Hemodynamics of the oral mucosa during cooling: A crossover clinical trial.

Objective: Oral cryotherapy is used to prevent the onset of oral mucositis, a common and debilitating adverse effect following cancer chemotherapy. A protective mechanism associated with oral cooling is thought to be mediated through reduced tissue microcirculation. The aim of the present study was to examine the underlying mechanism associated with oral mucosal cooling by measuring oral microcirculation and tissue oxygen saturation after cooling with ice chips (IC) and an intraoral cooling device (ICD). Study design: In a single-center randomized crossover study, 10 healthy volunteers were assigned (1:1) randomly to the order in which the two intraoral cooling procedures (IC/ICD) were to be commenced. On day 1, half of the study participants started with IC and then crossed over to intraoral cooling with the ICD on day 2, while the other half of the participants undertook the same two procedures in the reverse order. Total and functional capillary density (T/FCD) and tissue oxygen saturation (StO2) measurements were obtained at baseline and 30 min following oral cooling. Results: Following 30 min of oral cooling, a statistically significant difference was found for FCD between IC and ICD (percentage points; +2 vs. -13; p < 0.05). A statistically significant decrease in StO2 was observed with both IC and ICD (%; 13 vs. 10) after 30 min of cooling as compared to baseline (p < 0.05). As for the participants' preference the ICD was preferred over IC by 9 out of 10 participants (p = 0.021). Conclusions: Both microcirculation parameters and tissue oxygen saturation are altered in conjunction with oral cooling, indicating their potential mechanistic contribution towards cryoprevention of oral mucositis.

Outcome of a rabbit model for late irradiation effects in mandibular oral mucosa and bone: A pilot study.

BACKGROUND/AIM/OBJECTIVE: Late side effects of radiotherapy (RT) in the treatment for head and neck (HN) malignancies involve an inadequate healing response of the distressed tissue due to RT-induced hypovascularity. The aim of this study was to develop a pilot model in which vascular alterations associated with the onset of late irradiation (IR) injury could be measured in rabbit oral mucosa and mandibular bone. MATERIALS AND METHODS: Eight male New Zealand white rabbits were divided over four treatment groups. Group I-III received four fractions of RT (5.6 Gy, 6.5 Gy, and 8 Gy, respectively) and Group IV received 1 fraction of 30 Gy. Oral microcirculatory measurements were performed at baseline (before RT) and once a week during 11 consecutive weeks after RT assessing perfusion parameters, that is, total vessel density (TVD), perfused vessel density (PVD), proportion of perfused vessels (PPV), and microvascular flow index (MFI). Post-mortem histopathology specimens were analyzed. RESULTS: Five weeks after RT, TVD, and PVD in all groups showed a decrease of >10% compared to baseline, a significant difference was observed for Groups I, II, and IV (P<0.05). At T11, no lasting effect of decreased vessel density was observed. PPV and MFI remained unaltered at all-time points. Group IV showed a marked difference in scattered telangiectasia such as microangiopathies, histological necrosis, and loss of vasculature. CONCLUSION: No significant lasting effect in mucosal microcirculation density due to IR damage was detected. Observed changes in microcirculation vasculature and histology may align preliminary tissue transition towards clinical pathology in a very early state associated with late IR injury in the oral compartment. RELEVANCE FOR PATIENTS: Enhancing knowledge on the onset of late vascular IR injury in the HN region could help the development, monitoring, and timing of therapies that act on prevention, discontinuation, or repair of radiation pathology.

Effects of sterilization on the mechanical properties of poly(methyl methacrylate) based personalized medical devices.

BACKGROUND: Nowadays, personalized medical devices are frequently used for patients. Due to the manufacturing procedure sterilization is required. How different sterilization methods affect the mechanical behavior of these devices is largely unknown. MATERIALS AND METHODS: Three poly(methyl methacrylate) (PMMA) based materials (Vertex Self-Curing, Palacos R+G, and NextDent C&B MFH) were sterilized with different sterilization methods: ethylene oxide, hydrogen peroxide gas plasma, autoclavation, and γ-irradiation. Mechanical properties were determined by testing the flexural strength, flexural modulus, fracture toughness, and impact strength. RESULTS: The flexural strength of all materials was significantly higher after γ-irradiation compared to the control and other sterilization methods, as tested in a wet environment. NextDent C&B MFH showed the highest flexural and impact strength, Palacos R+G showed the highest maximum stress intensity factor and total fracture work. CONCLUSION: Autoclave sterilization is not suitable for the sterilization of PMMA-based materials. Ethylene oxide, hydrogen peroxide gas plasma, and γ-irradiation appear to be suitable techniques to sterilize PMMA-based personalized medical devices.

