Wettability Gradient-Induced Diode: MXene-Engineered Membrane for Passive-Evaporative Cooling

Thermoregulatory textiles, leveraging high-emissivity structural materials, have arisen as a promising candidate for personal cooling management; however, their advancement has been hindered by the underperformed water moisture transportation capacity, which impacts on their thermophysiological comfort. Herein, we designed a wettability-gradient-induced-diode (WGID) membrane achieving by MXene-engineered electrospun technology, which could facilitate heat dissipation and moisture-wicking transportation. As a result, the obtained WGID membrane could obtain a cooling temperature of 1.5 °C in the "dry" state, and 7.1 °C in the "wet" state, which was ascribed to its high emissivity of 96.40% in the MIR range, superior thermal conductivity of 0.3349 W m-1 K-1 (based on radiation- and conduction-controlled mechanisms), and unidirectional moisture transportation property. The proposed design offers an approach for meticulously engineering electrospun membranes with enhanced heat dissipation and moisture transportation, thereby paving the way for developing more efficient and comfortable thermoregulatory textiles in a high-humidity microenvironment.

In vivo dose measurements for tangential field-in-field ultra-hypofractionated breast radiotherapy

INTRODUCTION

Ultra-hypofractionated radiotherapy (UHF-RT) mandates more accuracy in each part of the treatment cycle to maximize cure rates and minimize toxicities. In vivo dosimetry is a direct method for verifying overall treatment accuracy. This study evaluated uncertainties in the delivered dose of Hypofractionated (HF) and UHF Whole Breast Irradiation (WBI) and to analyze the accuracy of the workflow to pave the way for a wide-scale use of UHF-RT.

METHODS

Thirty-three breast cancer cases, including 16 HF-WBI and 17 UHF-WBI were treated with 3D conformal Radiotherapy (3D-CRT), where 79 fields were analyzed for dose verification. The measurement point was set at the beam entrance (1.5 cm depth). The expected dose at Dmax was calculated via TPS. Before in vivo measurements, diode detectors were tested and calibrated. We developed initial validation measurements for UHF-RT on an anthropomorphic breast phantom for the first time.

RESULTS

For RANDO phantom, the percentage difference between measured and calculated doses showed an average of -0.52 ± 5.4%, in addition to an excellent dose reproducibility within 0.6%. The overall in vivo measurements for studied cases showed that 83.5% of the measured doses were within ±5% and only 1.8% of the measured doses were greater than ±10% of the calculated doses. The percentage accuracy was slightly larger for UHF cohort (84.2%) compared to HF cohort (83.2%). The maximum percentage difference between them was less than 1%.

CONCLUSION

Breast in vivo dosimetry is an adequate tool for treatment verification that improves the accuracy of the treatment cycle. UHF-RT may contribute in reducing the long waiting lists, increasing patient convenience, and saving the available resources for breast cancer patients.

Evaluation of the Effect of Phosphoric Acid or Er: YAG Laser on the Shear Bond Strength of Orthodontic Brackets to Enamel Surfaces Followed by 980-Laser Assisted Bleaching: An In Vitro Study

Introduction: The residual oxygen remained on tooth surface after bleaching may interfere with adhesion of brackets to enamel surface. This study aimed to evaluate the influence of phosphoric acid and Er: YAG laser as an etching technique on the shear bond strength (SBS) of orthodontic brackets to enamel surfaces after 980-laser-assisted bleaching. Methods: A total of 84 human premolars were recruited in the present study. Samples were divided into 6 groups including conventional bleaching with conventional etching, conventional bleaching with Er: YAG laser etching, laser-assisted bleaching with conventional etching, and Laser-assisted bleaching with Er: YAG laser etching, without bleaching with traditional etching, and without bleaching+Er: YAG laser etching. Following thermocycling, the debonding of brackets was conducted using a universal testing machine. Scanning electron microscope (SEM) microscope evaluation and adhesive remnant index (ARI) scores were assessed. The comparison of SBS values between groups was carried out by means of a one-way analysis of variance, followed by post-hoc tests. Results: The non-bleaching with conventional etching group showed the highest SBS mean value (23.45±5.16 MPa), whereas the conventional bleaching with conventional etching group represented the lowest SBS mean value (8.8±3.83 MPa). In all groups, the most common type of failure was classified as either score 1 or score 2. No significant difference was observed in terms of SBS mean between the groups (P=0.165); however, the average SBS of bleached teeth was significantly lower, compared to the non-bleached group (P=0.000). Honeycomb structure and porosity were observed following Er: YAG laser etching on the tooth surface. Conclusion: Increased bond strength of brackets was observed in bleached teeth following Er: YAG laser etching. Therefore, if necessary, bond the brackets on the same day of bleaching will be done, the application of Er:YAG laser as etching technique will can be recommended.

Assessment of clinical outcomes and patient response to gingival depigmentation using a scalpel, ceramic bur, and diode laser 980 nm

OBJECTIVE

This research compares the clinical outcomes of gingival depigmentation procedures with conventional scalpel, ceramic trimmer bur, and diode laser techniques.

MATERIALS AND METHODS

Twenty-four individuals with physiologic gingival hyperpigmentation received random allocation to one of three treatment groups: scalpel, ceramic bur, or diode laser. Pain score, operation time, bleeding index, degree of epithelialization, wound healing, Dummett-Gupta Oral Pigmentation Index (DOPI), and Takashi Index score changes were all investigated at different time points.

RESULTS

At 12-h follow-up, significant variations in pain scores were seen between the laser and scalpel groups (p = 0.003) but not between the laser and ceramic bur groups. The diode laser group completed the procedure significantly quicker than the scalpel and ceramic bur groups (p = 0.004 and p = 0.001, respectively). The ceramic trimmer bur and diode laser groups showed significantly less bleeding tendency than the scalpel group. Wound healing and the degree of epithelialization were similar in all groups. DOPI and Takashi indices significantly decreased compared to baseline in all groups, with no significant difference recorded between all groups.

