Cerebellar volume in early-onset schizophrenia and its association with severity of symptoms.

OBJECTIVES: This study aimed to investigate whether early-onset schizophrenia (EOS) cases differ from controls regarding volumes of the total cerebellum and the right and left cerebellar hemispheres, and volumetric asymmetry. Correlations of cerebellar volumes and asymmetry indices with severity of symptoms and general functioning in cases of EOS were also assessed. METHODS: Adolescents with EOS (n = 23) were compared with controls (n = 23). Sociodemographic and clinical data, and magnetic resonance imaging scans that were acquired for routine clinical purposes were collected retrospectively. Cerebellar volumes were evaluated using the stereological method. Asymmetry indices were subsequently calculated. Scores of the Positive and Negative Syndrome Scale and the Children's Global Assessment Scale were used to assess the severity of symptoms and general functionality. RESULTS: There were no significant differences in any of the cerebellar volumes and asymmetry indices between the two groups. Neither cerebellar volumes nor asymmetry indices were correlated with the severity of symptoms and general functionality in EOS. CONCLUSIONS: Our findings suggest that the early-onset form of schizophrenia does not show apparent volumetric changes of the cerebellum. Additionally, the neural circuits involved in formation of symptomatology may not reflect any correlation with cerebellar volumes at mid-adolescence.

Comparison of Three Methods Used for Estimating Area of Foramen Magnum.

OBJECTIVE: To compare whether there are any differences between the 3 methods used for measure area of foramen magnum (FM) in skulls. METHODS: The FMs of 150 skulls were examined. Antero-posterior diameter, transverse diameter were measured using by Vernier caliper. The area of the FM was calculated by using 2 different formulas as described previously by Radinsky and Teixeira.The authors also applied stereological assessment method for estimating the surface area of FMs. The area was calculated 3 times manually using stereological point grid system for each skull.The authors compared the mean surface area of FMs obtained from each of these 3 methods estimating surface area of FMs whether there were any significant differences in between their results. RESULTS: The mean areas of the FMs estimated according to Teixeria formula, Radinsky formula, and Cavalieri stereological method were respectively as follows: 790.47 ±â€Š99.86 mm, 783.66 ±â€Š99.34 mm, and 748.06 ±â€Š100.19 mm. The authors observed significant differences (P < 0.05) in between the mean surface areas of FMs obtained from each of these 3 methods used for estimating the area. CONCLUSION: There were significant differences (P < 0.05) in between the mean surface areas of FMs obtained from each of these 3 methods used for estimating the area.

Morphometrical aspect on angular branch of facial artery.

Anatomic variability and anastomosis of the angular artery of the facial artery with the other arteries are important for both anatomists and surgeons. In particular, the angular artery is a significant landmark in dacryocystorhinostomy. Because of variations on anatomy of the angular artery, there are limited numbers of anatomic studies on the flaps of facial region. Hence, the aim of the cadaveric study was to evaluate the anatomic features of the angular artery in detail to help surgical procedures.The artery was represented under ×4 loop magnification in 32 sides of 16 formalin-fixed adult cadavers. The angular artery's position, diameter, and branch patterns relevant to the nose arterial supply were evaluated. The facial artery ended symmetrically in 10 (62.5%) of the cadavers. The facial artery was terminated as angular artery in all of the cases. The types of the angular artery were as follows: classical angular type in 8 cases (25.0%), nasal type in 15 cases (46.9%), alar type in 4 cases (12.5%), and labial type in 5 cases (15.6%) on the facial halves. We studied the topographic anatomic features of the angular artery for increasing reliability of the flaps on the region. The angular arterial anatomic details are critical and essential for surgical cosmetic and functional results.

The volume of experimental design cerebellum: stereological microanatomic study.

Cerebellum is responsible to higher cognitive functions and delicate motor activity. Because of its significance, cerebellum may play a major role in cognitive, behavioral, and psychiatric diseases. Therefore, the investigations on cerebellum may be contributed to the future researches so as to solve reasons of the diseases. The rabbit brain relatively larger than the rat and mouse brain and the individual evaluation of its subdivisions are rather easy. There are no data on cerebellar volume of rabbits in literature. Thus, the study presents microscopic volume calculation of rabbits' cerebellum using the stereological method. The mean (SD) calculated volume of the cerebellum in the rabbit brain was found to be 0.69 (0.03) cm3. The individual microscopic volume estimation of an animal subject can be achieved by Cavalier method. Researchers believed that the findings and the applied method in this study may be useful for the scientists.

