Dr. Hugo Ariel Hernández-Parada: Análisis Bibliométrico de su Obra y Legado para la Anatomía Chilena / Dr. Hugo Ariel Hernández-Parada: Bibliometric Analysis of his Work and Legacy for Chilean Anatomy

La presente investigación documental con diseño bibliométrico pretender caracterizar la producción científica del Dr. Hugo Ariel Hernández-Parada, fundador del actual Instituto de Anatomía, Histología y Patología de la Universidad Austral de Chile (UACh). Por medio de la búsqueda electrónica en seis bases de datos se identificaron 42 estudios (41 artículos y 1 tesis), cuyo análisis bibliométrico determinó que su quehacer dentro de la investigación en el campo de la Anatomía Humana estuvo centrado en el estudio del Sistema Nervioso Autónomo, seguida del Sistema Nervioso Periférico, Miología y Anatomía de cabeza y cuello. La mayoría de sus obras fueron realizadas en muestras humanas (fetos), publicadas en idioma español, en revistas chilenas, y como autor principal en 41 de los 42 registros encontrados. Por medio de esta investigación, se pretende recordar y rendir homenaje a este destacado anatomista, cuya obra contribuyó al desarrollo y difusión de la Anatomía Humana en Chile.

SUMMARY: This documentary research via bibliometric design, aims to characterize the scientific contribution of Dr. Hugo Ariel Hernández-Parada, the founder of the current Institute of Anatomy, Histology and Pathology of the Universidad Austral de Chile (UACh). An electronic search was carried out in six databases, 42 studies (41 articles and 1 thesis) were identified. Their bibliometric analysis determined that the work of these research studies in the field of Human Anatomy was focused on the study of the Autonomous Nervous System, followed by the Peripheral Nervous System, Myology and Anatomy of the head and neck. Most of his works were carried out on human samples (fetuses), published in Spanish in Chilean science journals, and as the main author in 41 of the 42 records found. Through this research, it is intended to remember and offer tribute to this outstanding anatomist, whose work contributed to the development and diffusion of human anatomy in Chile.

Enseñanza de la Anatomía Humana en la Universidad Austral de Chile: Pasado, Presente y Futuro / Teaching of Human Anatomy at the Universidad Austral de Chile: Past, Present and Future

La presente revisión narrativa trata de caracterizar como ha sido el proceso de enseñanza de la anatomía en la Universidad Austral de Chile (UACh), presentando una visión histórica desde los inicios de la Universidad a los tiempos actuales y una reflexión sobre el futuro de la Anatomía Humana. Se describen los orígenes del Instituto de Anatomía de la UACh, primeros académicos, logros institucionales, convenios interinstitucionales; además, se detallan los métodos y estrategias educativas utilizadas en la actualidad para la enseñanza anatómica y se presenta una visión panorámica del porvenir como instituto de docencia e investigación en el campo de la Anatomía humana.

SUMMARY: This narrative review tries to characterize how the anatomy teaching process has been carried out at the Universidad Austral de Chile (UACh), presenting a historical vision from the beginnings of the University to the present time and a reflection on the future of Human Anatomy. The origins of the Human Anatomy Institute at the UACh, first academics, institutional achievements, inter-institutional agreements are described; in addition, the educational methods and strategies currently used for anatomical teaching are detailed and a panoramic vision of the future as a teaching and research institute in the field of human anatomy is presented.

Effect of upper lip compression on pain reduction during local anesthesia. A split-mouth randomized clinical trial

Objectives: To evaluate the effect of pressure on the skin of upper lip in decreasing pain perception during a local maxillary anesthetic injection. Material and Methods: A split-mouth crossover randomized clinical trial was designed. Seventy-one volunteer students (23.6±1.9 years old, 53.5% women) were selected. A group chosen at random had their left or right side of upper lip compressed by a wooden clothes peg as the compression instrument and 0.6 ml of lidocaine 2% with epinephrine 1:100,000 was administered at the buccal apex level of the lateral incisors tooth. Two weeks later anesthesia was administered on the opposite side of the lip according to the randomization recorded. The intensity of perceived pain level between the two injections using a 100 mm visual analog scale (VAS) and co-variable effect were compared (Wilcoxon test p < 0.05, RStudio). Results: The average of the perceived pain with and without upper lip compression was 27.6±14.5 mm (range 0-80 mm) and 36.33±17.9 mm (range 10-90 mm) respectively (p= 0.002). No significant differences were recorded according the covariance analysis with the sex (p = 0.55) and age (p = 0.89). Conclusion: The upper lip compression significantly reduces the perception of pain during a local maxillary anesthetic technique.

