Buffered 2% articaine in buccal infiltration of mandibular molars: a randomized triple-blind clinical trial.

This crossover study aimed to compare the anesthetic effects of buffered 2% articaine with 1:200,000 epinephrine with that of non-buffered 4% articaine with 1:200,000 epinephrine. Forty-seven volunteers were administered two doses of anesthesia in the buccal region of the second mandibular molars in two sessions using 1.8 mL of different local anesthetic solutions. The onset time and duration of pulp anesthesia, soft tissue pressure pain threshold, and the score of pain on puncture and burning during injection were evaluated. The operator, volunteers, and statistician were blinded. There were no significant differences in the parameters: onset of soft tissue anesthesia (p = 0.80), duration of soft tissue anesthesia (p = 0.10), onset of pulpal anesthesia in the second (p = 0.28) and first molars (p = 0.45), duration of pulp anesthesia of the second (p = 0.60) and first molars (p = 0.30), pain during puncture (p = 0.82) and injection (p = 0.80). No significant adverse events were observed. Buffered 2% articaine with 1:200,000 epinephrine did not differ from non-buffered 4% articaine with 1:200,000 epinephrine considering anesthetic success, safety, onset, duration of anesthesia, and pain on injection.

Buffered 2% articaine in buccal infiltration of mandibular molars: a randomized triple-blind clinical trial

Abstract This crossover study aimed to compare the anesthetic effects of buffered 2% articaine with 1:200,000 epinephrine with that of non-buffered 4% articaine with 1:200,000 epinephrine. Forty-seven volunteers were administered two doses of anesthesia in the buccal region of the second mandibular molars in two sessions using 1.8 mL of different local anesthetic solutions. The onset time and duration of pulp anesthesia, soft tissue pressure pain threshold, and the score of pain on puncture and burning during injection were evaluated. The operator, volunteers, and statistician were blinded. There were no significant differences in the parameters: onset of soft tissue anesthesia (p = 0.80), duration of soft tissue anesthesia (p = 0.10), onset of pulpal anesthesia in the second (p = 0.28) and first molars (p = 0.45), duration of pulp anesthesia of the second (p = 0.60) and first molars (p = 0.30), pain during puncture (p = 0.82) and injection (p = 0.80). No significant adverse events were observed. Buffered 2% articaine with 1:200,000 epinephrine did not differ from non-buffered 4% articaine with 1:200,000 epinephrine considering anesthetic success, safety, onset, duration of anesthesia, and pain on injection.

Influence of Population Size, the Human Development Index and the Gross Domestic Product on Mortality by COVID-19 in the Southeast Region of Brazil.

We evaluated the influence of population size (POP), HDI (Human Development Index) and GDP (gross domestic product) on the COVID-19 pandemic in the Southeast region of Brazil, between February 2020 and May 2021. METHODS: Cases, deaths, incidence coefficient, mortality rate and lethality rate were compared among states. The cities were divided into strata according to POP, GDP, and HDI. Data were compared by Welch's ANOVA, nonlinear polynomial regression, and Spearman's correlation test (rS). RESULTS: The highest incidence coefficient (p < 0.0001) and mortality rate (p < 0.05) were observed in the states of Espírito Santo and Rio de Janeiro, respectively. Until the 45th week, the higher the POP, the higher the mortality rate (p < 0.01), with no differences in the remaining period (p > 0.05). There was a strong positive correlation between POP size and the number of cases (rS = 0.92, p < 0.0001) and deaths (rS = 0.88, p < 0.0001). The incidence coefficient and mortality rate were lower (p < 0.0001) for low GDP cities. Both coefficients were higher in high- and very high HDI cities (p < 0.0001). The lethality rate was higher in the state of Rio de Janeiro (p < 0.0001), in large cities (p < 0.0001), in cities with medium GDP (p < 0.0001), and in those with high HDI (p < 0.05). CONCLUSIONS: Both incidence and mortality were affected by time, with minimal influence of POP, GDP and HDI.

Correlation between facial types and muscle TMD in women: an anthropometric approach.

