Effects of Two Remineralizing Agents in Combination with Er:YAG and CO2 Laser Irradiation on Microhardness of Demineralized Enamel: A Preliminary In Vitro Study.

Objectives: This study assessed the effects of two remineralizing agents namely MI Paste Plus containing casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACFP) and Remin Pro containing hydroxyapatite, fluoride and xylitol (HFX) with/without erbium-doped yttrium aluminium garnet (Er:YAG) and CO2 laser irradiation on demineralized enamel microhardness. Materials and Methods: In this in vitro study, 70 sound human premolars were mesiodistally sectioned, demineralized at a pH of 4.6 for 8 hours, and randomly divided into 7 remineralization groups (n=10): of (I) MI Paste Plus (CPP-ACFP), (II) Remin Pro (HFX), (III) MI Paste Plus+CO2 laser (0.7 W power, 50 Hz), (IV) Remin Pro+CO2 laser, (V) MI Paste Plus+Er:YAG laser (1 W power, 10 Hz), (VI) Remin Pro+Er:YAG laser, and (VII) negative control. The Vickers hardness number of specimens was then measured. The groups were compared by one-way ANOVA and Tukey's test (α=0.05). Results: The mean microhardness was 319.8±49.9, 325.3±44.6, 359.4±35.7, 296.4±33.7, 319.9±58.1, 358.9±28.4, and 240.0±41.6 kg/mm2 in groups 1 to 7, respectively. The difference in microhardness was significant among the groups (P<0.0001). Pairwise comparisons revealed significant differences in microhardness between all groups (P≤0.03) except between groups 1 and 2, 1 and 5, 2 and 5, and 3 and 6 (P>0.05). Conclusion: Both Remin Pro (containing HFX) and MI Paste Plus (containing CPP-ACFP) can cause enamel remineralization. MI Paste Plus+CO2 laser irradiation and Remin Pro+Er:YAG laser irradiation were significantly more effective than the application of each remineralizing agent alone.

Prognostic outcome of cervical laser ablation using a holmium yttrium-aluminum-garnet (Ho:YAG) laser for the treatment of cervical intraepithelial neoplasia: A single-center retrospective study.

Objective: Although cervical conization is considered a standard treatment for cervical intraepithelial neoplasia (CIN) 2/3, laser ablation can compensate for the disadvantages of the former. CO2, semiconductor, and holmium yttrium-aluminum-garnet (Ho:YAG) lasers are applied in ablation, but no previous studies have shown the effectiveness of any of these techniques. Here, we retrospectively analyzed the application of the Ho:YAG laser in our hospital to verify its efficacy, and discussed the methods for optimal recurrence detection. Methods: We evaluated the recurrence rates of the pathological condition in patients who underwent laser ablation with a Ho:YAG laser for CIN2/3 at our institution from June 2012 to November 2021. We defined the recurrence as histologically confirmed CIN2 or more advanced stage. Age, preoperative diagnosis, human papillomavirus (HPV) genotype, and postoperative high-risk HPV status were recorded to establish their association with recurrence rates. Results: We performed surgery in 607 patients and the 2-year recurrence rate after interventions was 5.6%. Five patients were diagnosed with invasive cancer at the time of recurrence. Older age significantly correlated with higher risk of recurrence, but preoperative CIN grade and preoperative HPV 16/18 status did not significantly affect it. The postoperative high-risk HPV test was 100% sensitive for detecting recurrence. Conclusions: Laser ablation with the Ho:YAG laser yields promising results. Together with postinterventional management, high-risk HPV test after laser ablation should be conducted after diagnostic conization.This study received the approval from the Ethics Committee of the NHO Tokyo Medical Center (Ethics Committee approval number: R22-067).

Long-term evaluation of the efficacy and safety of Nd:YAG laser vitreolysis for symptomatic vitreous foaters / Avaliação de longo prazo da eficácia e segurança da vitreólise com Nd:YAG laser para moscas volantes sintomáticas

ABSTRACT Purpose: This study aimed to evaluate the long-term safety and efficacy of neodymium-doped yttrium aluminum garnet (Nd:YAG) vitreolysis for symptomatic vitreous floaters as it remains a controversial procedure due to insufficient robust evidence in the literature for the maintenance of the results and absence of adverse effects. Methods: This is an observational extension to the previously presented prospective, randomized, double-blind clinical trial. Eight of thirteen subjects who underwent vitreolysis with YAG laser returned for a late reevaluation, 18 months after the procedure, to evaluate the efficacy and safety of the procedure. Results: All patients maintained the improvement in symptomatology noted after the procedure, with 25% showing complete improvement and a similar proportion (37.5%) reporting significant or partial improvement. Objective improvement in opacity was similar to that found at 6 months follow-up. The NEI-VFQ 25 quality of life questionnaire showed no statistically significant difference in responses between the 6th and 18th month. No adverse effects were noted on clinical examination or reported by patients. Conclusion: Vitreolysis efficacy observed at 6 months of follow-up was maintained until the eighteenth month, with all patients reporting improvement from the pre-procedure state. No late adverse effects were noted. A larger randomized clinical trial is needed to confirm the safety of the procedure.