Position of digitally guided implants in completely edentulous maxillae by using a modified double-scan and overlap of three digital surface protocol.

STATEMENT OF PROBLEM: In patients with a completely edentulous maxilla, the variability in resilience and mucosal thickness and the lack of teeth and rigid supporting structures may lead to poor adaptation of the surgical guide and significant variation in the definitive implant position. Whether a modified double-scan technique with overlap of surfaces will improve implant placement is unclear. PURPOSE: The purpose of this prospective clinical study was to evaluate the 3-dimensional position and the correlation of 6 dental implants in participants with a completely edentulous maxilla using a mucosa-supported flapless surgical guide designed with 3 matched digital surfaces obtained with a modified double-scan protocol. MATERIAL AND METHODS: Dental implants were installed with an all-on-6 protocol in the edentulous maxilla of participants at the Santa Cruz Public Hospital, Chile. A stereolithographic mucosa-supported template was fabricated from a cone beam computed tomography (CBCT) scan made with a prosthesis with 8 radiopaque ceramic spheres inserted and by scanning the same prosthesis with an intraoral scanner. The mucosa was obtained by digitally casting the relining of the removable complete denture in the design software program. After 4 months, a second CBCT scan was obtained to evaluate the position of the installed implants measured at 3 locations: apical, coronal, platform depth, and angulation. Differences in position between the 6 implants in the completely edentulous maxilla and their linear correlation at the measured points were compared with the Kruskal-Wallis and Spearman correlation tests (α=.05). RESULTS: Sixty implants were installed in 10 participants (age 54.3 ±8.2 years; 7 women). The average deviation in the apical axis was 1.02 ±0.9 mm, coronal 0.76 ±0.74 mm, platform depth 0.92 ±0.8 mm, and the major axis angulation of the 6 implants was 2.92 ±3.65 degrees. The implant in the maxillary left lateral incisor region had the most significant deviation in apical and angular points (P<.05). A linear correlation between apical-to-coronal deviations and apical-to-angular deviations was observed for all implants (P<.05). CONCLUSIONS: A stereolithographic mucosa-supported guide designed with the overlap of 3 digital surfaces had average dental implant position values similar to those reported by systematic reviews and meta-analyses. In addition, implant position varied based on the location of the implant installation in the edentulous maxilla.

Endodoncia guiada estática, una opción para obliteración del canal pulpar: serie de casos / Static guided endodontics, an option for pulpal canal obliteration: a case series

En la práctica endodóntica, la etapa del acceso al canal radicular es fundamental para el éxito de las siguientes etapas del tratamiento. En casos de canales pulpares obliterados o calcificados (PCO), lograr encontrar la entrada a estos es un reto en la endodoncia convencional dado el alto riesgo de sufrir un accidente intraoperatorio. Actualmente, existen los tratamientos de endodoncia guiada o accesos guiados digitalmente, una alternativa innovadora y con múltiples beneficios para el abordaje de este tipo de dientes. El objetivo de este reporte de casos fue describir el protocolo de cuatro casos de accesos guiados estáticos para endodoncia en canales obliterados, indicando las ventajas y consideraciones del tratamiento. Se presenta un reporte de casos de cuatro pacientes atendidos entre julio 2021 y junio 2022, que requerían tratamientos endodónticos en dientes anteriores con canales pulpares obliterados. Para la realización de estos procedimientos se requirió una Tomografía Computarizada de Haz Cónico (CBCT) y el escaneo intraoral de la zona a tratar, para poder a través de la ayuda de un software, planificar virtualmente la dirección y longitud de acceso al conducto radicular. Posteriormente, se realizó la impresión en 3D de la guía estática, la cual dirige la entrada de la fresa que se utiliza para encontrar el acceso al canal radicular. En los cuatro casos clínicos en que se realizó la planificación virtual e impresión de la guía de acceso, fue posible encontrar el canal radicular en una sesión, pudiendo realizar el tratamiento endodóntico de manera exitosa y conservadora. En conclusión, la endodoncia guiada estática permite realizar los tratamientos endodónticos en PCO de manera segura, a pesar de la alta complejidad que presentaban.

