Lateral Oblique Radiographs Research Articles

Correlation between miniscrew stability and bone mineral density in orthodontic patients

The aims of this study were to correlate the clinical and radiographic stability of titanium miniscrews when used as orthodontic anchorage for maxillary canine retraction and to assess bone quality. Thirty titanium miniscrews were placed in 15 consecutive patients (8 male, 7 female; age range, 12 years 5 months-32 years 11 months) as orthodontic anchorage. Orthodontic loads were applied immediately after miniscrew placement (T1) with a nickel-titanium closing coil spring. The initial estimated load was 200 g. The bone quality in each region of interest was determined by multi-slice computed tomography. Bone mineral density (BMD) values ranged from 167 HU to 660.80 HU (mean, 420.63 HU). The specific regions had a mean close to the maximum value of a previously established scale for the posterior region of the maxilla (0-500 HU). The paired t test showed a statistically significant difference (P = 0.450) when the means of the differences between the right and left sides were compared. Twelve of the 15 subjects had significantly greater maxillary BMD on the right side. Linear regression also showed a low correlation between the 2 sides (P = 0.097). Clinically, the success index was 100%. Although 2 miniscrews were removed from 1 patient because of severe gingival inflammation with purulent secretion, none of the 28 remaining miniscrews showed any mobility after 90 days (T2). Comparisons of the means at T1 and T2 showed no statistically significant differences in these distances: between nasion and the miniscrew head, between orbitale and the miniscrew head, and between nasion and orbitale, assessed through cephalometric tracings made on lateral oblique radiographs (45 degrees ), pointing to the stability of the 28 miniscrews during the 90-day observation period. BMD values of all subjects were within the normal range of an established scale, and even close to maximum values. The regions between the maxillary second premolars and first molars, and mesial to the maxillary second premolars, are safe as far as bone quality is concerned for miniscrew placement during the first 90 days of canine distalization. A good surgical technique and appropriate planning for miniscrew placement, inflammation control, and adequate oral hygiene are fundamental to the success of this new anchorage system during maxillary canine distalization.

Optimal parameters for lateral oblique radiographs of rat mandibles

To establish optimal exposure parameters for lateral oblique radiographs of rat mandibles using an intraoral X-ray machine. A positioning apparatus, previously tested for its reproducibility, was used to obtain radiographs of four heads of formaldehyde-preserved Wistar rats. Radiographs were exposed at 50 kV and 8 mA using four size 2 films (Insight, Ektaspeed Plus, Ultraspeed and D-Speed; Eastman Kodak Co., Rochester, NY), two focal distances (30 cm and 60 cm) and seven exposure times (0.6 s, 0.7 s, 0.8 s, 1.0 s, 1.5 s, 2.0 s and 2.5 s). The radiographs were evaluated by two examiners and scored for image quality: 1, very poor; 2, poor; 3, fair; 4, good; and 5, excellent. The evaluations were repeated at 30 days. Intraobserver reproducibility was substantial (kappa = 0.798 and 0.667). Also, the two examiners showed substantial agreement (kappa = 0.726). There was a significant difference (alpha = 1%) between the scores for the films under study. At a 30 cm distance, E-speed films had mean scores of 4 and 5 at 0.8 s and 1 s exposure times, and D-speed films, at 1.5 s, 2 s and 2.5 s exposure times. At a 60 cm distance, the best results were found for E-speed films at 2.0 s and 2.5 s exposure times. The films under study did not show any significant difference in the quality of rat mandible images as long as exposure times were adequate to their sensitivity and focal distance.

Morphological aspects of tympanic bulla after lateral osteotomy in cats

To evaluate tympanic bulla healing after experimental lateral osteotomy in cats. Twenty adult cats were submitted to unilateral lateral bulla osteotomy and divided into two groups: cats of B1 group (n=10) were euthanized at 8 weeks and cats of B2 group (n=10), at 16 weeks postoperative. Oblique lateral radiographs taken immediately postoperative showed interruption in the contour of the external acoustic meatus of the operated bullae in all cats of both groups (McNemar test: p=0.0010*). This feature was still observed in the radiographs taken after 8 and 16 weeks postoperative (McNemar test: B1 p=0.0020*; B2 p=0.0312*). Macroscopic examination showed that the operated bullae were similar to the normal ones, with preservation of the tympanic cavity. Connective tissue at the osteotomy site was significantly found in the operated bullae in both groups (McNemar test: B1 p=0.0020*; B2 p=0.0010*). The length of connective tissue at the osteotomy site was measured by histomorphometry. There was no statistically significant difference between the values of B1 group and B2 group (Mann-Whitney test: p=0.0524). Experimental lateral osteotomy did not alter significantly the tympanic bulla conformation and complete regeneration of the tympanic bulla frequently did not occur before 16 weeks of postoperative period.