Assessment of obstructive sleep apnoea treatment success or failure after maxillomandibular advancement.

Maxillomandibular advancement (MMA) is an alternative therapeutic option that is highly effective for treating obstructive sleep apnoea (OSA). MMA provides a solution for OSA patients that have difficulty accepting lifelong treatments with continuous positive airway pressure or mandibular advancement devices. The goal of this study was to investigate the different characteristics that determine OSA treatment success/failure after MMA. The apnoea-hypopnoea index (AHI) was used to determine the success or failure of OSA treatment after MMA. Sixty-two patients underwent MMA for moderate and severe OSA. A 71% success rate was observed with a mean AHI reduction of 69%. A statistically significant larger neck circumference was measured in patients with failed OSA treatments following MMA (P=0.008), and older patients had failed OSA treatments with MMA: 58 vs. 53 years respectively (P=0.037). Cephalometric analysis revealed no differences between successful and failed OSA treatment outcomes. There was no difference in maxillary and mandibular advancements between success and failed MMA-treated OSA patients. The complications most frequently reported following MMA were sensory disturbances in the inferior alveolar nerve (60%) and malocclusion (24%). The results suggest that age and neck girth may be important factors that could predict susceptibility to OSA treatment failures by MMA.

Is pelvic organ prolapse associated with altered microcirculation of the vaginal wall?

AIMS: Vascularisation of the vagina is necessary for optimal function and support of the surrounding organs. We evaluated whether vaginal microcirculation, as representative of vascularisation, differs between women with and without pelvic organ prolapse (POP). METHODS: In 17 women with POP-Q stage ≥2 and 10 women without POP measurements were performed using sidestream dark-field imaging (groups were not matched). POP and non-POP sites were compared in women with a single compartment prolapse (n = 7). Morphology of the microvessels was scored using the microcirculatory architecture and capillary tortuosity scores at four regions of the vaginal wall. Capillary density measurements were performed and microvascular flow was assessed according to the microvascular flow index (MFI) score. RESULTS: Architecture and tortuosity scores were similar for each anatomical region between women with and without POP and between the POP and non-POP site. A statistically significant difference in capillary density in the left vaginal wall between women with and without POP was observed (25.8 vs. 34.0, P = 0.049). No significant differences in capillary density were observed between the POP and non-POP site. Average MFI scores revealed a continuous flow for all four regions in patients with and without POP. CONCLUSIONS: Vaginal microcirculatory architecture, capillary density, and microvascular flow are similar in women with and without POP. Our method to assess the microcirculation of the vaginal wall is consistent in women with POP, which generates an opportunity to assess vaginal microcirculation in the (surgical) treatments of POP. Neurourol. Urodynam. 35:764-770, 2016. © 2015 Wiley Periodicals, Inc.

Patient discomfort and other side effects after bilateral sagittal split osteotomy or distraction osteogenesis of the mandible: a randomized clinical trial.

A randomized clinical trial was conducted to compare bilateral sagittal split osteotomy (BSSO) with distraction osteogenesis (DO) for the advancement of the mandible, with a focus on patient discomfort, postoperative pain, the need for analgesics, and occurrence of infection. All patients were non-syndromal, had a class II hypoplastic mandible, and had not undergone previous mandibular surgery. A total of 66 patients were allocated randomly to the BSSO group (32 patients) or the DO group (34 patients). Sixty-three patients were eligible for evaluation, 29 in the BSSO group and 34 in the DO group. Patients in the DO group experienced more pain after 6 days postoperative, and were administered more analgesics after 5 days postoperative than patients in the BSSO group (P=0.030 and P=0.045, respectively). The operating time was significantly shorter for the BSSO group than for the DO group (78 min vs. 100 min, P=0.024). All postoperative infections (12 in total) emerged in the DO group (P=0.005). All patients in the DO group had a second surgery in day care to remove the distractor, while two patients in the BSSO group needed plate removal. It is concluded that patients experienced more pain after DO, needed more analgesics postoperatively, and had more infections in comparison to the BSSO group.