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Biomedical subjects

A Isberg

Publications and source records attributed to A Isberg.

At least 55 records · Page 3Linked to original sources
PubMed1990

A cephalometric analysis of patients with coronoid process enlargement and locking.

Two patient groups with radiographically verified coronoid process locking were cephalometrically examined. In eight patients the locking was of congenital origin, and in eight patients the locking had developed as a result of internal derangement of the temporomandibular joint. When compared with that in a control group, the height of the coronoid process was statistically significantly greater in both patient groups, but there was no difference on condylar height between any of the groups. Neither were there any differences between groups regarding the upper face height, which, if present, could have been expected to contribute to the development of coronoid process locking. In the group with congenital enlargement, the mandibular configuration was strikingly square-shaped, which was expressed by a statistically significantly smaller gonion angle than was present in the other two groups. The finding was interpreted as a growth effect due to the mandibular locking.

Adult↗
PubMed1989

Mobility of the upper esophageal sphincter in relation to the cervical spine: a morphologic study.

If the posterior part of the upper esophageal sphincter (UES) were to lag behind due to the presence of dense tissue strands between the sphincter and the prevertebral ligament, as suggested in the literature, it would be impossible to use the larynx as a radiographic indicator of the location of the UES at intraluminal pressure measurements. The goal of this investigation was to study UES behavior during induced movements in autopsy specimens and to search for dense fibrous strands between the UES and the prevertebral fascia. Histologic studies of frozen sections and paraffin sections showed a loose fatty tissue in the prevertebral space. There were no dense connective tissue strands. Autopsy specimens were used in experiments mimicking the laryngeal/UES elevation during swallowing. The results of this study indicate that the larynx and the UES move as one entity. When one is attempting to register the UES movement during swallowing, the laryngeal skeleton can therefore serve as a radiographic indicator of the UES movements.

Adult↗
PubMed1989

Subjective symptoms in patients with temporomandibular joint disk displacement versus patients with myogenic craniomandibular disorders.

Signs and symptoms in the masticatory system can be caused by several specified diseases leading to diagnostic problems. This investigation compared patients with temporomandibular joint disk displacement and patients with complaint of myogenic craniomandibular disorders. In association with the onset of the patient's problem, a physical event was found in half the number of patients with permanent disk displacement, compared with only 27% in the myogenic craniomandibular disorders group. Patients with permanent disk displacement reported more pain in the temporomandibular joint ear and jaw region in association with jaw function whereas patients with myogenic craniomandibular disorders reported more bruxism and dental discomfort.

Adolescent↗
PubMed1989

The location of the upper oesophageal sphincter and its behaviour during bolus propagation--a simultaneous cineradiographic and manometric investigation.

By means of simultaneous cineradiographic and manometric examinations using closely positioned microtransducers the maximal pressure of the upper oesophageal sphincter was found at a level 20 mm below the plane of the vocal folds and 6 mm above the level of the cricoid arch. The sum of these 2 distances is in accordance with the distance between the vocal fold level and the lower border of the cricoid arch given in the literature. This implies that the high pressure zone of the upper oesophageal sphincter corresponds to the pars fundiformis of the cricopharyngeus muscle. The lower part of the inferior pharyngeal constrictor and the upper circular muscle fibres of the oesophagus contribute to the sphincter. When the bolus approached the sphincter, the pressure decreased and during bolus passage the pressure was below or well below half of the resting pressure. The pressure profile disclosed no signs of muscular dyscoordination or discontinuity of the upper oesophageal sphincter.

Adult↗
PubMed1989

Absorbed doses and energy imparted from radiographic examination of velopharyngeal function during speech.

Absorbed doses of radiation were measured by thermoluminescent dosimeters (TLDs) using a skull phantom during simulated cinefluorographic and videofluorographic examination of velopharyngeal function in frontal and lateral projections. Dosages to the thyroid gland, the parotid gland, the pituitary gland, and ocular lens were measured. Radiation dosage was found to be approximately 10 times less for videofluoroscopy when compared with that of cinefluoroscopy. In addition, precautionary measures were found to reduce further the exposure of radiation-sensitive tissues. Head fixation and shielding resulted in dose reduction for both video- and cinefluoroscopy. Pulsing exposure for cinefluoroscopy also reduced the dosage.

