Ana Cláudia Rossi

Incidence of Retromolar Foramen in Human Mandibles: Ethnic and Clinical Aspects

SUMMARY: The retromolar foramen allows the passage of the neurovascular bundles that contribute to nutrition and innervation of the pulp and periodontium of the lower teeth. Knowledge of this anatomical variation may prevent complications in the anesthesia and surgical procedures in this area and serve as an anatomical landmark for ethnic identification. The aim of this study was to evaluate the impact of the retromolar foramen in human mandibles of adult Brazilians and discuss the clinical and ethnic related to the presence of this foramen. Were evaluated 222 human mandibles, dry, adults, Brazilians, independent of gender. The evaluation was performed by two examiners who standardized search from a previous anatomical study. The mandibles were analyzed: the presence of the retromolar foramen (bilateral or unilateral), the presence of the foramen on right and left sides, and the number of foramens present on each side. It was found that 59 had at least one mandible retromolar foramens resulting in an incidence of 26.58%. The retromolar foramen was present unilaterally in 41 mandibles and 18 bilaterally, with incidences of 18.47% and 12.16% respectively. On the right side, the retromolar foramen was present in incidences of 16.22% and 18.92% respectively. The analysis of the right side of the mandibles revealed that 47.46%, 21.21% and 3.03% had one, two and three foramens, respectively. The left side showed 55.93%, 16.22% and 8.11% of the 222 mandibles with one, two and three retromolar foramens, respectively. The incidence of retromolar foramen in the Brazilian population is significant and should be considered in the planning and execution of procedures in several areas of clinical practice dentistry in order to avoid complications. Moreover, it was found that the incidence of retromolar foramen contributes to differentiation of ethnic groups in the area of forensic anthropology. ˚

Caroticoclinoid foramen in human skulls: incidence, morphometry and its clinical implications

The caroticoclinoid foramen is an inconstant structure, formed by the union of the anterior and middle clinoid processes. The aim of this study was to perform an incidence and morphometry of the caroticoclinoid foramen in Brazilian human skulls and discuss its clinical implications. Eighty dry human skulls with sex distinction were used, and 3 groups of incidence were determined: General, sex, and sides. The morphometry was performed using a manual caliper and the major diameter of the foramina was measured; the values were also divided in general, according to sex and sides. The incidence of skulls with at least one foramen was 8.5%. According to the sides, 8.5% of the skulls showed foramen on the right side and 2.5% on the left. We found 2.5% of the skulls with bilateral foramen and 6.25% with unilateral foramen. In relation to sex, the foramens were found in 5% of male skulls and 12.5% of female skulls. The major diameter of this structure presented on mean, values of 5.23 mm on general, 5.18 mm on the right side and 5.35 mm on the left, 5.30 mm in male skulls and 5.18 mm in female skulls. The anatomical characteristics of this foramen should be considered in view of its clinical implications associated with neurosurgery as clinoid process removal, and symptoms as headache due to internal carotid artery alterations in this region. In conclusion knowledge of this structure supports the diagnosis and treatment of clinical complications related to this variation.

Cross-sectional study of correlation between mandibular incisor crowding and third molars in young Brazilians

Objectives: The aim of this study was to evaluate transversally the clinical correlation between lower incisor crowding and mandible third molar. Study Design: Three hundred healthy volunteers (134 male and 166 female), aged 20.4 (±2.4) years-old were submitted to a complete clinical examination and filled up a questionnaire about gender, age, total teeth number and presence or absence of superior and inferior third molar. After a recent panoramic radiography were evaluated. The multiple logistic regression showed that none of the studied factors influenced the mandibular incisor crowding. Results: The proportion of both molars present or both absent was higher than the other conditions (Chi-square, p<.0001). The multiple logistic regression showed that any of the studied factors, influenced (p>.05) the mandibular incisor crowding. Despite the statistical significance, wear orthodontics appliances showed a little correlation (odds ratios < 1.0) in the mandibular incisor crowding. Conclusion: Presence of maxillary and/or mandibular third molars has no relation with the lower incisor crowding. Key words:Malocclusion, third molars, lower incisor crowding, mandible.

