RESUMEN
The introduction of optimized nanoheaters, which function as theranostic agents integrating both diagnostic and therapeutic processes, holds significant promise in the medical field. Therefore, developing strategies for selecting and utilizing optimized plasmonic nanoheaters is crucial for the effective use of nanostructured biomedical agents. This work elucidates the use of the Joule number (Jo) as a figure of merit to identify high-performance plasmonic theranostic agents. A framework for optimizing metallic nanoparticles for heat generation was established, uncovering the size dependence of plasmonic nanoparticles optical heating. Gold nanospheres (AuNSs) with a diameter of 50 nm and gold nanorods (AuNRs) with dimensions of 41×10 nm were identified as effective nanoheaters for visible (530 nm) and infrared (808 nm) excitation. Notably, AuNRs achieve higher Jo values than AuNSs, even when accounting for the possible orientations of the nanorods. Theoretical results estimate that 41×10 nm gold nanorods have an average Joule number of 80, which is significantly higher compared to larger rods. The photothermal performance of optimal and suboptimal nanostructures was evaluated using photoacoustic imaging and photothermal therapy procedures. The photoacoustic images indicate that, despite having larger absorption cross-sections, the large nanoparticle volume of bigger particles leads to less efficient conversion of light into heat, which suggests that the use of optimized nanoparticles promotes higher contrast, benefiting photoacoustic-based procedures in diagnostic applications. The photothermal therapy procedure was performed on S180-bearing mice inoculated with 41×10 nm and 90×25 nm PEGylated AuNRs. Five minutes of laser irradiation of tumor tissue with 41×10 nm produced an approximately 9.5% greater temperature rise than using 90×25 AuNRs in the therapy trials. Optimizing metallic nanoparticles for heat generation may reduce the concentration of the nanoheaters used or decrease the light fluence for bioscience applications, paving the way for the development of more economical theranostic agents.
RESUMEN
Obstructive sleep apnoea (OSA) results from the recurrent collapse of the upper airway during sleep. Nasal abnormalities influence the stability of the pharynx. The aim of this study was to evaluate the volumetric and anatomical changes of the nasal cavity in patients with OSA. The Nasal Obstruction Symptom Evaluation (NOSE) scale was used to grade nasal obstruction. Sleep-related breathing disorders were evaluated by polysomnography. The nasal airway volume was obtained from computed tomography scans through volumetric reconstruction of the nasal airway. Alterations to the nasal anatomy were identified by nasal fibre-optic endoscopy. Ninety-four patient charts were analyzed. The final sample comprised 32 patients with severe OSA, 16 with moderate OSA, 23 with mild OSA, and 20 without OSA. Three groups were established based on nasal obstruction and OSA. The groups were compared for nasal airway volume (P=0.464) and body mass index (P=0.001). The presence of nasal septum deviation and inferior turbinate hypertrophy were related to the NOSE score (P=0.05 for both), apnoea-hypopnoea index (P=0.03 and P=0.05, respectively), and nasal airway volume (P=0.71 and P=0.78, respectively). In this nasal airway evaluation of OSA patients, the presence of sites of obstruction was correlated with the severity of OSA; this was not the case for the evaluation of the nasal airway volume dimensions.
Asunto(s)
Endoscopía/métodos , Obstrucción Nasal/diagnóstico por imagen , Obstrucción Nasal/fisiopatología , Apnea Obstructiva del Sueño/diagnóstico por imagen , Apnea Obstructiva del Sueño/fisiopatología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Estudios Transversales , Electrocardiografía , Electroencefalografía , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Índice de Severidad de la EnfermedadRESUMEN
The aim of this study was to evaluate the survival of single dental implants subjected to immediate function. Twelve patients with edentulous areas in the posterior mandible were included in the study. All received at least one regular platform dental implant (3.75mm×11mm or 3.75mm×13mm). Clinical and radiographic parameters were evaluated. The survival rate after 12 months was 83.3%. The implants showed no clinical mobility, had implant stability quotient values (ISQ; Osstell) around 70, bone loss of up to 2mm, and a probing depth of ≤3mm. Although the posterior mandible is an area in which the immediate loading of dental implants should be performed with caution, this treatment presented a good success rate in the present study sample.