Absorption↗
PubMed1988

Loss of directional orientation control of lower jaw movements in persons with internal derangement of the temporomandibular joint.

Lateral mandibular movements were performed on command by 50 patients with TMJ disk displacement associated with severe pain. In 22 patients the displacement was reversible, and in 28 patients it was permanent. An additional 50 patients with disorders of the masticatory system other than disk displacement were examined, as well as a group of 50 subjects without any signs or symptoms involving the masticatory system. The results showed that 22 patients (4 with reversible and 18 with permanent disk displacement) failed to move the mandible without tooth contact toward a predetermined direction and, instead, moved it in the opposite direction. The persons themselves were convinced that the direction of movement was correct. If finger pressure was applied to the joint area on the affected side, 25% of the patients with loss of directional control were able to move correctly. A normalization of the directional control was attained in 20% of the cases if lateral movements were performed with light tooth contact. All the patients with disorders of the masticatory system other than anterior disk displacement demonstrated a correct lateral mandibular movement pattern. In the control group, 2% demonstrated incapability of directional control of lateral jaw movements. The results indicate that loss of directional control of the lower jaw is associated with disk displacement.

Cartilage, Articular↗
PubMed1988

Influence of tonsils on velopharyngeal movements in children with craniofacial anomalies and hypernasality.

Velopharyngeal activity and tongue and tonsil movements were examined cineradiographically in the connected speech of 40 hypernasal children with craniofacial disorders--20 with small tonsils and 20 with large tonsils. The tonsils were defined as large when they obstructed two thirds or more of the pharyngeal space; they were considered small if the obstruction was one fourth or less of the pharyngeal space. In patients with small tonsils, consistent velopharyngeal activity was seen most of the time, regardless of the position of the back of the tongue during speech. An association between large tonsils and decreased velopharyngeal activity was found for speech sounds articulated in the back of the mouth. Therefore when examining velopharyngeal activity in hypernasal children, it is important that the speech material include syllables and words with speech sounds articulated in the back of the mouth.

Child↗
PubMed1987

Mandibular coronoid process locking: a prospective study of frequency and association with internal derangement of the temporomandibular joint.

Coronoid process locking has been regarded a rare condition. The literature reveals 59 reports each of one or two cases and an additional two papers reporting on four and six patients, respectively, the latter including hereditary cases. Coronoid process elongation tends to be overlooked when limitation of mouth-opening ability is investigated, since most interest is focused on the joint. To study the frequency of coronoid process hyperplasia and its possible association with TMJ disk displacement, 163 patients with limited mouth-opening ability were examined. All patients were referred for radiographic examination of the TMJs. In eight patients (5%), the limitation of mouth-opening ability was caused by elongation of the coronoid process. Four cases were of congenital origin, and four were secondary to long-standing disk displacement without reduction. The results of this study indicate that elongation of the coronoid process is more common than previously thought. In cases of limited mouth opening, attention should be paid to the possibility of coronoid process locking.

Adolescent↗
PubMed1987

Influence of palatal fistulas on velopharyngeal movements: a cineradiographic study.

Ten patients with hard palate fistulas and velopharyngeal incompetence were examined cineradiographically with lateral and frontal projections during connected speech. The purpose was to study velopharyngeal function for open versus covered fistulas. Fistula length, width, and size were measured. With an open fistula, the degree of lateral pharyngeal wall activity was significantly correlated at the 0.05 level to fistula size. There was no statistically significant correlation between fistula size and the degree of velar activity. With the fistula covered, the velopharyngeal movements improved or even normalized in all patients regardless of fistula size. These findings indicate that patients with both velopharyngeal incompetence and an additional fistula will need covering of the fistula. If velopharyngeal incompetence persists after a temporary covering of the fistula, a combination of velopharyngeal flap surgery and fistula covering ought to be performed to normalize the velopharyngeal activity and speech and resonance.

Adolescent↗
PubMed1986

Hyperplastic soft-tissue formation in the temporomandibular joint associated with internal derangement. A radiographic and histologic study.

