Efficacy of NaOCl/H2O2 irrigation and GaAlAs laser in decontamination of root canals in vitro

BACKGROUND AND OBJECTIVES: To investigate the bactericidal effect of an 809 nm semiconductor laser alone, and in combination with NaOCl/H(2)O(2) irrigation in root canals in vitro. STUDY DESIGN/MATERIALS AND METHODS: A total of 72 human single-rooted teeth extracted for periodontal reasons were included. The crowns were removed, the roots shortened to a length of 12 mm, and the canals enlarged up to an apical size of #50 file. The specimens were autoclaved and incubated with a suspension of Streptococcus sanguinis (ATCC 10556). Laser irradiation was performed on a PC-controlled XY translation stage. A 200 micron optic fiber was used. Twelve specimens were irradiated at a power output of 1.5, 3.0, and 4.5 W in the cw-mode. The total irradiation time was 60 seconds per canal. Twelve specimens were rinsed with NaOCl and H(2)O(2) only, 12 were rinsed and laser treated, and 12 served as untreated controls. After laser treatment, the specimens were sonicated and the bacterial growth was examined by counting colony forming units on blood agar plates. Temperature changes at the outer root surface during irradiation were registered by means of thermocouples. Treated and control specimens were investigated by means of scanning electron microscopy. RESULTS: Mean bacterial reductions of 0.35 log steps at a power output of 1.5 W, 1.44 at 3.0 W, and 2.84 at 4.5 W were calculated. Bacterial reduction by the NaOCl/H(2)O(2) solution alone was 1.48 and comparable to that achieved by irradiation at 3.0 W. With a log kill 2.85, the combination of rinsing and laser irradiation at 3.0 W resulted in a further significant bacterial reduction as compared to rinsing alone (P = 0.004). Irradiation did not result in excessive heat generation at the root surface. Carbonization of the root canal wall was observed in single teeth at 3.0 and 4.5 W and no controlled sealing of the dentinal tubules could be achieved in the root canal. CONCLUSIONS: The application of the diode laser might be an adjunct to conventional endodontic treatment when used in combination with a NaOCl/H(2)O(2) solution.     

Bactericidal effect of different laser systems in the deep layers of dentin

BACKGROUND AND OBJECTIVES: In recent years, various laser systems have gained importance in the field of laser-assisted endodontics, namely the Nd:YAG, the diode, the Er:YAG, and the Er,Cr:YSGG laser. Individual studies have been carried out so far, focusing on the respective wavelength, its specific bactericidal capabilities, and potential usefulness is root-canal disinfection. The present in vitro investigation however, was performed to compare the microbicidal effect of these laser systems under standardized conditions and to draw a conclusion upon their relative effectiveness in the deep layers of dentin. STUDY DESIGN/MATERIALS AND METHODS: In total, 360 slices of root dentin with a thickness of 1 mm were obtained by longitudinal cuts of freshly extracted human premolars. The samples were steam sterilized and subsequently inoculated with a suspension of either Escherichia coli or Enterococcus faecalis. After the incubation, the samples were randomly assigned to the four different laser systems tested. Each laser group consisted of two different operational settings and a control. The dentinal samples underwent "indirect" laser irradiation through the dentin from the bacteria-free side and were then subjected to a classical quantitative microbiologic evaluation. To assess the temperature increase during the irradiation procedure, additional measurements were carried out using a thermocouple. RESULTS: Microbiology indicated that all laser systems were capable of significant reductions in both test strains. At an effective output power of 1 W, E. coli was reduced by at least three log steps in most of the samples by the tested wavelengths, with the best results for the Er:YAG laser showing complete eradication of E. coli in 75% of the samples. E. faecalis, a stubborn invader of the root canal, showed minor changes in bacterial count at 1 W. Using the higher setting of 1.5 W, significant reductions of E. coli were again observed with all laser systems, where only the diode and the Er:YAG laser were capable of complete eradication of E. faecalis to a significant extent. There was no significant relation between the temperature increase and the bactericidal effect. CONCLUSIONS: The present study demonstrates that all the wavelengths investigated are suitable for the disinfection of even the deeper layers of dentin and may prove to constitute valuable tools in state-of-the-art endodontics.     