RESUMO Objetivos: Avaliar a segurança e eficácia a longo prazo da vitreólise com Nd:YAG laser para moscas volantes sintomáticas, uma vez que permanece como um procedimento controverso devido a falta de evidência científica robusta sobre a manutenção dos resultados e ocorrência de efeitos adversos. Métodos: Este estudo é uma extensão observacional de um ensaio clínico prospectivo, randomizado, duplo cego, previamente publicado. Oito de treze pacientes que foram submetidos a vitreólise com YAG laser foram acompanhados para uma reavaliação tardia, dezoito meses após o procedimento, para avaliar a eficácia e segurança do procedimento. Resultados: Todos os pacientes mantiveram a melhora na sintomatologia notada ao final do procedimento original, com 25% dos casos apresentando melhora completa, e uma proporção semelhante (37,5%) demonstrando melhora significativa ou parcial. A melhora objetiva na opacidade foi similar ao achado no seguimento original de 6 meses. O questionário de qualidade de vida NEI-VFQ 25 não demonstrou diferença estatisticamente significativa nas respostas entre o sexto e o décimo oitavo mês de acompanhamento. Nenhum efeito adverso foi notado no exame clínico ou reportado pelos pacientes. Conclusão: A eficácia da vitreólise observada ao sexto mês do acompanhamento foi mantida até o décimo oitavo mês, com todos os pacientes notando algum grau de melhora quando comparado ao estado pré procedimento. Nenhum efeito adverso tardio foi notado. Um ensaio clínico randomizado maior é necessário para confirmar a segurança do procedimento.

Predictors of early catheter replacement after HoLEP. Results from a high-volume laser center

ABSTRACT Introduction: The aim of the study was to investigate clinical and surgical factors associated with early catheter replacement in patients treated with Holmium Laser Enucleation of the Prostate (HoLEP). Materials and Methods: Data of patients treated with HoLEP at our Institution by a single surgeon from March 2017 to January 2021 were collected. Preoperative variables, including non-invasive uroflowmetry and abdominal ultrasonography (US), were recorded. Bladder wall modifications (BWM) at preoperative US were defined as the presence of single or multiple bladder diverticula or bladder wall thickening ≥5 mm. Clinical symptoms were assessed using validated questionnaires. Only events occurred within the first week after catheter removal were considered. Results: Overall, 305 patients were included, of which 46 (15.1%) experienced early catheter replacement. Maintenance of anticoagulants/antiplatelets (AC/AP) therapy at surgery (p=0.001), indwelling urinary catheter (p=0.02) and the presence of BWM (p=0.001) were more frequently reported in patients needing postoperative re-catheterization. Intraoperative complications (p=0.02) and median lasing time (p=0.02) were significantly higher in this group. At univariate analysis, indwelling urinary catheter (p=0.02), BWM (p=0.01), ongoing AC/AP therapy (p=0.01) and intraoperative complications (p=0.01) were significantly associated with early catheter replacement. At multivariate analysis, indwelling urinary catheter (OR: 1.28; p=0.02), BWM (OR: 2.87; p=0.001), and AC/AP therapy (OR: 2.21; p=0.01) were confirmed as independent predictors of catheter replacement. Conclusions: In our experience the presence of indwelling urinary catheter before surgery, BWM and the maintenance of AC/AP therapy were shown to be independent predictors of early catheter replacement after HoLEP.

Histological artifacts associated with laser and electroscalpel gingivectomy: Case series / Artefactos histológicos asociados a gingivectomía con láser y electrobisturí: serie de casos

Introduction. Over time, efforts have been invested in the design of new instruments that overcome the disadvantages of the gold standard instrument in surgery, the scalpel. As a result, electronic equipment has emerged such as the electric scalpel and laser devices. The available evidence on these instruments suggests that the tissue response is related to each instrument's physical and biological cutting principles. Objective. To compare the histological changes in gingiva samples associated with surgical cutting performed with a 940 nm diode laser, a 2780 nm erbium, chromium: yttriumscandium-gallium-garnet (Er,Cr:YSGG) laser, and an electric scalpel, by presenting a series of cases. Case presentation. We present three cases of healthy patients undergoing cosmetic surgery. The clinical examination revealed exposure of a keratinized gingiva band greater than 4 mm, normal color and texture in gingival tissue, with a firm consistency and no bleeding on periodontal probing. Gingivectomy was indicated with the following protocols: Diode laser of 940 nm at 1 W, in continuous mode; Er,Cr:YSGG laser of 2780 nm at 2.5 W, 75 Hz, H mode, air 20, water 40, gold tip MT4); and electric scalpel in cutting mode at power level four. Gingival tissue samples were taken and stored in 10% formaldehyde for histological analysis. Conclusion. All the evaluated cutting instruments generated histological changes produced by the thermal effect, the main ones being collagen coagulation and carbonization. The depth of thermal damage caused by the 2780 nm Er,Cr:YSGG laser was much lesser than that induced by the electric scalpel and the 940 nm diode laser.