CONCLUSION

While diode lasers are a safe and effective treatment option for gingival hyperpigmentation, providing optimal aesthetics with reduced discomfort to patients, a ceramic trimmer bur can also be used as a simple and affordable alternative to a laser in gingival depigmentation procedures.

CLINICAL RELEVANCE

Gingival hyperpigmentation is a major aesthetic issue for many individuals. Laser and ceramic trimmer bur treatments produce equivalent aesthetic outcomes for gingival hyperpigmentation.

Photobiomodulation therapy with light-emitting diode in stimulating adipose tissue mitochondria

Low-level laser therapy (LLLT) is known for its ability to induce a photochemical process, primarily targeting mitochondria, a process referred to as photobiomodulation (PBM). Recently, its use has been attributed as an adjunct in obesity treatment, to stimulate lipolysis and apoptosis. However, the pathway of stimulation remains uncertain. Thus, the objective of this study was to understand whether mitochondrial stimulation occurs in adipose tissue cells after PBM therapy, which could lead to the processes of lipolysis and apoptosis. A non-randomized clinical trial was conducted using a split abdomen design in obese women who received red and infrared LED photobiomodulation therapy (PBMT). The patients underwent bariatric surgery, and adipose tissue samples were collected for immunohistochemical analysis with primary mitochondrial antibodies. Adipose tissue samples subjected to LED intervention exhibited positivity in mitochondrial antibodies for cAMP, DRP1, FAS, FIS1, MFN2, and OPA1 (p<0.001) compared to the control group. In conclusion, we observed that PBMT was capable of generating mitochondrial stimulation in adipose tissue cells, as evidenced by the positive antibody signals. This finding suggests that mitochondrial stimulation could be the mechanism and action underlying adipose tissue lipolysis and apoptosis.

Application of wireless energy transmission technology into central venous ports with light-emitting diodes

Implantable central venous (CV) ports are widely used for chemotherapy and parenteral nutrition. Generally, CV ports are used safely; however, some patients suffer from drug leakage around the port septum due to mispuncture. Therefore, we developed a CV port that is visible under the skin. We created a prototype of a CV port using a 3D printer. Three red light-emitting diodes (LEDs) were attached around the septum that made the puncture site visible by applying wireless energy transmission technology using electromagnetic resonance. The CV port was implanted under the skin of pork rose meat. The thickness of the skin of pork loin was measured. Fifteen medical doctors participated in the study to visually confirm the lighted CV port. The visibility of the center of the septum with and without lights was scored 0 as non-diagnostic; 1, slightly visible; 2, well visible; and 3, obviously visible. The visibility with or without lights was assessed. The relationship between the years of experience and the visibility score was assessed. The Wilcoxon test was used for statistical analysis. LEDs were easily transmitted through the skin of pork rose meat. The median visibility scores with or without lights were 2 (range, 1-3) and 3 (range, 1-3), respectively (p = 0.005). No significant relationship was found between experience and visibility score (p = 0.289). CV ports with LEDs can be easily recognized compared with those without LEDs. This technique may contribute to medical safety by improving its visibility to avoid mispuncture.

Diode Laser in the Management of Foliate Papillitis - Two Case Reports

The human tongue consists of various kinds of papillae which form its characteristic morphology. Among these papillae, the foliate papillae may become enlarged and inflamed causing a condition called as foliate papillitis. The treatment of this disease includes relieving all causes of trauma such as sharp teeth, ill-fitting dentures, etc., to the region. However, for several patients, the symptoms of foliate papillitis remain even after the conservative treatment is done. For two of these patients, we have used IMDSL dental diode laser of 980 nm to ablate the enlarged foliate papillae to relieve the symptoms of pain. Both the patients were recalled after one month during which time they were free of symptoms with total healing of the ablated site. One year later, during follow-up, both the patients remained symptom free. We believe this is the first time that diode laser has been used for the treatment of foliate papillitis.

Comparison of the Effectiveness of CO2 and Diode Lasers for Gingival Melanin Depigmentation: A Randomized Clinical Trial

Introduction: Gingival hyperpigmentation is an esthetic concern for some individuals. This study compared the effectiveness of CO2 and diode lasers for gingival depigmentation. Methods: This randomized, split-mouth, clinical trial consisted of 12 patients with the chief complaint of hyperpigmented gingival areas. The upper right and left anterior segments and the mandibular anterior segment were randomly allocated to one of the treatment groups. The segments in group 1 underwent gingival depigmentation with a diode laser (810 nm) at 6 W and pulsed mode, whereas group 2 was ablated with a diode laser at 3 W and continuous mode. The removal of gingival pigments in group 3 was contemplated with a CO2 laser (10600 nm, 3 W, continuous mode). The operation chair time, bleeding during the procedure and post-operative pain were recorded. The gingival color and esthetic appearance were measured before the operation and at 1 week and 6 months later. Results: There was no significant difference in the bleeding scores, pain level, and color alteration values between the groups (P>0.05). The operation chair time was significantly shorter when the diode laser was applied at pulsed mode (P<0.05). The segments treated with the diode laser (pulsed or continuous mode) showed a higher esthetic appearance at the 6-month follow-up compared to those ablated with the CO2 laser (P<0.05). Conclusions: Higher esthetic appearance is expected when using the diode laser for gingival depigmentation compared to the CO2 laser. The application of the diode laser at pulsed mode could be recommended for gingival depigmentation, as it produced pleasing esthetic outcomes at reduced chair time.

