Width Of Foramen Research Articles

Cyclosporin a-induced new cementum formation: a morphometric evaluation in the periapical region of rats

Cyclosporin A (CsA) is a potent immunosuppressor used in organ transplantation and in the management of various autoimmune diseases. Recent studies have shown that CsA stimulates deposition of cementum on root surfaces. The aim of this study was to evaluate the periapical cementum thickness and the apical foramen width in CsA-treated rats. Rats weighing 50 g were treated with a daily injection of 10 mg/kg body weight of CsA in the chow for 60 days. The cementum of the mandibular 1st molars was histologically and morphometricaly examined by analysis of 5-microm-thick serial buccolingual paraffin sections stained with hematoxylin and eosin. Histometric and stereologic analyses revealed the presence of large amounts of cementum in all root surfaces, particularly abundant in the periapical region and obliterating the foramen. The volume density of cementoblasts did not increase. Five to 90 days after the termination of CsA therapy, there was no reduction of cementum thickness. These results suggest that cementum deposition is not reversible after cessation of CsA treatment.

Human osseous intervertebral foramen width

Alterations of the width of the human intervertebral foramen can play a pathophysiological role in low back pain. Osseous dimensions of the human intervertebral foramen are rarely recorded. Therefore, we present reference data obtained from skeletal samples of known lifestyle, population affinity, sex, and age at death. Cervical, thoracic, and lumbar vertebrae of functional transition zones of 71 macroscopically normal spines from early 19th century AD Swiss burial sites were selected. The intervertebral foramen widths (IFW) were analyzed with respect to possible lateralization and the impact of sex, individual age, and stature. Neither a significant side difference nor a correlation of IFW with individual age or stature could be found. Females show somewhat larger IFW than males, especially in the lumbar region. Data comparisons with earlier studies are limited due to methodological differences and possible interpopulational variations. Furthermore, the osseous intervertebral foramen only reveals a glimpse of the clinically relevant in vivo structure. Nevertheless, more focus on the osseous dimensions of the intervertebral foramen will provide baseline data of this important anatomical landmark. These data could also explore the peculiarities of the intervertebral foramen, such as its reverse sex dimorphism.

Computed tomographic evaluation of lumbar spinal structures during traction

In the previous studies, it is reported that traction diminishes the compressive load on intervertebral discs, reduces herniation, stretches lumbar spinal muscle and ligaments, decreases muscle spasm, and widens intervertebral foramina. The aim of this study was to evaluate the effects of horizontal motorized static traction on spinal anatomic structures (herniated area, spinal canal area, intervertebral disc heights, neural foraminal diameter, and m.psoas diameter) by quantitative measures in patients with lumbar disc herniation (LDH). At the same time the effect of traction in different localizations (median and posterolateral herniation) and at different levels (L4-L5 and L5-S1) was assessed. Thirty two patients with acute LDH participated in the study. A special traction system was used to apply horizontally-motorized static lumbar traction. Before and during traction a CT- scan was made to observe the changes in the area of spinal canal and herniated disc material, in the width of neural foramina, intervertebral disc heights, and in the thickness of psoas muscle. During traction, the area of protruded disc area, and the thickness of psoas muscle decreased 24.5% (p = 0.0001), and 5.7% (p = 0.0001), respectively. The area of the spinal canal and the width of the neural foramen increased 21.6% (p = 0.0001) and 26.7% (p = 0.0001), respectively. The anterior intervertebral disc height remained unchanged with traction however the posterior intervertebral disc height was significantly expanded. This study is the first to evaluated in detail and quantitatively the effect of motorized horizontal lumbar spinal traction on spinal structures and herniated area. According to detailed measures it was concluded that during traction of individuals with acute LDH there was a reduction of the size of the herniation, increased space within the spinal canal, widening of the neural foramina, and decreased thickness of the psoas muscle.

Clinical perspectives on secular trends of intervertebral foramen diameters in an industrialized European society.