Introducción. Históricamente se ha invertido esfuerzo en el diseño de nuevos instrumentos que superen las desventajas del estándar de referencia en cirugía, el bisturí. Como consecuencia de esto, han surgido equipos electrónicos como el electrobisturí y los diferentes dispositivos de tecnología láser. La información disponible sobre estos instrumentos sugiere que la respuesta del tejido intervenido está influenciada por los principios físicos y biológicos de corte del instrumento. Objetivo. Comparar los cambios histológicos en muestras de encía asociados al corte quirúrgico realizado con láser de diodo de 940 nm, láser de erbio, cromo: itrio-escandio-galio-granate (Er,Cr:YSGG) (2780nm) y electrobisturí mediante una presentación de serie de casos. Presentación de los casos. Se presentan tres casos de pacientes sanos sometidos a cirugía estética. El examen clínico reveló la exposición de una banda gingival queratinizada mayor de 4 mm, tejido gingival de color y textura normales, de consistencia firme y sin sangrado al sondaje periodontal. Se indicó gingivectomía con los siguientes protocolos: láser de diodo de 940 nm a 1 W, en modo continuo; láser de Er,Cr:YSGG de 2780 nm a 2,5 W, 75 Hz, modo H, aire 20, agua 40, punta de oro MT4; y bisturí eléctrico en modo de corte, a nivel de potencia cuatro. Se tomaron muestras de tejido gingival y se almacenaron en formaldehído al 10 % para su análisis histológico. Conclusión. Los tres instrumentos de corte generaron cambios histológicos producidos por el efecto térmico; los principales fueron coagulación del colágeno y carbonización. La profundización del daño térmico causada por el láser de Er,Cr:YSGG de 2780 nm fue mucho menor que la generada por el electrobisturí y por el láser de diodo de 940 nm.

Preliminary results of a new surgical technique: bladder mucosal graft harvested with holmium:YAG (HO:YAG) laser. A new option in bulbar replacement urethroplasty?

OBJECTIVE: To describe the technique of transurethral harvesting of bladder mucosal graft using the Holmium:YAG (Ho-YAG) laser and describe the preliminary results from 7 cases where this graft was used for urethroplasty. MATERIALS AND METHODS: We performed a single-stage dorsal onlay urethroplasty using bladder mucosal graft in 7 patients with anterior urethral stricture. Transurethral harvesting was performed with the Ho-YAG laser. We performed a prospective and descriptive analysis with uroflowmetry performed at 30, 90 and 180 days after surgery and applied the PROM translated into Portuguese before and 6 months after urethroplasty. RESULTS: Seven patients were included, 2 (28.5%) with penile urethral stricture, and 5 (71.5%) with bulbar urethral stricture. Mean stricture length was 50mm (range 35-60mm). Stricture etiology was trauma in 3 (42.9%) patients, iatrogenic in 1 (14.3%) patient, and idiopathic in 3 (42.9%) patients. Two patients (28.6%) had previously undergone ventral buccal mucosa urethroplasty. Mean bladder mucosal graft length was 52.86mm (± 13.801), and mean harvest time was 46.43min (± 14.639). Dorsal onlay urethroplasty using bladder mucosa was successfully completed in 5 patients (71.4%). Two patients (28.6%) couldn't have the procedure completed using bladder mucosa, one due to thermal damage of the graft during harvesting, and one due to insufficient graft length. In both cases the procedure was completed using buccal mucosa. Two patients (28.6%) experienced minor hematuria between the twelfth and eighteenth postoperative day, but neither required hospitalization and/or additional procedures. All patients achieved normalization of peak flow, and this was maintained throughout the follow-up period. Mean peak flow was 17.8 ml/s (± 3.271) at 30 days, 20.6 ml/s (± 5.413) at 90 days, and 19.6 ml/s (± 8.019) 180 days. Mean IPSS score decreased from 19.3 to 5.4. Similar improvements were also seen in the ICIQ-MLUTS Score (a mean drop from 3.8 to 2.0) and Peeling's Voiding Picture Score (a mean drop from 4.0 to 2.2). Quality of Life improved post urethroplasty, with increases in EQ-5D (from 0.6371 to 0.7285) and EQ-VAS (from 58.0 to 84.0). CONCLUSION: Transurethral harvesting of bladder mucosa using the Holmium laser (Ho-YAG) is feasible and reproducible. Our preliminary experience suggests that bladder mucosa grafts achieve comparable results to other grafts when used for dorsal onlay urethroplasty. Further research is needed to confirm these results.

Pulse-modulated Holmium:YAG Laser vs the Thulium Fiber Laser for Renal and Ureteral Stones: A Single-center Prospective Randomized Clinical Trial.

PURPOSE: We sought to compare the clinical effectiveness of the pulse-modulated Ho:YAG (holmium:yttrium-aluminum-garnet) laser and the thulium laser fiber for ureteroscopic stone management in a randomized clinical trial. The primary outcome was the ureteroscope time required to adequately fragment stones to 1 mm or less. Secondary outcomes were stone-free rate, complications, subjective surgeon measurement of laser performance, patient related stone quality of life outcomes, and measurements of laser efficiency. MATERIALS AND METHODS: An Institutional Review Board-approved randomized clinical trial was conducted to randomize patients to outpatient treatment with either the Moses 2.0 or thulium laser fiber in a 1:1 manner after stratification into groups based on the maximal diameter of treated stone (3-9.9 mm or 10-20 mm). Patient, stone, and operative parameters were compared using the appropriate categorical/continuous and parametric/nonparametric statistical tests (SPSS 25). RESULTS: From July 16, 2021 to March 11, 2022, 108 patients were randomized and had primary endpoint data available for analysis; 52 patients were randomized to Ho:YAG and 56 patients to thulium laser fiber. Groups were well balanced with no significant differences observed for patient or stone characteristics. Ureteroscope time was not significantly different between modalities (Ho:YAG mean 21.4 minutes vs thulium laser fiber mean 19.9 minutes, P = .60), or within subgroup analysis by stone size, median Hounsfield units, or stone location. There were no significant differences observed in the stone-free rate and complications rate between the 2 lasers. CONCLUSIONS: This randomized clinical trial suggests no significant clinical advantage of one laser technology over the other. Surgeon and institutional preference are the best approach when selecting one or the other.