Asunto(s)
Implantes Dentales de Diente Único , Carga Inmediata del Implante Dental , Mandíbula/cirugía , Adulto , Diseño de Prótesis Dental , Retención de Prótesis Dentales , Fracaso de la Restauración Dental , Femenino , Humanos , Arcada Parcialmente Edéntula/cirugía , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del TratamientoRESUMEN
Transverse maxillary deficiency is commonly found in patients with sleep apnea and is also related to abnormal breathing patterns. Maxillary expansion procedures promote widening of the nasal floor and reduce the resistance to airflow, and have a positive influence on nasopharynx function. In order to evaluate volume changes in the upper airway, 15 adult patients with transverse maxillary deficiency underwent surgically assisted rapid maxillary expansion (RME) until a slight overcorrection of the crossbite was obtained. Cone beam computed tomography (CBCT) volumetric images were obtained at three predefined time points. The mean age of the patients was 30.2 (±7.4) years; nine were females and six were males. The area, volume, and the smallest transverse section area of the airway were assessed using Dolphin Imaging 3D software. Statistical comparisons were made of the changes between time periods. No statistically significant differences were found for volume or area. However a significant difference was found between the preoperative and immediate postoperative smallest transverse section area (P<0.05). Maxillary expansion, as an isolated procedure, does not result in a statistically significant improvement in the airway dimensions and results in an inferior relocation of the smallest transverse section area.
Asunto(s)
Maxilar/diagnóstico por imagen , Maxilar/cirugía , Cavidad Nasal/diagnóstico por imagen , Nasofaringe/diagnóstico por imagen , Orofaringe/diagnóstico por imagen , Técnica de Expansión Palatina , Adulto , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Masculino , Maxilar/anomalías , Cavidad Nasal/anatomía & histología , Nasofaringe/anatomía & histología , Orofaringe/anatomía & histología , Estudios Prospectivos , Interpretación de Imagen Radiográfica Asistida por Computador , Resultado del TratamientoRESUMEN
This study involved a retrospective evaluation of patients subjected to surgery for dentofacial deformities treated without induced controlled hypotension (group I, n=50) and a prospective evaluation of patients who were subjected to surgery under hypotensive general anaesthesia (group II, n=50). No statistical differences were found between the study groups with regard to the duration of surgery. However, there were statistically significant differences in the need for blood transfusion and the occurrence of bradycardia during the maxillary down-fracture. Hypotensive anaesthesia decreased the need for a blood transfusion and the occurrence of bradycardia, and is therefore considered highly beneficial for patients undergoing orthognathic surgery.
Asunto(s)
Hipotensión Controlada , Procedimientos Quirúrgicos Ortognáticos , Anestesia General , Bradicardia/epidemiología , Transfusión de Eritrocitos/estadística & datos numéricos , Femenino , Humanos , Masculino , Tempo Operativo , Estudios Prospectivos , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Atrophic mandible fractures are frequently a challenge to stabilize. This study evaluated, through mechanical testing in vitro, the number of locking screws that is sufficient to withstand loading when applied with a locking reconstruction plate in the fixation of atrophic mandible fractures. Polyurethane mandibles with a simulated linear fracture at the midline were used as substratum. Results show that resistance of the fixation is poor when one and two screws are used on each side of the fracture. Three screws on each side of the fracture significantly increases the resistance to displacement. However, no additional strength is added to the construct when more than three screws per side are used.
Asunto(s)
Placas Óseas , Tornillos Óseos , Fijación Interna de Fracturas/instrumentación , Técnicas de Fijación de Maxilares/instrumentación , Fracturas Mandibulares/cirugía , Pérdida de Hueso Alveolar/complicaciones , Análisis de Varianza , Fenómenos Biomecánicos , Análisis del Estrés Dental , Humanos , Fracturas Mandibulares/etiología , Estadísticas no ParamétricasRESUMEN
Recent studies have evaluated many methods of internal fixation for sagittal split ramus osteotomy (SSRO), aiming to increase stability of the bone segments while minimizing condylar displacement. The purpose of this study was to evaluate, through biomechanical testing, the stability of the fixation comparing a specially designed bone plate to other two commonly used methods. Thirty hemimandibles were separated into three equal groups. All specimens received SSRO. In Group I the osteotomies were fixed with three 15 mm bicortical positional screws in an inverted-L pattern with an insertion angle of 90°. In Group II, fixation was carried out with a four-hole straight plate and four 6mm monocortical screws. In Group III, fixation was performed with an adjustable sagittal plate and eight 6mm monocortical screws. Hemimandibles were submitted to vertical compressive loads, by a mechanical testing unit. Averages and standard deviations were submitted to analysis of variance using the Tukey test with a 5% level of significance. Bicortical screws presented the greatest values of loading resistance. The adjustable miniplate demonstrated 60% lower resistance compared to bicortical screws. Group II presented on average 40% less resistant to the axial loading.
