Chemical (Alkali) Burn-Induced Neurotrophic Keratitis Model in New Zealand Rabbit Investigated Using Medical Clinical Readouts and In Vivo Confocal Microscopy (IVCM).

PURPOSE: Chemical eye injury is an acute emergency that can result in vision loss. Neurotrophic keratitis (NK) is the most common long-term manifestation of chemical injury. NK due to alkali burn affects ocular surface health and is one of its most common causes. Here, we established a rabbit model of corneal alkali burns to evaluate the severity of NK-associated changes. MATERIAL METHODS: Alkali burns were induced in NZ rabbits by treating the cornea with (i) a 5 mm circular filter paper soaked in 0.75 N NaOH for 10 s (Mild NK) and (ii) trephination using a guarded trephine (5 mm diameter and 150-micron depth), followed by alkali burn, with a 5 mm circular filter paper soaked in 0.75 N NaOH for 10 s (a severe form of NK). Immediately after, the cornea was rinsed with 10 mL of normal saline to remove traces of NaOH. Clinical features were evaluated on Day 0, Day 1, Day 7, Day 15, and Day 21 post-alkali burn using a slit lamp, Pentacam, and anterior segment optical coherence tomography (AS-OCT). NK-like changes in epithelium, sub-basal nerve plexus, and stroma were observed using in vivo confocal microscopy (IVCM), and corneal sensation were measured using an aesthesiometer post alkali injury. After 21 days, pro-inflammatory cytokines were evaluated for inflammation through ELISA. RESULTS: Trephination followed by alkali burn resulted in the loss of epithelial layers (manifested using fluorescein stain), extensive edema, and increased corneal thickness (550 µm compared to 380 µm thickness of control) evaluated through AS-OCT and increased opacity score in alkali-treated rabbit (80 compared to 16 controls). IVCM images showed complete loss of nerve fibers, which failed to regenerate over 30 days, and loss of corneal sensation-conditions associated with NK. Cytokines evaluation of IL6, VEGF, and MMP9 indicated an increased angiogenic and pro-inflammatory milieu compared to the milder form of NK and the control. DISCUSSION: Using clinical parameters, we demonstrated that the alkali-treated rabbit model depicts features of NK. Using IVCM in the NaOH burn animal model, we demonstrated a complete loss of nerve fibers with poor self-healing capability associated with sub-basal nerve degeneration and compromised corneal sensation. This pre-clinical rabbit model has implications for future pre-clinical research in neurotrophic keratitis.

Comparison of Chemical Matricectomy with Trichloroacetic Acid, Phenol, or Sodium Hydroxide for Ingrown Toenails: A Systematic Review and Network Meta-Analysis.

is missing (Short communication).

[Effect of dental implants with conditioned surface based on sodium hydroxide in patients with osteoporosis]. / Otsenka éffektivnosti primeneniia dental'nykh implantatov s konditsionirovannoi poverkhnost'iu na osnove gidroksida natriia u patsientov s osteoporozom.

The problem of improving the efficiency of implantological treatment of patients with osteoporosis (OP) today remains relevant due to the high frequency of postoperative complications. Among the main factors affecting the success of dental implant treatment, the nature of the implant surface is essential. Patients with adentia and OP especially relevant in use of dental implants with optimized surface, air conditioned component influencing bone remodelling. OBJECTIVE: Evaluation of the effectiveness of dental implants with a conditioned surface based on sodium hydroxide in men with osteoporosis. MATERIAL AND METHODS: The study included 60 men 54-65 years of age in need of dental implants of which 40 were diagnosed with OP. Patients with OP were divided into groups: I - 20 men without antiresorptive therapy; II - 20 men taking ibandronate 150 mg monthly, calcium and vitamin D (1000 mg/800 IU daily). The control group consisted of 20 men 54-65 years without OP. Microarchitectonics of the mandible was studied using cone-beam computed tomography and histomorphometry. Implants with bioactive surface based on sodium hydroxide (NaOH) were used. RESULTS: The results showed that the success of osseointegration is due to the qualitative parameters of the bone tissue of the perceived bed and the initial level of remodeling processes and does not depend on the conditioning of the implant surface NaOH. Comprehensive antiosteoporotic therapy with bisphosphonates and calcium supplementation with vitamin D leads to restoration of micro-alveolar part.