Effectiveness of an 810-nm Diode Laser in Addition to Non-surgical Periodontal Therapy in Patients With Chronic Periodontitis: A Randomized Single-Blind Clinical Trial

Introduction: This study evaluated the effectiveness of an 810-nm diode laser as an adjunct to scaling and root planning (SRP) in improving periodontal parameters in patients with chronic periodontitis. Methods: This randomized clinical trial consisted of 36 patients (16 females and 20 males) with chronic periodontitis and pocket depths of 4-6 mm. The quadrants were randomly divided into two sides; one side of each patient was selected as the laser group (SRP + laser) and the other side served as the control group (SRP alone). An 810-nm diode laser was applied in the laser side to remove the outer gingival epithelium (1.5 W, CW) as well as the inner epithelium of the periodontal pockets (1 W, CW). The clinical parameters including bleeding on probing (BOP), probing depth (PD), plaque index (PI), and clinical attachment level (CAL) were measured at baseline and 6 and 18 weeks after therapy. Results: In both groups, there was a significant improvement in BOP, PD, PI and CAL over the course of the experiment (P < 0.001). Significantly lower BOP was found in the SRP + laser group than the SRP alone group after 6 and 18 weeks of intervention (P < 0.05). The difference in other parameters was not significant between the two groups, neither at 6 nor at 18 weeks after the treatment (P > 0.05). Conclusion: Within the limitations of this study, the association of the diode laser with standard non-surgical periodontal therapy (SRP) provided minimal additional benefits for patients with moderate chronic periodontitis.

Erbium, chromium-doped: yttrium, scandium, gallium, garnet and diode lasers in the treatment of peri-implantitis: clinical and biochemical outcomes in a randomized-controlled clinical trial

This study aims to evaluate the effects of 940 nm diode laser and 2780 nm erbium, chromium-doped: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) laser used in addition to mechanical therapy in the non-surgical treatment of peri-implantitis on clinical parameters and matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels in the peri-implant crevicular fluid. A total of 50 patients with peri-implantitis were randomized into three groups to receive peri-implant treatment. The control group (n = 17) only received conventional non-surgical mechanical therapy. The trial groups [(diode group (n = 16) and Er,Cr:YSGG group (n = 17)] received dental laser in addition to mechanical therapy. Gingival index (GI), plaque index (PI), bleeding on probing, probing depth (PD), MMP-9, and TIMP-1 levels were assessed at baseline (T0) and at 6 months after treatment (T1). The GI, PI, and PD significantly decreased in all groups at T1, compared to T0 (p < 0.05). The decrease in the PD was similar between the control and diode groups with Er,Cr:YSGG providing more reduction (1.16 ± 0.64 mm) than either method (p = 0.032). A significant intra-group decrease in MMP-9 level was only observed in the Er,Cr:YSGG group (p = 0.009). The decrease in TIMP-1 level from T0 to T1 was similar between the control and the diode groups (p > 0.05) and it was significantly lower than the decrease in the Er,Cr:YSGG group (p < 0.05). Addition of diode laser to non-surgical mechanical therapy does not provide any additional benefit for treatment outcomes. The Er,Cr:YSGG laser seems to be more efficient both at clinical and molecular levels. ClinicalTrials, ID: NCT04730687. Registered 13 April 2021. Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04730687.

Efficacy of photobiomodulation in the management of tinnitus: A systematic review of randomized control trials

There is a controversy in regards to the efficacy of photobiomodulation (PBM) in the management of tinnitus. The aim was to systematically review randomized controlled trials (RCTs) that assessed the efficacy of PBM (low-level laser therapy) in the management of tinnitus. The focused question was "Is PBM effective in the management of tinnitus?". Indexed databases were searched up to and including June 2020 using different combinations of the following key words: (a) laser; (b) diode; (c) low-level laser therapy; (d) photobiomodulation; (e) tinnitus; (f) medium-level laser; (g) photo-biomodulation; and (h) low-power laser; and RCTs performed on humans were included. Letters to the editor; case reports/series; commentaries; experimental studies and historic reviews were excluded. The risk of bias was assessed using the modified cochrane collaboration tool. The format of the current systematic review was personalized to summarize the appropriate information. Ten RCTs (2 single-blinded and 8 double-blinded) were included. One study reported 30% and 100% resolution of tinnitus using diode and Neodymium-doped Yttrium Aluminum Garnet lasers; respectively. One study reported that PBM was effective in relieving tinnitus for up to 3 months. Eight studies reported that PBM was ineffective in the management of chronic tinnitus. The risk of bias was high; medium and low in 4; 5 and 1 studies; respectively. The effectiveness of PBM in the management of tinnitus remains debatable. Further power-adjusted and well-designed RCTs with long-term follow-up are needed.

Efficacy of Photobiomodulation Therapy for Orthodontic Pain Control Following the Placement of Elastomeric Separators: A Randomized Clinical Trial

Introduction: Controlling pain in orthodontic patients has gained special attention. This study assessed the efficacy of photobiomodulation therapy (PBMT) for pain control following the placement of elastomeric separators. Methods: This split-mouth single-blind randomized clinical trial evaluated 30 orthodontic patients who required posterior elastomeric separators. The two maxillary quadrants were randomized into the laser and control groups. In the laser quadrant, an 808 nm diode laser (400 mW, 15.60 J/cm² , 11 seconds, continuous-wave, contact mode) was irradiated to the cervical third of the maxillary first molar roots 24 hours prior to the placement of separators. The control quadrant received placebo radiation by a light-curing unit. The patients received the second laser cycle right before the placement of separators 24 hours later. The level of self-perceived pain was recorded at 0, 2, 6, 24, and 72 hours and 5 days after the intervention in the laser and control quadrants using a visual analog scale (VAS). Data were analyzed using the analysis of variance (ANOVA) and paired-samples t test. Results: The trend of change in the pain score was similar in both groups. The pain score was significantly lower in the laser group than the control group at all-time points (P <0.05) except at time 0. The pain score increased in the first 6 hours and reached its maximum level in 24 hours in both groups. Conclusion: PBMT by an 808 nm diode laser can effectively decrease pain following the placement of elastomeric separators.