Low back pain origins have been a matter of great controversy. While spinal stenosis is now radiologically traceable, the alteration of intervertebral foramen is less clear. The aim of this study was to assess "secular trends"-alterations occurring from one generation to the next-in osseous intervertebral foramina of the major vertebral segments in an industrialized society, and to discuss their possible clinical implication. The macerated "maximum intervertebral foramen width" and "intervertebral foramen height" of all major vertebral levels in 71 non-pathologic Swiss adult skeletons from the nineteenth and early twentieth century, with known individual age and sex and similar geographic and socio-economic background, were measured by sliding caliper at validated landmarks. A secular trend of the increase in "maximum intervertebral foramen width" is found for most levels, with females showing a more prominent alteration. Additionally, the non-pathologic "maximum intervertebral foramen width" does not change with respect to individual age, nor is a significant side difference detectable. "Intervertebral foramen height," hereby defined as the difference of the dorsal vertebral body height minus pedicle height, demonstrates for most levels, and either sex, an insignificant negative secular trend. Neither stature nor skeletal robustness vary significantly through time within this particular sample. The results of this study, despite obvious inadequacies of methods used, exclude secular narrowing of the "maximum intervertebral foramen width" as the only cause of radiculopathy or spinal stenosis. Furthermore, we found a mild insignificant decrease of the clinically more relevant "intervertebral foramen height." Nevertheless, the detected short-time variability of the bony intervertebral foramen, independent of individual stature, skeletal robustness or age, argues for an enhanced focus on the understanding of clinically relevant changes of spinal morphology from generation to generation.

Height Changes of Intervertebral Disc and Neural Foramen after Anterior Lumbar Interbody Fusion in the Lumbar Spine

Study design : A prospective clinical study with radiologic assessment was conducted. Objectives : To analyze the height changes of the intervertebral disc and neural foramen and width changes of the neural foramen after anterior lumbar interbody fusion and posterior fixation in the lumbar spine. Summary of Literature Review : Anterior lumbar interbody fusion distracts the height of the intervertebral disc and neural foramen and the width of the neural foramen. Materials and Methods : Minimal anterior lumbar interbody fusion and posterior fixation were performed in 20 cases from January 1999 to January 2001. The measuring factors were the height of the anterior and posterior discs, and the height and width of the neural foramen, measured with a caliper in 1mm reconstructive, computed tomography, sagittal images before and 6 months after anterior lumbar interbody fusion. The factors were independently measured by three different persons. Results : The height of the anterior and posterior discs was increased by mean 32.2% and 40.5%, respectively. The height of the right and left neural foramen was increased by mean 15.7% and 18.3%, respectively. The width of the superior, middle and inferior neural foramen was increased by mean 20.6%, 30.3% and 38.6%, respectively. There were significant increases in all measuring factors after minimal anterior lumbar interbody fusion. Conclusions : Minimal anterior lumbar interbody fusion significantly increased the height of the anterior and posterior intervertebral discs, and the height and width of the neural foramen, and produced neural decompression.

Location of the Vertebral Artery Foramen on the Anterior Aspect of the Lower Cervical Spine by Computed Tomography

Axial computed tomography scans were performed on 14 cadaveric cervical spines to determine the location of the vertebral artery foramen on the anterior aspect of the lower cervical spine. The best scan through the vertebral artery foramen from each level at C3-C6 was selected. Measurements of the vertebral artery foramen included the foramen depth, foramen width, interforaminal distance, the distance from the anterior border of the transverse foramen to the anterior border of the transverse process, the distance from the posterior border of the transverse foramen to the posterior border of the lateral mass, and the distance from the medial border of the vertebral artery foramen to the lateral border of the vertebral body. The results show that the average transverse foramen width was 5.5 +/- 0.4 mm at C3, 5.7 +/- 1.0 mm at C4, 5.9 +/- 0.7 mm at C5, and 5.7 +/- 0.7 mm at C6. The average transverse foramen depth and average interforaminal distance gradually increased from C3 to C6. The distance from the anterior border of the vertebral artery foramen to the anterior border of the transverse process gradually increased from C3 (1.2 +/- 0.4 mm) to C6 (2.7 +/- 0.8 mm) as well. The average distance between the medial border of the transverse foramina and the lateral border of the vertebral body for C3-C6 ranged from 1.8 to 2.2 mm. The average distance between the anterior borders of the vertebral artery foramina and the anterior border of the vertebral body gradually decreased from C3 (8.4 +/- 1.4 mm) to C6 (7.0 +/- 1.6 mm). This study suggested that the lateral border of the vertebral body may be a reliable landmark during anterior cervical decompression. The vertebral artery foramen should be free of violation if vertebrectomy or subtotal vertebrectomy is performed medial to the lateral border of the vertebral body.

