Staging of osteonecrosis of the jaw requires computed tomography for accurate definition of the extent of bony disease

Management of osteonecrosis of the jaw associated with antiresorptive agents is challenging, and outcomes are unpredictable. The severity of disease is the main guide to management, and can help to predict prognosis. Most available staging systems for osteonecrosis, including the widely-used American Association of Oral and Maxillofacial Surgeons (AAOMS) system, classify severity on the basis of clinical and radiographic findings. However, clinical inspection and radiography are limited in their ability to identify the extent of necrotic bone disease compared with computed tomography (CT). We have organised a large multicentre retrospective study (known as MISSION) to investigate the agreement between the AAOMS staging system and the extent of osteonecrosis of the jaw (focal compared with diffuse involvement of bone) as detected on CT. We studied 799 patients with detailed clinical phenotyping who had CT images taken. Features of diffuse bone disease were identified on CT within all AAOMS stages (20%, 8%, 48%, and 24% of patients in stages 0, 1, 2, and 3, respectively). Of the patients classified as stage 0, 110/192 (57%) had diffuse disease on CT, and about 1 in 3 with CT evidence of diffuse bone disease was misclassified by the AAOMS system as having stages 0 and 1 osteonecrosis. In addition, more than a third of patients with AAOMS stage 2 (142/405, 35%) had focal bone disease on CT. We conclude that the AAOMS staging system does not correctly identify the extent of bony disease in patients with osteonecrosis of the jaw.     

Postpartum thyroid dysfunction and HLA status

Nine-hundred-and-one women presenting in an antenatal clinic at the 60th week of pregnancy were tested for antithyroid antibodies. A group of 113 antibody-positive women and 108 antibody-negative age-matched controls were HLA typed and followed prospectively at 6-weekly intervals through pregnancy and for 12 months postpartum. Forty-five of the women developed biochemical evidence of postpartum thyroid dysfunction (PPTD) of whom 36 were antibody positive. Compared with a local control population (n = 600), and using multiplex analysis, there was a significant increase in the combinations HLA B8, DR3 and HLA A1, B8, DR3 from 22.5% to 40.0% (P less than 0.02) and from 18.6% to 35.6% (P less than 0.01) respectively in the women who developed PPTD. The well-recognized association of these haplotypes with other organ-specific autoimmune diseases provides further support for autoimmune events being implicated in the development of PPTD.     

Differential labeling of the vestibular complex following unilateral injections of horseradish peroxidase into the cat and rat locus coeruleus

In anaesthetized cats, lumbar dorsal horn neurons were excited by brief noxious radiant heating of glabrous hindpaw skin. These nociceptive responses were inhibited by concomitant repetitive electrical stimulation of the ipsilateral deep radial nerve. Noxious heat responses were linearly correlated with skin temperature during heating. The slope of this stimulus-response function was decreased, and the response threshold increased, by deep radial nerve stimulation. Microinjection of lidocaine into the medullary raphe attenuated the inhibition induced by deep radial nerve stimulation. The results indicate that in the cat, ‘diffuse noxious inhibitory controls’ (DNIC) involve medial medullary regions.     

Hypophysectomy does not alter the effects of somatostatin or growth hormone on canine splanchnic biogenic amine release

We have demonstrated previously that growth hormone (GH) and somatostatin (somatotropin release inhibitory factor, SRIF) exert comparable effects on the release of splanchnic biogenic amines. The purpose of the present investigation was to study further the response of the two hormones and see whether the similarity persists in dogs completely deprived of endogenous GH. Experiments were conducted in seven hypophysectomized dogs fitted with an indwelling portal catheter. Two to 4 weeks after surgery the responsiveness of their catecholaminergic neurons was tested by an injection of human beta-endorphin (20 micrograms/kg); it caused a rise in portal catecholamine levels equivalent to that seen in intact dogs. Then the effect of a spike concentration of SRIF or GH on hepatic portal and peripheral levels of free serotonin and catecholamines was studied, all by radioenzymatic methods. The intravenous injection of ovine GH (100 micrograms/kg) or equimolar amounts of SRIF (7.5 micrograms/kg) produced in the hepatic portal circulation a transient but statistically significant rise of serotonin and a concomitant reduction in the concentration of dopamine, norepinephrine, and epinephrine. No changes were found in the peripheral circulation. The response patterns to SRIF or GH were virtually identical, which is in keeping with our other data, suggesting that the effect of GH on splanchnic biogenic amine secretion is SRIF-dependent and mediated by SRIF-containing neurons.(ABSTRACT TRUNCATED AT 250 WORDS)     

Surgical Treatment for Patients With Periodontal Disease Reduces Risk of End‐Stage Renal Disease: A Nationwide Population‐Based Retrospective Cohort Study

Background: The association between periodontal disease treatment and end‐stage renal disease (ESRD) remains unclear. This study aims to determine whether surgical periodontal treatment reduces ESRD risk. Methods: From the insurance claims data of patients with periodontal disease who were free of ESRD from 1997 to 2009, 35,496 patients were identified who underwent surgery for subgingival curettage and/or periodontal flap and are considered the treatment cohort. For comparison, 141,824 patients who did not undergo these treatments were considered the no‐treatment cohort. Follow‐ups were performed until the end of 2009 to estimate the incidence and risk of ESRD in these two cohorts. Cox proportional hazard regression was used to estimate the related hazard ratio (HR) and 95% confidence interval (CI) of ESRD. Results: The incidence of ESRD was lower in the treatment cohort than in the no‐treatment cohort (4.66 versus 7.38 per 10,000 person‐years), with an adjusted HR of 0.59 (95% CI = 0.46 to 0.75). Sex‐ and age‐specific analysis showed that the incidence rate ratio of the treatment cohort to the no‐treatment cohort was higher for women than for men and declined with age. The risks of ESRD were consistently lower in the treatment cohort even when compared by comorbidity. Conclusions: Patients with periodontal disease who undergo procedures for subgingival curettage and/or periodontal flap have a remarkably decreased risk of ESRD.