Temporomandibular disorders (TMD) affecting the articular disc and/or the facial muscles are common among the population, recording a higher incidence in women age 20-40 years. The aim of this study was to investigate the correlation between facial types and muscle TMD in women. This study comprised 56 women age 18 to 49 years, seeking treatment for TMD at the School of Medicine, Federal University of São Paulo. All of the study individuals were diagnosed with muscle TMD, based on the Research Diagnostic Criteria (RDC). Facial type was determined using the Facial Brugsch Index and classified as euryprosopic (short and/or broad), mesoprosopic (average width) and leptoprosopic (long and/or narrow). The data were submitted to the Chi-square test and ANOVA-Tukey's test to conduct the statistical analysis. The faces of 27 individuals were classified as euryprosopic (48%), 18 as mesoprosopic (32%), and 11 as leptoprosopic (20%). A statistically significant difference (Chi-square, p = 0.032) was found among the facial types, in that leptoprosopic facial types showed the lowest values for muscle TMD. A greater number (p = 0.0007) of cases of muscle TMD were observed in the 20 to 39 year-old subjects than in the subjects of other age segments. In conclusion, women with euryprosopic facial types could be more susceptible to muscle TMD. Further studies are needed to investigate this hypothesis.

Correlation between facial types and muscle TMD in women: an anthropometric approach

Temporomandibular disorders (TMD) affecting the articular disc and/or the facial muscles are common among the population, recording a higher incidence in women age 20-40 years. The aim of this study was to investigate the correlation between facial types and muscle TMD in women. This study comprised 56 women age 18 to 49 years, seeking treatment for TMD at the School of Medicine, Federal University of São Paulo. All of the study individuals were diagnosed with muscle TMD, based on the Research Diagnostic Criteria (RDC). Facial type was determined using the Facial Brugsch Index and classified as euryprosopic (short and/or broad), mesoprosopic (average width) and leptoprosopic (long and/or narrow). The data were submitted to the Chi-square test and ANOVA-Tukey’s test to conduct the statistical analysis. The faces of 27 individuals were classified as euryprosopic (48%), 18 as mesoprosopic (32%), and 11 as leptoprosopic (20%). A statistically significant difference (Chi-square, p = 0.032) was found among the facial types, in that leptoprosopic facial types showed the lowest values for muscle TMD. A greater number (p = 0.0007) of cases of muscle TMD were observed in the 20 to 39 year-old subjects than in the subjects of other age segments. In conclusion, women with euryprosopic facial types could be more susceptible to muscle TMD. Further studies are needed to investigate this hypothesis.

Relations between the mandibular canal and I, II and III Angle classes in panoramic radiographs / Relaciones entre el canal mandibular y clases I, II y III de Angle en radiografías panorámicas

To prevent injury to the inferior alveolar nerve during dental procedures, knowledge of its anatomical location and course of the mandibular canal is imperative. The aim of this study was evaluate the location on panoramic radiographs of the mandibular canal in relation to the apices of the permanent mandibular molars and base mandible, and relate the type of mandibular canal with Angle classes I, II and III. We evaluated 748 panoramic radiographs distributed according to sex and occlusal class (Angle I, II and III) of fully dentate individuals, 18­51 age group. The radiographs were divided according to Angle classes based on cephalometric tracing, clinical data from the medical records of each individual and the analysis of of the maxillar and mandibular dental arches models. The same individuals had the mandibular canal bilaterally assessed, and classified according to their location relative to the root apices of the mandibular molars and mandible base. Measurements of the distance from the mandibular canal to the apices of the teeth and mandible base were made on the Software ImageLab2000®. The intra-observer reproducibility of measurements on radiographs was assessed using the coefficient of variation (p<0.0001). Data were submitted to Kruskal-Wallis test, on software BioEstat 5.0. There were statistically significant differences (Kruskal-Wallis test, p <0.0001) between the occlusal classes, with the type of mandibular canal. A larger number of canals types 2 and 3 in class III individuals than in others. In conclusion, the location of the mandibular canal presents morphological changes in relation to the apices of the permanent molars, and the mandibular base according to the Angle classes I, II and III.

