Analysis of complications following surgical treatment of benign parotid disease

Background: The objective of the study was to study the incidence of, and risk factors for developing complications following parotidectomy for benign disease, to improve preoperative patient counselling and better inform future surgical management. Methods: An 11‐year retrospective review of 162 parotidectomies for benign disease, collecting and analysing data about presentation, investigations, surgical treatment, postoperative facial nerve function, Frey’s syndrome and other surgical complications. Results: The mean age at presentation was 58 years. The commonest pathology was benign pleomorphic adenoma (43%), followed by Warthin’s tumour (30%) and chronic sialadenitis (22%). Sialadenitis was a significant risk factor for facial nerve palsy and increased the incidence of salivary fistulas. Parotid duct ligation increased the risk of nerve palsy in the distribution of zygomatic and buccal branches. Operations for Warthin’s tumour were associated with an increased risk of dysfunction of the cervical branch of the nerve. Half the patients had intraoperative facial nerve stimulation and this did not influence the likelihood of facial paresis. The recovery of facial nerve function showed a biphasic distribution, with 90% of patients having normal function within 12 months, followed by a slower recovery rate for up to 2 years. Conclusion: The incidence of postoperative complications was influenced by the pathology, with inflammatory lesions significantly increasing the risk of facial nerve dysfunction and other complications, but also by variations in surgical practice, such as parotid duct ligation. Overall, the incidence of permanent facial paralysis was less than 2%, but temporary nerve palsy was common at 40%, with most patients regaining normal function within 1 year of the operation.     

The Effect of Tapering Period on Plasma Pro-Inflammatory Cytokine Levels and Performance in Elite Male Cyclists

The aim of this study was to investigate the effect of two different tapering period lengths on the concentration of plasma interleukin- 6 (IL-6), interleukin (IL-1β) and tumor necrosis factor-α (TNF-α) and performance in elite male cyclists. To this end, after completing 8 weeks progressive endurance exercise, twenty four high-level endurance cyclists were randomly assigned to one of two groups: a control group of cyclists (n = 12) continued performing progressive weekly training volume for 3 weeks while a taper group of cyclists (n = 12) proceeded with a 50% reduction in weekly training volume relative to the control group. A simulated 40 min time trial (40TT) performance ride was used as the criterion index of performance before and after the tapering period to evaluate the physiological and performance effects of each protocol. Blood samples were collected immediately post-40TT from all participants at the beginning of week 1, and the end of weeks 4, 8, 9 and 11. IL-1β, IL-6 and TNFα were assayed using a standard commercial ELISA kits (Quantikine; R & D Systems, Minneapolis, MN). The mean time to complete the 40TT in the taper group decreased significantly (p < 0.01) after both 1 and 3 weeks with reduced training volume relative to the control group. There were significant reductions in (p < 0.001) IL-1β, IL-6 and TNFα concentrations in the taper group relative to the control group at the end of the 3 week tapering period, but not at the end of the 1 week tapering period. These results demonstrate that both a 1 and a 3 week taper period will result in improved physical performance in trained cyclists but only a 3 week taper period will result in attenuation of post-exercise pro- inflammatory cytokines when compared to those continuing a more intense training regimen.

Key points

• The excessive endurance exercise-induced elevations in pro-inflammatory cytokines would, in turn, stimulate the release of anti-inflammatory cytokines.
• Elevations in pro-inflammatory cytokines indicate athletes are highly susceptible to infections.
• 1and 3-week taper periods will reduce circulating pro-inflammatory cytokine levels thereby possibly limiting the chances of infection and potentially reducing the effects of these cytokines in inducing fatigue-like symptoms in athletes.

Key words: Endurance training, immune, performance, interleukin-1β, interleukin-6, Tumor necrosis factor α.     

Morphine state-dependent learning sensitization and interaction with nitric oxide

In the present study, the effects of nitric oxide (NO) precursor L-arginine and L-NAME, a potent inhibitor of NO synthase (NOS), on the expression of sensitization of morphine were investigated. Pre-training administration of morphine (5 mg/kg) impaired memory retrieval compared to pre-training saline-treated animals. Amnesia due to pre-training morphine (5 mg/kg) was restored by pre-test morphine (5 mg/kg).The retrieval impairment was also inhibited in mice which had received once-daily injections of morphine (20 and 30 mg/kg, s.c.) for 3 days, followed by 5 days of no drug treatment before training (in order to induce morphine sensitization). Administration of L-arginine (60 mg/kg/day - 3 days) or L-NAME (20 mg/kg/day - 3 days) before training did not alter morphine state dependency. During acquisition of sensitization, administration of L-arginine (60 mg/kg) 20 min before morphine (10 mg/kg/day, for 3 days) increased, while injection of L-NAME (20 mg/kg) 20 min before morphine (30 mg/kg/day, for 3 days) decreased morphine state dependency. It is concluded that NO is involved in the morphine-induced sensitization.     

An overview of recent progress in dental applications of zinc oxide nanoparticles

Nanotechnology is an emerging field of science, engineering, and technology concerning the materials in nanoscale dimensions. Several materials are used in dentistry, which can be modified by applying nanotechnology. Nanotechnology has various applications in dentistry to achieve reliable treatment outcomes. The most common nanometals used in dental materials are gold, silver, copper oxide, magnesium oxide, iron oxide, cerium oxide, aluminum oxide, titanium dioxide, and zinc oxide (ZnO). ZnO nanoparticles (NPs), with their unparalleled properties such as high selectivity, enhanced cytotoxicity, biocompatibility, and easy synthesis as important materials were utilized in the field of dentistry. With this background, the present review aimed to discuss the current progress and gain an insight into applications of ZnO NPs in nanodentistry, including restorative, endodontic, implantology, periodontal, prosthodontics, and orthodontics fields.

Nanodentistry is an emerging field of nanotechnology in order to improvement dental treatment, care and prevention of oral diseases.