Asunto(s)
Placas Óseas , Fijación Interna de Fracturas/instrumentación , Técnicas de Fijación de Maxilares/instrumentación , Mandíbula/cirugía , Osteotomía Sagital de Rama Mandibular/métodos , Fenómenos Biomecánicos , Fuerza Compresiva , Análisis del Estrés Dental , Humanos , Modelos Anatómicos , Osteotomía Sagital de Rama Mandibular/instrumentación , PoliuretanosRESUMEN
The authors verified the anatomical location of the mandibular foramen, lingula and antilingula in dry mandibles, aiming to obtain information that could be used when performing mandibular osteotomies. Forty-four mandibles (88 sides) were evaluated. The distances were measured using a sliding calliper, with the mandibles fixed in a reproducible position. Results showed that the mandibular foramen is on average 5.82 mm below the lingula. Regarding the statistical comparison between the mandibular foramen entrance and the antilingula position, there is no correlation between the position of those two structures in the studied sample. The mandibular foramen is slightly posterior in relation to the centre of the ramus. The lingula is an important anatomic landmark for ramus surgery, and for determining the distance to the mandibular foramen entrance. The use of the antilingula as a landmark for the position of the vertical ramus osteotomy is not recommended.
Asunto(s)
Puntos Anatómicos de Referencia/anatomía & histología , Mandíbula/anatomía & histología , Proceso Alveolar/anatomía & histología , Cefalometría/instrumentación , Cefalometría/métodos , Humanos , Nervio Mandibular/anatomía & histología , OsteotomíaRESUMEN
This study compared the fixation of autogenous onlay bone grafts with cyanoacrylate glue (Super Bonder) and with titanium screws. Twenty rabbits underwent bilateral parietal ostectomies. Bone segments were fixed anteriorly to the resulting bone defect. In group I, the grafts were fixed with 4 mm long, 1.5 mm diameter screws; in group II, adhesive was used. The animals were killed after 5, 15, 30, 60 and 120 days. Histomorphometric analysis was used to quantify the maintenance of the graft area. Discrete areas of inflammatory reaction were seen in both groups after 5 days and for group II after 15 days. After 30 days, new bone formation was seen at the interface of the grafts. After 120 days, the graft was incorporated into the host bed in group I and partially incorporated in group II. There was a significant statistical difference regarding the mean graft areas between 15 and 120 days (p<0.001) and between fixation methods (p<0.002). Fixation with adhesive promoted a significantly greater area of bone graft than screw fixation, independent of time period. The adhesive was biocompatible, presented similar stability to the screw and maintained the bone area, although there was a delay in graft incorporation.
Asunto(s)
Cementos para Huesos/uso terapéutico , Tornillos Óseos , Trasplante Óseo/métodos , Cianoacrilatos/uso terapéutico , Oseointegración/fisiología , Hueso Parietal/cirugía , Implantes Absorbibles , Análisis de Varianza , Animales , Trasplante Óseo/instrumentación , Fijación Interna de Fracturas/instrumentación , Fijación Interna de Fracturas/métodos , Estudios Longitudinales , Masculino , Oseointegración/efectos de los fármacos , Conejos , TitanioRESUMEN
The purpose of this study was to compare by qualitative histology the efficacy of rigid internal fixation with titanium system and the Lacto Sorb system in mandibular fractures in rabbits. Thirty male adult rabbits Oryctolagus cuniculus were used. Unilateral mandibular osteotomies were performed between the canine and first premolar. The animals were divided into two groups: for Group I-rigid internal fixation was performed with titanium system 1.5 mm (Synthes, Oberdorf, Switzerland), with two screws of 6 mm (bicortical) on each side of the osteotomy. For Group II-rigid internal fixation was performed with PLLA/PGA system 1.5 mm (Lacto Sorb, WLorenz, Jacksonville, FL, USA). The histological analysis evaluated the presence of inflammatory reaction, degree of bone healing and degree of resorption of the Lacto Sorb screws. The results of both fixation systems were similar, only with a small difference after 15 and 30 days. In Group I a faster bony healing was noted. But after 60 days, bony healing was similar in both groups. It is concluded that both PLLA/PGA and titanium plates and screws provide sufficient strength to permit mandibular bone healing. The resorption process of PLLA/PGA osteosynthesis material did not cause acute or chronic inflammatory reaction or foreign body reaction during the studied period.