Oblique chest views as a routine part of skeletal surveys performed for possible physical abuse—Is this practice worthwhile?

Objective To evaluate the utility of oblique chest views in the diagnosis of rib fractures when used as a routine part of the skeletal survey performed for possible physical abuse. Methods Oblique chest views have been part of the routine skeletal survey protocol at Primary Children's Medical Center since October 2002. Dictated radiology reports since that time were reviewed, and all cases with rib fractures documented were chosen for study. For each chosen case two pediatric radiologists identified and recorded rib fractures using only the PA and lateral chest radiographs (standard two-view chest series) from the skeletal survey for each case. In a separate session they identified and recorded rib fractures using the PA, lateral, right oblique, and left oblique radiographs (four-view chest series) from the skeletal survey for each case. The results were compared. Results Twenty-two cases with rib fractures were identified. Interpretation of the four-view chest series was different than interpretation of the two-view chest series in 12 of the 22 cases (54%). Overall, the four-view chest series differed significantly in the number of rib fractures diagnosed compared with the two-view chest series ( p = .02, Wilcoxon matched-pairs signed-rank test) adding 19 rib fractures and excluding 6 rib fractures. Conclusions The results indicate that use of the four-view chest series adds information to that obtained from the two-view chest series and increases the accuracy of diagnosing rib fractures in cases of possible physical abuse. Addition of oblique chest views to the routine protocol for skeletal surveys performed for possible physical abuse is recommended.

A longitudinal study of normal asymmetric mandibular growth and its relationship to skeletal maturation

Our aims in this investigation were to assess asymmetric mandibular growth relative to skeletal maturation and to determine whether asymmetric growth occurs during a period of high growth velocity. We evaluated lateral oblique and hand-wrist radiographs of 30 male and 30 female Class I participants in the Burlington Growth Study who were assessed at 3 time periods with the skeletal maturation index (SMI). The body, the ramus, the effective length, and the gonial angle on each side of the mandible were measured. Asymmetry between the right and left sides was analyzed with the SMI and for sex dependency. The left ramus was consistently longer than the right in all evaluation periods (P <.05). The right body was consistently longer than the left in all evaluation periods (P <.05). The effective length showed no asymmetry until the last maturation group, when the right side was longer (P <.05). The gonial angle had no significant differences. Tests to determine differences between the sexes showed no significance in asymmetry, but the body, the ramus, and the effective length were longer in males than in females (P <.05). Asymmetry does not occur or increase during any specific growth period.

Assessment of middle ear disease in the dog: a comparison of diagnostic imaging modalities

To compare radiography and ultrasound for the assessment of the tympanic bulla against computed tomography results. Thirty-one dogs had dorsoventral, left and right lateral oblique and rostrocaudal open mouth radiographs compared with ultrasound images and computed tomography scans of the tympanic bullae. Radiography was superior to ultrasonography for the evaluation of the middle ear. However, computed tomography assessment was best predicted by a combination of radiographic and ultrasonographic findings. A combination of radiography and ultrasound can provide a more accurate assessment of the bulla than either of them alone. Ultrasound may have a role in the evaluation of middle ear disease in the dog. Results are operator dependent and not reproducible with current recording techniques.

Internal Oblique Radiographs for Diagnosis of Nondisplaced or Minimally Displaced Lateral Condylar Fractures of the Humerus in Children

Several radiographic criteria based on only standard anteroposterior and lateral radiographs have been suggested for predicting the stability of lateral condylar fractures of the humerus in children. Despite adherence to these guidelines, further displacement often occurs after the initial diagnosis and stability assessment. The purpose of this study was to define the usefulness of an internal oblique radiograph in the assessment of these fractures. We prospectively studied fifty-four lateral humeral condylar fractures in fifty-four children seen between March 2002 and December 2004 to determine the efficacy of internal oblique radiographs in gauging the amount of displacement and the fracture pattern. Plain anteroposterior, lateral, internal oblique, and external oblique radiographs were initially made for all fifty-four patients, and three-dimensional computed tomography scans were performed for seven patients. A large percentage (70%) of the fractures were seen to have different amounts of displacement on the anteroposterior and internal oblique radiographs, and a large percentage (75%) were seen to have different fracture patterns, according to the criteria suggested by Finnbogason et al., on the two views. The internal oblique radiograph was more accurate for demonstrating the fracture gap (thirty cases were seen to have more displacement on that view) and for demonstrating the fracture pattern (twenty cases were seen to have more instability on the internal oblique view). We also confirmed the direction of the fracture line and the location of the fragment more accurately with three-dimensional computed tomography. It is not optimal to evaluate the amount of displacement and the stability of a lateral condylar fracture of the humerus in children on the basis of just anteroposterior and lateral elbow radiographs. Classifications should be based on the greatest displacement seen on at least three radiographic views, especially the internal oblique view.