The volume prediction on the experimental design hippocampus using stereological method.

The application of stereologic techniques to the analysis of the nervous system has greatly contributed to the evaluation of the normal and pathological anatomy of the aging brain. Currently, the hippocampus still holds secrets about the aging process. Experimental researches on hippocampus morphology may contribute to the future researches. This study presents the volume and weight of left hippocampus using a stereological technique on light microscope. The mean weight of the encephalon without cerebellum was 6.1 ± 0.1 g. The mean weight and the volume of the hippocampus were (mean ± SD) 0.28 ± 0.02 g and 0.28 ± 0.02 cm3, respectively. The mean coefficient of error for the stereological volume estimation of the hippocampus was 0.03. The individual volume estimation of the subjects may be achieved by the Cavalieri method. Investigators believed that the findings and the applied technique in this study may be useful for clinicians.

Investigation of temporal bone asymmetry in cases with unilateral tinnitus: morphometric and multicentric clinical study.

The aim of this multicentric study was to compare the anatomical structures of temporal bone in patients with unilateral tinnitus with their healthy ears. We also aimed at evaluating whether age and gender-related asymmetrical changes occur in temporal bones or not. Fifty two ears of 26 patients who had unilateral tinnitus were included into the retrospective study. The patients who had subjective nonpulsatile tinnitus and who previously had temporal computed tomography according to their file records were accepted to study. Temporal CT scans and audiometric results of patients were examined retrospectively. Middle ear volume, diameter of internal acoustic meats and diameter of jugular bulb were evaluated by both anatomist and radiologist, interobserverly. Internal acoustic meats and jugular bulb were found larger in the ears that had tinnitus than healthy ears; however, there was no statistically significance. The stereological morphometrical study of temporal bone asymmetry in humans correlate with sex is of importance for both otolarygologs and anatomists. These results will contribute to data on middle ear volume, internal acustic meats and jugular bulb sizes.

Ocular and periocular injuries associated with an isolated orbital fracture depending on a blunt cranial trauma: anatomical and surgical aspects.

The anatomical location of fractures following blunt cranio-orbital trauma is important for neurosurgeons and maxillofacial surgeons. In this study, 588 cranio-orbital fractures following blunt trauma were evaluated retrospectively with regard to the anatomical site and surgical treatment. Orbital cranial nerve injuries and the outcomes of the medical and/or surgical treatment are described. Distribution of the zygomatic complex and orbital fractures were as follows: zygomatic complex fractures (n:304), isolated orbital fractures (n:58), complex comminuted fractures (n:226). In 58 cases, 69 orbit fractures were found (11 bilateral and 47 unilateral fractures). The lateral wall was the most frequent fracture (n:63). The least frequent fracture was the roof of the orbit (n:11). The accompanying lesions were as follows: 89.65% of cases were associated with periorbital haematoma (n:52), 13.79% of cases with retrobulbar haemorrhage (n:8), 96.55% cases with periorbital soft tissue oedema (n:56), 53.45% cases with pneumocephalus (n:31), 8.62% cases with intra-parenchymal contusion (n:5), 6.89% cases with enophthalmia (n:4), 5.17% of cases with rhinorrhoea (n: 3), 5.17% cases with optic bulb injury and adnexial trauma (n:3), 32.76% cases with intra-orbital emphysema (n:19), and 20.69% with vision dysfunctions (n:12), of whom 2 had no optic nerve injury.

Stereological volumetric evaluation of the cerebellum in benign paroxysmal positional vertigo.

OBJECTIVE: To evaluate cerebellar volume changes and the asymmetry of patients with benign paroxysmal positional vertigo (BPPV). METHODS: The cerebellar hemispheres` volumetric symmetry were evaluated using a stereological method on MR images. The study included 15 patients with BPPV, and 14 age-, and gender-matched control subjects. The cases were admitted to the Departments of Otolaryngology, Neurology, and Neurosurgery in the Faculty of Medicine, Kocatepe University, Afyonkarahisar, Turkey with the complaint of vertigo between January 2004 and December 2008. RESULTS: The right hemi cerebellum volumes of the subjects with BPPV and the controls were measured smaller than the left hemi cerebellar volumes, however, there was no statistically significant quantitative evidence detected in terms of cerebellar asymmetry between sagittal and axial plane estimates in the cases with vertigo. There was statistical significance between the right and left cerebellum in both the patient and control groups (p=0.023), however, the difference did not change according to gender. There were no statistically significant age and gender dependent cerebellar atrophy and asymmetry between BPPV and control subjects. CONCLUSION: There was no cerebellar atrophy and asymmetry between BPPV and age matched control groups. The stereological evaluation of hemi cerebellar symmetry and atrophy in humans is important for both clinicians and anatomists. The technique is simple, inexpensive, and reliable.