The treatment of ingrown nail: Chemical matricectomy with NAOH versus wedge resection.

Ingrown nail is a common problem seen in the dermatology clinics. The aim of this study is to compare the wedge resection method and chemical matricectomy with NaOH in terms of operation time, postoperative pain severity, postoperative drainage, recurrence rates, recovery time, and the effects of these two methods on Dermatology Quality of Life Index. This study included 60 patients. About 42 nail edges of 30 patients were treated with NaOH for chemical matricectomy and wedge resection was performed for 33 nail edges of 30 patients. Operation time for chemical matricectomy and wedge resection was an average of 7.66 ± 3.65 and 19.25 ± 5.54 min (p < .001). Recovery time was an average of 17.27 ± 14.22 days for chemical matricectomy and an average of 28.85 ± 17.03 days for wedge resection (p = .004). Recurrence was detected in 5.4% of the nail edges treated with chemical matricectomy and 3.6% of the nail edges treated with wedge resection (p = 1.000). Absence of differences for the recurrence rates between wedge resection method and chemical matricectomy method with NaOH shows that effectiveness of these approaches are similar. It seems that quite short operation and recovery times in the chemical matricectomy are the main advantage of the method.

Chemical matricectomy with sodium hydroxide: long-term follow-up results.

BACKGROUND: Chemical matricectomy with sodium hydroxide is a method being used successfully in the treatment of ingrown toenail. OBJECTIVE: In this study, it was aimed to evaluate long-term recurrence rates after chemical matricectomy using sodium hydroxide application of different durations. MATERIALS AND METHODS: Two hundred two patients with ingrown nail edges were treated with either 1-minute (Group 1) or 2-minute (Group 2) applications of sodium hydroxide matricectomy. All patients were followed for at least 2 years. RESULTS: Chemical matricectomy with sodium hydroxide was applied to a total of 585 nail edges of 202 cases. The overall recurrence rates in Group 1 and Group 2 were 6.4% and 7.1%, respectively, during the average 7.5-year follow-up period. No statistically significant differences were detected in terms of recurrence between the 2 groups (p = .73). CONCLUSION: Chemical matricectomy with sodium hydroxide is an easy method in the treatment of ingrown nails, with low morbidity and high success rates. There was no difference between 1-minute and 2-minute applications in terms of recurrence during the long-term follow-up. Chemical matricectomy with 1-minute application of sodium hydroxide showed high success in terms of long-term follow-up results.

Exploring postoperative outcomes for ingrown toenails. NaOH vs wedge resection techniques.

BACKGROUND: Ingrown (or ingrowing) toenail is a commonly used term for onychocryptosis, in which the nail becomes inserted into the lateral fold of the toe. The resulting effect on a person's health, well-being, and ability to work suggests the importance of clear treatment guidance, but little consensus exists. OBJECTIVE: To explore postoperative recovery after surgery for ingrown toenails using chemical (sodium hydroxide (NaOH)) or mechanical (wedge resection) matricectomy and thus contribute to understanding within the field on which to base treatment guidelines. METHODS: One hundred sixty-one procedures were undertaken, 94 using NaOH and 67 using wedge resection. Four measures of postoperative recovery were recorded: recurrence, infection, time to discharge, and number of postoperative visits. RESULTS: Patients treated with NaOH had lower rates of recurrence (p = .048) and infection (p = .03) than those treated with wedge resection, and time to discharge was shorter (p = .02), but they had more postoperative visits (p = .003). CONCLUSION: Low rates of recurrence and infection and short postoperative recovery time were found after both procedures, with a small advantage with treatment with NaOH. The authors argue for the value of clinical intervention using matricectomy in early stages to avoid complications resulting from granulation tissue growth.

