Arcelia Meléndez Ocampo

Prevalencia de las maloclusiones asociada con hábitos bucales nocivos en una muestra de mexicanos

Malocclusions are considered by the WHO as the third event by its prevalence and they represent a public health problem. Genetic and environmental risk factors such as abnormal oral habits are of vital importance to consider its frequency, duration and intensity in order to avoid creating specifi c changes in the occlusion. Objective: To determine the prevalence of malocclusions and its association with risk factors, such as pernicious oral habits in a 2 to 15-year- old child population who requested dental care in the Venustiano Carranza peripheral clinic of the UNAM. Method: A cross-sectional study was conducted in 147 children. Previously, the examiners who participated in the study were calibrated with a 98% concordance for pernicious habits and 92% for malocclusions. The epidemiologic information was recollected in one phase that comprised two stages to identify the presence of pernicious oral habits and diagnose the type of malocclusion. The statistical package SPSS 15 was used. Results: The prevalence of pernicious oral habits was 96.6%. The largest number of cases presented at age 4 and in the 6 to 11 years of age during the mixed dentition. Malocclusions were present in both genders with no significant difference. The habit with the highest prevalence was lingual interposition (66.2%); the second was lip suction (49.3%); the third was onychophagia (41.9%) and fi nally, mouth-breathing (31.8%). In regard to malocclusions, the most prevalent was open bite (35.1%) followed by lower anterior crowding (26.4%), upper anterior crowding (19.6%) and lastly, posterior crossbite (12.8%). There was an association between tongue thrusting and open bite (p < 0.000), and with mouth breathing-posterior crossbite (p < 0.012) and Angle class II (p < 0.008). Conclusions: Child population presents greater susceptibility to develop malocclusions during growth so preventive measures should be adopted during this stage.

Comparative analysis between dental, skeletal and chronological age

The purpose of this study was to determine if skeletal age, dental age and chronological age agreed in 41 subjects. The orthodontist not only needs to know the patient’s chronological age, but also he must know what percentage of growth can be expected in one or two years treatment time. This information is obtained by assessing the skeletal age with hand-wrist radiographs, but there are other aids of diagnosis such as the panoramic X-ray on which dental age can be assessed, so that the clinician has two aids for a more comprehensive diagnosis. Unfortunately although these methods are widely commented in Literature in the clinical practice they are not considered that much. In order to evaluate the skeletal age, we used Fishman’s method in the hand-wrist radiograph and to assess dental age, Dermirjian’s method in the panoramic X-ray was used. t test was used to determine the significant differences between the variables and it was applied to a test of analysis of variance (ANOVA). The results suggest exist statistically significant differences between the skeletal age and the dental age, between the dental age and the chronological age, as well as between the skeletal age and the chronological age. In correlation terms it is only observed very little correlation between the chronological age and the dental age. Key words: Dental age, skeletal age, chronological age, biological maturity.

Análisis comparativo entre la edad ósea, edad dental y edad cronológica

El proposito de este estudio fue determinar si coincide la edad osea, la edad dental y la edad cronologica en 41 sujetos. El ortodoncista no solo necesita conocer la edad cronologica del paciente, tambien debe saber que porcentaje de crecimiento puede esperar en uno o dos anos que sera el tiempo de tratamiento, este dato se obtiene valorando la edad osea mediante la radiografia digitopalmar; asi mismo, existen otros auxiliares de diagnostico como la ortopantomografia, a traves de la cual se valora la edad dental, de tal forma que el clinico cuenta con dos auxiliares que complementan el diagnostico. Desafortunadamente aunque estos metodos son ampliamente comentados en la literatura, en la practica no se toman en cuenta. Para evaluar la edad osea se utilizo el metodo de Fishman en la radiografia digitopalmar y para valorar la edad dental se utilizo el metodo de Dermirjian en la ortopantomografia. Se utilizo la prueba t para determinar las diferencias signifi cativas entre las variables y se aplico una prueba de analisis de varianza (ANOVA). Los resultados sugieren que existen diferencias estadisticamente signifi cativas entre la edad osea y la edad dental, entre la edad dental y la edad cronologica, asi como entre la edad osea y la edad cronologica. En terminos de correlacion solo se observa muy poca correlacion entre la edad cronologica y la edad dental. Palabras clave: Edad dental, edad osea, edad cronologica, madurez biologica.