四种经尿道前列腺剜除术的疗效和安全性比较

目的比较不同手术治疗良性前列腺增生症(BPH)的有效性和安全性。方法回顾性分析2018年1月至2019年7月入住空军军医大学唐都医院的277例手术治疗的BPH患者的临床资料。其中第二代半导体红激光前列腺剜除(DiLEP)手术组88例,钬激光前列腺剜除(HoLEP)手术组50例,经尿道前列腺等离子双极电切剜除术(PKEP)手术组85例,铥激光前列腺剜除(THuVEP)手术组54例,比较4组手术病例手术时间、术后血红蛋白下降值、术后最大尿流率(Qmax)改善值、术后并发症、手术后国际前列腺症状评分(IPSS)改善等参数,分析4种手术方法的疗效与安全性。结果手术均获成功,HoLEP、DiLEP、PKEP、THuVEP4组患者年龄分别为(68.84±6.28)、(70.94±6.14)、(70.31±7.33)、(70.37±5.87)岁,前列腺体积分别为(61.85±16.51)、(61.23±17.37)、(58.40±17.04)、(63.82±19.68)mL,差异均无显著性统计学意义(P>0.05);而手术时间[(94.24±39.13)、(93.67±50.31)、(117.25±62.99)、(97.46±40.62)min]、血红蛋白下降值[(8.40±5.18)、(9.80±5.22)、(11.89±8.18)、(10.48±4.39)g/L]、IPSS评分改善值[(13.14±5.43)、(13.42±3.93)、(11.38±4.55)、(12.20±4.56)分]以及最大尿流率(Qmax)改善值[(17.42±4.87)、(14.89±2.69)、(14.58±4.76)、(15.17±3.08)mL/s],4项指标差异均有显著性统计学意义(P<0.05)。结论与PKEP相比,HoLEP与DiLEP手术时间短、术中止血效果好、术后前列腺症状改善明显;THuVEP手术时间短;DiLEP尿失禁发生率较低,具有良好的安全性。     

1470 nm激光三沟逆切法汽化剜除术治疗良性前列腺增生症的效果分析

目的:探讨1 470nm激光三沟逆切法汽化剜除术(1 470nm diode laser vapoenucleation of the prostate-three passageway antidrom,DiLEP-TPA)治疗良性前列腺增生症(BPH)的临床疗效。方法:回顾性分析2015年1月~2016年1月于我院行DiLEP-TPA治疗54例BPH患者的临床资料,观察其围手术期指标、术后并发症情况及手术前后患者国际前列腺症状评分(IPSS)、生活质量评分(QOL)、残余尿量(PVR)、最大尿流率(Q_max)变化。结果:所有手术顺利完成,无中转经尿道前列腺电切术(TURP)及开放手术。手术时间平均(63.8±11.6)min,膀胱冲洗时间平均(25.0±3.0)h,留置尿管时间平均(52.3±12.4)h,住院时间平均(2.9±0.8)d,术中出血量平均为(45.4±10.9)ml,术后2h血红蛋白减少量平均(2.3±0.9)g/L。术后6个月患者IPSS、QOL、PVR、Q_max均较术前明显改善(P<0.01)。术中无明显出血,无包膜穿孔、膀胱及直肠损伤病例;术后无输血、永久性尿失禁、电切综合征(TURS)等发生。结论:DiLEP-TPA治疗BPH安全、有效。     

Comparative bactericidal exposures for selected oral bacteria using carbon dioxide laser radiation

Although relatively high CO2 laser energies have been shown to sterilize root canals, the response of several bacterial strains to decreasing exposures of CO2 laser energy remains unknown. Freshly grown bacterial cells were irradiated on glass microscope coverslips. A comparison of equivalent energy exposures with differing parameters was made on the bacterial viability. No statistically significant difference was found in the energy required to kill closely related bacterial species. However, the energy density required to kill greater than 99.5% of the bacteria is less than 200 J/cm2, much less than that shown to sterilize in a previous study.     

Lipolysis Using a 980-nm Diode Laser: A Retrospective Analysis of 534 Procedures

Background  The safety and efficacy of the 980-nm diode laser for laser lipolysis were evaluated in different body areas. Methods  From June 2005 to June 2007, 334 subjects underwent laser lipolysis. The treatment was performed using a 980-nm diode laser (OSYRIS, Hellemmes, France). After tumescent anesthesia, a 1-mm-diameter microcannula housing a 600-μm optical fiber was inserted into the subcutaneous fat. The cannula was moved back and forth in a predetermined manner to get a homogeneous distribution of energy at the treated area. Laser settings (power and cumulative energy) were selected in relation to individual body areas: 6 W (chin, arm, knee), 10 W (abdomen, back), and 15 W (thigh, hips, buttock). Patient satisfaction was evaluated and side effects were recorded. The laser energy counter incrementally counted the energy used; then the cumulative energy used for each treatment was recorded. Ultrasound imaging was used to control tumescent anesthesia infiltration, cannula position prior to laser emission,and postoperative fat liquefaction. Results  Five hundred thirty-four (534) laser lipolysis procedures were performed on 334 patients. Different areas were treated: hips (197), inner thighs (86), abdomen (86), knees (61), flanks (57), buttocks (28), chin (22), arms (18), back (4). Mean cumulative energy was area–dependent, ranging from a minimum of 2200 J (knee) to a maximum of 51,000 J (abdomen). Contour correction and skin retraction were observed almost immediately in most patients. There was no scarring, infection, burns, hypopigmentation, bruising, swelling, or edema. Ecchymoses were observed in almost all patients but resolved in under 1 week for 322 patients. Patient satisfaction was very high. Because laser lipolysis is an outpatient procedure, patients were able to resume normal daily activities after 24 h. Ultrasound imaging confirmed that the thermal effect generated by the laser results in melting and rupture of the collagenous and subdermal bands. Conclusion  This clinical study demonstrates that the removal of small volumes of fat with concurrent subdermal tissue contraction can be performed safely and effectively using a 980-nm diode laser. Additional benefits include excellent patient tolerance and quick recovery time. This study also confirms that enough accumulated energy must be delivered to achieve sufficient lipolysis throughout different fat layers.     