Unusual scalp metastasis from follicular thyroid carcinoma.

Metastatic tumors presenting as soft tissue lesions are relatively rare, and can be the source of diagnostic confusion both clinically and histopathologically. We present a case of an 82-year-old woman with complaints of painless swelling in the right temporo-occipital junction for 3 months, and with unusual scalp metastasis of thyroid follicular carcinoma. Use of histopathological examinations are significant for determining the tumor type, and arriving at the exact and correct diagnosis.

Lumbar vertebra morphometry and stereological assesment of intervertebral space volumetry: a methodological study.

The use of technology in the treatment of degenerative spinal diseases has undergone rapid clinical and scientific development. It has been extensively studied in combination with various techniques for spinal stabilization from both the anterior and posterior approach. Minimally invasive and instrumental approach via posterior fixation is increasingly being used for the treatment of adult degenerative disc disease, stenosis, and deformity of the lumbar vertebrae. Posterior access to the lumbar disc spaces for posterolateral fusion scan has been technically challenging, frequently requiring the use of an approach surgery for adequate exposure. For successful surgery and suitable instrumental design, adequate anatomical knowledge of the lumbar vertebra is also needed. Anatomic features of lumbar vertebrae are of importance for posterior screw fixation technique. The morphometry of L1-L5 has been studied to facilitate the safe application of pedicle screws. Thus, we aimed to evaluate the morphometric landmarks of lumbar vertebrae such as pedicle, vertebral body, vertebral foramen, intervertebral space height and volume for safe surgical intervention using a posterior fixation approach to offer anatomical supports for lumbar discectomy, stenosis and cases of deformity. The features of the L1-L5 vertebral body, the detailed morphometric parameters of lumbar vertebrae and the intervertebral space were analyzed using computerized tomography scan, magnetic resonance imaging and also dry lumbar vertebrae. Additionally, intervertebral space volumes were measured using stereological methods to ensure safe surgical intervention.

Relation of discoid lateral meniscus and cord-like anterior intermeniscal ligament: morphological and clinical study.

Discoid lateral meniscus is a rare disorder and its association with other variations in the knee joint has been reported. The anterior intermeniscal ligament has also been described as connecting the anterior convex margin of the lateral meniscus to the anterior horn of the medial meniscus. In the normal population, it was observed at 53-94%. Although the functional properties of the anterior intermeniscal ligament are not yet clarified, two distinct types of the ligament have been described according to their morphological characteristics as cord-like and membranous types. The purpose of this study was to evaluate any possible association between morphologic types of anterior intermeniscal ligament and discoid lateral meniscus. A retrospective study was designed; 20 discoid lateral menisci were operated using routine arthroscopic examination. Upon arthroscopic examination the thickness of the ligament and associated morphological changes were recorded systematically. The cord-like anterior intermeniscal ligament was an associated structure in 15 of the 20 knees with discoid lateral meniscus (75%). Patients with discoid lateral meniscus apparently have cord-like type anterior intermeniscal ligament, thus we conclude that cord-like type of anterior intermeniscal ligament is a frequent accompanying structure to discoid lateral meniscus and may have a potential stabilizing effect on its anterior stability.

Evaluation of lumbar vertebral body and disc: a stereological morphometric study / Evaluación del cuerpo y disco vertebral lumbar: estudio morfométrico estereológico