Impacto da irradiação com laser ND: YAG sobre primer de adesivo convencional na adesão à dentina / Impact of Nd: YAG laser irradiation on primer of conventional adhesive in adhesion to dentin

A irradiação da dentina com o laser Nd:YAG mostra-se promissora para a qualidade da adesão, desde que aplicada sob parâmetros específicos e em etapas definidas. O objetivo deste estudo é avaliar de forma comparativa, o impacto da irradiação com laser de Nd:YAG sobre a formação e estabilidade da camada híbrida em dentina humana, pré-tratada com ácido e primer de sistema adesivo convencional, "in vitro". Setenta molares hígidos tiveram suas raízes e porções coronárias seccionadas horizontalmente, até completa exposição de dentina oclusal. As amostras foram divididas em: G1 (controle n=20); G2 (experimental n=20), sendo 10 dentes de cada grupo destinados ao microcisalhamento (MC) e 10 dentes à microscopia eletrônica de varredura (MEV). Nos 30 dentes restantes analisou-se: textura por Tomografia Computadorizada de Feixe Cônico (AT=15); e Espectroscopia de Infravermelho por Transformada de Fourier (FTIR=15) em 3 momentos: dentina controle; após tratamento com ácido + primer; e posterior à irradiação a laser. Estatisticamente, optou-se por ANOVA 1 fator, Qui Quadrado de Pearson, teste T e múltiplas comparações de Tukey com significância de 5%. A FTIR evidenciou redução dos níveis de fosfato e carbonato nos momentos primer e após irradiação laser, porém não havendo desnaturação do colágeno exposto. A análise de textura evidenciou uma tendência à formação de um tecido mais padronizado após o uso do laser. O teste de MC evidenciou valores médios de 36,5 e 35,2MPa para G1 e G2 respectivamente (p>0,05) e portanto, de forma imediata, o laser não mostrou efeitos deletérios ao processo adesivo. Além disso, observou-se maior penetrabilidade do adesivo na avaliação em MEV após a aplicação do laser. Novas pesquisas com avaliação longitudinal mostram-se necessárias para verificar se o efeito do laser pode ter sido protetor da degradação hidrolítica, visto que há uma redução do conteúdo de água local durante a formação da camada híbrida (AU).

Irradiation of dentin with the Nd:YAG laser shows promise for the quality of adhesion, as long as it is applied under specific parameters and in defined steps. The objective of this study is to comparatively evaluate the impact of irradiation with Nd:YAG laser on the formation and stability of the hybrid layer in human dentin, pretreated with acid and primer of conventional adhesive system, "in vitro". Seventy healthy molars had their roots and coronal portions horizontally sectioned, until complete exposure of occlusal dentin. The samples were divided into: G1 (control n=20); G2 (experimental n=20), with 10 teeth from each group destined for microshearing (MC) and 10 teeth for scanning electron microscopy (SEM). In the 30 remaining teeth analyzed: texture by Cone Beam Computed Tomography (AT=15); and Fourier Transform Infrared Spectroscopy (FTIR=15) in 3 moments: dentin control; after treatment with acid + primer; and after laser irradiation. Statistically, we opted for 1-way ANOVA, Pearson's Chi Square, T test and Tukey's multiple comparisons with a significance of 5%. FTIR showed a reduction in phosphate and carbonate levels in the primer moments and after laser irradiation, but there was no denaturation of the exposed collagen. The texture analysis evidenced a trend towards the formation of a more expressive tissue after the use of the laser. The CM test showed mean values of 36.5 and 35.2MPa for G1 and G2 respectively (p>0.05) and therefore, immediately, the laser showed no deleterious effects on the adhesive process. In addition, greater penetrability of the adhesive was observed in the SEM evaluation after laser application. New studies with longitudinal evaluation are necessary to verify if the laser effect could have been protected from hydrolytic degradation, since there is a reduction in the local water content during the formation of the hybrid layer (AU).

Efficacy of laparoscopic choledochoscopy combined with holmium laser lithotripsy versus traditional laparotomy in treatment of bile duct stones： A Meta－analysis / 临床肝胆病杂志

ObjectiveTo systematically review the efficacy and safety of laparoscopic choledochoscopy combined with holmium laser lithotripsy through a meta－analysis. MethodsThis study was conducted based on PRISMA guidelines， with a PROSPERO registration number of CRD42023406221. Chinese databases including CNKI， Wanfang Data， and VIP and foreign language databases such as PubMed， Embase， the Cochrane Library， and Web of Science were searched for original articles on traditional laparotomy versus laparoscopic choledochoscopy combined with holmium laser lithotripsy in the treatment of bile duct stones. Dichotomous variables were assessed by odds ratio （OR） and 95% confidence interval （CI）， while continuous variables were assessed by weighted mean difference （WMD） and 95%CI， and a sensitivity analysis was performed for outcome measures with relatively high heterogeneity. The Begg test and Egger test were used to evaluate publication bias. Stata 15.0 and Review Manager 5.3 were used to perform the statistical analysis. ResultsA total of 26 retrospective studies from China were included in this study， with 2 238 patients in total. The meta－analysis showed that compared with traditional laparotomy for the treatment of bile duct stones， laparoscopic choledochoscopy combined with holmium laser lithotripsy had significantly shorter time of operation （WMD＝－1.26， 95%CI： －1.36 to －1.16， P<0.001）， length of hospital stay （WMD＝－1.93， 95%CI： －2.64 to －1.12， P <0.001）， and time to bowel function recovery （WMD＝－1.52， 95%CI： －1.68 to －1.35， P<0.001）， significantly less intraoperative blood loss （WMD＝－1.79， 95%CI： －1.93 to －1.66， P<0.001）， a significantly lower rate of intraoperative residual stone （OR＝0.15， 95%CI： 0.11－0.20， P<0.001）， and significantly fewer complications （OR＝0.17， 95%CI： 0.13－0.23， P<0.001）. ConclusionCompared with traditional laparotomy， laparoscopic choledochoscopy combined with holmium laser lithotripsy shows better efficacy in the treatment of bile duct stones.

