, microbiological analysis was performed employing a DNA diagnostic test kit (micro-IDent(®) Plus).

RESULTS

Probing depths and CAL were significantly reduced in both groups over time (p < 0.05), without significant differences between the groups (p > 0.05). BOP frequency values decreased significantly within both groups (p < 0.05), with no difference between the laser and the sonic treatment (p > 0.05). PCR frequency values did not change during the observation period (p > 0.05). Microbiological analysis failed to expose any significant difference based on treatment group or period.

CONCLUSION

Employing both sonic and laser treatment procedures during supportive periodontal care, similar clinical and microbiological outcomes can be expected.

Effect of erbium-doped: yttrium, aluminium and garnet laser irradiation on the surface microstructure and roughness of sand-blasted, large grit, acid-etched implants

PURPOSE

The present study was performed to evaluate the effect of erbium-doped: yttrium, aluminium and garnet (Er:YAG) laser irradiation on sand-blasted, large grit, acid-etched (SLA) implant surface microstructure according to varying energy levels and application times of the laser.

METHODS

The implant surface was irradiated by the Er:YAG laser under combined conditions of 100, 140, or 180 mJ/pulse and an application time of 1 minute, 1.5 minutes, or 2 minutes. Scanning electron microscopy (SEM) was used to examine the surface roughness of the specimens.

RESULTS

All experimental conditions of Er:YAG laser irradiation, except the power setting of 100 mJ/pulse for 1 minute and 1.5 minutes, led to an alteration in the implant surface. SEM evaluation showed a decrease in the surface roughness of the implants. However, the difference was not statistically significant. Alterations of implant surfaces included meltdown and flattening. More extensive alterations were present with increasing laser energy and application time.

CONCLUSIONS

To ensure no damage to their surfaces, it is recommended that SLA implants be irradiated with an Er:YAG laser below 100 mJ/pulse and 1.5 minutes for detoxifying the implant surfaces.

Efficacy of Er:YAG laser in the treatment of chronic periodontitis: systematic review and meta-analysis

Scaling root planing (SRP) has been proven efficacious as the traditional treatment approach for chronic periodontitis. However, important limitations such as difficult access in deep pockets, grooves, and furcations have led to the development of new therapeutic strategies. The erbium-doped:yttrium-aluminium-garnet (Er:YAG) laser is one of the most promising laser types for periodontal therapy. Its efficacy in radicular debris removal and root smoothing has been proven in vitro. However, the clinical effectiveness of the Er:YAG laser remains controversial. The aim of the present systematic review was to systemically assess the scientific evidence for the effectiveness of Er:YAG laser compared to SRP in the treatment of chronic periodontitis. Electronic database searches of MEDLINE, Cochrane Controlled Clinical Trial Register, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, CINAHL, Science Direct, ISI Web of Science, and SCOPUS were performed, as well as hand-searching of relevant journals through December 23, 2010. Quality assessment was made according to the CONSORT guidelines. The systematic review was performed according to the QUOROM statement and Cochrane Collaboration recommendations. Meta-analyses of the clinical attachment level gain, probing depth reduction, and changes in gingival recession were performed using weighted mean differences for continuous data with 95% confidence intervals, nested in a random effect model. No statistically significant differences were found in any of the investigated clinical parameters among the five random controlled trials (RCTs) entered into the study, indicating that there was no evidence of effectiveness. However, significant heterogeneity, a high risk of bias in three of the five included studies, and methodological shortcomings indicate that the results should be considered with caution. Future long-term, well-designed RCTs are needed to assess the scientific evidence of Er:YAG laser efficacy as an alternative treatment strategy to SRP.

Influence of the angle of irradiation of the Er,Cr:YSGG laser on the morphology, attachment of blood components, roughness, and root wear: in vitro study

BACKGROUND AND OBJECTIVES

To evaluate the influence of the working tip angulation of the Er,Cr:YSGG laser on the morphology, attachment of blood components, roughness, and wear on irradiated root surfaces compared to scaling and root planing (SRP).

STUDY DESIGN/MATERIALS AND METHODS

The present study used 45 teeth, of which 25 were used for the analysis of the morphology and the attachment of blood components and 20 were used for the analysis of the roughness and of the root wear. The teeth were randomly divided into five groups according to the treatment applied: (G1) Laser Er,Cr:YSGG-30°; (G2) Laser Er,Cr:YSGG-45°; (G3) Laser Er,Cr:YSGG-60°; (G4) Laser Er,Cr:YSGG-90°; and (G5) SRP.

RESULTS

The root surfaces irradiated with the Er,Cr:YSGG laser working angulation tip of 45° and 60°, and the samples scaled with manual instruments presented greater attachment of blood components than the group where the Er,Cr:YSGG laser irradiated at working tip angulation of 30° and 90° (P<0.05). The samples irradiated with the Er,Cr:YSGG laser were rougher than the samples scaled with manual instruments (P<0.05). The group that was irradiated with the Er,Cr:YSGG laser at an angle of 30° presented the least wear in comparison to all the other treatments (P<0.01).

CONCLUSIONS

The irradiated root surfaces proved to be rougher than those scaled with manual instruments; however, irradiation at working tip angulations of 45° and 60° produced results of attachment of blood components and root wear comparable with those obtained with manual instrumentation.