Anterior access to the L1-L5 vertebrae and disc spaces can be technically challenging, frequently requiring the use of an approach to a surgeon for an adequate exposure. The technique is used for lesion excision, corpectomy, vertebral body reconstruction with cages, realignment, and/or plating or screwing. For a successful anterior approach and a suitable instrumental design via screw, adequate morphometric knowledge about body of lumbar vertebrae and disc spaces and standardized volumetric data are also required for neurosurgeons. We aimed morphometric and volumetric evaluation of lumbar bodies and discs to contribute to a safe anterior approach during surgery. We evaluated vertebral body and disc morphometry using stereology in right-handed 25 adult subjects on MRI in the same population with no history of vertebral fractures and degenerative spinal disease. The shape, defining concavity index and volumetric measurements of the body L1-L5 vertebrae, morphometric parameters such as length, height, width of the vertebral body were measured. Also morphometric and volumetric analysis of discs between L1 and L5 were evaluated selected axial and sagittal slices. As expected, the average dimensions of male vertebrae are greater than those of females, but most of them do not differ statistically. Only three dimensions, the mean difference between anterior and central heights of L3, L4 and L5 showed statistically significant difference, indicating smaller central height in both males and females.The transverse and anterior-posterior diameters of the vertebral body, intervertebral disc height and volume displayed no sexual dimorphism (p>0.05). But, the intervertebral disc height and volume increased from L1 to L5 (p <0.01). Concavity indexes for all lumbar vertebrae for both sexes did not differ statistically. The method is important to estimate applying implant size and amount in decompression operations for neurosurgeons.

El acceso anterior a las vértebras L1-L5 y espacios entre los discos puede ser técnicamente difícil, con frecuencia requiere la participación de un cirujano para una exposición adecuada. La técnica se utiliza para la extirpación de la lesión, corpectomía, la reconstrucción del cuerpo vertebral con jaulas, realineamiento y / o placas o tornillos. Para un enfoque exitoso anterior y un diseño adecuado instrumental a través de tornillo, un acabado conocimiento sobre la morfometría del cuerpo de las vértebras lumbares y de los espacios entre los discos y la evaluación volumétrica son necesarias para el neurocirujano. El objetivo fue la evaluación morfométrica y volumétrica de los cuerpos lumbares y los discos, para contribuir al abordaje seguro durante la cirugía. Se evaluó en 25 sujetos adultos, diestros, sin antecedentes de fracturas vertebrales y de enfermedad degenerativa espinal, el cuerpo vertebral y la morfometría del disco mediante estereología con RM. La forma de las vértebras, el índice de concavidad y la definición de las medidas volumétricas de los cuerpos L1-L5. Además, se midieron los parámetros morfométricos como longitud, altura, ancho del cuerpo vertebral. Se efectuó un análisis morfométrico y volumétrico de loss cortes axiales y sagitales de los discos entre L1 y L5. Como era de esperar, las dimensiones promedio de las vértebras en los hombres fueron mayores que en las mujeres, pero la mayoría de ellos no son estadísticamente significativas. Sólo tres dimensiones, la diferencia promedio entre la altura anterior y central de las vertebras L3, L4 y L5 mostraron diferencias estadísticamente significativas, indicando menor altura central tanto en los hombres como en las mujeres. Los diámetros transversal y anteroposterior del cuerpo vertebral, la altura del disco intervertebral y el volumen no mostraron dimorfismo sexual (p> 0,05). Sin embargo, aumentaron la altura del disco intervertebral y el volumen de L1 a L5 (p< 0,01). Los índices de concavidad...

Evaluation of cerebellar and cerebral volume in migraine with aura: a stereological study.

Migraine is associated with an increased risk of deep white matter lesions and subclinical posterior circulation infarcts. A significant association between deep white matter hyperintensities and cerebral atrophy is true for various neurological diseases; it was not specifically proven in migraine. The aim of this study was to evaluate the cerebellar and cerebral volume and volume ratios for cerebellum using the Cavalieri principle. We also aimed to examine whether migraine with aura causes cerebellar and cerebral atrophy. Twenty three right-handed patients with migraine with aura diagnosed by means of the International Headache Society criteria and 24 age-matched subjects whose only health problem was headache due to rhinosinusitis and tension type headache were included in the study. Measurements of the cerebellar and cerebral volumes as well as cerebellar/cerebral volume ratios were made using Cavalieri's principle by utilizing the point-counting methods. There were no significant differences between the volumes of cerebrum, cerebellum, and the ratio of cerebellum to cerebrum for males (p = 0.05, p = 0.10, and p = 0.64, respectively) and for females (p = 0.18, p = 0.89, and p = 0.24, respectively). Our results suggest that patients with migraine with aura do not have a significant difference in cerebellar and cerebral volumes and cerebellar/cerebral volume ratios compared to the non-migraine group.

Effect of ligamenta flava hypertrophy on lumbar disc herniation with contralateral symptoms and signs: a clinical and morphometric study.