Response of dental pulp capped with calcium-silicate based material, calcium hydroxide and adhesive resin in rabbit teeth

Direct pulp capping induces a local inflammatory process. Several biomaterials have been used for this procedure. The aim of this study was to compare the dentinal bridge thickness using three different pulp capping biomaterials with the conventional technique (high speed diamond bur) or Er-Yag laser, 1 month after pulp effraction. Materials and Methods: Forty two Class V cavities were prepared on the buccal surface of 4 maxillary incisors and 2 mandibular incisors of New Zealand rabbits. Specimens were divided into 6 treatment groups. Teeth were treated with: In Group 1: Er-Yag laser and Biodentine® (Septodont), in Group 2: Er: Yag laser and calcium hydroxide (Dycal® Dentsply), in Group 3: Er: Yag laser and adhesive system (Prime& Bond® NT Dentsply), in Group 4: high speed diamond bur and Biodentine® (Septodont), in Group 5: high speed diamond bur and calcium hydroxide (Dycal® Dentsply), and in Group 6: high speed diamond bur and adhesive system (Prime& Bond® NT Dentsply). The preparation was done with copious irrigation. The animals were sacrificed at 30 days and the teeth were extracted and prepared for histological analysis. Results: In the group of « laser Er-Yag ¼, iatrogenic pulpal wounds treated with Biodentine® were covered with a thick hard tissue barrier after 1 month. The difference was not significant with the groups of Dycal® used with Er: Yag laser and high speed diamond bur. Prime& Bond® NT Dentsply specimens showed a thin dentinal bridge layer. Conclusion: At 1 month, Er-Yag laser proved to be useful with Biodentine® for direct pulp capping procedures

Transurethral flexible ureteroscopic incision and drainage with holmium laser in the treatment of parapelvic renal cysts: A retrospective study

ABSTRACT Background: We aimed to investigate the clinical efficacy and safety of transurethral flexible ureteroscopic incision and drainage with holmium laser in the treatment of parapelvic renal cysts. Materials and Methods: Between October 2017 and April 2021, the clinical data of 65 patients with parapelvic renal cysts were evaluated retrospectively. Thirty-one patients with parapelvic cysts (Group 1) underwent a transurethral flexible ureteroscopic incision and drainage with a holmium laser, whereas the other 34 patients (Group 2) underwent retroperitoneal laparoscopic unroofing. The patients' clinical features were documented. The surgery time, intraoperative blood loss, hospitalization time, complications and cyst size were recorded and statistically assessed one year following the procedure. Results: All of the patients were successfully treated with flexible ureteroscopic incision and drainage or retroperitoneal laparoscopic unroofing. In terms of clinical parameters, such as age, gender, BMI, location, cyst size, and Bosniak classification of renal cysts, no statistically significant difference was detected between Groups 1 and 2. Compared to the control group (Group 2), Group 1 demonstrated a shorter surgery duration, less intraoperative blood loss, and a shorter hospital stay (p < 0.001). However, no significant differences in complications and cyst size were observed between the two groups one year after the surgery (p > 0.05). Conclusions: Transurethral flexible ureteroscopic incision and drainage with holmium laser in the treatment of parapelvic renal cysts has obvious advantages over traditional surgery, and is worthy of advancement and application, but its long-term effect needs further follow-up studies.

Transurethral flexible ureteroscopic incision and drainage with holmium laser in the treatment of parapelvic renal cysts: A retrospective study.

BACKGROUND: We aimed to investigate the clinical efficacy and safety of transurethral flexible ureteroscopic incision and drainage with holmium laser in the treatment of parapelvic renal cysts. MATERIALS AND METHODS: Between October 2017 and April 2021, the clinical data of 65 patients with parapelvic renal cysts were evaluated retrospectively. Thirty-one patients with parapelvic cysts (Group 1) underwent a transurethral flexible ureteroscopic incision and drainage with a holmium laser, whereas the other 34 patients (Group 2) underwent retroperitoneal laparoscopic unroofing. The patients' clinical features were documented. The surgery time, intraoperative blood loss, hospitalization time, complications and cyst size were recorded and statistically assessed one year following the procedure. RESULTS: All of the patients were successfully treated with flexible ureteroscopic incision and drainage or retroperitoneal laparoscopic unroofing. In terms of clinical parameters, such as age, gender, BMI, location, cyst size, and Bosniak classification of renal cysts, no statistically significant difference was detected between Groups 1 and 2. Compared to the control group (Group 2), Group 1 demonstrated a shorter surgery duration, less intraoperative blood loss, and a shorter hospital stay (p < 0.001). However, no significant differences in complications and cyst size were observed between the two groups one year after the surgery (p > 0.05). CONCLUSIONS: Transurethral flexible ureteroscopic incision and drainage with holmium laser in the treatment of parapelvic renal cysts has obvious advantages over traditional surgery, and is worthy of advancement and application, but its long-term effect needs further follow-up studies.