Changes in condylar mobility and radiographic alterations after treatment in patients with non-reducing disc displacementof the temporomandibular joint

The purpose of this study was to examine changes in condylar mobility and morphological changes in the affected condyles after treatment in patients with non-reducing disc displacement of the temporomandibular joint (TMJ). Changes in condylar mobility and morphological changes of the condyle were examined radiographically in 55 patients who were diagnosed as having non-reducing disc displacement of the unilateral TMJ and had received pumping with injection of sodium hyaluronate. In all patients, standardized lateral oblique transcranial radiographs and panoramic jaw tomograms were taken both at initial visit and at 12 months or more follow-up (mean 28.1 months after treatment; range 12-104 months). 42 joints in 21 persons with no current or previous TMJ symptoms served as a control. Clinical signs and symptoms improved after treatment in the patients. Condylar mobility significantly increased after treatment in patients (P<0.001), although it did not reach levels of the control group. Frequency of radiographic changes of the condyle significantly increased after treatment (P<0.005). In most of the patients, no or only mild changes were observed. Frequency of changes of the condyle in patients at follow-up was significantly greater than that in controls (P<0.001). In the patients, condylar mobility increased in the subsequent course after treatment. However, bony changes of the condyle appeared more frequently. Long term-follow-up after treatment on bony changes of the condyle seems to be necessary in patients with non-reducing disc displacement of the TMJ.

Location of the mandibular foramen-Radiographic study

A comparison between the location of mandibular foramen on ten dry mandibles has been used in this study with its location on the two extraoral radiographic projections taken for each dry mandible. First projection with the use of panoramic radiograph and the second projection have been taken by lateral oblique jaw projection. The results are shown no significant difference between the measurements are taken from both radiographs. But still the lateral oblique jaw radiograph is more resoluted and accurate in the localization of the mandibular foramen.

Temporomandibular joint morphology in Cavalier King Charles Spaniels.

Temporomandibular joint dysplasia has been reported in several breeds of dog. Three Cavalier King Charles Spaniel (CKCS) skulls were examined and radiographed during the course of a separate study and all demonstrated changes consistent with bilateral temporomandibular joint dysplasia. Subsequently, skull radiographs from all CKCS dogs examined at the University of Glasgow Veterinary School between 1991 and 2001 were reviewed (n = 26). Only two of these dogs were radiographed specifically for investigation of the temporomandibular joint, although varying degrees of dysplasia were identified in all dogs where the joints were adequately visualized (n = 20). The head of four CKCS cadavers was also radiographed, and similar changes were found. This finding suggests that temporomandibular joint dysplasia is a widespread asymptomatic condition in the CKCS and should be regarded as a normal morphologic variation rather than a pathologic anomaly. Subtle changes are best seen on lateral oblique radiographs, although marked changes are also visible on dorsoventral views. The rotational angle or angle of articulation of each of the dysplastic mandibular condyles was measured and was related to the severity of the dysplastic changes. However, there was overlap between the values calculated for these abnormal joints and normal ones in other breeds, suggesting this measurement was of limited significance and the shape of the components of the temporomandibular joint are more relevant when assessing this joint for the presence of dysplastic changes.

The genu of the submandibular duct--is the angle significant in salivary gland disease?

To investigate whether the angle of the genu of the submandibular duct is a significant contributory factor in the development of salivary calculi or sialoadenitis. A preliminary test with a phantom was performed, taking oblique lateral views with different vertical and horizontal beam angulations to assess the effect on the genu angle. The phantom comprised a dried mandible and a piece of wire bent to simulate the submandibular duct. There were no differences in the measured angle of the bend in the wire within the range of beam angulations used in the clinical study. One hundred and two sialographs were analysed from three separate groups of patients, normal controls (n=18), proven salivary calculi (n=61) and those with sialoadenitis (n=23). The oblique lateral radiographs were digitised and imported into the Denoptix digital system, and the angle measured using the VixWin 2000 software. Differences in angle between groups were investigated using analysis of variance. The mean angle of the genu was 103 degrees (range 41 degrees-147 degrees) in the control group, 108 degrees (range 46 degrees-178 degrees) salivary calculi group, and 91 degrees (range 24 degrees-155 degrees) in sialoadenitis patients. There were no statistical differences in the angle between the groups. There is a wide variation in the angle of the genu of the submandibular duct (24 degrees -178 degrees ). This angle does not appear to be associated with either sialolithiasis or sialoadenitis.