INTRODUCTION: The purpose of this study was to determine whether ligamentum flavum hypertrophy among disc herniated patients causes contralateral pain symptoms. For this reason we measured the thickness of the ligament in disc herniated patients with ipsilateral or contralateral symptoms. MATERIAL AND METHODS: Two hundred disc herniated patients with ipsilateral symptoms as group I were compared with five disc herniated patients with only contralateral symptoms as group II. Ligamenta flava thicknesses and spinal canal diameters of both groups were measured on magnetic resonance imaging (MRI) with a micro-caliper. RESULTS: Both groups underwent surgery only on the disc herniated side. The total thicknesses of the ligamenta flava in group II was thicker than in group I. There was no spinal stenosis in either group and no significance difference between the groups. Statistically significant differences were found for both ipsilateral and contralateral thickness of the ligament flava in both groups. We also compared thickness of the ligamenta flava for each level of disc herniation in group I; ligamenta flava hypertrophy was more common at L3-L4 and L4-L5 levels of vertebrae in females. CONCLUSIONS: Aetiology of contralateral sciatica among disc herniated patients may be related to hypertrophy of the ligamenta flava, especially on the opposite side. Surgical approaches of the disc herniated side alone may be sufficient for a good outcome.

Clinical and stereologic evaluation of osteochondroma.

Osteochondroma is a benign tumor that is unusual in the maxillofacial region. Anatomy of the region, especially the mandible, is important for surgical intervention for the condylar osteochondroma. The present case report describes evaluation of condylar hyperplasia with emphasis on the advantages and disadvantages of sterolithographic solid model and stereologic techniques for preoperative surgical planning, operation time, and prognosis. Condylar osteochondoma was diagnosed by panoramic radiograph and 3-dimensional computerized tomography (3DCT) as well as histopathologic analysis in a male patient. Before surgery, a stereolithographic model was created and stereologic method was used based upon 3DCT.

Evaluation of cerebellar asymmetry in Alzheimer's disease: a stereological study.

OBJECTIVES: Alzheimer's disease (AD) is the most common cause of dementia and, as previous studies have indicated, degenerative changes in the cerebellum occur in AD. It is well known that the cerebellum does not have a symmetric morphology and some pathological disorders, such as schizophrenia, epilepsy, autism and alcoholism, can cause asymmetrical changes in the cerebellum. In this study, we aimed to evaluate whether or not patients with AD show cerebellar asymmetry. We also intended to depict the probable volumetric asymmetry by using a stereological technique. MATERIALS AND METHODS: The study evaluated the volumetric measurements of each cerebellar hemisphere by applying a stereological method to MR images. This age- and gender-matched study was composed of 15 patients with probable AD and 14 healthy subjects (controls). MR images were analyzed by using the point-counting approach, holding to Cavalieri's principle. RESULTS: Although there was significant cerebellar atrophy in AD patients, the study showed no statistically significant cerebellar asymmetry according to age and gender, both in the study and control groups (p > 0.05). CONCLUSIONS: There was no difference in cerebellar asymmetry associated with age and gender between the AD patients and control subjects. The stereological evaluation of cerebellar asymmetry correlating with gender is of importance to both clinicians and anatomists. The technique is simple, inexpensive, reliable and unbiased.

Anatomic evaluation of maxillary sinus septa: surgery and radiology.

The anatomical structure of the maxillary sinus is fundamental to maxillofacial surgery. The presence of septa, located at the inner surface of the maxillary sinus, increases the risk of sinus membrane perforation during sinus elevation for dental implant surgery. The aim of this study was to evaluate the anatomy of maxillary sinus septa.Data in this study was obtained from a total of 205 cases. One hundred and seventy-seven patients were partially edentulous (PE) whereas 28 patients had no teeth. Dental computerized tomography (dental CT) was used in the assessment of 410 sinus segments (205 left and 205 right segments). The prevalence of sinus segments with septa was found to be 145/410. Septa were detected in 91 of the 177 PE cases. There were a total of 26 septa in 18 of the 28 completely edentulous (CE) cases. A total of 165 septa were detected in these segments. The prevalence of septa was 46.4% (26/56) in the CE, and 39.2% (139/354) in the PE segments. Thirty septa were found in the anterior, 110 in the middle and 25 in the posterior region. All detected septa were located mediolateral direction. Their relative position: lateral, middle or medial were also noted. The height measurements of the septa varied amongst the different positions. In view of the fact that septa of various heights and courses can develop in all parts of the maxillary sinus, timely and adequate assessment of the inner aspect of the maxillary sinus is essential to avoid complications during sinus augmentation procedures.

