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Frontal plane mandibular rotations and corresponding hemimandibular translations were studied in vitro by using direct observations of a human cadaver mandible and in vivo by using the indirect observations of rotational electrognathography. A comparison between the two methods showed that rotational electrognathography erred in measuring the clinically relevant hemimandibular translations resulting from mandibular rotations having a unilateral molar point (simulated occlusal interference) as the pivot of frontal plane torque. In vitro frontal plane rotations about a unilateral mandibular molar tooth (simulated occlusal interference) suggested that the resulting hemimandibular upward translations of the lateral portion of the mandibular condyle, contralateral to the molar tooth, would cause considerable compressive loading of the temporomandibular joint disc. [ABSTRACT FROM AUTHOR]

In 12 subjects, a pliable, yet unbreakable, intercuspal interference (aluminium shim onlay splint; uniform height of 0.25 mm) was placed between either the right or left maxillary and mandibular second premolars and first molars. During brief and forceful biting (dynamic chewing stroke of about 20 kg force) the interference emulated a semisoft food bolus, and at the end of biting (subsequent static clenching stroke of about 20 kg force) it emulated a rigid metal interference. During dynamic/static biting, rotational electrognathography measured maximum frontal and horizontal plane torque of the right and left mandibular condyles. Eleven subjects (92%) showed frontal plane upward rotation (mean of 1.0°) of the condyle contralateral to the interference, and one subject (8%) showed frontal plane upward rotation (0.4°) of the condyle ipsilateral to the interference. Two subjects (17%) showed no horizontal plane rotation; seven subjects (58%) showed backward rotation (mean of 0.4°) of the condyle contralateral to the interference; and three subjects (25%) showed backward rotation (mean of 0.3°) of the condyle ipsilateral to the interference. It is suggested that, in the presence of an occlusal interference, mastication may have both short-and long-term detrimental effects. [ABSTRACT FROM AUTHOR]

A rigid intercuspal interference (minimum mean height of 0.24 mm) was placed on either the right or left mandibular second premolar and first molar of 12 subjects. During brisk and forceful biting on the interference, rotational electrognathography measured maximum torque of the right and left mandibular condyles in the frontal and horizontal planes of orientation. All subjects showed frontal plane upward rotation (mean of 0.7 degrees) of the mandibular condyle contralateral to the interference. In 33% of the subjects there was no horizontal plane rotation. In 58% of the subjects there was horizontal plane backward rotation (mean of 0.5 degrees) of the mandibular condyle ipsilateral to the interference, and in one subject (8%) there was backward horizontal plane rotation (0.1 degree) of the mandibular condyle contralateral to the interference. It was inferred that the masseter muscle, ipsilateral to the interference, generated negative work in order to decelerate frontal plane 'unseating' of the mandibular condyle ipsilateral to the interference. It was inferred that the masseter muscle, contralateral to the interference, produced positive work in order to accelerate frontal plane 'seating' of the mandibular condyle contralateral to the interference. Finally, it was speculated that the impact forces of frontal plane 'seating' of the mandibular condyle, contralateral to the interference, might lead to 'vacuum sticking' of the temporomandibular joint disc because of the formation of negative hydrostatic pressures. [ABSTRACT FROM AUTHOR]

Acute suppurative thyroiditis (AST) and thyroid abscess are rare. While in younger individuals infection usually spreads locally through the pyriform sinus, older adults are more susceptible to hematogenous seeding of the thyroid gland. Here, we describe a case of AST with thyrotoxicosis, where the clinical course deteriorated rapidly due to abscess formation. Despite early diagnosis and appropriate antibiotic therapy, abscess drainage was eventually required. Thyroid function tests are typically normal, while frank thyrotoxicosis is unusual and should not divert clinical suspicion from AST. Timely diagnosis and treatment of AST are crucial in order to avoid serious and potentially devastating complications. We emphasize significance of a high index of suspicion, appropriate treatment approach and high yield of serial imaging studies in timely diagnosis and decision making to treat AST. [ABSTRACT FROM AUTHOR]

Summary: The microcirculation plays an important role in bone health. Here, we examine whether albuminuria, a marker of renal microvascular disease, is associated with the risk of hip fracture in older adults (age, 78 years). We find a small independent association in women but not in men. Introduction: The microvascular circulation plays an important role in bone physiology. Two studies of middle-aged adults have found that albuminuria ( > 30 mg albumin/g creatinine), a disorder of the renal microvasculature, is associated with fracture risk. Here, we examine whether albuminuria is related to hip fracture risk and reduced hip bone mineral density (BMD) in older adults with a mean age of 78 years. Methods: From the Cardiovascular Health Study (41 % male), 3,110 adults with albuminuria testing were followed up for incident hip fracture for up to 9.5 years. BMD was performed in a subset of 1,208 participants. Results: There were 313 hip fractures during follow-up (7.7 % of men; 11.7 % of women). The incidence rate for men, with and without albuminuria, was 1.43 and 0.93/100 person-years of follow-up ( p = 0.02); for women, 1.84 and 1.33 ( p = 0.04). After adjustment for osteoporosis-related factors, frailty and falling, a doubling of albuminuria was significantly associated with hip fracture risk in women (hazard ratio, 1.12, 95 % CI, 1.001–1.25), but not in men. In the subcohort with BMD measurement, increased urine albumin levels were significantly associated with decreased total hip BMD in men (−0.009 g calcium/cm 2 (−0.017, −0.001); p = 0.04), but not in women. Conclusions: In older women, albuminuria is associated with a small, but statistically significant, increased risk of hip fracture independent of other explanatory factors. No such risk appears to be present in men, although their total hip BMD is lower in association with albuminuria. [ABSTRACT FROM AUTHOR]

Background/Objective: Pulmonary tuberculosis (TB) is a common worldwide lung infection. It remains an important cause of morbidity and mortality. Radiographic manifestations of pulmonary tuberculosis are diverse and varied. This study was performed to define the various radiographic manifestations of this infection in the pediatric age group in children who were referred to Mofid Children's Hospital. Patients and Methods: We reviewed chest x-rays of 30 pulmonary TB patients admitted to our hospital to ascertain the extent of parenchymal and mediastinal involvements on chest xray. Results: Male to female ratio was 1.7:1. The patients' age ranged from 2-163 months with a mean age of 36.9 months. Mediastinal lymphadenopathy was detected in 90% of the cases and pulmonary involvement, especially alveolar shadowing was seen in 83.3% of the cases (of which 43.3% had an air-space pattern and 40% had an interstitial pattern). 19 of the 30 patients (66.3%) were under 36 months, in which 17 of the 19 patients (89.5%) revealed lymphadenopathy. Therefore 63% of all detected lymphadenopathies were seen in this age group. Mediastinal lymphadenopathy was more common on the right side (73.3%). Furthermore, 60% of all alveolar infiltrations were seen on the right side. Conclusion: Pulmonary tuberculosis most commonly represents as a mediastinal and thereafter as a parenchymal involvement. Hilo-mediastinal lymphadenopathy is the most common presentation in infants and young children. [ABSTRACT FROM AUTHOR]