SUMMARY: In endodontics, the access to the root canal is essential for the treatment success. Pulp canal obliteration (PCO) is a challenge for conventional endodontic treatments with a high risk of fracture of endodontic instruments.Currently, guided endodontic treatments, or digitally guided accesses, are novel alternatives with multiple benefits for the treatment of PCO. The objective of this case report is to describe the protocol for static guided access in PCO, indicating the advantages and considerations of the treatment. A case report of four patients treated between July 2021 and June 2022 is presented. These patients required endodontic treatments in anterior teeth with PCO. In order to virtually plan the direction and length of the access, using a software, we used a cone Beam Computed Tomography (CBCT) and an intraoral scan. Then, a 3D printing of the static guide was made, which directs the entry of the drill. With this method, it was possible to find the root canal in one session and perform the endodontic treatment successfully and conservatively. In conclusion, although static guided endodontics requires planification, it allows a safe endodontic treatment in patients with PCO.

Chilean Patients' Perception of Their Oral Health-Related Quality of Life After Bichectomy.

Objective: To describe the quality of life associated with oral health in patients who have had bichectomy surgery in Chile using the Spanish version of the health-Related Quality of Life instrument (HRQOL-sp). Material and Methods: We designed a cross-sectional study. The HRQOL-sp scale was administered to dental patients in a private clinic who had bichectomy surgery between December 2020 and June 2021. The HRQOL-sp instrument has four domains: oral function, general activity, postoperative signs, symptoms or complications, and pain level. The instrument was administered by telephone survey on days 1, 3, 5 and 7 post-surgery. Interference in quality of life was defined as when patients selected the options "quite a few problems" or "many problems" for oral function and general activity. Signs and symptoms related to post-surgical complications and pain were also described with a verbal rating scale from one to ten. All results were compared between postoperative days according to the domains of the HRQOL-sp scale. Results: Seventy-three patients (age 27.75 ± 8.06 years; 93.15% female) participated. Bichectomy patients report the highest interference in quality of life on the first postoperative day because most were unable to chew (71.23%). On the first and third postoperative days, the most frequent complication was swelling (97.26%), and on the fifth day was ecchymosis (42.47%). The average worst perceived pain was 3.34±2.32 on the verbal analogue scale. The rest of the evaluated items significantly decreased towards the seventh postoperative day (p<0.05). Conclusion: Interference in quality of life associated with bichectomy surgery is greatest on the first postoperative day. Complications and pain levels decreased significantly over time.

Chemotherapy as a risk factor for caries and gingivitis in children with acute lymphoblastic leukemia: A retrospective cohort study.

BACKGROUND: Dental and oral anomalies are among the most common long-term side effects of childhood cancer therapy. AIM: To evaluate chemotherapy as a risk factor for caries lesions and gingivitis in children with acute lymphoblastic leukemia (ALL) treated with the ALL IC-BFM 2009 chemotherapy protocol. DESIGN: A retrospective cohort study was designed. Clinical records of 23 paediatric patients with ALL exposed to chemotherapy in the Regional Hospital in Valdivia, Chile, and 46 unexposed patients assessed every 3 months for 24 months were analyzed. The data on gender, age, index of the number of decayed, missing, or filled teeth, and the presence of gingivitis were recorded (Mann-Whitney U test and logistic regression analysis, p ≤ .05). RESULTS: A significantly greater frequency of gingivitis (69.57%; p < .002) and a mean of new caries lesions were observed in children treated with chemotherapy than in the unexposed children (p < .01). The chemotherapy protocol presented a relative risk of 2.15 (95% CI = 1.22 - 2.66; p = .01) for new caries lesions and 2.29 (95% CI = 1.76 - 3.82; p = .002) for gingivitis. CONCLUSION: The ALL IC-BFM 2009 chemotherapy protocol in patients with ALL is a risk factor for new caries lesions and gingivitis.