The premasseteric branch of facial artery: its importance for craniofacial surgery.

AIM: The masseter muscle is often exploited by craniofacial surgeons in transposition operations to correct facial palsy, benign masseteric hypertrophy; or neurectomy-induced atrophy of the muscle. A clear understanding of the course of the premasseteric branch of the facial artery and its relations with adjacent structures is essential in maneuvering the masseter muscle safely. In the present study the premasseteric branch was analyzed in details. MATERIAL AND METHODS: Neurovascular and anatomical features and relations of the premasseteric branch and its branches were evaluated according to location, origin, diameter, length and course by bilateral meticulous anatomic micro dissection under 4x loop magnification in formalin fixed 14 adult preserved cadavers. RESULTS: The premasseteric branch originated separately from the facial artery in all cases. The course of the branch was observed to the upper anterior border of the masseter muscle. The diameter of the premasseteric branch was 1.12 mm (mean) at the level of origin. The diameter of the premasseteric branch was larger than the facial artery in 3% of cases. The location of the branch was defined according to body of the mandible. Branches and anastomoses of the premasseteric branch were also represented. CONCLUSION: Anatomical data of the premasseteric branch will help craniofacial surgeons elevate flaps safely.

Multiple abnormal unerupted mandibular permanent molar teeth: a case report / Molares mandibulares anormales no-erupcionados múltiples: reporte de un caso

Abnormal multiply unerupted permanent molars have long received the attention of anatomists and maxillofacial surgeons besides the other developmental teeth anomalies. This paper presents a clinical case of a 23-year-old male patient who was admitted to the department of maxillofacial surgery in faculty of dentistry in Gulhane Medical School with a six month history of pain at the rest position and during chewing and also tender on his right corpus of mandible. The impaction which resulted in eruption failure and anatomical dislocation of the normally developed three mandibular molar teeth was found. It was defined facial asymmetry on his right side in extra-oral examination. Diagnosis of multiple abnormal unerupted mandibular molar teeth was confirmed by panoramic and 3D CT images. The unerupted inverted tooth was the third molar which is positioned to basis of the mandible on the right side. In the other side, the first molar was placed on basis of mandible and located distoangulary. The second molar was located on middle of the left corpus mandible vertically. And also, the third molar was erupted mesioangulary. The arch-length was evaluated by the oral surgeon. Mesio-distal distance between the teeth was to be sufficient. Causes of impacted permanent teeth might have been influenced by local factors such as prolonged deciduous tooth retention, malposed tooth germs, but not causing arch-length deficiency and supernumerary teeth. Abnormalities such as those reported in the present case are significant during maxillofacial surgery.

Los molares permanentes anormales no erupcionados múltiples, además de otras anomalías del desarrollo de los dientes, desde hace tiempo han recibido atención de anatomistas y cirujanos maxilofaciales. Este artículo presenta un caso clínico de un paciente masculino de 23 años de edad, que fue admitido en el Departamento de Cirugía Maxilofacial de la Facultad de Odontología de la Escuela de Medicina Gulhane, con una historia de seis meses de dolor, en la posición de descanso y durante la masticación, así como dolor en su cuerpo mandibular derecho. Fue encontrada la impactación que resulta de la falla en la erupción y la dislocación de la anatomía normal del desarrollo en tres molares mandibulares. En el examen extraoral fue definida asimetría facial del lado derecho. El diagnóstico de molares mandibulares anormales no erupcionados múltiples fue confirmado por radiografía panorámica e imágenes de tomografía 3D. El diente invertido no erupcionado fue el tercer molar que se encontró en la base de la mandíbula en el lado derecho. En el otro lado, el primer molar se posicionó sobre la base de la mandíbula distoangularmente. El segundo molar se encontró verticalmente en medio del cuerpo mandibular izquierdo. También, el tercer molar erupcionó mesioangularmente. La longitud del arco fue evaluada por el cirujano oral. La distancia mesio-distal entre los dientes fue suficiente. Las causas de impactación de los dientes permanentes podrían haber sido influenciadas por los factores locales, tales como la retención prolongada de dientes deciduos o gérmenes dentales malposicionados, pero no fueron provocados por deficiencia de longitud del arco y dientes supernumerarios. Anomalías tales como las reportadas en el presente caso, son importantes en la cirugía maxilofacial.