Concentration and volume effects in thermochemical ablation in vivo: results in a porcine model.

PURPOSE: To explore the effects of volume and concentration in thermochemical ablation using an in vivo porcine model. METHODS: Twelve swine 60-75 kg were used in this institutionally approved study. A needle design prototype coaxial device for reagent injections and a thermocouple were inserted into surgically exposed liver. Simultaneously, an acid and base (acetic acid and NaOH) were injected at 4 mL/min based on a 3 × 3 matrix with concentration (5, 10, and 15 mol/L) and volume on the axes (total volumes of 1, 2, and 4 mL). Three animals (centre grid position) strengthened the statistical analysis. Each animal received four identical injections (total 48). Temperatures and heart rate were recorded. Livers were formalin-fixed after sacrifice. After sectioning, coagulation zones were analysed by two observers. Area and slice thickness were used to calculate the volume, surface area, and sphericity for each treatment. RESULTS: Coagulation volumes ranged from 2.95 ± 0.29 to 14.72 ± 1.42 mL with a maximum of 18.3 mL. Highest peak temperature was 105°C with temperatures ranging 43.5 ± 2.6°C to 91.0 ± 6.5°C. There was no association between conditions and sphericity or heart rate. CONCLUSIONS: The method can be used successfully to ablate tissue in vivo. By neutralising acid in situ and releasing heat and a salt, this technique improves considerably upon the use of acetic acid used alone. Peak temperatures exceeded accepted coagulation thresholds even if the only mechanism operating was hyperthermia. Reagent concentrations and volumes increased the amount of the coagulum but not in a linear fashion.

Effect of prion decontamination protocols on nickel-titanium rotary surfaces.

Decontamination of instruments is a prerequisite for their potential reuse but may affect surface integrity. Hence, the effect of prion removal protocols on 7 brands of nickel-titanium files was investigated. Baseline debris scores were determined under magnification after staining with van Gieson's solution. After shaping root canals in vitro, rotaries were mechanically and ultrasonically cleaned followed by immersion for 24 hours in 2 M sodium hydroxide (NaOH), 6 M CH(5)N(3), or 3% sodium hypochlorite (NaOCl); control files were stored dry. After sterilization, files were again stained and evaluated. Two of seven file brands demonstrated significantly higher baseline debris scores compared to final scores. Uniformly, debris could not be completely removed; there were no significant differences among groups. After immersion in NaOCl, 27.8% of instruments showed corrosion; however, no deterioration after immersion in the other solutions was found in the other groups. Regarding corrosion, no significant difference was found between brands. Based on these findings, single use of nickel-titanium rotaries appears beneficial.

A prospective randomized comparison of the Zadik procedure and chemical ablation in the treatment of ingrown toenails.

BACKGROUND: We present the results of a prospective randomized trial of the Zadik procedure versus chemical ablation by sodium hydroxide for the treatment of ingrowing toenails. METHODS: Thirty-eight patients had the Zadik procedure, and 45 patients had chemical ablation by sodium hydroxide. Mean followup was 12.45 months for the Zadik group and 11.69 months for the chemical ablation group. RESULTS: In the Zadik group, the average return to normal shoe-wear was 2.13 weeks and in the chemical ablation group 3.73 weeks. Average return to normal activity was 2.18 weeks for the Zadik group and 3.89 weeks for the chemical ablation group. The median number of dressings were 3 and 8 for the Zadik and chemical ablation groups, respectively. The pain score, using the visual analogue scale were not statistically significant between the two groups. The recurrence rates were 23 recurrences in the Zadik group (60.5%) and seven recurrences in the chemical ablation group (15.6%). CONCLUSION: The use of chemical ablation by sodium hydroxide in the treatment of ingrowing toenails shows statistically significant (p < 0.05) reduction in recurrence rates of ingrowing toenails compared to the Zadik procedure.

