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.

SUMMARY:The recognition of emissary foramens is important not only for understanding the regional neurovascular anatomy, but also to distinguish normal from potentially abnormal structures. Thus, the aim of this study was to review the literature on anatomical and clinical aspects of the mastoid, parietal and sphenoid emissary foramens. It was found that the emissary foramen presents importance in clinical practice because it acts as a route of spread of extracranial infection to the intracranial structures and also possible complications in neurosurgery, due to its influence in the performance of techniques such as radiofrequency rhizotomy for treatment of trigeminal neuralgia. The anatomical knowledge of the emissary foramens is important due to variability in their incidence in the human skull and its relation to the dura mater sinuses. KEYWORDS: Emissary foramens 288less studied by clinical, needs a through approach to avoid interpretation errors during procedures in neurosurgery and clinical dentistry (Sicher & DuBrul, 1977;Gupta et al., 2005;Louis Jr. et al., 2009;Rossi et al., 2010).Considering the importance of knowing the implications of the anatomical variations of the human skull can generate during clinical procedures, the aim of this study was to review the literature on anatomical and clinical aspects of the mastoid, parietal and sphenoid emissary foramens. Literature ReviewMastoid Foramen. The emissary mastoid foramen is located at the mastoid portion of the temporal bone, near to occipitomastoid suture (Fig. 1). This foramen can also appear on the occipitomastoid suture and, if present, transmits an emissary vein to sigmoid sinus. It can occur in single or multiple (Sicher & DuBrul).The mastoid emissary vein may act as another route of spread of infection or tumors originated in the face and infratemporal fossa (Sicher & DuBrul).In addition, the mastoid foramen is considered an anatomical landmark that helps in the differentiation of species and, thus, was verified their importance in forensic anthropology (Reis et al.). It is believed that the adaptation of a bipedal hominid position was associated with anatomical and physiological changes in the venous system of the skull base to adapt to the concomitant changes in intracranial venous blood flow. The pattern of venous drainage of the Australopithecus was based on the occipital vein. In homo sapiens, the volume of this drainage was reduced occurring, thus, the development of new veins. Among these new veins, the emissary mastoid vein led to the emergence of the mastoid foramen in the modern human skull (Falk, 1986).These evolutionary changes have shown that the sigmoid sinus drains into the vertebral venous plexus when is in the upright position and drains into the internal jugular vein when is in the supine position (Goucha et al., 2002). Boyd (1930) found an incidence of 68% of the mastoid foramen in a sample of 1478 skulls of modern human, while Falk obtained a 90% incidence in a sample of 51 skulls of early human. Reis et al., found an inci...

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SUMMARY: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.

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