Hyperplastic connective tissue formation in the posterior part of the temporomandibular joint glenoid fossa has previously been described in autopsy specimens. The frequency of such hyperplastic tissue formation in patients with long-standing temporomandibular joint pain was studied in 103 joints from 80 patients by means of double-contrast arthrotomography. Five joints in four patients (5%) demonstrated hyperplastic tissue formation; in four cases this was associated with permanently displaced and deformed disks. All five joints were refractory to nonsurgical treatment. Surgically extirpated hyperplastic tissue and disk attachments contained nerve fibers and thickened adventitia of vessels, resulting in narrowed or obliterated lumina, extravasated erythrocytes, and fibrinlike deposits. The synovial membrane showed fibrinoid necrosis or was lost. The pain reaction in temporomandibular joints with hyperplastic soft-tissue formation may be released by compression or tension of nerves, breaking down products from blood or tissue ischemia. Contrast filling of both joint spaces, combined with tomography, was required for detection of the hyperplastic tissue formation.

Adult↗
PubMed1986

Internal derangement of the temporomandibular joint: radiographic and histologic changes associated with severe pain.

In 20 temporomandibular joints (TMJs) (15 patients) with internal derangement associated with severe pain, the presurgical radiographic findings were compared with the morphologic and histologic alterations. Disc extirpation was performed in 17 joints, and in three joints the disc was surgically repositioned. Deformation of the disc observed by double-contrast arthrotomography was verified histologically. Perforation of the posterior disc attachment was seen in two joints; both were associated with osteophyte formation and flattening of the articular eminence. The white disc-like structure in 11 cases was composed of an anterior, stiff, bulgy, biconvex structure combined with a posterior flattened portion that grossly was incorrectly determined to be part of the disc, but that was identified histologically as a posterior disc attachment that had undergone adaptive change characterized by connective tissue hyalinization. In the arthrotomogram the disc position could easily be determined. However, the disc-like clinical appearance of the posterior disc attachment in these cases made determination of disc position at surgery uncertain or impossible. The nonhyalinized posterior disc attachment was intensely red and showed advanced histologic alterations of the vessels, deposits of extravasated erythrocytes and fibrin, and altered composition of the connective tissue. Thus, signs of inflammation were present but without activation of the local immune system since no major inflammatory cell infiltrates were seen. Small accumulations of lymphocytes were seen in only two cases. The surgically extirpated posterior attachments were innervated by silver-positive nerve fibers ranging in diameter from 1 to 15 micron. The severe pain in the TMJs is likely to have originated from this innervated posterior disc attachment or capsule and to have been triggered by the vascular reaction.

Adult↗
PubMed1986

Distribution of substance P-like immunoreactive nerve fibers in temporomandibular joint soft tissues of monkey.

The distribution of substance P-immunoreactive and silver impregnated nerve fibers in the temporomandibular joint soft tissues of the Macaca fascicularis monkey was investigated in frozen sections. The pattern of substance P-immunoreactive structures in the soft tissues and periosteum of the temporomandibular joint was compared with the distribution of silver impregnated nerve fibers within these tissues. Presence of substance P-immunoreactive fibers was demonstrated in the temporomandibular joint capsule, disc attachments, fascia, adjacent periosteum and within the interfascicular connective tissue of the lateral pterygoid muscle. The overall distribution corresponded to that of silver impregnated nerve fibers. Substance P-immunoreactive nerve fibers were found in the adventitia of arteries in all vascularized temporomandibular joint soft tissues but could not be found in the adventitia of veins. No substance P-immunoreactive or silver impregnated nerve fibers were seen in the dense collagenous tissue forming the disc. Substance P is suggested to influence the major features of inflammation and to play a role in acute and chronic pain conditions.

Animals↗
PubMed1986

Tissue reactions associated with internal derangement of the temporomandibular joint. A radiographic, cryomorphologic, and histologic study.

Ten temporomandibular joint specimens, five with clinical signs of arthropathology and five without, were examined by means of tomography, double-contrast tomography, and serial cryosectioning combined with histologic staining of sections for tissue identification. Of the five joints with signs of arthropathology four demonstrated disc displacement. The fifth joint showed a post-traumatic condition. Four of the joints with clinical signs of arthropathology demonstrated hyperplastic connective tissue retaining contrast medium in the posterior part of the fossa. This hyperplastic connective tissue contained extravasated blood and enlarged cavernous structures lacking endothelial lining. Extravasated blood is one probable source of temporomandibular joint pain. All joints with permanently displaced discs demonstrated perforation of a hyalinized posterior disc attachment. Without tissue identification such an attachment is likely to be misinterpreted as being the disc itself.

