Dental implications in oral cancer patients

Objectives. A study is made of the dental implications of oral cancer, with a view to avoiding the complications that appear once oncological treatment is started. Patients and Methods. The study comprised a total of 22 patients diagnosed with oral cancer according to clinical and histological criteria in the Service of Maxillofacial Surgery (Dental Clinic of the University of Barcelona, Spain) during the period 1996-2005, and posteriorly treated in different hospital centers in Barcelona. Results. Of the 22 patients diagnosed with oral cancer in our Service, the present study finally analyzed the 12 subjects who reported for the dental controls. As regards the remaining 10 patients, 5 had died and 5 could not be located; these subjects were thus excluded from the analysis. All of the smokers had abandoned the habit. The most common tumor location was the lateral margin of the tongue. None of the patients visited the dentist regularly before the diagnosis of oral cancer. T1N0M0 was the most common tumor stage. Surgery was carried out in 50% of the cases, while 8.4% of the patients received radiotherapy and 41.6% underwent surgery with postoperative radiotherapy. In turn, 66.6% of the patients reported treatment sequelae such as dysgeusia, xerostomia or speech difficulties, and one patient suffered osteoradionecrosis. Forty-one percent of the patients did not undergo regular dental controls after cancer treatment. As regards oral and dental health, 16.6% presented caries, and 50% had active periodontal disease. Conclusions. Protocols are available for preventing the complications of oral cancer treatment, and thus for improving patient quality of life. However, important shortcomings in the application of such protocols on the part of the public health authorities make it difficult to reach these objectives

Holographic optical tweezers combined with back-focal-plane displacement detection

A major problem with holographic optical tweezers (HOTs) is their incompatibility with laser-based position detection methods, such as back-focal-plane interferometry (BFPI). The alternatives generally used with HOTs, like high-speed video tracking, do not offer the same spatial and temporal bandwidths. This has limited the use of this technique in precise quantitative experiments. In this paper, we present an optical trap design that combines digital holography and back-focal-plane displacement detection. We show that, with a particularly simple setup, it is possible to generate a set of multiple holographic traps and an additional static non-holographic trap with orthogonal polarizations and that they can be, therefore, easily separated for measuring positions and forces with the high positional and temporal resolutions of laser-based detection. We prove that measurements from both polarizations contain less than 1% crosstalk and that traps in our setup are harmonic within the typical range. We further tested the instrument in a DNA stretching experiment and we discuss an interesting property of this configuration: the small drift of the differential signal between traps.

Glibenclamide enhances neurogenesis and improves long-term functional recovery after transient focal cerebral ischemia

Glibenclamide is neuroprotective against cerebral ischemia in rats. We studied whether glibenclamide enhances long-term brain repair and improves behavioral recovery after stroke. Adult male Wistar rats were subjected to transient middle cerebral artery occlusion (MCAO) for 90 minutes. A low dose of glibenclamide (total 0.6mg) was administered intravenously 6, 12, and 24 hours after reperfusion. We assessed behavioral outcome during a 30-day follow-up and animals were perfused for histological evaluation. In vitro specific binding of glibenclamide to microglia increased after pro-inflammatory stimuli. In vivo glibenclamide was associated with increased migration of doublecortin-positive cells in the striatum toward the ischemic lesion 72 hours after MCAO, and reactive microglia expressed sulfonylurea receptor 1 (SUR1) and Kir6.2 in the medial striatum. One month after MCAO, glibenclamide was also associated with increased number of NeuN-positive and 5-bromo-2-deoxyuridine-positive neurons in the cortex and hippocampus, and enhanced angiogenesis in the hippocampus. Consequently, glibenclamide-treated MCAO rats showed improved performance in the limb-placing test on postoperative days 22 to 29, and in the cylinder and water-maze test on postoperative day 29. Therefore, acute blockade of SUR1 by glibenclamide enhanced long-term brain repair in MCAO rats, which was associated with improved behavioral outcome.

El sistema dental y su importancia en el estudio de la evolución humana: revisión bibliográfica.

La dentición ha sido durante mucho tiempo una de las estructuras biológicas mejor estudiadas, esta singularidad radica en su resistencia al paso del tiempo. El sistema dental ofrece una posibilidad incomparable para comprender mejor el origen y filogénesis de los vertebrados, entre ellos el hombre. Esta investigación, a través de una revisión bibliográfica, explora cuatro aspectos del sistema dental, como son: Su origen, el aspecto biológico, la utilidad de los rasgos dentales en los análisis poblacionales, y finalmente, intenta precisar las bases genéticas de los dientes. Con respecto a este último, lo fundamental no estaría sólo en la descripción morfológica del diente, sino el porqué de su morfología, es decir, porqué son lo que son. Por lo tanto, se puede indagar: ¿porqué se producen diferentes variedades morfológicas dentro de nuestra especie?, entre otras interrogantes

El sistema dental y su importancia en el estudio de la evolución humana: revisión bibliográfica.