Effect of music at 432 Hz and 440 Hz on dental anxiety and salivary cortisol levels in patients undergoing tooth extraction: a randomized clinical trial.

Objective The aim of this study was to compare the effects of music at 432 Hz, 440 Hz, and no music on the clinical perception of anxiety and salivary cortisol levels in patients undergoing tooth extraction. Methodology A parallel-group randomized clinical trial was conducted. Forty-two patients (average age: 23.8±7.8 years, 27 women) with a moderate level of anxiety were distributed in three groups: use of music for 15 minutes at a frequency of 432 Hz (n=15), at 440 Hz (n=15) and a control group without music (n=12). The CORAH Dental Anxiety Scale and salivary cortisol levels, estimated by the solid phase enzyme-linked immunosorbent assay (ELISA), were measured and compared before and after the music intervention between groups (two-way ANOVA-Tukey p<0.05, RStudio). Results Significantly lower anxiety level values were observed at 432 Hz (8.7±2.67) and 440 Hz (8.4±2.84) compared to the control group (17.2±4.60; p<0.05). The salivary cortisol level at 432 Hz (0.49±0.37 µg/dL) was significantly lower than 440 Hz (1.35±0.69 µg/dL) and the control group (1.59±0.7 µg/dL; p<0.05). Conclusion The use of music significantly decreased clinical anxiety levels, and the frequency of 432 Hz was effective in decreasing salivary cortisol levels before tooth extraction.

Effect of music at 432 Hz and 440 Hz on dental anxiety and salivary cortisol levels in patients undergoing tooth extraction: a randomized clinical trial

Abstract Objective The aim of this study was to compare the effects of music at 432 Hz, 440 Hz, and no music on the clinical perception of anxiety and salivary cortisol levels in patients undergoing tooth extraction. Methodology A parallel-group randomized clinical trial was conducted. Forty-two patients (average age: 23.8±7.8 years, 27 women) with a moderate level of anxiety were distributed in three groups: use of music for 15 minutes at a frequency of 432 Hz (n=15), at 440 Hz (n=15) and a control group without music (n=12). The CORAH Dental Anxiety Scale and salivary cortisol levels, estimated by the solid phase enzyme-linked immunosorbent assay (ELISA), were measured and compared before and after the music intervention between groups (two-way ANOVA-Tukey p<0.05, RStudio). Results Significantly lower anxiety level values were observed at 432 Hz (8.7±2.67) and 440 Hz (8.4±2.84) compared to the control group (17.2±4.60; p<0.05). The salivary cortisol level at 432 Hz (0.49±0.37 μg/dL) was significantly lower than 440 Hz (1.35±0.69 μg/dL) and the control group (1.59±0.7 μg/dL; p<0.05). Conclusion The use of music significantly decreased clinical anxiety levels, and the frequency of 432 Hz was effective in decreasing salivary cortisol levels before tooth extraction.

Recorrido por la realidad de los laboratorios de anatomía humana de 12 universidades chilenas / Journey through the reality of human anatomy laboratories of 12 Chilean universities

RESUMEN: La enseñanza de la anatomía humana ha estado ligada históricamente al estudio de cadáveres humanos mediante la observación y la disección. A pesar del paso de los años y los avances en los textos e instrumentos multimediales, no se concibe su educación, sin incorporar los procesos de enseñanza-aprendizaje que se llevan a cabo en los laboratorios de anatomía. El propósito de esta investigación fue describir los recursos físicos, educativos, humanos y los métodos de fijación y conservación de las muestras cadavéricas de 12 universidades chilenas. Se desarrolló un estudio descriptivo donde se visitaron 12 laboratorios de anatomía humana, de los cuales 10 fueron remodelados posterior al año 2000. La capacidad máxima que presentaron fue de 103 estudiantes en promedio. Todos refirieron emplear algún tipo de material cadavérico, pero sólo 3 dijeron poseer un stock que les permite realizar prácticos íntegramente con estos elementos. Para la fijación y conservación el 75 % utiliza una fórmula con bajo porcentaje de formaldehído y otro 17 % lo utiliza a gran concentración. El promedio de los docentes que participan en los laboratorios fue de 11,7 por universidad, de los cuales sólo un 14,2 % presentan postítulo o postgrado en la especialidad. Se aprecia una escasa homogeneidad en la implementación de recurso humano, material cadavérico y métodos de conservación libre de formalina entre los laboratorios de anatomía humana de las universidades chilenas. Se requiere intercambiar experiencias, estandarizar y reconocer las mejores prácticas.