Understanding cavitation-related mechanism of therapeutic ultrasound in the field of urology: Part I of therapeutic ultrasound in urology.

Shock waves are commonly used in the field of urology. They have two phases, positive and negative, and the bubble generation is roughly classified into acoustic cavitation (AC) and laser-induced cavitation (LIC). We evaluated the occurrence of cavitation, its duration, the area of interest, and the maximal diameter of the cavitation bubbles. Changes in AC occurred at 0.2 ms with the highest number of bubbles and disappeared at 0.6 ms. The bubble size was 2 mm in diameter. Changes in LIC bubbles were observed in three pulse modes. The short pulse showed an initial bubble starting at 0.005 ms, which reached its largest size at 0.4 to 0.6 ms. The long pulse showed an initial bubble starting at 0.005 ms, which reached its largest size at 0.4 ms with the formation of an additional lagena-shaped bubble at 0.6 ms. The distance mode of MOSES showed two signal peaks with the formation of two consecutive bubbles at 0.2 and 0.6 ms. The main difference in the laser beams between the long-pulse and the MOSES modes was the continuity and the peak power of the laser beam. The diameters parallel to the laser direction were 6.8, 8.6, and 9.7 mm at 1, 2, and 3 J, respectively, in the short pulse. While the cavitation bubbles rupture, ejectile force occurs in numerous directions, transmitting high enough energy to break the targets. Cavitation bubbles should be regarded as energy and the mediators of energy for stone fragmentation and tissue destruction.

Comparing Pediatric Ureteroscopy Outcomes with SuperPulsed Thulium Fiber Laser and Low-Power Holmium:YAG Laser.

PURPOSE: The thulium fiber laser is a promising new lithoptripsy technology never before studied in the pediatric population. Our center adopted the first platform in North America, the SuperPulsed thulium fiber laser (SPTF). We aimed to compare outcomes in pediatric ureteroscopy using the SPTF to those using the gold standard, low-power holmium:yttrium-aluminum-garnet (Ho:YAG) laser. MATERIALS AND METHODS: This is a retrospective, consecutive cohort study of unilateral ureteroscopy with laser lithotripsy performed in pediatric patients from 2016 to 2021 as an early adopter of the SPTF. Thirty-day complications and stone-free status, defined as the absence of a stone fragment on followup imaging within 90 days, were analyzed using logistic regression. Operative times were compared using linear regression. Propensity scores for use of SPTF were used in regression analyses to account for potential cohort imbalance. RESULTS: A total of 125 cases were performed in 109 pediatric patients: 93 with Ho:YAG and 32 with SPTF. No significant difference was noted in age (p=0.2), gender (p=0.6), stone burden (p >0.9) or stone location (p=0.1). The overall stone-free rate was 62%; 70% with SPTF and 59% with Ho:YAG. The odds of having a residual stone fragment were significantly lower with SPTF than with Ho:YAG (OR=0.39, 95% CI: 0.19-0.77, p=0.01). There was no significant difference in operative time (p=0.8). Seven (25%) complications were noted with SPTF and 19 (22%) with Ho:YAG (p=0.6). CONCLUSIONS: The SPTF laser was associated with a higher stone-free rate than the low-power Ho:YAG laser without compromising operative time and safety.

Efficacy of mitomycin C in modified transcanalicular diode laser dacryocystorhinostomy / Eficácia da mitomicina C na dacriocistorrinostomia transcanalicular com laser diodo modificada

ABSTRACT Objective: To evaluate the efficacy of mitomycin C in anatomical and functional success after modified transcanalicular diode laser dacryocystorhinostomy. Methods: A prospective, double-blinded, randomized placebo-controlled study compared the effect of topical mitomycin C on modified transcanalicular diode laser dacryocystorhinostomy. Group 1 had modified transcanalicular diode laser dacryocystorhinostomy with topical saline, while Group 2 had modified transcanalicular diode laser dacryocystorhinostomy with topical mitomycin C. Success was defined as anatomical patency and relief of symptoms at the end of 6 months. Results: Six months after surgery, Group 1 (30 patients) showed anatomical and functional success rates of 86.7% and 83.3%, respectively. Group 2 (32 patients) showed anatomical and functional success rates of 87.5% and 84.3%, respectively. There was no statistically significant difference between the groups 1 and 2 (p = 1.000). Conclusion: The use of mitomycin C did not improve the anatomical and functional success rates of modified transcanalicular diode laser dacryocystorhinostomy compared to placebo.

RESUMO Objetivo: Avaliar a eficácia da mitomicina C no sucesso anatômico e funcional após dacriocistorrinostomia transcanalicular com laser de diodo. Métodos: Estudo prospectivo, duplo-cego, randomizado e controlado por placebo. Comparou o efeito da mitomicina C tópica na dacriocistorrinostomia transcanalicular com laser de diodo. No Grupo 1, foi utilizada apenas solução salina tópica, enquanto no Grupo 2 foi utilizada mitomicina C tópica. O sucesso foi definido como permeabilidade da via lacrimal e alívio dos sintomas ao final de 6 meses. Resultados: Seis meses após a cirurgia, o Grupo 1 (30 pacientes) apresentou taxas de sucesso anatômico e funcional de 86,7% e 83,3%, respectivamente. O Grupo 2 (32 pacientes) apresentou taxas de sucesso anatômico e funcional de 87,5% e 84,3%, respectivamente. Não houve diferença estatística significante entre os Grupos 1 e 2 (p=1,000). Conclusão: O uso de mitomicina C não melhora as taxas de sucesso anatômico e funcional do dacriocistorrinostomia transcanalicular com laser de diodo em comparação ao placebo.