Comparison of laser power output from the fiber tip during endovenous laser ablation against displayed power and the "first treatment" effect

OBJECTIVE

International guidelines recommend endovenous laser ablation as one of the first-line treatments for truncal venous reflux associated with varicose veins. Clinicians use linear endovenous energy density to measure the energy used during treatment. The aim of this study was to investigate the power output from the fiber tip and to see if this changed with use.

METHODS

We placed 15 mL of water in a thermally insulated 25-mL beaker. Two thermocouples were placed equidistantly adjacent to the laser fiber tip. A 1470-nm laser was fired at 5W for 2 minutes and the temperature change was measured. Three fibers were used on different days to allow the laser to cool for 24 hours between fibers. Each fiber was tested three times in a row. We also tested the "first treatment" effect by comparing the power output when the fiber was fired immediately after the laser was switched on, compared with treatments when the laser had been switched on for 1 hour. To assess whether this was due to the console being "cold" on the first firing of the day, we repeated the experiment having switched on the laser console 1 hour before firing to "prewarm" the console. However, the diode was not fired during this hour. To measure fiber degradation, three runs of the experiment were performed successively before firing the laser continuously for 20 minutes, then three more runs were conducted, resulting in delivery of approximately 10,000 J.

RESULTS

The actual power output seemed to be lower than the console suggested. The power output from the first fiber used in a succession of three with the same laser had a significantly lower power output than the following two runs (P = .0004 and P < .0001, respectively). When the laser was prewarmed for 1 hour without firing, no change in this output pattern was noted (P = .293). Fiber degradation was not found in any of the fibers that were tested within the maximum recommended for the fiber (10,000 J).

CONCLUSIONS

The first use of a fiber in a treatment session has a significantly lower power output from the treatment tip than subsequent uses, even if the machine is prewarmed and the console displays the same power for each. The authors believe that this phenomenon is due to the diode being less efficient when first used after switching it on. Clinicians need to be aware that the true power output at the fiber tip may not be as indicated by the console display and may be variable during a treatment session.

Safety and Efficacy of 980nm Diode Laser for Brain Tumor Microsurgery-A Pioneer Case Series

BACKGROUND

Quality of life is essential for oncologic patients. Several tools are available to improve microsurgery and reduce morbidity. Diode laser is a precise and useful technology for microsurgery. The goal of this pioneer case series is to describe the oncologic use of the 980nm diode laser and the qualitative variables analyzed. Besides, review the current literature about lasers in neurosurgery.

METHODS

A longitudinal prospective study described patients with meningioma or glioma submitted to neurosurgical laser-assisted procedures. Also, we performed a review in medical databases using the terms "diode laser" and "neurosurgery."

RESULTS

No paper described the use of a diode laser in neurooncology. The 980nm diode laser was used in 15 patients. The device is thin, silent, and easy to handle. Excellent hemostasis was observed, especially in skull base meningiomas. Also, it was easy and fast to delimit tumor from normal brain tissue without damage to surrounding parenchyma. No postoperative complications occurred.

CONCLUSIONS

The diode laser is a useful tool for brain tumor surgery, particularly concerning hemostasis. Surgical site coagulation is effective without damage to adjacent structures, especially in gliomas near eloquent regions. We consider this technique a suitable adjuvant resource for brain tumor surgeries to provide an excellent hemostasis and help cut and vaporize a lesion.

Hydrogen peroxide penetration into the pulp chamber during conventional in-office bleaching and diode laser-assisted bleaching with three different wavelengths

BACKGROUND AND AIMS

Penetration of hydrogen peroxide into the pulp chamber and subsequent tooth hypersensitivity is a common concern in dental bleaching. The aim of this study was to assess the penetration of hydrogen peroxide (H2O2) into the pulp chamber in diode-laser activated bleaching with different laser wavelengths.

MATERIALS AND METHODS

Fifty extracted human maxillary anterior teeth were collected and divided into five groups(n = 10). Group 1: conventional in-office bleaching using Opalescence Boost gel. Group 2: Bleaching with Biolase Laser White 20 gel activated by 980 nm diode laser. Group 3: Bleaching with Biolase Laser White 20 gel activated by 810 nm diode laser. Group 4: Bleaching with Biolase Laser White 20 gel activated by 940 nm diode laser. Group 5: No bleaching control group.After bleaching, the solution into the pulp chamber was collected and analyzed using a spectrophotometer. The recorded data were compared with a standard sample and the results were analyzed and compared using one-way ANOVA and Tukey's HSD tests.

RESULTS

In all bleached groups, H2O2 had infiltrated into the pulp chamber. The highest level of penetration was noted in group 2 (2.32 ± 0.25 µg), while the lowest level was noted in group 3 (1.85 ± 0.33 µg). The difference in this regard was significant between groups 2 and 3 (P = 0.024), but the differences between other groups were not statistically significant (P ≥ 0.42).

CONCLUSION

Considering the results of this study, it can be stated that hydroge peroxide penetration in to pulp chamber in diode laser activation of bleaching agent according to manufactures instruction is not higher than in-office bleaching. The wavelength of diode laser had significant effect on penetration of hydrogen peroxide into pulp chamber.