Aged↗
PubMed1985

Clinical, radiographic, and electromyographic study of patients with internal derangement of the temporomandibular joint.

Fifteen patients with internal derangement of the temporomandibular joint (TMJ) were examined clinically, radiographically, and electromyographically. Electromyographic recordings were also obtained from 11 subjects without signs or symptoms associated with their TMJs or masticatory musculature. All the patients with internal derangement demonstrated interferences on the ipsilateral side. This was interpreted as the result of disc displacement producing a reduced joint space and, consequently, a decreased vertical dimension on the symptomatic side. Slow opening and closing mandibular movements without clenching could be performed by healthy persons without noticeable EMG activity in the temporalis and masseter muscles. In association with disc displacement, electromyographic activity of the temporalis and masseter muscles occurred when the condyle slid over the posterior band of the disc and could be interpreted as an arthrokinetic reflex caused by distraction. Continuous muscle activity could be provoked by TMJ disc displacement and ceased when the disc position was normalized on mouth opening, only to occur again every time the disc became displaced on mouth closure. Anterior disc displacement without reduction (closed lock) could cause spastic activity in the temporalis muscle on the affected side. Spastic activity of the masseter and temporalis muscles occurring on the same side as a joint with anterior disc displacement hinders or inhibits the condylar movement necessary to achieve reduction.

Action Potentials↗
PubMed1984

Salivary calculi and chronic sialoadenitis of the submandibular gland: a radiographic and histologic study.

This study correlated radiographic observations and histologic findings of submandibular glands with the diagnosis of salivary calculus and/or chronic sialoadenitis. During a 15-year period eighty-eight patients satisfied clinical requirements by having a radiographic examination performed prior to gland extirpation. Salivary calculi were present in 83% of the patients. The diagnostic accuracy of radiographs regarding salivary calculi in the submandibular gland system was 92%. Radiolucent calculi constituted 20% of the total number of cases with concrements. Failure to disclose concrements was caused by lack of contrast filling due to a damaged gland which presumably camouflaged radiolucent concretions. Ductal changes observed in sialograms corresponded to histologic changes in the glandular parenchyma in 96% of the cases. The absence of ductal change in sialograms did not necessarily indicate a nondiseased gland.

Adolescent↗
PubMedDate not supplied

Movement of the upper esophageal sphincter and a manometric device during deglutition. A cineradiographic investigation.

A cineradiographic examination of 9 healthy subjects showed asynchronous movement of a manometric device in relation to movement of the upper esophageal sphincter (UES) during deglutition. A single sensor placed within the UES high pressure zone at rest registered pressures existing outside this zone during the major part of deglutition. The manometric device must therefore comprise at least three sensors placed at different levels and about 10 mm apart if consistent pressure recording within this zone is to be achieved. In order to evaluate the pressure profile within the sphincter adequately, cineradiographic determination of the orientation of the measuring device is necessary. This was made possible by insertion of two mutually perpendicular radiopaque indicators into the catheter.

Adult↗
PubMedDate not supplied

The upper esophageal sphincter during normal deglutition. A simultaneous cineradiographic and manometric investigation.

The upper esophageal sphincter was studied during deglutition in 7 healthy subjects using simultaneous cineradiography and manometry. The pressure measuring device consisted of 3 sensors distally placed, and separated by 10 mm. They recorded pressure obliquely to the right at an angle of 15 to 45 degrees anteriorly. During the swallowing sequence a pressure sensor initially placed in the high pressure zone of the sphincter easily slid out of position due to asynchronous movements of the sphincter and the pressure measuring device. These movements can result in erroneous interpretation of pressure recordings. Continuous radiologic monitoring during the entire swallowing sequence thus seems to be mandatory. Immediately before the bolus entered the upper esophageal sphincter, the sphincter relaxed and low or even negative pressures were registered. When the bolus had passed onwards the sphincter contracted gradually, to resume its pre-swallow pressure.

Adult↗