Asunto(s)
Implantes Absorbibles , Placas Óseas , Fijación Interna de Fracturas/instrumentación , Fracturas Mandibulares/cirugía , Titanio , Animales , Materiales Biocompatibles/química , Tornillos Óseos , Diseño de Equipo , Células Gigantes/patología , Ácido Láctico/química , Masculino , Fracturas Mandibulares/patología , Osteoblastos/patología , Osteocitos/patología , Osteogénesis/fisiología , Osteotomía , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/química , Conejos , Factores de Tiempo , Titanio/química , Cicatrización de Heridas/fisiologíaRESUMEN
The aim of this study was to determine, through cephalometric analysis, the anterior height of the mandible after vestibuloplasty through the lipswitch technique. Thirteen patients (8 women and 5 men) with ages between 32 and 77 years (mean age of 54.3 years) were evaluated. The postoperative periods were 30, 90 and 180 days. During this time there was a reduction of 0.6 mm in the anterior height of the mandible, which was not significant.
Asunto(s)
Mandíbula/diagnóstico por imagen , Vestibuloplastia/métodos , Adulto , Anciano , Cefalometría , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , RadiografíaRESUMEN
The authors studied the behavior of calcium phosphate materials used as inlay implants into bone cavities prepared in the zygomatic arch of rats. Fifty male albino rats were divided into four groups as follows: group I-preparation of bone cavities which did not receive any implant material as controls; group II-implants of Interpore 200; group III-implants of experimental hydroxylapatite; group IV-implants of experimental hydroxylapatite combined with collagen. The animals were sacrificed after 5, 15, 30, 60 and 120 days and the specimens were submitted to histological analysis. Results showed that the experimental hydroxylapatite used in group III presented better osteogenic properties compared to the other materials. All tested materials were biocompatible, although group IV presented a more intense inflammatory response.
Asunto(s)
Sustitutos de Huesos/uso terapéutico , Colágeno/uso terapéutico , Durapatita/uso terapéutico , Cigoma/cirugía , Animales , Materiales Biocompatibles/uso terapéutico , Tejido Conectivo/patología , Fibroblastos/patología , Estudios de Seguimiento , Células Gigantes/patología , Linfocitos/patología , Macrófagos/patología , Masculino , Neutrófilos/patología , Osteoblastos/patología , Osteogénesis/fisiología , Ratas , Ratas Wistar , Cigoma/patologíaAsunto(s)
Fracturas Orbitales/patología , Equimosis/patología , Edema/patología , Exoftalmia/patología , Estudios de Seguimiento , Fijación Interna de Fracturas , Fracturas Óseas/patología , Fracturas Óseas/cirugía , Seno Frontal/lesiones , Seno Frontal/cirugía , Humanos , Masculino , Persona de Mediana Edad , Fracturas Orbitales/cirugíaRESUMEN
Albright's syndrome is characterized by the presence of polyostotic fibrous dysplasia, endocrinopathies and brown spots on the skin. In the present article the authors describe a case occurring in a 20-year-old female patient, who is currently being followed radiographically after a mandibular bone biopsy.
Asunto(s)
Displasia Fibrosa Poliostótica/patología , Adulto , Asimetría Facial/patología , Femenino , Estudios de Seguimiento , Hueso Frontal/patología , Humanos , Hiperpigmentación/patología , Enfermedades Mandibulares/patologíaRESUMEN
The interference of a blood clot in the first postoperative hours of dental extraction wounds was studied in rats. Sixty male albino rats were divided into two groups: Group I, immediately after extraction of right maxillary incisor the gingival mucosa was approximated and sutured; Group II, after 6 to 8 minutes postoperatively the blood clot was removed with saline irrigation and absorbent paper cones. The mucosa was then approximated and sutured. Six animals in each group were sacrificed after 12 hours, 1, 4, 7 and 10 days. There was a profound delay in healing in Group II since, although a new blood clot was later formed, it was not organized. The quality and the constitution, maintenance and retraction of the clot are the regulating factors in connective tissue formation during alveolar healing.