The “open” exit foramen: A new sign of unilateral interfacetal dislocation or subluxation in the lower cervical spine

The purpose of this study was to describe the “open” exit foramen as a new sign associated with unilateral interfacetal dislocation or subluxation (UID/S) of the cervical spine. Three blinded observers evaluated 20 randomly ordered axial imaging examinations (9 with UID/S and 11 traumatized control patients) assessing for presence or absence of the open exit foramen sign at the level of injury. The clinical observations were then quantified by measuring the width of the involved cervical exit foramen at the level of injury on axial computed tomography or magnetic resonance imaging in nine patients with UID/S. These measurements were also compared to the width of contralateral uninvolved exit foramen at the level of UID/S and to ipsi- and contralateral exit foramen measurements of 20 control patients with acute cervical spine injuries but no UID/S. Measurements were analyzed using Student’st-test. Calculated sensitivity and specificity for blinded reviewer detection of the open exit foramen sign in cases of UID/S vs. traumatized controls were 78% and 79%, respectively. Quantitative measurements indicate the involved exit foramen was enlarged by an average of 3.9 mm compared to the contralateral exit foramen at the levels of UID/S, whereas controls demonstrated only 0.9 mm of foraminal asymmetry (P<0.01). In cases of UID/S, asymmetric widening of the exit foramen occurs in the axial plane, resulting in the open exit foramen sign. Blinded review confirms that this sign is clinically helpful in identifying the level and side of UID/S on axial imaging studies.

Replantation of 400 avulsed permanent incisors. 2. Factors related to pulpal healing.

Four hundred avulsed and replanted permanent teeth were examined for pulpal healing. In 110 teeth, the apical foramen was either open or half-open. In 16 teeth, the pulps were extirpated prophylactically. Thus, pulpal revascularization was considered possible in 94 teeth. Revascularization occurred in 32 teeth (34%). Pulp necrosis could usually be demonstrated after 3 weeks. Positive pulpal sensibility and radiographis signs of pulp canal obliteration were usually observed after 6 months. The effect of various clinical factors was examined, such as sex, age, type of tooth replanted, stage of root formation, type and length of extra-alveolar storage, clinical contamination of the root surface, type of cleansing procedure of the root surface, type and length of splinting and the use of antibiotics. Finally, the width of the apical foramen and the length of the root canal were measured on radiographs taken at the time of injury. A multivariate statistical analysis revealed that pulpal revascularization was more frequent in teeth with shorter distances from the apical foramen to the pulp horns. Furthermore, that wet storage (saliva and/or saline) for more than 5 min decreased the chance of pulpal revascularization; whereas dry extraalveolar storage had a monotonous effect on pulpal revascularization, i.e. decreasing chance of revasculatization with increasing length of the extraalveolar dry storage. Based on these findings, immediate replantation after brief cleansing in either tap water or saline is recommended.

Modern treatment of avulsed teeth by emergency physicians

New research has shown that the incidence of success of replanted avulsed teeth can be greatly increased by differentially diagnosing and treating them according to the length of extraoral time and the physiological width of the apical foramen. A specific treatment regimen has been presented that will give the physician the information necessary to maximize the success of replanted avulsed teeth that may be seen.

