In vitro performance of a pen-type laser fluorescence device and bitewing radiographs for approximal caries detection in permanent and primary teeth.

Aim: To evaluate the performance of a pen‑type laser fluorescence device (DIAGNOdent 2190; LFpen, KaVo, Germany) and bitewing radiographs (BW) for approximal caries detection in permanent and primary teeth. Materials and Methods: A total of 246 anterior approximal surfaces (102 permanent and 144 primary) were selected. Contact points were simulated using sound teeth. Two examiners assessed all approximal surfaces using LFpen and BW. The teeth were histologically assessed for the reference standard. Optimal cut‑off limits were calculated for LFpen for primary and permanent teeth. Sensitivity, specificity, accuracy and area under the receiver operating characteristic curve (Az) were calculated for D1 (enamel and dentin lesions) and D3 (dentin lesions) thresholds. The reproducibility was assessed by intraclass correlation coefficient (ICC) and Cohen’s weighted kappa values. Results: For permanent teeth, the LFpen cut‑off were 0–27 (sound), 28–33 (enamel caries) and >33 (dentin caries). For primary teeth, the LFpen cut‑off were 0–7 (sound), 8–32 (enamel caries) and >32 (dentin caries). The LFpen presented higher sensitivity values than BW for primary teeth (0.58 vs. 0.32 at D1 and 0.80 vs. 0.47 at D3) and permanent teeth (0.80 vs. 0.57 at D1 and 0.94 vs. 0.51 at D3). Specificity did not show a significant difference between the methods. Rank correlations with histology were 0.59 and 0.83 (LFpen) and 0.36 and 0.70 (BW) for primary and permanent teeth, respectively, considering all lesions. ICC values for LFpen were 0.71 (inter) and 0.86 (intra) for permanent teeth and 0.94 (inter) and 0.90/0.99 for primary teeth. Kappa values for BW were 0.69 (inter) and 0.68/0.90 (intra) for permanent teeth and 0.64 (inter) and 0.89/0.89 for primary teeth. Conclusion: LFpen presented better reproducibility for primary and permanent teeth and higher accuracy in detecting caries lesions at D1 threshold than BW for permanent teeth. LFpen should be used as an adjunct method for approximal caries detection.

Usos y fundamentos del láser en periodoncia e implantología oral / Uses and fundamentals of laser in periodontics and oral implantology

El primer dispositivo láser fue desarrollado por Maiman en 1960. Desde entonces, el láser es ampliamente usado en medicina y cirugía, debido a su capacidad de emitir energía altamente concentrada y controlable sobre los tejidos a ser tratados. Para obtener el efecto biológico deseado, la energía debe absorberse en los tejidos y, al ser transformada en calor, se consiguen distintos efectos, dependiendo de la temperatura a la que se eleve el tejido. En caso de exceso de neergía láser aplicada, se elevará la temperatura del tejido por sobre los 200º C y se llegará a la carbonización y, en consecuencia, al daño tisular. Por esta razón, el clínico debe controlar los parámetros de energía, el diámetro del rayo y el tiempo o la duración de la exposición, para obtener un resultado satisfactorio, teniendo en cuenta que el rango de ablación varía con la composición y la estructura del sitio quirúrgico. Es muy importante tener en cuenta que diferentes longitudes de onda tienen diferentes coeficientes de absorción en los diferentes tejidos. Los láseres más utilizados en odontología para el desarrollo de tratamientos periodontales, incluyendo cirugía periodontal, poseen longitudes de onda que pertenecen al rango visible e invisible del espectro electromagnético. Podemos mencionar el láser de Erbium:YAG (2.940 nm), dióxido de carbono (10.600 nm), Nd:YAG (1064 nm), diodo (810-980 nm) y el láser e argón, con dos longitudes de onda (488 nm, de color azul, y 514 nm, verde azulada). Los láseres de argón, diodo y Nd:YAG tienen alta afinidad por componentes de la sangre y tejidos pigmentados y, por consiguiente, muy buena absorción en ellos. Los láseres de erbium:YAG y dióxido de carbono son altamente absorbidos por el agua, principal componente de los tejidos blandos. La razón por la que no existe un dispositivo láser que sea 100 por ciento eficiente en todos los tejidos, se debe a la composición del tejido y al tipo de interacción física de la luz.

Manual stapedotomy still holds good in the era of laser.