Comparative study between digital and manual cephalometry with digital radiographs

Objective: The objective of this study was to compare the reliability of the measures of the computerized cephalometric program Nemoceph Nx, with the tracing done manually with digital lateral skull radiographs to 91% printed on photographic paper. Methods: We used 20 digital lateral radiographs of the skull taken from 20 patients with a Sirona brand direct digital ORTHOPHOS XG Plus cephalostat. Once the captured image was transferred directly to the same computer program (Nemoceph Nx) it was also printed for the tracing of 12 measures: 6 linear a nd 6 angular. Results: A comparison between the manual tracing and the program Nemoceph Nx measures was performed and we found no statistically signifi cant differences (p > 0.05) between the two groups. Conclusions: The results show an excellent reliability for everyday use of the NX Nemoceph program for diagnosis using cephalometric digital radiography. Key words: Cephalometric software, digital radiography, digital cephalometry.

Post‐evaluation of the neurophaties treatment post‐trauma with therapeutic laser. Model in sciatic nerve of frog

The purpose of this study was to evaluate the compound nerve action potential amplitude and latency measured to determine the degree of myelination and the number of fibers stimulated in a model of stimulated frog sciatic nerve laser at 810 nm as perioperative treatment after injury. It used 30 bullfrogs (Rana catesbeiana) to obtain 60 sciatic nerves forming four groups, groups 1 and 2 worked with nerves in vitro, were dissected in humid chambers for placing isolated organ, was recorded on compound nerve action potential, the second group laser was applied at 24, 48, 72, 96 and 120 hours and at the same time were placed in 10% formalin. Groups 3 and 4 are worked in vivo localizing the nerve and causing damage through compression, occurred over the compound nerve action potential to assess the degree of myelination and the number of fibers stimulated, the group 4 was applied to 810 nm laser (500 Hz, 10 J, 200 mW) after injury, after 48 hours, three frogs were sacrificed by introducing the nerves in 10% for...

Estudio comparativo entre la cefalometría digital y manual con radiografías digitales

Objective: The objective of this study was to compare the reliability of the measures of the computerized cephalometric program Nemoceph Nx, with the tracing done manually with digital lateral skull radiographs to 91% printed on photographic paper. Methods: We used 20 digital lateral radiographs of the skull taken from 20 patients with a Sirona brand direct digital ORTHOPHOS XG Plus cephalostat. Once the captured image was transferred directly to the same computer program (Nemoceph Nx) it was also printed for the tracing of 12 measures: 6 linear a nd 6 angular. Results: A comparison between the manual tracing and the program Nemoceph Nx measures was performed and we found no statistically signifi cant differences (p > 0.05) between the two groups. Conclusions: The results show an excellent reliability for everyday use of the NX Nemoceph program for diagnosis using cephalometric digital radiography.

Prevalence of malocclusions associated with pernicious oral habits in a Mexican sample

Malocclusions are considered by the WHO as the third event by its prevalence and they represent a public health problem. Genetic and environmental risk factors such as abnormal oral habits are of vital importance to consider its frequency, duration and intensity in order to avoid creating specifi c changes in the occlusion. Objective: To determine the prevalence of malocclusions and its association with risk factors, such as pernicious oral habits in a 2 to 15-yearold child population who requested dental care in the Venustiano Carranza peripheral clinic of the UNAM. Method: A cross-sectional study was conducted in 147 children. Previously, the examiners who participated in the study were calibrated with a 98% concordance for pernicious habits and 92% for malocclusions. The epidemiologic information was recollected in one phase that comprised two stages to identify the presence of pernicious oral habits and diagnose the type of malocclusion. The statistical package SPSS 15 was used. Results: The prevalence of pernicious oral habits was 96.6%. The largest number of cases presented at age 4 and in the 6 to 11 years of age during the mixed dentition. Malocclusions were present in both genders with no significant difference. The habit with the highest prevalence was lingual interposition (66.2%); the second was lip suction (49.3%); the third was onychophagia (41.9%) and fi nally, mouth-breathing (31.8%). In regard to malocclusions, the most prevalent was open bite (35.1%) followed by lower anterior crowding (26.4%), upper anterior crowding (19.6%) and lastly, posterior crossbite (12.8%). There was an association between tongue thrusting and open bite (p < 0.000), and with mouth breathing-posterior crossbite (p < 0.012) and Angle class II (p < 0.008). Conclusions: Child population presents greater susceptibility to develop malocclusions during growth so preventive measures should be adopted during this stage. Key words: Pernicious habits, malocclusions, mixed dentition.