The oblique radiographic technique for bone height measurements on edentulous mandibles: A preclinical study and an introduction to the clinical use

Objective. The aim of this study was to quantify the effect of mandibular angulation, position, and shape of the edentulous mandible on the distortion of its image on lateral oblique radiographs in a preclinical study. Suggestions for the clinical use of this technique are made. Study design. Five edentulous dry mandibles were used, varying in size from small to wide and equipped with metal bars in and on top of the mandible. The mandibles were radiographed at 9 different positions by tilting the mandible around the intercondylar axis and by using the oblique projection technique in a cephalostat. Results. The length of the images of the metal bars varied significantly when we tilted the mandibles from 20 degrees to –20 degrees. As a result of the effects of magnification and distortion, the image size varied from between 0.96% and 1.06% of the real size. Neither the size of the mandible nor the position of the bars was related to the degree of magnification. Conclusion. The oblique projection technique has limited geometric errors in depicting the edentulous mandible. For evaluative bone height measurements in patients with extremely resorbed mandibles treated with dental implants, it is a promising technique if the patient (specifically the mandible) can be positioned reproducibly in the apparatus. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;89:522-9)

The effect of surgically induced anterior disc displacement of the temporomandibular joint on the midface and cranial base.

The purpose of this study is to investigate the effect of unilateral TMJ disc displacement on the midface and cranial base. Thirteen 10-week-old rabbits, eight controls and five experimental were included in this study. The five experimental rabbits had surgically created unilateral disc displacement. Animals were sacrificed at 22 weeks and frontal, occlusal, and lateral oblique radiographs were made of the skulls. The occlusal radiograph demonstrated that the glenoid fossa on the experimental side was located more anterior. The oblique radiograph demonstrated the root of the zygomatic arch the experimental side was inferior. The anterior aspect of the fossa was more inferior on the frontal radiograph. A previous study suggested a shortening in the ramal height. This study suggests an alteration of the cranial articular fossa. Thus, it is suggested that disc displacement is capable of producing asymmetry in the developing mandible and cranial base.

Orientation of lumbar pars defects

Lateral oblique radiographs are considered important for the identification of spondylolytic lesions, but these projections will give a clear view only when the radiological beam is in the plane of the defect. We studied the variation in orientation of spondylolytic lesions on CT scans of 34 patients with 69 defects. There was a wide variation of angle: only 32% of defects were orientated within 15° of the 45° lateral oblique plane. Lateral oblique radiographs should not be considered as the definitive investigation for spondylolysis. We suggest that CT scans with reverse gantry angle are now more appropriate than oblique radiography for the assessment of spondylolysis. Variation in the angle of the defect may also need consideration when direct repair is being planned.

Orientation of lumbar pars defects: implications for radiological detection and surgical management.

Lateral oblique radiographs are considered important for the identification of spondylolytic lesions, but these projections will give a clear view only when the radiological beam is in the plane of the defect. We studied the variation in orientation of spondylolytic lesions on CT scans of 34 patients with 69 defects. There was a wide variation of angle: only 32% of defects were orientated within 15 degrees of the 45 degrees lateral oblique plane. Lateral oblique radiographs should not be considered as the definitive investigation for spondylolysis. We suggest that CT scans with reverse gantry angle are now more appropriate than oblique radiography for the assessment of spondylolysis. Variation in the angle of the defect may also need consideration when direct repair is being planned.

Tooth eruption through autogenous and xenogenous bone transplants: a histological and radiographic evaluation in beagle dogs

The effect of implanting autogenous and xenogenous (Bio-Oss) bone transplants into metabolically active sites within beagle dog mandibles during permanent premolar tooth eruption was examined. Ten 14-week-old beagles were used. Before commencing the radiographic experiments, metal bone markers were placed in the caudal margin of the mandible at the age of 10 weeks. The deciduous first and third molar teeth were extracted and their sockets over the permanent second and fourth premolars were implanted with autogenous particulate enchondral iliac crest bone, autogenous particulate membraneous mandibular body bone, xenogenous bovine anorganic bone mineral spongiosa granules (1-2mm3) (Bio-Oss, Geistlich Pharma, Switzerland) of left empty. The third premolar served as control site. Standardized oblique lateral radiographs were taken once a week. A number of coordinates of defined points and structures were determined by means of a coordinate digitizing system. Animals were killed 4, 10 and 16 weeks after bone transplantation for histological examination of the transplantation sites. All premolars showed no delay in eruption or disruption of crown and root development. On histology, the Bio-Oss particles were not resorbed or integrated in the alveolar bone but were pushed forward into the gingiva. We have demonstrated that there is on difference in the eruption curve of the permanent premolars in the four groups (ANOVA P > 0.5) and that bone transplantation has no inhibitory effect on eruption (ANOVA P > 0.3) and crown development of the underlying permanent premolar but that Bio-Oss does not have the same resorbable or integrating capability as autogenous bone grafts.