A novel quality assurance system for eye plaque brachytherapy

Eye Plaque brachytherapy pre-treatment quality assurance (QA) conducted clinically involves an activity verification of individual seeds via well chamber and does not include a physical measurement of dose-rate of the final assembly. A novel spectroscopic, dose-rate detection system, was evaluated for pre-treatment QA of eye plaque brachytherapy. The system includes a water phantom with sterility management. The system was calibrated using a known-activity I-125 seed, measured at 1 cm in water along the radial axis, compared to TG-43 U1 calculations and verified over a number of distances. A depth dose curve was acquired for a clinical, mixed activity eye plaque and two 'error' plaques. The probe was stepped from a water equivalent source to a detector distance (SDD) of 2.5 to 12 mm along the plaque central axis. The latter measurements aimed to characterise the sensitivity of the system. The calculated and measured single-seed dose-rates agreed to within 0.5 cGy/h from a SDD of 3 mm and above. The clinical plaque showed agreement between measured and treatment planning system (TPS) calculated dose-rates within 2%. Sensitivity testing resulted in a maximum deviation from TPS data of 18%, therefore was able to detect the presence of packing errors. The dose-rate detection system was successfully evaluated for verification of I-125 based eye plaques without compromising sterility, allowing for quick pre-treatment, dose-rate verification of patient-ready plaques. Its agreement with TPS data for the unmodified plaque and its deviation when introducing errors confirms the approach suggested is a viable QA tool.

Effects of different settings for 940 nm diode laser on expanded suture in rats

OBJECTIVES

To evaluate the effects of the Indium Gallium Arsenide Phosphoride (InGaAsP) diode laser at different energy levels on orthopedically expanded midpalatal sutures of rats.

MATERIALS AND METHODS

Eighty Wistar rats were randomly divided into four groups: a control group and low-, moderate-, and high-level laser groups with amounts of energy irradiated at 0 J, 18 J, 42 J, and 60 J, respectively. Each group was divided into two subgroups (n = 10) according to the schedule of sacrifice (7 and 21 days). Laser application (940 ± 10 nm, 0.1 W) was completed twice weekly until sacrifice. The number of osteoblasts (OB), osteocytes (OC), and vessels (V); area of connective tissue (CT); inflammation (IN); and newly formed bone (NB); as well as the ratio of newly formed bone to the total bone area (N/T) were evaluated statistically at a significance level of P < .05.

RESULTS

For the low-level laser group, OB, NB, and N/T were significantly higher, and CT was lower, on both the 7th and 21st days. The amount of OC was significantly higher in the low-level laser group compared with the control group on the 7th day and the control and high-level laser groups on the 21st day. The IN was significantly higher for the high-level group on the 21st day compared with other groups. Both the moderate-level and high-level laser groups possessed fewer vessels than the low-level laser group on the 21st day.

CONCLUSIONS

The InGaAsP laser at the low dosage induced a favorable effect on bone formation in the orthopedically expanded midpalatal suture of rats.

Overview of Lasers for Flow Cytometry

Lasers are critical elements of all flow cytometers. Instrument capabilities are dictated by the wavelengths and characteristics of its laser sources. In this chapter, we review the lasers available for flow cytometry, and provide guidance in choosing laser wavelengths and characteristics to best match the analytical needs of biomedical research laboratories.

Detection of Toxic Heavy Metal, Co(II) Trace via Voltammetry with Semiconductor Microelectrodes

The cobalt (Co(II)) ion is a main component of alloys and considered to be carcinogenic, especially due to the carcinogenic and toxicological effects in the aquatic environment. The toxic trace of the Co(II) detection was conducted using the infrared photodiode electrode (IPDE) using a working electrode, via the cyclic and square-wave anodic stripping voltammetry. The results indicated a sensitive oxidation peak current of Co(II) on the IPDE. Under the optimal conditions, the common-type glassy carbon, the metal platinum, the carbon paste, and the carbon fiber microelectrode were compared with the IPDE in the electrolyte using the standard Co(II). The IPDE was found to be far superior to the others.

Diode Laser Ear Piercing: A Novel Technique

Earlobe piercing is a common office room procedure done by a plastic surgeon. Various methods of ear piercing have been described. In this article, we describe a novel method of laser ear piercing using the diode laser. An 18-year-old female patient underwent an ear piercing using a diode laser with a power of 2.0 W in continuous mode after topical local anaesthetic and pre-cooling. The diode laser was fast, safe, easy to use and highly effective way of ear piercing. The advantages we noticed while using the diode laser over conventional methods were more precision, minimal trauma with less chances of hypertrophy and keloids, no bleeding with coagulation effect of laser, less time taken compared to conventional method and less chance of infection due to thermal heat effect of laser.

450 nm Blue Laser and Oral Surgery: Preliminary ex vivo Study

INTRODUCTION

Dental diode lasers were started to be used at the end of the 1990s and were shown to possess several important characteristics, such as small size and low cost, as well as the advantage of optic fibers delivering system. Although only two wavelengths (810 and 980 nm) had been the most used dental diode lasers, a wavelength emitting in the blue portion of the spectrum has recently been proposed.

AIM

The aim of this ex vivo study was to compare the effectiveness of five different fiber-delivered laser wavelengths (450, 532, 808, 1064, and 1340 nm) in the oral soft tissue ablation.

MATERIALS AND METHODS

Specimens were surgically collected from the dorsal surface of four bovine tongues and, while deep thermal increase was measured by two thermocouples at 0.5 and 2 mm depth, surface temperature was recorded by an infrared thermometer. Subsequently, specimens were fixed in 10% buffered formalin solution, cut into slices, and embedded in paraffin blocks, and a pathologist made a morphological analysis by optic microscope assigning a score based on the quality of the cut and tissue damage.