Concerning the inferior portion of the spinal radiotherapy field for malignancies that disseminate via the cerebrospinal fluid

Purpose : Many radiotherapists widen the inferior aspect of the craniospinal irradiation field to encompass the sacroiliac joints and “cover the sacral nerve roots.” This is commonly referred to as a “spade” field. Other therapists, however, reject the notion of widening the bottom of the field—feeling that straight field borders are adequate. We have evaluated this controversy by an anatomical study. Methods and Materials : Twenty-five skeletons were measured to ascertain the distance between the outermost portions of the posterior pedicles of L3, L4, and L5; the distance between the outermost portions of the intervertebral foramina between L3–L4, L4–5, and L5–Sl through which the spinal nerves pass; and the width of the most lateral portions of the posterior and anterior foramina of S1 and S2 through which the sacral spinal nerves would pass. Twenty-two cranial spinal irradiation simulator films of patients with medulloblastoma were used to measure the distance between the outermost portions of the posterior pedicles of L3, L4, and L5 and the foramina of S1 and S2. These measurements were then corrected for film magnification. Results : Skeleton measurements showed that the mean width between the outer portions of the posterior pedicles of L3 and 4.1 cm, for L4 it was 4.4 cm, and for L5 it was 5.1 cm. Measurements of the mean maximum width of the intervertebral foramen for nerve root exit at the bottom of L3 was 4.1 cm, for L4 4.4 cm, and for L5 4.7 cm. The mean distance between the outermost portions of the intervertebral foramen for nerve root exit at the front of S1 was 5.9 cm while it was 5.0 cm for the back of St. The mean distance between the outermost portions of the anterior foramen of S2 was 5.7 cm and 4.8 cm for the back. Measurements from the 22 simulation films show that the mean maximum width between the outer portion of the posterior pedicles of L3 was 3.3 cm, for L4 3.5 cm, and for L5 3.8 cm. The mean maximum width of the intervertebral foramen for nerve root exit at the bottom of S1 was 4.4 cm and 4.5 cm for S2. Conclusions : While the caudal end of the craniospinal field needs to be widened by 1.2 to 1.8 cm to encompass the increase in distance between nerve root exits as one moves inferiorly down the spine, coverage of the sacroiliac joints is not necessary.

The influence of the major and minor foramen diameters on apical electronic probe measurements

There have been conflicting reports on the accuracy of electronic devices used for determining working length. The influence of the major and minor diameters on electronic probe measurements were evaluated to ascertain whether anatomical features of the apical portion of the canal might be responsible for these discrepancies. Forty-seven nonrestorable teeth selected from 22 patients were studied. Conventional access was made. A Kerr file was placed to a position 0.5 mm from the major foramen as registered by the Neosono-D apex locator. The electronic probe length was then measured. After the tooth was extracted, the file was fixed with autopolymerizing composite in the canal. A Buehler Isomet lapadary saw was used to prepare specimens to a thickness of 500 microns. A Bioquant II Image Analysis System was used to measure and record distances. It was found that as the width of the major foramen increased, the discrepancy between the electronic probe tip length induction and the actual position of the major foramen increased.

Pulp revascularization in reimplanted immature monkey incisors – predictability and the effect of antibiotic systemic prophylaxis

In 32 monkeys 105 immature maxillary incisors were extracted and reimplanted either immediately or after 30 or 60 min wet or dry storage. Of the monkeys, 17 (group I) did not receive and 15 (group II) received prophylactic treatment with 4 mg/kg doxycycline before extraction and 2 mg/kg for 5 d after reimplantation. The observation time varied from 6 to 8 weeks. After being histologically processed, the material was evaluated with respect to the amount of vital tissue and presence of micro-organisms in the pulpal lumen. A comparison revealed no difference in the results between the groups. The results were therefore pooled and statistically analysed with respect to the significance of apical foramen width, extra-alveolar time, wet or dry storage and presence of micro-organisms in the pulpal lumen for the occurrence of complete pulp revascularization (CPR). The overall frequency of CPR was 18%. Log-linear analyses (SAS, 1985) of the material as a whole or of separate parameters consistently revealed a relationship between presence of micro-organisms and absence of CPR (P = 0.0001). A higher frequency of CPR and a lower frequency of micro-organisms (P = 0.05) was found only for the group of immediately reimplanted teeth. The presence of micro-organisms could be explained for 61 teeth. In 27 of these, blood clots containing bacteria in the apical portion of pulpal lumen indicated contamination during the extra-alveolar time, while in 34, the micro-organisms originated from plaque covered mechanical damage in the cervical part of the root surface.