La dentición ha sido durante mucho tiempo una de las estructuras biológicas mejor estudiadas, esta singularidad radica en su resistencia al paso del tiempo. El sistema dental ofrece una posibilidad incomparable para comprender mejor el origen y filogénesis de los vertebrados, entre ellos el hombre. Esta investigación, a través de una revisión bibliográfica, explora cuatro aspectos del sistema dental, como son: Su origen, el aspecto biológico, la utilidad de los rasgos dentales en los análisis poblacionales, y finalmente, intenta precisar las bases genéticas de los dientes. Con respecto a este último, lo fundamental no estaría sólo en la descripción morfológica del diente, sino el porqué de su morfología, es decir, porqué son lo que son. Por lo tanto, se puede indagar: ¿porqué se producen diferentes variedades morfológicas dentro de nuestra especie?, entre otras interrogantes

Computer-aided system for morphometric mandibular index computation (Using dental panoramic radiographs)

Objective: We propose and validate a computer aided system to measure three different mandibular indexes: cortical width, panoramic mandibular index and, mandibular alveolar bone resorption index. Study Design: Repeatability and reproducibility of the measurements are analyzed and compared to the manual estimation of the same indexes. Results: The proposed computerized system exhibits superior repeatability and reproducibility rates compared to standard manual methods. Moreover, the time required to perform the measurements using the proposed method is negligible compared to perform the measurements manually. Conclusions: We have proposed a very user friendly computerized method to measure three different morphometric mandibular indexes. From the results we can conclude that the system provides a practical manner to perform these measurements. It does not require an expert examiner and does not take more than 16 seconds per analysis. Thus, it may be suitable to diagnose osteoporosis using dental panoramic radiographs.

Studies on the characterization of dental whitening process by using both hyperspectral imaging and colorimeter techniques

A beautiful smile is directly related with white teeth. Nowadays oral care has increased and developed processes for beautiful smiles. Dental bleaching is frequently used in odontology, not just for health care also for aesthetic treatment. With the possibility of teeth bleaching, now the importance is in, how white the tooth is? Because color is relate to an individual perception. In order to assets teeth correct color identification has been developed many color guides, models, spaces and analytical methods. Spite all of these useful tools the color interpretation depends on environmental factors, position of the sample in the data acquisition and most importantly the instrument sensitivity. The commons methods have proved to be useful. They are easy to handle, some are portable but they do not have a high sensitivity. The present work is based on the integration of a new analytical technique for color acquisition. High spectral Image (HSI) is able to performed image analysis with high quality and efficiency. HSI is used in many fields and we used it for color image analysis within the bleaching process. The main comparison was done with the HSI and the colorimeter through the processes of two different bleaching protocols. The results showed that HSI has higher sensitivity than the colorimeter. During the analysis the dental surface with the HSI we were able to notice surface changes. These changes were analyzed by roughness studies.

Prevalencia de la infección tuberculosa y por el VIH en los usuarios de un programa de reducción de riesgos para usuarios de drogas por vía parenteral (UDVP)

FUNDAMENTO: Determinar la prevalencia de la infección tuberculosa y por el VIH, así como los factores asociados, en la población de usuarios del programa de reducción de riesgos de la ciudad de Lleida. MÉTODOS: La muestra la formaron los nuevos usuarios del programa en el período abril-junio de 1996, entre los los cuales se realizó un cuestionario para la recogida de datos de las variables: edad, sexo, resultado de la prueba de la tuberculina, vacunación BCG, conocimiento de la serología frente al VIH, ingreso en prisión y años de consumo de heroína. Se calculó la prevalencia de la infección tuberculosa y por el VIH, con el intervalo de confianza (IC) del 95%. La asociación de ambas variables con el resto de variables del estudio se determinó mediante la odds ratio (OR) y su IC del 95% . RESULTADOS: Acudieron 150 pacientes diferentes, de los cuales 45 eran nuevos usuarios. De ellos, el 80,0% eran varones, con una edad media de 31,1 años. La prevalencia de la coinfección fue del 8,9% (IC 95% 2,8-22,1). La prevalencia de la infección tuberculosa fue de 27,3% (IC 95% 12,4-43,0), siendo superior en los que tenían antecedentes de ingreso en prisión (OR=3,4; IC 95% 0,5-27,4). La prevalencia de la infección por el VIH fue del 36,1% (IC 95% 21,3-53,8), siendo superior en los que tenían una antigüedad, en el consumo de heroína, superior a los 11 años ( OR = 7,3; IC 95% 1,0-65,9). CONCLUSIONES: El antecedente de ingreso en prisión es el principal factor de riesgo de la infección tuberculosa. Los años de consumo se asocian con la infección por el VIH, especialmente a partir de los 11 años. Los programas de reducción de riesgos de nuestro país deberían realizar actividades de control de la infección tuberculosa y por VIH.