Dental practice implications of prion diseases.

This review article discusses dental practice implications of prion diseases, including Creutzfeldt-Jakob disease. The current universal precautions used for infection control in dentistry do not inactivate infectious prions. There is a theoretical, yet real risk of prion disease transmission through dental treatment, although the magnitude of that risk has not yet been determined. Medical, family, and travel histories can demonstrate the need for implementing improved levels of infection control. Best practices include the following: For certain cases, single-use disposable dental instruments should be used. Those instruments that are not disposable, should have a thorough physical cleaning, be soaked in hot 1N sodium hydroxide solution for 1 hour, and then autoclaved in a vacuum or porous-load autoclave at 134 degrees C to 138 degrees C for 18 to 20 minutes. Dental and other health care professionals need to understand prion diseases, and for best practice, consider implementing recommended changes to infection-control measures, since current practices do not destroy infectious prions.

Chemical matrixectomy for ingrown toenails: Is there an evidence basis to guide therapy?

Chemical matrixectomy for ingrown toenails is one of the most common surgical procedures performed on the foot. The procedure was first described in 1945 by Otto Boll, who discussed the use of phenol to correct ingrown toenails. In the years that followed, many variations of technique and method have been described. This article reviews the pertinent literature detailing chemical matrixectomies and advocates the use of an evidence basis for care.

Matricectomy and nail ablation.

Matricectomy refers to the complete extirpation of the nail matrix, resulting in permanent nail loss. Usually however, matricectomy is only partial, restricted to one or both lateral horns of the matrix. Nail ablation is the definitive removal of the entire nail organ. The most important common denominator in the successful matricectomy is the total removal or destruction of the matrix tissue. Matricectomy may be indicated for the management of onychauxis, onychogryphosis, congenital nail dystrophies, and chronic painful nail, such as recalcitrant ingrown toenail or split within the medial or lateral one-third of the nail.

Percutaneous injection of a low-concentration alkaline solution targeting hepatocellular carcinoma.

We developed a percutaneous low-concentration alkali injection therapy (PLAIT) targeting hepatocellular carcinoma (HCC), and compared the necrotic areas in the livers of rats that had received PLAIT [an alkaline solution of sodium hydroxide (NaOH)] with those that had received percutaneous ethanol injection therapy (PEIT) and percutaneous acetic acid injection therapy (PAIT). The necrotic area increased with increasing concentrations of NaOH solution. The survival rate of rats was 100% up to a concentration of 4 N; however, the rate dropped below 80% with concentrations over 5 N. Also, at a concentration of 2 N, the necrotic area increased with increasing quantities from 0.01 ml to 0.1 ml. PLAIT using 0.05 ml of 2 N NaOH was 1.56 times more effective than PEIT using 0.05 ml of 99.5% ethanol, and 63.33% less effective than PAIT using 0.05 ml of 50% acetic acid. However, the survival rate after PAIT was 50%, while that after PLAIT was 100%. Histopathological observation of normal rat livers after injection of 2 N NaOH at a volume of 0.05 ml showed that the tissue necrosis spread radially from the site immediately after injection by PLAIT, but necroses were not found in other organs. We conclude that PLAIT has promise as a new form of local therapy for HCC.

Prueba de la desnaturalización alcalina de la hemoglobina en obstetricia / Alcaline denaturation test of the hemoglobin in obstetrics