SUMMARY: The teaching of human anatomy has historically been linked to the study of human corpses through observation and dissection. Despite the advances in multimedia texts and instruments over the years, anatomy education is not understood without incorporating the teaching-learning processes in the anatomy laboratories. The purpose of thisresearch was to describe the physical, educational, human resources and methods of fixation and conservation of cadaveric samples from 12 Chilean universities. A descriptive study was carried out where 12 human anatomy laboratories were visited, of which 10 were remodeled after the year 2000. The maximum capacity average of the laboratories was 103 students. All those interviewed reported using some type of cadaveric material, but only 3 of the labs have sufficient stock to allow these elements to be used in real practice. For fixation and preservation, 75 % of labs use a low percentage formaldehyde, while 17 % use a high concentration. The average of teachers that participate in the laboratories was of 11.7 per university, of which only 14.2 % present graduate or postgraduate degree in the specialty. Homogeneity is scarce in Chilean universities in reference to the implementation of human resources, cadaveric samples and formalin-free conservation methods in human anatomy laboratories. Therefore, it is important to exchange experiences, standardize and recognize the best practices in this field.

Effect of warming anesthetic on pain perception during dental injection: a split-mouth randomized clinical trial.

BACKGROUND: The purpose of this study is to determine the effectiveness of warming anesthesia on the control of the pain produced during the administration of dental anesthesia injection and to analyze the role of Transient Receptor Potential Vanilloid-1 nociceptor channels in this effect. PATIENTS AND METHODS: A double-blind, split-mouth randomized clinical trial was designed. Seventy-two volunteer students (22.1±2.45 years old; 51 men) from the School of Dentistry at the Universidad Austral de Chile (Valdivia, Chile) participated. They were each administered 0.9 mL of lidocaine HCl 2% with epinephrine 1:100,000 (Alphacaine®) using two injections in the buccal vestibule at the level of the upper lateral incisor teeth. Anesthesia was administered in a hemiarch at 42°C (107.6°F) and after 1 week, anesthesia was administered by randomized sequence on the contralateral side at room temperature (21°C-69.8°F) at a standardized speed. The intensity of pain perceived during the injection was compared using a 100 mm visual analog scale (VAS; Wilcoxon test p<0.05). RESULTS: The use of anesthesia at room temperature produced an average VAS for pain of 35.3±16.71 mm and anesthesia at 42°C produced VAS for pain of 15±14.67 mm (p<0.001). CONCLUSION: The use of anesthesia at 42°C significantly reduced the pain during the injection of anesthesia compared to its use at room temperature during maxillary injections. The physiological mechanism of the temperature on pain reduction could be due to a synergic action on the permeabilization of the Transient Receptor Potential Vanilloid-1 channels, allowing the passage of anesthetic inside the nociceptors.

Reliability and validity of measuring scale for postoperative complications in third molar surgery.

BACKGROUND: Third molar removal surgery is the most frequently performed surgery in the oral and maxillofacial field with a wide range of items in the quantification of postoperative complications. For their measure, in 2014 a previous scale design was presented. The aim of this study was to determine the reliability and validity of a scale designed to measure and quantify postoperative complications in third molar surgery (TMS). METHODS: A cross-sectional study of a measurement model was designed. Sixty-two patients (mean age 20.5 ± 6.6 years; 36 women) underwent TMS in three Chilean hospitals. In the postoperative check-up on the 7th day, a maxillofacial surgeon and a surgical resident performed independent postoperative assessments, applying the scale. A confirmatory factor analysis was conducted to obtain validity, internal consistency, interobserver reliability and a score to categorize the severity of complications using structural equation model analysis. RESULTS: Nine patients (14.5%) had complications. The scale was defined by two components: "Secondary complication" and "Infection" (Cronbach's alpha 0.71; Interobserver reliability 87.7%) and three categories of postoperative complication: "without or mild", "moderate" and "severe". CONCLUSION: This study presents a reliability and validity scale called "Surgical complication assessment scale in TMS".