Nongeographic Morphologic Variation in the Mexican Vole (Microtus mexicanus)

Nongeographic Morphologic Variation in the Mexican Vole (Microtus mexicanus)

Systematics of New England Microtus, with Emphasis on Microtus breweri

Systematic relationships of New England Microtus were examined using discriminant analysis of cranial and dental measurements on eight samples of M. pennsylvanicus, M. breweri , and M. chrotorrhinus . In one analysis, specimens of M. breweri (Muskeget Island, Massachusetts) and M. pennsylvanicus (Cape Cod, Massachusetts) were more similar to each other than the latter was to other M. pennsylvanicus samples. Most of this similarity derived from the width of the palatine foramen. M. breweri and M. pennsylvanicus of Cape Cod shared a palatine-foramen shape that differed from all other M. pennsylvanicus samples and from M. chrotorrhinus . In analyses excluding the palatine foramina, M. pennsylvanicus from Cape Cod were more similar to other M. pennsylvanicus samples than to M. breweri . All specimens of M. breweri were classified correctly by discriminant functions that separated them from mainland M. pennsylvanicus . Similar results were obtained using dental variables alone. Discrete dental characters of M. breweri also showed striking differences from those of M. pennsylvanicus . The degree of separation between M. breweri and M. pennsylvanicus was comparable to that between M. chrotorrhinus and M. pennsylvanicus . This study supports the specific status of M. breweri .

Rate and predictability of pulp revascularization in therapeutically reimplanted permanent incisors.

Abstract The aim of the present investigation was to study the frequency of pulp revascularization in therapeutically reimplanted incisors as well; is its relationship with the following factors: width of apical foramen, duration of extra‐alveolar lime, storage conditions and postoperative administration of antibiotics. Out of 72 immature teeth (width of apical foramen 1.1–5.0 mm) the pulp was revascularized in 13 (18%), while in 88 mature teeth (width of apical foramen 1.0 mm or less) no revascularization occurred. Among parameters tested statistically in immature teeth, a significantly increased frequency of revascularization (p &lt; 0.05) was only found in teeth reimplanted within 45 minutes after avulsion, when compared with teeth reimplanted after a longer extra‐alveolar time, and in mandibular incisors when compared with maxillary incisors (p &lt; 0.01). All teeth in which revascularization did not occur exhibited a periapical radiolucency and/or external inflammatory root resorption.

Histologic and clinical assessment of long-term pulpal-periodontal therapy

A 20-year follow-up of cases published in 1959 involving the treatment of pulpal-periodontal disease suggests the following: 1. 1. The periodontal results have been stable except for one case of root resorption and one case in which there was gingival recession with no pocket formation. 2. 2. The histologic evidence in the resorbed case would suggest that repair had occurred with the formation of new bone, ligament, and cementum. 3. 3. There was also evidence from the histologic sections that the inflammatory response was localized to the region of the apical foramen. 4. 4. There was secondary osteocementum on the dentin surface inside the root canal which had narrowed the width of the apical foramen. 5. 5. There was x-ray and histologic evidence that previously well-condensed gutta-percha had been resorbed during a 20-year period in all of the four treated root canals.

Additional Observations on the Recognition Features of the Culex tarsalis Larva and Pupa (Culicidae: Diptera)

instar stage, comparing these features with those of the younger larval stages and illustrating the chaetotaxy of the larval and pupal abdomen. The illustration of the pupa may be of aid for future taxonomic studies and the preparation of keys. Methods The larvae and pupae were reared in the laboratory from eggs deposited by female mosquitoes collected in Kansas. The specimens, killed by heating slowly, were preserved in 70% alcohol. Pupal skins, temporarily and permanently mounted larvae and pupae were observed for this study. All measurements were made on specimens cleared in creosote and mounted in Canada balsam. Observations on the Larva Growth of the larva was accompanied by greater size and complexity of nearly all features studied and these features occupied closely a similar position in each subsequent instar. Particularly obvious differences noted among the instars studied were the absence of ventral hair tufts on the anal segment of the first instar and completion of the dorsal plate of the fourth instar. These characteristics were observed only in the instar mentioned. The second and third instars were each separated by relative comparison of certain features. The width of the occipital foramen, compared with the width of the head, decreased proportionately with each larval molt and the difference was especially evident between the second