The effect of Er: yttrium aluminum garnet laser irrigation on the root canal smear layer and root canal microhardness / 中华老年医学杂志

Objective:To examine the effects of different endodontic irrigation methods on root canal morphology.Methods:We collected 20 extracted single-root premolars from elderly patients(≥60 years)with periodontitis and randomly divided them into 5 groups.Group A: syringe irrigation; Group B: P5 ultrasonic irrigation, Group C: 0.20 W Er: yttrium aluminum garnet(YAG)laser irrigation; Group D: 0.30 W Er: YAG laser irrigation; and Group E; 0.35 W Er: YAG laser irrigation.Changes in the smear layer in the root canal and the hardness of the root canal were assessed.Results:After treatment with different root canal cleaning methods, the scores of smear layer removal for Groups A, B, C, D and E were(4.67±0.27), (3.08±0.57), (2.83±0.43), (1.17±0.19)and(2.87±0.50), respectively.There were statistically significant differences between them( F=35.946, P<0.01). Among them, Group B, C, D and E had better smear layer removal than Group A, and the differences were statistically significant(all P<0.01). Group D had better removal of the smear layer than Groups B, C and E, and the differences were statistically significant( P<0.01); Values for dentin microhardness of Groups A, B, C, D and E were(58.98±5.54), (55.19±5.71), (56.04±3.96), (66.65±3.23)and(45.68±7.58), respectively, with statistically significant differences( F=5.83, P<0.05), and for laser-based irrigation, the value for dentin microhardness of Group D was higher than those of groups C and B(all P<0.05). Conclusions:Laser-based root canal irrigation is better than traditional irrigation methods, with 0.30 W Er: YAG laser achieving maximal removal of the smear layer and at the same time having the least impact on root canal hardness.

Effect of 1 064-nm Q-switched Nd:YAG laser on cell viability, protease activity and structures of Malassezia furfur / 中华皮肤科杂志

Objective:To investigate the effect of 1 064-nm Q-switched Nd:YAG laser at different energy settings on cell viability, protease activity and structures of Malassezia furfur. Methods:Cultured standard strains of Malassezia furfur were divided into several groups to be irradiated with 1 064-nm Q-switched Nd:YAG laser at different energies of 0 (control group) , 500, 600, 700, 800 and 900 mJ, respectively. Then, fungal suspensions in the above groups were inoculated onto the Leeming & Notman medium separately. After 7-day culture, the diameter and number of colonies were measured to evaluate the fungal cell viability, the protease activity was measured by using the whole-milk plate medium, and the ultrastructure of Malassezia furfur in each group was observed by transmission electron microscopy. One-way analysis of variance was used for comparisons among multiple groups, least significant difference- t test for multiple comparisons, and Pearson correlation analysis for analyzing correlations of laser energy with colony diameter, number and protease activity. Results:The colony diameter and number both significantly differed among the control group, 500-, 600-, 700-, 800- and 900-mJ groups (colony diameter: 4.05 ± 0.69, 3.76 ± 0.51, 3.28 ± 0.41, 3.09 ± 0.72, 2.54 ± 0.64 and 2.43 ± 0.41 mm, respectively; colony number: 4 787 ± 597, 4 287 ± 761, 1 879 ± 275, 1 082 ± 248 and 209 ± 42, 72 ± 31 colony-forming units, respectively; F = 14.83, 231.85, respectively, both P < 0.05) , and were significantly decreased in the 600-, 700-, 800- and 900-mJ groups compared with the control group (all P < 0.05) . The laser energy was negatively correlated with the colony diameter and number ( r = -0.67, -0.91, respectively, both P < 0.05) . The protease activity significantly differed among the control group, 500-, 700- and 900-mJ groups ( F = 346.60, P < 0.05) , and was significantly lower in the 700- and 900-mJ groups than in the control group (both P < 0.05) . There was a negative correlation between the laser energy and protease activity ( r = -0.94, P < 0.05) . Transmission electron microscopy showed intact fungal structures in the control group, relatively intact fungal structures in the 500-mJ group, and obviously damaged fungal structures in the 600- to 900-mJ groups, and the greater the laser energy, the more severely the fungal structures were damaged. Conclusion:The 1 064-nm Q-switched Nd:YAG laser could affect the cell viability of and protease activity in Malassezia furfur, and damage its structures.

Comparison of mean operative time in patients undergoing Ho: YAG laser lithotripsy and pneumatic lithotripsy in ureterorenoscopy for ureteric calculus.