Asunto(s)
Coagulación Sanguínea/fisiología , Tejido de Granulación/crecimiento & desarrollo , Extracción Dental , Cicatrización de Heridas/fisiología , Proceso Alveolar/fisiología , Animales , Regeneración Ósea , Incisivo , Masculino , Maxilar , Ratas , Ratas WistarAsunto(s)
Encía/fisiología , Poliglactina 910 , Ácido Poliglicólico , Suturas , Cicatrización de Heridas/fisiología , Animales , Encía/efectos de los fármacos , Gingivitis/inducido químicamente , Masculino , Poliglactina 910/efectos adversos , Ácido Poliglicólico/efectos adversos , Ratas , Ratas Wistar , Extracción DentalRESUMEN
A comparative study was made of two methods of cartilage preservation, 98% glycerol and 70% alcohol. Rib cartilage was treated by either of these methods and transplanted into the malar process of rats. Cartilage grafts preserved by both methods were equally well tolerated. Resorption and bone substitution were similar in both groups after 120 days, although resorption was greater for the alcohol-preserved cartilage up until day 30. The possible reduction in antigenicity by the 98% glycerol did not produce any difference of behavior from the cartilage preserved in 70% alcohol.
Asunto(s)
Cartílago/trasplante , Conservación de Tejido/métodos , Animales , Regeneración Ósea/inmunología , Cartílago/efectos de los fármacos , Cartílago/inmunología , Etanol/farmacología , Glicerol/farmacología , Masculino , Ratas , Ratas Wistar , Trasplante HomólogoRESUMEN
Using a questionnaire, 41 patients scheduled for orthognathic surgery were evaluated pre- and postoperatively to determine some of their psychological characteristics and treatment outcome from the patient's standpoint. Among other conclusions, the results showed that some patients may not fully understand the details of their deformity, despite a full explanation by the orthodontist and surgeon. Expectations regarding treatment outcome may be unrealistic even in patients with valid self-motivation for surgery. Social adjustment usually improves after treatment. Functional changes were noticed by over 80% of the patients and esthetic changes in over 90%.
Asunto(s)
Actitud Frente a la Salud , Maloclusión/psicología , Maloclusión/cirugía , Adolescente , Adulto , Estética Dental , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Maloclusión/patología , Maloclusión/fisiopatología , Mandíbula/patología , Mandíbula/fisiopatología , Mandíbula/cirugía , Maxilar/patología , Maxilar/fisiopatología , Maxilar/cirugía , Motivación , Satisfacción del Paciente , Personalidad , Autoimagen , Ajuste SocialRESUMEN
A comparison was made of autogenous grafts of rib cartilage with and without removal of the perichondrium, applied to the malar process of rats. Seventy-two male albino rats were divided into two groups according to the kind of graft received by each animal. The experimental periods were 5, 10, 20, 30, 60 and 120 postoperative days. The results showed that, in the control group, the grafts maintained their vitality for the whole experimental period and the perichondrium was biologically integrated into the host bed. Appositional growth was also observed. The treated animals showed intense resorption of the grafts and more intense bone neoformation. The newly formed bone was in intimate contact with the graft in both groups.
Asunto(s)
Cartílago/patología , Cartílago/trasplante , Cigoma/cirugía , Animales , Coagulación Sanguínea , Tejido Conectivo/patología , Fibroblastos/patología , Supervivencia de Injerto , Linfocitos/patología , Masculino , Neutrófilos/patología , Ratas , Costillas , Factores de TiempoRESUMEN
The present study was designed to histologically evaluate the behavior of free autogenous cartilage grafts to the mandible of rats. A 3-mm segment was removed from the last rib of male adult rats and transplanted fresh to a receptor bed prepared on the mandibular ramus. The results showed that the grafts maintained their vitality up to 120 days and the perichondrium was biologically integrated to the osseous bed. Appositional growth of the grafts was found. New bone formation was observed in close proximity to the grafts, but newly formed trabeculae did not arise from perichondrium.