Morbilidad de la extracción de los terceros molares en pacientes entre los 12 y 18 años de edad

Objetivo: El propósito de este estudio fue analizar la incidencia de complicaciones después de la extracción quirúrgica de los terceros molares en pacientes de 12 a 18 años de edad. Pacientes y método: Se realizó un estudio retrospectivo de 390 extracciones quirúgicas de terceros molares superiores e inferiores en 173 pacientes en edades comprendidas entre los 12 y 18 años de edad, intervenidos bajo anestesia locorregional en el año 2000 en el Máster de Cirugía Bucal e Implantología Bucofacial de la Universidad de Barcelona. Los pacientes fueron divididos en tres grupos (A: 12-14 años, B:15-16 años, C: 17-18 años). Se registró la edad y el sexo del paciente, el motivo de la extracción, el grado de desarrollo dentario, la posición, la angulación y la inclusión del tercer molar. Finalmente se valoró la asociación entre dichas variables y la aparición de complicaciones postoperatorias. Resultados: La mayoría de los pacientes intervenidos fueron del sexo femenino (66,9%), y el grupo de edad en la que se realizó el mayor número de extracciones (62,8%) fue en el grupo C (17-18 años). El principal motivo de extracción fue la indicación por parte del ortodoncista (40,5%), seguido por la indicación profiláctica (39,5%). La presencia de clínica fue el motivo de extracción en un 20% de los casos. Se observó una incidencia del 15,6% de complicaciones postoperatorias tras la extracción de 390 terceros molares. En el grupo A el riesgo de complicaciones fue de 17,4%, en el grupo B de 19% y en el grupo C de 13,7%. Todas las complicaciones fueron reversibles y de corta duración como el dolor y la inflamación persistente, la infección, el trismo y la equimosis. Se presentó un caso de parestesia del nervio dentario inferior y un caso de parestesia del nervio lingual que remitieron a los 2 meses y al mes respectivamente. Conclusiones: este estudio demuestra que no hay diferencias significativas en las complicaciones observadas entre los tres grupos de edad, y por lo general, éstas son leves y reversibles. Se observó una mayor tendencia de complicaciones en las mujeres y el porcentaje de complicaciones aumenta cuanto menor es el espacio disponible para la erupción

Diet-related buccal dental microwear patterns in central african pygmy foragers and bantu-speaking farmer and pastoralist populations.

Pygmy hunter-gatherers from Central Africa have shared a network of socioeconomic interactions with non-Pygmy Bantu speakers since agropastoral lifestyle spread across sub-Saharan Africa. Ethnographic studies have reported that their diets differ in consumption of both animal proteins and starch grains. Hunted meat and gathered plant foods, especially underground storage organs (USOs), are dietary staples for pygmies. However, scarce information exists about forager-farmer interaction and the agricultural products used by pygmies. Since the effects of dietary preferences on teeth in modern and past pygmies remain unknown, we explored dietary history through quantitative analysis of buccal microwear on cheek teeth in well-documented Baka pygmies. We then determined if microwear patterns differ among other Pygmy groups (Aka, Mbuti, and Babongo) and between Bantu-speaking farmer and pastoralist populations from past centuries. The buccal dental microwear patterns of Pygmy hunter-gatherers and non-Pygmy Bantu pastoralists show lower scratch densities, indicative of diets more intensively based on nonabrasive foodstuffs, compared with Bantu farmers, who consume larger amounts of grit from stoneground foods. The Baka pygmies showed microwear patterns similar to those of ancient Aka and Mbuti, suggesting that the mechanical properties of their preferred diets have not significantly changed through time. In contrast, Babongo pygmies showed scratch densities and lengths similar to those of the farmers, consistent with sociocultural contacts and genetic factors. Our findings support that buccal microwear patterns predict dietary habits independent of ecological conditions and reflect the abrasive properties of preferred or fallback foods such as USOs, which may have contributed to the dietary specializations of ancient human populations.