The effects of strength training and raloxifene on bone health in aging ovariectomized rats

The aim of this study was to investigate the effects of strength training (ST) and raloxifene (Ral), alone or in combination, on the prevention of bone loss in an aging estrogen-deficient rat model. Aging Wistar female rats were ovariectomized at 14months and allocated to four groups: (1) non-trained and treated with vehicle, NT-Veh; (2) strength training and treated with vehicle, ST-Veh; (3) non-trained and treated with raloxifene, NT-Ral; and (4) strength training and treated with raloxifene, ST-Ral. ST was performed on a ladder three times per week and Ral was administered daily by gavage (1mg/kg/day), both for 120days. Areal bone mineral density (aBMD), strength, microarchitecture, and biomarkers (osteocalcin, OCN; osteoprotegerin, OPG; and tartrate-resistant acid phosphatase, TRAP) were assessed. Immunohistochemistry was performed for runt-related transcription factor 2 (RUNX2), osterix (OSX), OCN, OPG, TRAP, and receptor activator of nuclear factor kappa-B ligand (RANKL). The rats that performed ST (ST-Veh) or were treated with Ral (NT-Ral) showed significant improvements in aBMD (p=0.001 and 0.004), bone strength (p=0.001), and bone microarchitecture, such as BV/TV (%) (p=0.001), BS/TV (mm(2)/mm(3)) (p=0.023 and 0.002), Conn.Dn (1/mm(3)) (p=0.001), Tb.N (1/mm) (p=0.012 and 0.011), Tb.Th (1/mm) (p=0.001), SMI (p=0.001 and 0.002), Tb.Sp (p=0.001), and DA (p=0.002 and 0.007); there was also a significant decrease in plasma levels of OCN (p=0.001 and 0.002) and OPG (p=0.003 and 0.014), compared with animals in the NT-Veh group. Ral, with or without ST, promoted an increased immunolabeling pattern for RUNX2 (p=0.0105 and p=0.0006) and OSX (p=0.0105), but a reduced immunolabeling pattern for TRAP (p=0.0056) and RANKL (p=0.033 and 0.004). ST increased the immunolabeling pattern for RUNX2 (p=0.0105), and association with Ral resulted in an increased immunolabeling pattern for OPG (p=0.0034) and OCN (p=0.0024). In summary, ST and Ral administration in aged, estrogen-deficient Wistar female rats is associated with a decrease in bone turnover marker plasma levels, increased activity of cells that promote osteoblastogenesis, and decreased activity of cells that promote osteoclastogenesis; these are correlated with higher aBMD, bone strength, and bone microarchitecture at the femoral neck. The results indicate that strength training and Ral are potential tools to reduce the risk of fractures at clinically relevant sites.

Comparison of gunshot entrance morphologies caused by .40-caliber Smith & Wesson, .380-caliber, and 9-mm Luger bullets: a finite element analysis study.

Firearms can cause fatal wounds, which can be identified by traces on or around the body. However, there are cases where neither the bullet nor gun is found at the crime scene. Ballistic research involving finite element models can reproduce computational biomechanical conditions, without compromising bioethics, as they involve no direct tests on animals or humans. This study aims to compare the morphologies of gunshot entrance holes caused by.40-caliber Smith & Wesson (S&W), .380-caliber, and 9×19-mm Luger bullets. A fully metal-jacketed.40 S&W projectile, a fully metal-jacketed.380 projectile, and a fully metal-jacketed 9×19-mm Luger projectile were computationally fired at the glabellar region of the finite element model from a distance of 10 cm, at perpendicular incidence. The results show different morphologies in the entrance holes produced by the three bullets, using the same skull at the same shot distance. The results and traits of the entrance holes are discussed. Finite element models allow feasible computational ballistic research, which may be useful to forensic experts when comparing and analyzing data related to gunshot wounds in the forehead.

Stress Distribution in Human Zygomatic Pillar Using Three-Dimensional Finite Element Analysis

El objetivo de este articulo fue analizar la distribucion de la tension en el pilar cigomatico humano durante la contraccion del musculo masetero utilizando analisis de elementos finitos tridimensionales. Un modelo de tres dimensiones de dientes del hemicraneo facial fueron producidos sobre la base de datos de CT-scan. Se utilizo como modelo un craneo adulto de sexo masculino con la integridad de la anatomia estructural. Fuerzas musculares se aplicaron en el origen de los ascensores de los musculos de la mandibula y soportes se aplicaron a la superficie oclusal del primer y segundo molar para simular una carga masticatoria y estimular el pilar cigomatico. Condiciones de simetria se colocaron en el plano mediano. Se utilizaron restricciones en los planos superior y posterior. El analisis de las tensiones equivalentes von-Mises y maximo director se realizo a traves del campo de esfuerzos a lo largo del pilar cigomatico. Fue representada la concentracion de esfuerzos en el proceso alveolar, hueso cigomatico, proceso frontal y temporal del hueso cigomatico y el arco superciliar. La linea de tension indica la distribucion de la tension del maxilar hacia el hueso frontal y temporal. Las tensiones se produjeron debido a las fuerzas oclusales resultantes, que se apoyan principalmente por el hueso cigomatico, distribuidas de manera no uniforme y sobre todo a traves del pilar cigomatico. Este estudio ha contribuido a una mejor comprension de la distribucion de la tension en el pilar cigomatico para entender la influencia de la masticacion sobre la morfologia de este pilar y ser de utilidad en la practica clinica.