RESULTS

The analysis showed the best quality of the cut and the lowest temperature increase on the specimens obtained with the shortest laser wavelength (450 nm).

CONCLUSION

Even considering this as preliminary study, the use of 450 nm blue diode laser in oral surgery may be suggested to the clinician in their daily practice.

CLINICAL SIGNIFICANCE

This study opens a new perspective in oral surgery. Blue diode laser has demonstrated a good quality of the cut with a low energy causing a minimal thermal damage to the tissue, promising a better comfort to patients.

Laser and light-based treatments of venous lakes: a literature review

Venous lake is a benign vascular malformation commonly seen in elderly patients, typically arising in sun-exposed areas of the body. Patients often seek treatment to prevent recurrent bleeding or because they find the lesion cosmetically unacceptable. Venous lake may negatively affect quality of life, due to the cosmetic disfigurement it can create and the resulting psychological distress. Traditional treatments, such as surgical excision, cryosurgery, sclerotherapy, and electrocoagulation, result in varying degrees of success and can cause discomfort. Laser- and light-based treatment modalities may offer a safe and effective alternative, as numerous studies have shown their benefit in the treatment of venous lakes, particularly with the long-pulsed 1064-nm neodymium-doped yttrium aluminum garnet (Nd:YAG). Although various types of lasers and lights have been studied, there remains a lack of general consensus as to which one is the superior laser modality. Further studies that establish standardized protocols to compare the results of using different types of laser treatments are warranted.

405 nm diode laser, halogen lamp and LED device comparison in dental composites cure: an "in vitro" experimental trial

BACKGROUND AND AIMS

A 405 nm diode laser is indicated for composite materials polymerizing, thanks to the recent evolution in their compositions, absorbing in blue part of the spectrum. The purpose of this research was to evaluate its performance on two different kinds of composite resins.

MATERIALS AND METHODS

Two different composites were polymerized with a traditional halogen lamp, a LED device and a 405 nm diode laser. The depth of the cure, the volumetric shrinkage, and the degree of the conversion (DC%) of the double bond during the curing process were measured. One-way ANOVA test, Kruskal-Wallis tests, and Dunn comparison tests were used for statistic analysis.

RESULTS

Regarding the depth of polymerization, the laser had the worst performance on one composite while on the other, no significant difference with the other devices was observed. The volumetric shrinkage showed that laser produced the lowest change in both of the composites. The DC% measure confirmed these findings.

CONCLUSIONS

Based on the results of this preliminary study, it is not possible to recommend the 405 nm diode laser for the polymerization of dental composites.

The efficacy of laser-assisted in-office bleaching and home bleaching on sound and demineralized enamel

AIMS

This study investigated the effectiveness of laser-assisted in-office bleaching and home-bleaching in sound and demineralized enamel.

MATERIALS AND METHODS

The sample consisted of 120 freshly-extracted bovine incisors. Half of the specimens were stored in a demineralizing solution to induce white spot lesions. Following exposure to a tea solution for 7.5 days, the specimens were randomly assigned to 4 groups of 30 according to the type of enamel and the bleaching procedure employed. Groups 1 and 2 consisted of demineralized teeth subjected to in-office bleaching and home bleaching, whereas in groups 3 and 4, sound teeth were subjected to in-office and home bleaching, respectively. A diode laser (810 nm, 2 W, continuous wave, four times for 15 seconds each) was employed for assisting the in-office process. The color of the specimens was measured before (T1) and after (T2) staining and during (T3) and after (T4) the bleaching procedures using a spectrophotometer. The color change (ΔE) between different treatments stages was compared among the groups.

RESULTS

There were significant differences in the color change between T2 and T3 (ΔE T2-T3) and T2 and T4 (ΔE T2-T4) stages among the study groups (p<0.05). Pairwise comparison by Duncan test revealed that both ΔET2-T3 and ΔET2-T4 were significantly greater in demineralized teeth submitted to laser-assisted in-office bleaching (group 1) as compared to the other groups (P< 0.05).

CONCLUSION

Laser-assisted in-office bleaching could provide faster and greater whitening effect than home bleaching on stained demineralized enamel, but both procedures produced comparable results on sound teeth.

Four different diode lasers comparison on soft tissues surgery: a preliminary ex vivo study

Objectives: The introduction of diode lasers in dentistry had several advantages, principally consisting on the reduced size, reduced cost and possibility to beam delivering by optical fibbers. Up today only the wavelengths around 810 and 980 nm were the most utilized in oral surgery but recently more different lasers had been proposed. The aim of this study was to compare the efficacy of four diode laser wavelengths (810, 980, 1470 and 1950 nm) for the ablation of soft tissues. Material and methods: Specimens were surgically collected from the dorsal surface of four bovine tongues and irradiated by four different diode wavelengths. Thermal increase was measured by two thermocouples, the first at a depth of 0.5 mm, and the second at a depth of 2 mm. Initial and final surface temperatures were recorded by IR thermometer. Epithelial changes, connective tissue modifications, presence of vascular modification and incision morphology were histologically evaluated by two blind pathologists. Results: The time necessary to perform the excision varied between 271 seconds (808 nm, 2W) and 112 seconds (1950 nm, 4W). Temperature increase superficial level varied from 16.3° (980 nm, 4W) and 9.2° (1950 nm, 2 W). The most significant deep temperature increase was recorded by 980 nm, 4 W (17.3°) and the lowest by 1950 nm, 2 W (9.7°). The width of epithelial tissue injuries varied between 74 pm from 1950 nm diode laser at 2 W to 540 pm for 1470 nm diode laser at 4 W. Conclusion: The quality of incision was better and the width of overall tissue injuries was minor in the specimens obtained with higher wavelength (1950 nm) at lower power (2W).