[The impact of the orthopedic surgeons' attire on patient preferences]. / ¿La imagen importa? Influencia de la vestimenta del traumatólogo en la elección y confianza del paciente.

BACKGROUND: The formal appearance of health care professionals may influence their trustworthiness. AIM: To determine the effect of the orthopedic surgeon's attire on patients' perceptions of credibility and reliability of professionals. MATERIAL AND METHODS: In a cross-sectional design, 351 patients (mean age 43 ± 17 years, 62% males) from the Department of Orthopedics and Traumatology of a Chilean regional hospital in southem of Chile were chosen to complete a questionnaire of attire preferences, in which five photographs with male and female orthopedic surgeons appeared (executive, formal attire, informal attire, scrubs and casual clothing). The influence of attire in the perception of physicians' trustworthiness to resolve medical situations was analyzed. RESULTS: Forty four percent of patients had no physician gender predilection (p = 0.32). Forty three percent of male and 38% of female patients preferred the use of formal attire. In situations of credibility or confidence, all patients chose mostly the use of white coats with formal attire by professionals. The probability of choosing an orthopedic surgeon with a formal attire was significantly higher among patients who considered the attire and appearance of the professional to be very important (Odds ratio = 3.74; p < 0.01). CONCLUSIONS: Patients prefer orthopedic surgeons wearing white coats and formal attire, which improves credibility of these professionals to correctly solve medical situations.

Relationship between width and length ratios of upper anterior teeth in young chilean population

INTRODUCTION: Knowledge about the size and proportion of upper anterior teeth allows dental rehabilitation taking into consideration the local parameters of a population. The aim of this research is to determine the width, length and the relationship between width and length of central incisor, lateral incisor and canine teeth in both sexes in young Chilean population. METHODOLOGY: A cross-sectional study was performed. Study subjects included 187 dentistry students from two Chilean cities (mean age 21.35+/-2.7 years, 52.9 percent men). The teeth width and height were measured and the width/height ratio was calculated. Differences in measurements according to sex was analyzed (p<0.05; STATA v.10.0). RESULTS: The width and height of the teeth were statistically and proportionally larger in men (p<0.05). The width/height ratio of lateral and canine incisors was significantly higher in women (p<0.05). CONCLUSION: In a sample of young Chileans, upper anterior teeth were longer and wider in men. However, the width/height ratio of teeth was found to be significantly higher in women

¿La imagen importa? Influencia de la vestimenta del traumatólogo en la elección y confianza del paciente / The impact of the orthopedic surgeons' attire on patient preferences

Background: The formal appearance of health care professionals may influence their trustworthiness. Aim: To determine the effect of the orthopedic surgeon's attire on patients' perceptions of credibility and reliability of professionals. Material and Methods: In a cross-sectional design, 351 patients (mean age 43 ± 17 years, 62% males) from the Department of Orthopedics and Traumatology of a Chilean regional hospital in southem of Chile were chosen to complete a questionnaire of attire preferences, in which five photographs with male and female orthopedic surgeons appeared (executive, formal attire, informal attire, scrubs and casual clothing). The influence of attire in the perception of physicians' trustworthiness to resolve medical situations was analyzed. Results: Forty four percent of patients had no physician gender predilection (p = 0.32). Forty three percent of male and 38% of female patients preferred the use of formal attire. In situations of credibility or confidence, all patients chose mostly the use of white coats with formal attire by professionals. The probability of choosing an orthopedic surgeon with a formal attire was significantly higher among patients who considered the attire and appearance of the professional to be very important (Odds ratio = 3.74; p < 0.01). Conclusions: Patients prefer orthopedic surgeons wearing white coats and formal attire, which improves credibility of these professionals to correctly solve medical situations.