OBJECTIVE: To compare the mean operative time (MOT) in patients undergoing Ho: YAG laser lithotripsy (LL) and pneumatic lithotripsy (PL) for ureteric stones. METHODS: This randomized study was conducted at Armed Forces Institute of Urology (AFIU) Rawalpindi, Pakistan from July 2016 to November 2018. Non probability consecutive sampling technique utilized to enroll 60 patients of both gender aged 18-60 years, having ureteric calculus ≤1.5cm. Randomization was done into group I (LL) and II (PL) via computer generated number tables. Six Consultant Urologists performed surgeries under spinal anesthesia utilizing Swiss Lithoclast® Master (EMS+ S.A. Switzerland) in group II and holmium laser fiber (365µm, 8-10Hz, 9.6-16W, 2100nm wavelength) in group I respectively. MOT was noted from insertion of cystoscope till removal out of meatus. Data obtained was analyzed through IBM SPSS 24.0. RESULTS: Analysis involved 60 patients (30 each group) having similar baseline characteristics (age, gender, laterality, location). There was statistically significant different MOT between LL & PL (25.48±6.99 vs 34.83± 7.47 minutes, p < 0.001). Data stratification with respect to age, gender, laterality and stone location revealed similar trend. Lithotripsy technique significantly affected MOT (p < 0.001) on Multiple Linear Regression Analysis. CONCLUSIONS: Ho: YAG LL is an efficient technique when compared with PL in terms of MOT for ureteric stones.

Effect of Different Surface Treatments and Pressure Conditions on Shear Bond Strength of Zirconia Ceramic to Composite Resin.

Objectives: The aim of this study was to assess the shear bond strength (SBS) of zirconia ceramic to composite resin with various surface treatments following pressure changes. Materials and Methods: Totally, 135 zirconia blocks were prepared by computer-aided design/computer-aided manufacturing technology. The samples were divided into 9 groups (n=15). Three surface treatments including sandblasting, tribo-chemical preparation, and laser application were used. For each method, 45 samples were considered and tested under different pressure conditions. Z-Prime Plus primer was used for bonding of all samples to composite cylinders. All specimens were stored in water for 24 h, underwent thermocycling, and were then placed in a pressure chamber under normal-, high-, and low-pressure conditions. Then, the SBS test was performed for each sample. Data were analyzed by two-way and one-way ANOVA (α=0.05). Results: The SBS was significantly higher in sandblasting and tribochemical preparation compared with laser irradiation (P<0.05). There was no statistically significant difference in SBS of sandblasting and tribochemical preparation methods (P>0.05). Sandblasting, tribochemical preparation, and laser methods did not show a significant difference in SBS at different pressures (P>0.05). Conclusion: Sandblasting and tribochemical preparation yielded a higher SBS than laser. Different pressures had no effect on SBS, irrespective of surface preparation method.

Adaptación de cofias Co-Cr fabricadas por colado por inducción y fusión selectiva láser en CAD/CAM / Adaptation of Co-Cr copings made by induction casting and selective laser melting in CAD/CAM

RESUMEN Existen pocos estudios que comparen la adaptación de cofias de Cobalto-Cromo (Co-Cr) fabricadas por la técnica de cera perdida colada por centrifugación por inducción (CPCI) y fusión selectiva láser (SLM) en diseño y fabricación asistida por computador (CAD/CAM). Objetivo: Evaluar in vitro la adaptación marginal e interna de cofias unitarias de aleación Co-Cr sobre una línea de terminación tipo chamfer, fabricadas con la técnica CPCI y SLM en CAD/CAM. Material y Métodos: Se fabricaron 13 cofias de aleación Co-Cr para cada técnica. Se evaluó la adaptación marginal e interna utilizando la técnica de réplica de silicona. Cada réplica fue seccionada en sentido vestíbulo-palatino y mesio-distal para luego ser analizadas a nivel cervical, axial y oclusal mediante un estéreomicroscopio con aumento de 40X. Resultados: La discrepancia marginal de las cofias Co- Cr fabricadas por la técnica SLM fue 38.1μm y para la técnica CPCI fue 42,22μm sin diferencias significativas (p>0,05). La discrepancia axial para las cofias fabricadas por técnica CPCI fue de 42,02μm y para la técnica SLM de 60,16μm con diferencia significativa (p<0.05). La discrepancia oclusal para las cofias confeccionadas por la técnica CPCI fue de 101,94 μm y para la técnica SLM fue de 232,13μm con diferencia significativa (p<0,05). Conclusiones: La adaptación marginal fue similar para las técnicas CPCI y SLM pero sin diferencias estadísticamente significativas. La adaptación interna fue mejor para la técnica CPCI que para la técnica SLM con diferencias estadísticamente significativas.

SUMMARY There are few studies comparing the fit of cobalt-chromium copings (Co-Cr) manufactured by induction centrifugal casting technique and selective laser melting (SLM) in CAD/CAM. Objective: The purpose of this study was to evaluate in vitro the marginal and internal fit of Co-Cr alloy unit copings on a chamfer termination line manufactured by induction centrifugal casting technique (CPCI) and selective laser melting (SLM) in CAD/CAM. Material and methods: Thirteen Co-Cr unit copings were made for each technique. Marginal and internal fit were evaluated with the replica technique. Each sample was cross sectioned in the vestibular-palatine and mesio-distal direction, then observed in a stereomicroscope at a 40X magnification and measured at the cervical, axial and occlusal areas. Results: The marginal discrepancy of Co-Cr copings manufactured by the SLM technique was 38.1 μm and for the CPCI technique it was 42.22 μm without significant differences (p > 0.05). The axial discrepancy for the copings manufactured by CPCI technique was 42.02 μm and for the SLM technique of 60.16 μm with significant difference (P < 0.05). The occlusal discrepancy for the copings made by the CPCI technique was 101.94 μm and for the SLM technique was 232.13 μm with significant difference (P < 0.05). Conclusions: The marginal adaptation was similar for CPCI and SLM techniques but without statistically significant differences. The internal adaptation was better for the CPCI technique than for the SLM technique with statistically significant differences.