Evolution of the role of phototherapy during endodontic decontamination

A microbe free root canal space before obturation leads to higher success rate and conventional chemo-mechanical debridement might not achieve this goal completely. First trials of laser in dentistry started from surgical intervention on caries and bones of oral cavity and extended to prepare cavities and even shaping root canals. Afterward lasers were implicated soon into direct debridement of root canal space. Anyhow failure of laser to remove debris totally from root canal space is demonstrated recently, additionally it might lead to damages to surrounding tissues or inorganic material of root canal if be used without precaution. Nowadays the theory of light assisted protocols became another start point for laser in endodontics. Laser has been introduced as an adjuvant to conventional debridement of root canals. We used Medline search engine to collect scientific publications to edit this review article in purpose of revealing the evolution of laser position from an ultimate cleaning methodology to an adjuvant to conventional root canal disinfection protocols.

[Evaluation of the efficacy of diode laser endocyclophotocoagulation combined with cataract surgery in glaucoma]

INTRODUCTION

Surgical techniques, which reduce the secretion of aqueous humor are underutilized in the surgical management of glaucoma; the diode laser coupled to an endoscope, endocyclophotocoagulation (ECP), is an emerging technology in the treatment of glaucoma. Indeed, thanks to its direct, focal and controllable approach to diode laser treatment of the ciliary processes, ECP renders this a safer technique compared to transscleral diode laser. We present preliminary results and an evaluation of the efficacy of ECP combined with cataract surgery performed at the Al Bassar clinic in Mohammedia, Morocco.

PATIENTS AND METHODS

We conducted a retrospective study on a series of 82 patients who underwent combined surgery: diode laser endocyclophotocoagulation and cataract for treatment of glaucoma during the period from December 2012 to July 2013. For this study, we recorded: age and gender of the patients, number and power of diode laser spots, pre- and postoperative intraocular pressure (IOP), and the number of anti-glaucoma treatments prescribed pre- and postoperatively (3 months minimum). Technically, a 20-gauge endo-ocular probe is inserted through the corneal incision used for phacoemulsification. The probe is equipped with a light source, a camera and a pulsed 810 nm laser beam; it is connected to an Endo-optiks type generator, which allows for direct visualization of the ciliary processes and their precise treatment.

RESULTS

The surgical procedure is both simple and quick. Postoperative follow-up is unchanged from the management of cataract extraction by phacoemulsification. The average age in our series was 69.5 years (range 33-81 years), mean follow-up was 5.7 months. The reduction in intraocular pressure was 28.5%. In 40% of patients, a significant reduction in medications was noted, and in 20%, a total suspension of anti-glaucoma medications. No serious complications were noted in our series.

DISCUSSION

This technique can perfectly fit into the medical, natural and/or surgical armamentarium medical, physical, surgical to halt progression of glaucomatous disease. The IOP lowering obtained by this combined surgery is significantly greater than that obtained after phacoemulsification alone in open-angle glaucoma. It can accommodate many situations for which conventional surgery has limitations. In addition, this technique has the advantage of preserving the bulbar conjunctiva for any subsequent glaucoma surgeries.

CONCLUSION

Our preliminary results are very satisfactory. This combined technique is simple, safe and effective. This allows broadening of its indications to include moderate glaucoma, stabilized or not, in addition to refractory glaucoma. Also, from an economic point of view, the gain for the patient is significant. Of course, longer-term follow-up is required to confirm these results.

High sensitivity Schottky junction diode based on monolithically grown aligned polypyrrole nanofibers: Broad range detection of m-dihydroxybenzene

Aligned p-type polypyrrole (PPy) nanofibers (NFs) thin film was grown on n-type silicon (100) substrate by an electrochemical technique to fabricate Schottky junction diode for the efficient detection of m-dihydroxybenzene chemical. The highly dense and well aligned PPy NFs with the average diameter (∼150-200 nm) were grown on n-type Si substrate. The formation of aligned PPy NFs was confirmed by elucidating the structural, compositional and the optical properties. The electrochemical behavior of the fabricated Pt/p-aligned PPy NFs/n-silicon Schottky junction diode was evaluated by cyclovoltametry (CV) and current (I)-voltage (V) measurements with the variation of m-dihydroxybenzene concentration in the phosphate buffer solution (PBS). The fabricated Pt/p-aligned PPy NFs/n-silicon Schottky junction diode exhibited the rectifying behavior of I-V curve with the addition of m-dihydroxybenzene chemical, while a weak rectifying I-V behavior was observed without m-dihydroxybenzene chemical. This non-linear I-V behavior suggested the formation of Schottky barrier at the interface of Pt layer and p-aligned PPy NFs/n-silicon thin film layer. By analyzing the I-V characteristics, the fabricated Pt/p-aligned PPy NFs/n-silicon Schottky junction diode displayed reasonably high sensitivity ∼23.67 μAmM(-1)cm(-2), good detection limit of ∼1.51 mM with correlation coefficient (R) of ∼0.9966 and short response time (10 s).

Semiconductor diode characterization for total skin electron irradiation

In this paper, a semiconductor diode characterization was performed. The diode characterization was completed using an electron beam with 4 MeV of energy. The semiconductor diode calibration used irradiation with an electron beam in an ion chamber. "In vivo" dosimetry was also conducted. The dosimetry results revealed that the semiconductor diode was a good candidate for use in the total skin electron therapy (TSET) treatment control.

[Comparison between topical anaesthesia with cocaine versus lidocaine plus adrenaline for outpatient laser dacryocystorhinostomy]

OBJECTIVE

To evaluate the effectiveness of topical anaesthesia with cocaine versus lidocaine plus adrenaline for outpatient transcanalicular and endonasal dacryocystorhinostomy (TCLDCR) with diode laser under sedation.