Assessment of the differences in masticatory behavior between male and female adolescents.

Chewing behavior may show sex differences; thus, the present study aimed to compare the masticatory aspects and the prediction of masticatory performance between male and female adolescents. Ninety-one healthy subjects (47 girls, 44 boys), caries-free and aged 14-17years, were included. Masticatory performance and maximal bite force were evaluated using a color-changeable chewing gum and digital gnathodynamometer, respectively. Masticatory behavior was assessed by the subjective aspect of the quality of the masticatory function (validated questionnaire) and the Orofacial Myofunctional Evaluation with Scores expanded (OMES-e) was used to determine chewing time, frequency of chewing cycles and other aspects. Salivary flow rate was also assessed. The physical examination involved measurements of facial morphometry, body weight, height, skeletal muscle mass, and dental/occlusal evaluations. It was observed that boys showed larger facial dimensions, higher bite force and chewing frequency and better masticatory performance than girls. They also showed shorter chewing time, fewer chewing cycles and lower score for OMES-e (that is, more changes in orofacial myofunctional aspects). Bite force showed a weak correlation with skeletal muscle mass only in boys (r=0.3035; p=0.0451). The masticatory performance was dependent on the bite force in boys (Adj R(2)=19.2%; Power=84.1%); among girls, masticatory performance was dependent on the frequency of chewing cycles and masticatory behavior (subjective aspect) (Adj R(2)=34.1%; Power=96.1%). The findings support the existence of sex differences in many masticatory aspects of function and behavior, hence the importance of considering sex differences when evaluating masticatory function and myofunctional therapy outcomes among young subjects.

Forámenes Emisarios del Cráneo Humano: Características Anatómicas y sus Relaciones con la Neurocirugía Clínica

Department of Morphology State University of Campinas - UNICAMP, Anatomy Area, Piracicaba, SP

Review of In Vivo Bone Strain Studies and Finite Element Models of the Zygomatic Complex in Humans and Nonhuman Primates: Implications for Clinical Research and Practice.

The craniofacial skeleton is often described in the clinical literature as being comprised of vertical bony pillars, which transmit forces from the toothrow to the neurocranium as axial compressive stresses, reinforced transversely by buttresses. Here, we review the literature on bony microarchitecture, in vivo bone strain, and finite‐element modeling of the facial skeleton of humans and nonhuman primates to address questions regarding the structural and functional existence of facial pillars and buttresses. Available bone material properties data do not support the existence of pillars and buttresses in humans or Sapajus apella. Deformation regimes in the zygomatic complex emphasize bending and shear, therefore conceptualizing the zygomatic complex of humans or nonhuman primates as a pillar obscures its patterns of stress, strain, and deformation. Human fossil relatives and chimpanzees exhibit strain regimes corroborating the existence of a canine‐frontal pillar, but the notion of a zygomatic pillar has no support. The emerging consensus on patterns of strain and deformation in finite element models (FEMs) of the human facial skeleton corroborates hypotheses in the clinical literature regarding zygomatic complex function, and provide new insights into patterns of failure of titanium and resorbable plates in experimental studies. It is suggested that the “pillar and buttress” model of human craniofacial skeleton function be replaced with FEMs that more accurately and precisely represent in vivo function, and which can serve as the basis for future research into implants used in restoration of occlusal function and fracture repair. Anat Rec, 299:1753–1778, 2016.

Computer Graphics Applied to Anatomy: A Study of two Bio-CAD Modeling Methods on Finite Element Analysis of Human Edentulous Hemi-Mandible

Univ Estadual Campinas, Piracicaba Dent Sch, Anat Area, Dept Morphol, Piracicaba, SP, Brazil