Relación entre distancia intercantal y ancho de dientes anterosuperiores en jóvenes chilenos / Relationship between intercanthal distance and width of maxillary anterior teeth in young chilean population

RESUMEN: Objetivo: La distancia intercantal (DIC) es utilizado para la selección de los dientes anterosuperiores y es la dimensión más estable en el tiempo Sin embargo, es variable entre razas y poblaciones, particularmente en Sudamérica. El objetivo de este estudio es establecer la correlación entre DIC y el ancho de los dientes maxilares anteriores en una población adulta jóven del sur de Chile. Materiales y métodos: Estudio de corte transversal. Participaron 111 estudiantes voluntarios (promedio edad 22.4 años; 65.7% hombres) de la ciudad de Valdivia, sur de Chile. Se midió DIC y el ancho mesiodistal del incisivo central superior, la distancia lineal de los cuatro incisivos superiores y de los seis dientes anterosuperiores en modelos de estudio. Se analizó la diferencia de las mediciones según sexo (test de Student; p<0.05) y la correlación lineal entre DIC y las medidas dentales (r=0.8; p<0.05. STATA v.10.0) Resultados: Todas las mediciones fueron significativamente mayores en hombres que en mujeres (p<0.05). Se observó una correlación estadísticamente significativa entre la DIC y la distancia lineal de los cuatro incisivos superiores (p=0.04) y de los seis dientes anterosuperiores (p=0.03). Se obtuvo una razón de 1:0.94 y 1:1.28 de DIC con la distancia lineal de los cuatro incisivos superiores y los seis dientes anterosuperiores, respectivamente. Conclusión: La DIC presentó una correlación lineal y proporcional con los dientes anteriores, pudiendo estimar el ancho lineal de los dientes anterosuperiores en una población adulta joven del Sur de Chile.

ABSTRACT: Objective: Intercanthal distance (ICD) is a parameter used to select the upper anterior teeth and the most stable measurement overtime. However, it is variable between race and populations, particularly in South America. The aim of this study was to establish the correlation between ICD and the width of maxillary anterior teeth in young adult population from southern of Chile. Materials and Methods: A Cross-sectional study was designed. One Hundred eleven volunteers students (average age 22.4 years; 65.7% men) from Valdivia city (southern of Chile) were included. ICD and mesiodistal width of maxillary central incisor, linear distance of the four upper incisors and linear distance of the six upper front teeth in plaster study models weremeasured. The mean of difference measurement between sex (ttest; p<0.05) and the linear correlation between DIC and the width of the upper anterior were analyzed (r=0.8; p<0.05; STATA v.10.0). Results: All measurement were significantly higher in male than female (p<0.05). A statistically significant correlation between ICD and distance of the four upper incisors (p=0.04) and the six upper front teeth (p=0.03) were observed. A 1:0.94 and 1:1.28 ratios between ICD with the linear distance of the upper incisors and the six maxillary anterior were obtained respectively. Conclusion: ICD presented a linear and proportional correlation with maxillary anterior teeth. With these results it is possible to estimate the linear width of the upper front teeth in young adult population from southern of Chile.

Use of Electronic Versus Print Textbooks by Chilean Dental Students: A National Survey.

Electronic textbooks have become available in recent decades as replacements or alternatives for print versions. The aim of this descriptive cross-sectional study was to evaluate the use of electronic versus print textbooks by Chilean dental students. The target population was students from 14 Chilean dental schools. The questionnaire was adapted and translated to Spanish from a previous survey used in a similar study. It consisted of the following variables: preferred type, type used, frequency of use, source, electronic devices used to read, and disposal after use. The use of textbooks was analyzed and compared by gender and course (p≤0.05). The final sample consisted of 3,256 students (21.38±2.5 years of age, 50.8% women). Most of the participants reported using both types of texts, with most (63.9%) preferring print over electronic texts, including significantly more women (p<0.001) and first-year students (p<0.001). Most of the participants (82.8%), more women (p<0.001), and with variations over years of study (p<0.001) reported that they printed out their electronic texts, and 91.8% kept their printed material. Most of the students used electronic books on a daily basis (47.3%) or at least twice a week (30.7%). The main source of electronic textbooks was the Internet (43.8%). A personal computer was the most widely used device for reading electronic texts (95.0%), followed by a cell phone (46.4%) and a tablet (24.5%). Overall, these Chilean dental students preferred print over electronic textbooks, despite having available electronic devices.