Temperature evolution on human teeth root surface after diode laser assisted endodontic treatment

The thermal rise threshold of an 810-nm semi-conductor diode laser on the root surface when used in root canals in vitro for laser assisted root canal treatment is investigated in this study. A total of 50 human single-rooted extracted teeth were included. For this study, the canals were enlarged up to an apical size of ISO#50 file. Laser irradiation was performed with six different settings. Specimens were irradiated at 0.6–1 W output power at the distal end of the fiber and about 1–1.5 W output power in the continuous mode (CW) as two groups. In the third group, 0.6–1 W output power, 10 ms pulse length (PL) and 10 ms interval duration (ID) were selected. In three other groups 1–1.5 W output power were used with different PL and ID as following: PL 10 and ID 10 ms, PL 10 and ID 20 ms and PL 20 and ID 20 ms. The total irradiation time was from 5 to 20 s per canal with a 200 m in diameter and 25 mm long tip. After laser treatment, the temperature changes at the outer root surface were registered by means of NiCr-Ni measuring sensors and a T 202 thermometer. The safe temperature threshold for applying this diode laser in root canal is considered as 7°C increase. To avoid increasing the temperature changes at the outer root surface related to this threshold, following total irradiation times were found: 0.6–1 W output power (10 ms PL/10 ms ID): 20 s (s), 1–1.5 W output power (10 ms/10 ms and 20 ms/20 ms): 15 s, 0.6–1 W output power CW and 1–1.5 W output power (20 ms PL/10 ms ID): 10 s and 1–1.5 W output power CW: 5 s. In the first three groups, 5 s irradiation and 5 s rest period avoided a temperature increase above the threshold of 7°C).     

经尿道前列腺电切术与1470 nm半导体激光汽化术治疗前列腺增生的疗效比较

【摘要】 目的 对经尿道前列腺电切术和1470 nm半导体激光汽化术治疗前列腺增生的临床疗效的比较。方法〓收集2014~2015年采用不同方法治疗前列腺增生患者的临床资料,选择1470 nm半导体激光汽化术治疗和TURP治疗的BPH患者各50例,分治疗组和对照组,2组术前临床参数比较无统计学意义(P>0.05)。对两组手术情况、随访情况及并发症发生率进行比较。结果〓采用1470 nm半导体激光汽化术治疗组显示良好临床效果,两组在手术时间、术中出血量、术后留置导尿管时间和术后住院时间的差异均有统计学学意义(P<0.05)。术后3个月随访,2组IPSS、Qmax、RUV与术前相比及组间术后相比差异均有显著性意义(P<0.05);治疗组与对照组并发症发生率分别为6%和26%,差异有统计学意义(P<0.05)。结论〓TUPR和1470 nm半导体激光汽化术均能有效的治疗前列腺增生,但1470 nm半导体激光汽化术术中出血量少,导尿管留置时间短,并发症少,安全性高,效果更好。     

755nm翠绿宝石激光联合800nm半导体激光治疗腰骶部多毛疗效分析

目的:回顾性分析755nm翠绿宝石激光联合800nm半导体激光治疗腰骶部多毛的临床疗效和安全性。方法:收集笔者医院2017年1月1日-2018年6月30日收治的100例腰骶部多毛患者病例资料,其中50例患者为单纯755nm翠绿宝石激光治疗;50例患者为755nm翠绿宝石激光联合800nm半导体激光治疗。分析两组患者的治疗效果、不良反应发生情况及对治疗效果的满意度。结果:相较于单纯755nm激光治疗,755nm翠绿宝石激光联合800nm半导体激光脱毛的有效率和治愈率显著高于755nm治疗组,两组比较有统计学意义(P<0.05);组间的VAS(视觉模拟评分法)疼痛评分比较,差异无统计学意义(P>0.05),但联合治疗组发生疼痛的次数显著低于单一治疗组(P<0.05);单纯治疗组出现2例色素沉着斑,联合治疗组无色素沉着斑出现,两组比较差异无统计学意义(P>0.05),两组均未出现色素减退斑及瘢痕;联合治疗组患者的总满意率显著高于单一治疗组(P<0.05)。结论:755nm翠绿宝石激光联合800nm半导体激光治疗腰骶部多毛临床疗效明显,安全性良好,疼痛感轻,值得广泛应用。     