Evaluation of the indication for surgical extraction of third molars according to the oral surgeon and the primary care dentist. Experience in the Master of Oral Surgery and Implantology at Barcelona University Dental School

Introduction: Third molar extraction is the most frequent procedure in oral surgery. The present study evaluates the indication of third molar extraction as established by the primary care dentist (PCD) and the oral surgeon, and compares the justification for extraction with the principal reason for patient consultation. Patients and method: A descriptive study was made of 319 patients subjected to surgical removal of a third molar in the context of the Master of Oral Surgery and Implantology (Barcelona University Dental School, Barcelona, Spain) between July 2004 and March 2005. The following parameters were evaluated: sex, age, molar, type of impaction, position according to the classifications of Pell and Gregory and of Winter, and the reasons justifying extraction. Results: The lower third molars were the most commonly extracted molars (73.7%). A total of 69.6% of the teeth were covered by soft tissues only. Fifty-six percent of the lower molars corresponded to Pell and Gregory Class IIB, while 42.1% were in the vertical position. The most common reason for patient reference to our Service of Oral Surgery on the part of the PCD was prophylactic removal (51.0% versus 46.1% in the case of the oral surgeon). Discussion and conclusions. Our results show prophylaxis to be the principal indication of third molar extraction, followed by orthodontic reasons. Regarding third molars with associated clinical symptoms or signs, infectious disease-including pericoronitis- was the pathology most often observed by the oral surgeon, followed by caries. This order of frequency was seen to invert in the case of third molars referred for extraction by the PCD. A vertical position predominated among the third molars with associated pathology

Endosseous dental implant fractures an analysis of 21 cases

Implant fracture is an infrequent cause of implant failure. The present study evaluates 21 fractured implants, with an analysis of patient age and sex, the type, length and diameter of the implant, positioning in the dental arch, the type of prosthetic rehabilitation involved, the number of abutments and pontics, the presence or absence of distal extensions or cantilevers, and loading time to fracture. Implant fracture was more common in males than in females (15:4), and the mean patient age was 56.9 years. Most cases (n = 19) corresponded to implant-supported fixed prostheses - 16 with cantilevers of different lengths- while only two fractured implants were supporting overdentures instead of fixed prostheses. The great majority of fractured implants (80.9%) were located in the molar and premolar regions, and most fractured within 3-4 years after loading. It is important to know and apply the measures required to prevent implant fracture, and to seek the best individualized solution for each case - though complete implant removal is usually the treatment of choice

Diagonal ear lobe crease and atherosclerosis: a review of the medical literature and dental implications

In Spain a significant number of individuals die from atherosclerotic disease of the coronary and carotid arteries without having classic risk factors and prodromal symptoms. The diagonal ear lobe crease (DELC) has been characterized in the medical literature as a surrogate marker which can identify high risk patients having occult atherosclerosis. This topic however has not been examined in either the medical or dental literature emanating from Spain. The majority of clinical, angiography and postmortem reports support the premise that DELC is a valuable extravascular physical sign able to distinguish some patients at risk of succumbing to atherosclerosis of the coronary arteries. A minority of studies have however failed to support this hypothesis. More recently reports using B mode ultrasound have also linked DELC to atherosclerosis of the carotid artery and another report has related DELC to the presence of calcified carotid artery atheromas on panoramic radiographs. DELC is readily visible during head and neck cancer screening examinations. In conjunction with the patient"s medical history, vital signs, and panoramic radiograph, the DELC may assist in atherosclerotic risk assessment

Computer-aided system for morphometric mandibular index computation (Using dental panoramic radiographs)

Objective: We propose and validate a computer aided system to measure three different mandibular indexes: cortical width, panoramic mandibular index and, mandibular alveolar bone resorption index. Study Design: Repeatability and reproducibility of the measurements are analyzed and compared to the manual estimation of the same indexes. Results: The proposed computerized system exhibits superior repeatability and reproducibility rates compared to standard manual methods. Moreover, the time required to perform the measurements using the proposed method is negligible compared to perform the measurements manually. Conclusions: We have proposed a very user friendly computerized method to measure three different morphometric mandibular indexes. From the results we can conclude that the system provides a practical manner to perform these measurements. It does not require an expert examiner and does not take more than 16 seconds per analysis. Thus, it may be suitable to diagnose osteoporosis using dental panoramic radiographs