Context: In the present era of stapedotomy, there is an inevitable role for laser. But the conventional technique with manual burr still has its own merits in various settings such as usage in resource poor setting in developing countries and avoidance of laser hazards. AIMS: To evaluate the audiometric outcomes after manual stapedotomy. Settings and Design: The present study was retrospective record-based study. Patients who have been diagnosed otosclerosis and those who were not willing for surgery with laser, but gave consent for manual stapedotomy were included for the study. Materials and Methods: Preoperatively, and at each subsequent post-operative follow-up visits, patients were required to undergo a pure-tone audiogram. The air-bone gaps at the end of 6 months were used for final analysis. Statistical Analysis Used: Data was analyzed with using Statistical Package for Social Sciences (SPSS) version 12 (Chicago, IL, USA). Descriptive frequency distributions, mean, standard deviation of audiometric data were calculated. The paired t test was done to see the improvement in the air bone gap post-operatively. Results: The mean age of presentation is 32.2 years. Overall, the male:female ratio was found to be 1:1.2. Post-operative air bone closure to 15 decibels was obtained in 80% of patients. There was no significant correlation between the pre-operative hearing loss and post-operative gain, age, and gender of distribution of focus. Conclusions: The post-operative hearing after stapedotomy has been remarkable in all the patients even with manual burr. There were no major vestibular complications in any of these patients. The study has shown that the significant post-operative hearing results can be still achieved with meticulous surgery by an experienced surgeon with manual burr in the present laser era.

Endonasal CO2-laser-assisted dacryocystorhinostomy

The laser is once again poised to revolutionize ophthalmology, this time in the field of lacrimal surgery. At many centers, transnasal laser-assisted dacryocystorhinostomy is currently being performed and evaluated as a less invasive method for lacrimal bypass surgery than the traditional method. We have performed this new operation on ten patients. Advantages include avoidance of a cutaneous scar, reduction of surgical trauma and bleeding, minimal postoperative pain, and a shortened period of recovery. The surgical success rate of 90% is comparable to that of conventional dacryocystorhinostomy

Current concepts in diabetic macular edema

Edema of the macula in diabetic patients is a frequent component of diabetic retinopathy, as well as a leading cause of loss of vision in this common disorder. The disease macular edema [ME] is subdivided into focal and diffuse. Many factors, both local and systemic, may contribute to the formation of diabetic ME. Several studies have shown that photocoagulation treatment of eyes with diabetic ME decreases the risk of visual loss. Early detection of asymptomatic diabetic patients with clinically significant ME is important for effective treatment. The results of the Early Treatment Diabetic Retinopathy Study [ETDRS] suggest that clinical signs of ME, rather than deterioration of visual acuity, are the important criteria in deciding whether and when to apply focal photocoagulation in persons with diabetes

Retinal vasculitis with secondary proliferative changes in wegener's granulomatosis

Wegener's granulomatosis is characterized by a chronic, focal, necrotizing, and granulomatous vasculitis. Retinal vasculitis is well-known ocular complication of this mysterious disease. We report a case of Wegener's granulomatosis with characteristic systemic involvement, and where the diagnosis was confirmed by histopathologic evaluation of a nasal mucosal biopsy specimen. Almost seven years after initial presentation, the disease being controlled by cyclophosphamide and steroid therapy, peripheral vasculitis, complicated by neovascular tufts at the border between perfused and non-perfused retina, was discovered in the patient's right eye. Peripheral scatter argon laser photocoagulation applied to the ischemic retina was followed by regression of the neovascular tufts

Aplicaciones del rayo laser en endoscopía digestiva / Use of laser in digestive endoscopy

La aplicación endoscópica del Nd: Yag laser en el control del sagrado digestivo está adquiriendo especial significado en un seleccionado grupo de pacientes con alto riesgo. Lesiones mucosas, como los pólipos benignos y malformaciones vasculares pueden ser tratadas exitosamente. En lesiones gastrointestinales obstructivas malignas avanzadas e inoperables, que son accesibles a la visión endoscópica, la cirugía por laser es extremadamente útil como procedimiento paliativo. Los resultados en early cáncer gástrico, endoscópicamente vaporizados son estimulantes. El sistema laser es caro y requiere complejas conexiones de agua y electricidad, además de la asistencia de un técnico competente. Se trata de resolver estos problemas que pueden cambiar dramáticamente el futuro de la endoscopía terapéutica del laser