Radiographic evaluation of mandibular augmentation with prefabricated hydroxylapatite/fibrin glue implants

Purpose: This study radiographically evaluated the stability of mandibular height during a 2-year follow-up after augmentation with prefabricated hydroxylapatite/fibrin glue (HA/FG) implants. Patients and Methods: Standardized, lateral oblique cephalometric radiographs were made of 22 patients 6, 12, and 24 months postoperatively and analyzed with a newly developed, computerized image analysis technique. Results: The average height of the HA/FG implants after augmentation was 9.45 mm. Average loss of total height of the augmented mandibles was 2.31 mm after 6 months, 2.90 mm after 12 months, and 3.93 mm after 24 months. Reduction of HA/FG implant height alone was 0.62 mm after 6 months, 1.24 mm after 12 months, and 2.03 mm after 24 months. Reduction occurred mainly during the first 6-month evaluation period and was probably primarily caused by adaptation of the implant to the surface of the mandible. An inferior compression of the implant or resorption of the alveolar crest and underlying basilar bone are possible reasons for loss of total mandibular height. Conclusion: The results indicate that prefabricated HA/FG implants used for augmentation of edentulous mandibles show little reduction in height, but are not completely stable during a 2-year evaluation period.

Osteomyelitis of the calcaneus in children.

Eleven cases of calcaneal osteomyelitis in children are reported. Seven were hematogenous cases, and the remaining four were related to puncture wounds. The clinical presentation was less dramatic than that seen in typical long bone osteomyelitis. Laboratory findings were also less striking. A mixture of organisms was isolated from patients in the hematogenous group. In contrast, all puncture-related cases had cultures positive for Pseudomonas aeruginosa. Plain radiographic findings were noted at the time of presentation in 63%. Those findings were characteristically different in hematogenous and puncture-related cases. Oblique lateral radiographs can be important for diagnosis in puncture-related cases. Radionuclide bone scanning was an important diagnostic test in the absence of plain radiographic changes and in the very young patient. Surgery was performed in 82% of the cases. There were no recurrences or chronic infections. Two complications occurred in one patient, including residual scar sensitivity and early fusion of the calcaneal apophysis.

Osteomyelitis of the Calcaneus in Children

Summary Eleven cases of calcaneal osteomyelitis in children are reported. Seven were hematogenous cases, and the remaining four were related to puncture wounds. The clinical presentation was less dramatic than that seen in typical long bone osteomyelitis. Laboratory findings were also less striking. A mixture of organisms was isolated from patients in the hematogenous group. In contrast, all puncture-related cases had cultures positive for Pseudomonas aeruginosa. Plain radiographic findings were noted at the time of presentation in 63%. Those findings were characteristically different in hematogenous and puncture-related cases. Oblique lateral radiographs can be important for diagnosis in puncture-related cases. Radionuclide bone scanning was an important diagnostic test in the absence of plain radiographic changes and in the very young patient. Surgery was performed in 82% of the cases. There were no recurrences or chronic infections. Two complications occurred in one patient, including residual scar sensitivity and early fusion of the calcaneal apophysis.

Intraarticular placement of Kurosaka interference screws

Interference screws are commonly used for graft fixation in arthroscopically assisted anterior cruciate ligament reconstruction. A potential complication with the use of interference screws is intraarticular violation of the screw tip. Postoperative radiographs often lend confusion to the exact screw location. We devised an anatomic-radiologic study to evaluate factors (including local anatomy, radiographic projection, and radiographic technique) in order to clarify these misunderstandings. We found that radiographic projection, obliquity, and the local bony anatomy contribute to erroneous radiographic interpretation. The most significant finding was that the lateral radiograph and cephalad oblique lateral radiographs frequently suggest screw tip violation of the joint when in fact it has not occurred. Caudal oblique lateral radiographs fail to raise concern even when joint violation by the screw tip has occurred. Good quality true anteroposterior radiographs appear most consistent in determining true screw tip location.