Evaluar prospectivamente la utilidad de la prueba de la desnaturalización alcalina con hidróxido de sodio en la identificación de la hemoglobina fetal y del adulto. El fundamento de la prueba es la propiedad de la hemoglobina fetal de ser resistente a la desnaturalización alcalina y a la fragilidad de la hemoglobina del adulto. Se recolectaron 100 muestras de sangre del cordón umbilical y 100 de mujeres no embarazadas. Se prepararon hemolizados que fueron sometidos a concentración variable de hidróxido de sodio 0,2 N; 0,4 N; 0,6 N; y 0,8 N para determinar cúal era la de mayor utilidad discriminativa. A un grupo de 80 hemolizados, codificados y aleatorios (40 adulto y 40 fetal), se sometieron a identificación de manera ciega con observadores voluntarios. Hospital "Dr. Adolfo Prince Lara", Puerto Cabello, Edo. Carabobo. El hidróxido de sodio 0,2 N fue la concentración que más evidentemete deslindó las hemoglobinas estudiadas al valorar el tiempo y cambio de color inducido (p< 0,001). Todos los hemolizados adultos y fetales probados en ensayos ciegos, fueron identificados correctamente al emplear hidróxido de sodio 0,2 N. La prueba de desnaturalización de la hemoglobina con hidróxido de sodio al 0,2 N es una prueba sencilla, rápida, económica y segura en la identificación de la hemoglobina fetal y la adulta

Improved healing with a collagen-alginate dressing in the chemical matricectomy.

A prospective clinical trial was conducted to evaluate the efficacy of a collagen-alginate wound dressing in the postoperative management of chemical matricectomies. The study involved 20 patients and 23 separate procedures. The collagen-alginate-dressing treatment group had an average healing time of 24.4 days, compared with 35.8 days for the control group, which received treatment consisting of soaks and daily dressing changes (P < .05). The authors suggest that using a collagen-alginate wound dressing in the postoperative management of chemical matricectomies will shorten healing time, thus reducing infection rates and increasing patient compliance and satisfaction.

Agentes transmisibles infecciosos no convencionales (ATNC). Parte II: priones / Non-conventional infectious transmissible agents. Part II: prions

La incidencia de enfermedades producidas por agentes infecciosos transmisibles no convencionales (ATNC), es de un caso por millón de personas por año, en los cinco continentes. Se sospecha que la transmisión puede ser por transfusiones, tratamientos dentales e implante óseos. Los priones son extraordinariamente resistentes a los métodos de desinfección y a los procedimientos de esterilización habituales. Pero también, resultan resistentes a la ebullición, las radiaciones ionizantes, alcohol 70 por ciento más formaldehído, glutaraldehído, formaldehído al 4 por ciento y la formalina al 10 por ciento, usada para la preservación de biopsias. Pueden ser inactivados por: calos húmedo a 132 grados C, 30-60 min; hidróxido de sodio (1 N) a temperatura ambiente durante 60 min. seguido de autoclavado a 121 grados C, 30 min. El hipoclorito reduce pero no elimina completamente la transmisibilidad, mientras que el hidróxido de sodio (1 N) es más efectivo y menos corrosivo. Futuros conocimientos de la biología molecular y de la patogénesis de las enfermedades de las que son responsable, irán aclarando dudas (AU)

Agentes transmisibles infecciosos no convencionales (ATNC). Parte II: priones / Non-conventional infectious transmissible agents. Part II: prions

La incidencia de enfermedades producidas por agentes infecciosos transmisibles no convencionales (ATNC), es de un caso por millón de personas por año, en los cinco continentes. Se sospecha que la transmisión puede ser por transfusiones, tratamientos dentales e implante óseos. Los priones son extraordinariamente resistentes a los métodos de desinfección y a los procedimientos de esterilización habituales. Pero también, resultan resistentes a la ebullición, las radiaciones ionizantes, alcohol 70 por ciento más formaldehído, glutaraldehído, formaldehído al 4 por ciento y la formalina al 10 por ciento, usada para la preservación de biopsias. Pueden ser inactivados por: calos húmedo a 132 grados C, 30-60 min; hidróxido de sodio (1 N) a temperatura ambiente durante 60 min. seguido de autoclavado a 121 grados C, 30 min. El hipoclorito reduce pero no elimina completamente la transmisibilidad, mientras que el hidróxido de sodio (1 N) es más efectivo y menos corrosivo. Futuros conocimientos de la biología molecular y de la patogénesis de las enfermedades de las que son responsable, irán aclarando dudas