Treatment of superficial cutaneous vascular lesions: experience with the KTP 532 nm laser

Whilst most facial telangiectasias respond well to short-pulse-duration pulsed dye laser therapy, studies have shown that for the treatment of larger vessels these short-duration pulses are sub-optimal. Long-pulse frequency-doubled neodymium:YAG lasers have been introduced with pulse durations ranging from 1–50 ms and treatment beam diameters of up to 4 mm. We report the results of KTP/532 nm laser treatment for superficial vascular skin lesions. The aim was to determine the efficacy of the KTP/532 nm laser in the treatment of superficial cutaneous vascular lesions at a regional dermatology centre in a 2 year retrospective analysis. Patients were referred from general dermatology clinics to a purpose-built laser facility. A test dose was performed at the initial consultation and thereafter patients were reviewed and treated at 6 week intervals. Outcome was graded into five classifications by the patient and operator independently based on photographic records: clear, marked improvement, partial response, poor response, and no change or worsening. Over the 2 year period, 204 patients with 246 diagnoses were treated [156 female; median age 41 (range 1–74) years; Fitzpatrick skin types I–III]. Equal numbers of spider angioma (102) and facial telangiectasia (102) were treated. Of those patients who completed treatment and follow up, 57/58 (98%) of spider angiomas and 44/49 (90%) of facial telangiectasia markedly improved or cleared. Satisfactory treatment outcomes, with one clearance and two partial responses, occurred in three of five patients with port-wine stain. Few patients experienced adverse effects: two declined further treatment due to pain, and a small area of minimal superficial scarring developed in one case. Two patients developed mild persistent post-inflammatory hyperpigmentation, and one subject experienced an episode of acute facial erythema, swelling and blistering after one treatment. The KTP/532 nm frequency-doubled neodymium:YAG laser is a safe and effective treatment for common superficial cutaneous vascular lesions in patients with Fitzpatrick skin types I–III.     

Clinical efficacy of semiconductor laser application as an adjunct to conventional scaling and root planing

BACKGROUND AND OBJECTIVES: The aim of the in vitro study was to examine the clinical efficacy of semiconductor laser periodontal pocket irradiation as an adjunct to conventional scaling and root planing. MATERIALS AND METHODS: Twenty-two healthy patients with a need of periodontal treatment (15 women, 7 men, mean age 45.0 +/- 10.8 years) with at least four teeth in all quadrants, were included. All of them underwent a conventional periodontal treatment including scaling and root planing. Using a split mouth design, two randomly chosen quadrants (one upper and the corresponding lower one) were subsequently treated with an 809 nm GaAlAs laser operated at a power output of 1.0 Watt using a 0.6 mm optical fiber. The teeth in the control quadrants were rinsed with saline. The clinical outcome was evaluated by means of plaque index (PI), gingival index (GI), bleeding on probing (BOP), sulcus fluid flow rate (SFFR), Periotest (PT), probing pocket depth (PPD), and clinical attachment loss (CAL) at baseline and at 3 months after treatment. A total of 492 teeth in both groups were evaluated and differences between the laser and the control teeth were analyzed using the Wilcoxon test (P < 0.05). RESULTS: Teeth treated with the laser revealed a significantly higher reduction in tooth mobility, pocket depth, and clinical attachment loss. Twelve percent of the teeth in the laser group showed an attachment gain of 3 mm or more, compared to 7% in the control group. An attachment gain of 2-3 mm was found in 24% of the teeth in the laser group and 18% in the control group. No significant group differences, however, could be detected for the plaque index, gingival index, bleeding on probing, and the sulcus fluid flow rate. CONCLUSIONS: The higher reduction in tooth mobility and probing depths is probably not predominantly related to bacterial reduction in the periodontal pockets but to the de-epithelization of the periodontal pockets leading to an enhanced connective tissue attachment. The application of the diode laser in the treatment of inflammatory periodontitis at the irradiation parameters described above is a safe clinical procedure and can be recommended as an adjunct to conventional scaling and root planing.