Para evitar lesiones del nervio alveolar inferior durante los procedimientos odontológicos, el conocimiento de la localización anatómica y curso del canal mandibular (CM) es imprescindible. El objetivo fue evaluar la localización del CM sobre radiografías panorámicas en relación con los ápices de los molares mandibulares permanentes y la base mandibular, relacionando el tipo de CM con las clases I, II y III de Angle. Se evaluaron 748 radiografías panorámicas distribuidas según sexo y clase oclusal (I, II y III de Angle) en individuos totalmente dentados (edad entre 18-51 años). Las radiografías fueron divididas de acuerdo a las clases de Angle según su trazado cefalométrico, datos clínicos de los registros médicos de cada individuo y el análisis de modelos de sus arcos dentarios mandibulares y maxilares. En los individuos se evaluó el CM bilateralmente y se clasificó de acuerdo a su ubicación en relación con los ápices radiculares de los molares mandibulares y base mandibular. Las mediciones de distancia desde el CM a los ápices radiculares y base mandibular se hicieron con el programa ImageLab2000®. Se evaluó la reproducibilidad intra-observador de las mediciones en las radiografías usando el coeficiente de variación (p<0,0001). Los datos fueron sometidos a la prueba de Kruskal ­Wallis con el programa BioEstat 5.0. Se observaron diferencias estadísticamente significativas (prueba de Kruskal-Wallis, p<0,0001) entre las clases oclusales y el tipo de CM. Hubo mayor número de canales tipos 2 y 3 en los individuos clase III. La ubicación del canal mandibular presenta cambios morfológicos en relación con los ápices de molares permanentes y la base mandibular de acuerdo a las clases I, II y III de Angle.

Altered mandibular growth under functional posterior displacement in rats.

OBJECTIVE: To test the null hypothesis that there is no difference in mandibular growth between growing rats with posterior functional mandibular displacement and growing rats without functional mandibular displacement. MATERIALS AND METHODS: Twenty female Wistar rats (5 weeks old) were randomized into two groups: (1) control and (2) mandible posterior displacement in the occluded condition induced by an occlusal guiding appliance. After 8 weeks all animals were sacrificed, cone beam computed tomography scan images of the heads were taken using the classic I-CAT, and acrylic rapid-prototyped templates of the mandibles were constructed. Mandibular length, ramus height, and intercondylar distance were measured. Mandibular length and ramus height were submitted to the two-way analysis of variance, while intercondylar distance was analyzed by nonpaired Student's t-test. RESULTS: Mandibular length was bigger (P < .0001) in the control than in the experimental group, but no significant difference was found between the left and right sides (P  =  .9380). No significant differences were observed for ramus height and intercondylar distance. CONCLUSIONS: The results of this study demonstrated that functional posterior displacement of the mandible in growing rats resulted in shorter mandibular length.

Effect of different light-curing modes on degree of conversion, staining susceptibility and stain's retention using different beverages in a nanofilled composite resin.

STATEMENT OF PROBLEM: It is unknown whether the staining pigment concentration would affect the color of composite resin and whether the absorption of the staining pigment is related to the degree of conversion (DC). PURPOSE: The purpose of this study was to evaluate the effect of light-curing units (LCUs) on DC, superficial staining (ΔE), and pigment concentration (PC) in a nanofilled composite resin (Z350, 3M ESPE) using different beverages. MATERIALS AND METHODS: Specimens were polymerized for 20 seconds using four LCUs (N=50): quartz-tungsten-halogen (QTH)--450 mW/cm(2); laser (LAS)--300 mW/cm(2); second-generation light-emitting diode (LED)-1100 mW/cm(2); and third generation LED--700 mW/cm(2). DC (%) was measured using Fourier transform infrared spectroscopy. Specimens concerning each group (N=10) were then immersed in one of the solutions (distilled water, red wine, whisky, coffee, and cola--40 min/day, for 40 days). Specimen's color was measured before and after exposure to solutions using a colorimeter (Commission Internacionale de I'Eclairaga L*a*b* color scale), and ΔE was calculated. Specimens were then prepared for the spectrophotometric analysis to measure PC. Data were submitted to two-way analysis of variance and Tukey's test (p=0.05). RESULTS: DC: QTH presented the lowest DC, with statistical differences for LAS, LED 2, and LED 3. Whisky and wine showed lower PC mean values than cola and coffee. No statistical difference was observed for LCUs regarding PC and all staining solutions, except cola. Whisky showed the highest values for ΔE regarding all LCUs. Wine showed statistically lower ΔE than whisky, with water presenting the lowest ΔE. LAS and QTH showed higher values than LED 2 concerning ΔE. CONCLUSION: LCUs interfered with DC and altered the PC and ΔE of the composite resin submitted to different staining solutions. There was no correlation among DC, PC, and ΔE. CLINICAL SIGNIFICANCE: Light-curing modes might interfere with staining susceptibility, stain's retention, and DC of a composite resin, compromising the clinical performance. The highest pigment absorption was not associated with the highest superficial staining of the composite resin. Alcoholic drinks lead to greater superficial staining and non-alcoholic solutions lead to a higher pigment concentration.