METHODS

A double blind randomised clinical trial was designed using topical anaesthesia for outpatient TCLDCR in the treatment of adult epiphora. A total of 92 patients were enrolled, and randomly allocated to be operated on under sedation and topical anaesthesia with cocaine 4% pledgets versus sedation and topical anaesthesia with lidocaine 2% plus 1/100.000 adrenaline pledgets. Main outcome measures were postoperative comfort, evaluated by a visual analogue scale, presence of secondary effects (blood pressure, heart rate), and resolution of epiphora, evaluated by Munk's scale and endoscopic control.

RESULTS

Patients in both groups reported being comfortable during and immediately after TCLDCR. Visualization of the operative field was adequate, and surgery was successfully completed in all cases. Complications were more common in the cocaine group: Sixteen patients from the cocaine group had high blood pressures, versus 2 patients from the lidocaine group (RR=8). Mean blood loss was 6.09 ml in cocaine group, versus 2.05 ml in lidocaine group (RR=6). Both parameters were statistically significant (p=1,1×10(-9)). There were no cases of postoperative epistaxis requiring nasal packing or hospital admission in any group. Success rate was similar in the 2 groups (86.96% group 1 and 89.13% group 2), after 6 months of follow-up.

CONCLUSIONS

The combination of topical lidocaine and adrenaline is more effective for outpatient transcanalicular and endonasal dacryocystorhinostomy than topical cocaine. Patient comfort was adequate in both groups, but high blood pressure and blood loss more common after cocaine.

Naso-cutaneous fistula following transcanalicular laser dacrocystorhinostomy

We report a case of naso-cutaneous fistula due to thermal injury during transcanalicular laser dacryocystorhinostomy followed by superadded infection with coagulase negative staphylococcus in a diabetic patient. The case highlights the importance of meticulous wound care in the management and possibility of its occurrence even with minor thermal injury in immunocompromised patients.

Use of laser in orthodontics: applications and perspectives

Laser technology got in these years a more and more important role in modern dentistry and, recently, also in orthodontics was proposed the utilization of laser devices. The aim of this work is to describe the utilization of this technology both in soft and hard oral tissues to improve orthodontic treatment. Several cases, with different wavelengths (532, 810, 980, 1064, 2940 and 10600 nm) and in different times of the treatment (before, during and after) are presented. All the cases reported showed, according to the literature, that the use of the laser related to orthodontic treatment offers several advantages when compared with conventional methods. In the soft tissues surgery it allows to reduce or eliminate the use of anesthetic injection, to avoid use of sutures and to bond bracket in dry enamel; associated with orthophosphoric acid, it gives a stronger adhesion of the brackets to the enamel and, in the case of porcelain brackets, it detaches them without damages; at low power (LLLT) it permits to control the pain of the first period after bonding and, by increasing the speed of teeth movement in the bone, reduces the time of the treatment.

Use of laser in orthodontics: applications and perspectives

Laser technology got in these years a more and more important role in modern dentistry and, recently, also in orthodontics was proposed the utilization of laser devices. The aim of this work is to describe the utilization of this technology both in soft and hard oral tissues to improve orthodontic treatment. Several cases, with different wavelengths (532, 810, 980, 1064, 2940 and 10600 nm) and in different times of the treatment (before, during and after) are presented. All the cases reported showed, according to the literature, that the use of the laser related to orthodontic treatment offers several advantages when compared with conventional methods. In the soft tissues surgery it allows to reduce or eliminate the use of anesthetic injection, to avoid use of sutures and to bond bracket in dry enamel; associated with orthophosphoric acid, it gives a stronger adhesion of the brackets to the enamel and, in the case of porcelain brackets, it detaches them without damages; at low power (LLLT) it permits to control the pain of the first period after bonding and, by increasing the speed of teeth movement in the bone, reduces the time of the treatment.

Peripheral dose measurements with diode and thermoluminescence dosimeters for intensity modulated radiotherapy delivered with conventional and un-conventional linear accelerator

The objective of this paper was to measure the peripheral dose (PD) with diode and thermoluminescence dosimeter (TLD) for intensity modulated radiotherapy (IMRT) with linear accelerator (conventional LINAC), and tomotherapy (novel LINAC). Ten patients each were selected from Trilogy dual-energy and from Hi-Art II tomotherapy. Two diodes were kept at 20 and 25 cm from treatment field edge. TLDs (LiF:MgTi) were also kept at same distance. TLDs were also kept at 5, 10, and 15 cm from field edge. The TLDs were read with REXON reader. The readings at the respective distance were recorded for both diode and TLD. The PD was estimated by taking the ratio of measured dose at the particular distance to the prescription dose. PD was then compared with diode and TLD for LINAC and tomotherapy. Mean PD for LINAC with TLD and diode was 2.52 cGy (SD 0.69), 2.07 cGy (SD 0.88) at 20 cm, respectively, while at 25 cm, it was 1.94 cGy (SD 0.58) and 1.5 cGy (SD 0.75), respectively. Mean PD for tomotherapy with TLD and diode was 1.681 cGy SD 0.53) and 1.58 (SD 0.44) at 20 cm, respectively. The PD was 1.24 cGy (SD 0.42) and 1.088 cGy (SD 0.35) at 25 cm, respectively, for tomotherapy. Overall, PD from tomotherapy was found lower than LINAC by the factor of 1.2-1.5. PD measurement is essential to find out the potential of secondary cancer. PD for both (conventional LINAC) and novel LINACs (tomotherapy) were measured and compared with each other. The comparison of the values for PD presented in this work and those published in the literature is difficult because of the different experimental conditions. The diode and TLD readings were reproducible and both the detector readings were comparable.