Anne S. McMillan

Intensity-modulated radiotherapy for early-stage nasopharyngeal carcinoma: A prospective study on disease control and preservation of salivary function

Xerostomia is a uniform complication after radiotherapy (RT) for nasopharyngeal carcinoma (NPC). Dosimetric studies suggested that intensity‐modulated RT (IMRT) can spare part of the parotid glands from high‐dose radiation. Disease control and salivary function after IMRT for early‐stage NPC was studied prospectively.

Preservation of quality of life after intensity‐modulated radiotherapy for early‐stage nasopharyngeal carcinoma: Results of a prospective longitudinal study

Xerostomia is a ubiquitous complication after conventional radiotherapy for nasopharyngeal carcinoma (NPC) that seriously impairs patient quality of life (QOL). The effect on QOL of parotid‐sparing intensity‐modulated radiotherapy (IMRT) for early‐stage NPC was assessed prospectively.

Modulation of an inhibitory reflex in single motor units in human masseter by tonic painful stimulation.

Perioral electrical stimuli cause inhibitory reflex responses in single motor-units (SMU) and surface electromyographic (EMG) recordings from voluntary contracted human jaw-closing muscles. Tonic experimental masseter pain has recently been shown to reduce the inhibitory reflex response in surface EMG recordings but the effect on SMU activity has not been described. In this study, motor-unit action potentials were recorded with wire electrodes inserted into the left masseter in eleven subjects. The subjects kept the SMU firing rate around 10 Hz by feedback. Ninety-nine electrical stimuli were applied sequentially to the left mental nerve with increasing stimulus delays in steps of 1 ms after the preceding motor unit action potential. The inhibitory reflex in SMU was recorded before, during and after infusion of hypertonic saline (5%) into the ipsilateral masseter muscle. Spike train data were used to calculate (1) the mean pre- and post-stimulus inter-spike-intervals (ISI) in all of the 99 trials, (2) cumulative changes in firing probability, and (3) estimation of the compound inhibitory post-synaptic potential (IPSP) in the masseter motoneuron. Tonic masseter pain did not change pre-stimulus SMU firing characteristics but the mean ISI for the first post-stimulus discharge (158.2+/-9.2 ms) was significantly decreased compared to the pre-pain (175.8+/-11.3 ms, P<0.05) and post-pain conditions (172. 6+/-11.6 ms, P<0.05). The post-stimulus firing probability was significantly increased and the relative amplitude of the estimated IPSP significantly decreased during tonic masseter pain compared to pre-pain and post-pain conditions. In conclusion, this study indicates that tonic masseter pain has a net excitatory effect on the inhibitory jaw-reflexes, which could be mediated by presynaptic mechanisms on the involved motoneurons.

Salivary gland function and xerostomia in southern Chinese following radiotherapy for nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is rare among Caucasians but very common among southern Chinese. No information is presently available on the relationship between salivary gland function and xerostomia in irradiated southern Chinese. Salivary gland function and xerostomia were measured in irradiated NPC patients, recently diagnosed NPC patients, and a matched control group. Stimulated whole saliva was collected from each participant and flow rate, pH and buffer capacity measured. All participants completed a multi-item dry mouth questionnaire. Comparisons were made using Chi-square and Mann-Whitney tests and correlations assessed using Spearmans rank correlation coefficients. The mean saliva flow rate and pH were significantly lower and the buffer capacity impaired in irradiated NPC patients compared with the other groups (P<0.01). Significantly more irradiated NPC patients had negative impacts associated with dry mouth generally, sticky saliva, and hoarse voice (P<0.01). Subjective dry mouth symptoms and associated reduced saliva flow were also relatively common in non-irradiated participants. Salivary gland hypofunction and xerostomia were major complications in irradiated NPC patients. In irradiated and non-irradiated southern Chinese, subjective dry mouth symptoms appeared to be correlated with actual salivary gland function.

Supra-gingival microbiota in Sjögren’s syndrome

The aim of this study was to investigate the microbiota of noncaries associated supra-gingival plaque (SGP) microbiology in Sjögren’s syndrome (SS). Stimulated whole saliva (SWS) and full-mouth SGP on intact tooth surfaces were collected from 26 primary (p) SS, 27 secondary (s) SS, and 29 control subjects for selective culture of lactobacilli, mutans streptococci, and aerobic and facultatively anaerobic gram-negative rods (AGNR). Predominant cultivable anaerobes from SGP of 11 randomly selected subjects from each group were investigated. Clinical and sialometric data were also collected. SS sufferers had significantly lower SWS flow rate and higher mean DMFT (decayed, missing, filled teeth), while pSS subjects also had lower SWS pH and fewer standing teeth. Lactobacillus acidophilus levels in SWS (P = 0.012) and SGP (P < 0.0001) were significantly elevated in pSS sufferers compared with sSS individuals and controls. AGNR isolation was uncommon. SS sufferers had significantly lower proportion of gram-negative species (P = 0.047). Non-oral species were isolated in greater proportions from pSS SGP (P = 0.007). Subjects with pSS harbored increased levels of L. acidophilus and non-oral species, while SS sufferers generally had lower proportions of gram-negative species. The microbial composition of noncaries associated SGP indicates a potential source of increased caries risk in SS.

Oral carriage of yeasts and coliforms in stroke sufferers: a prospective longitudinal study.

AIM To investigate prospectively the qualitative and quantitative changes in oral carriage of yeasts and coliforms in southern Chinese people suffering from stroke. MATERIALS AND METHODS In 56 elderly people suffering from stroke in a rehabilitation unit of a general medical hospital in Hong Kong, oral microbiological sampling using a combined imprint culture, oral rinse approach and clinical assessment was made during the acute stroke phase, on hospital discharge and 6 months later. RESULTS The oral carriage of yeasts increased significantly during acute stroke (P<0.05), whereas coliform carriage did not. A reduction in oral carriage of yeasts was found on hospital discharge and 6 months later and in coliforms at the 6-month assessment (P<0.05). Candida albicans and Klebsiella pneumoniae were the predominant yeast and coliform respectively. Stroke-related difficulty in tooth brushing and denture wearing were associated with higher oral yeast carriage (P<0.05). We also report here for the first time that the use of aspirin was associated with lower oral yeast carriage in people suffering from stroke. CONCLUSION Oral yeast carriage was closely linked to the level of stroke-related functional disability that improved over time but had not totally resolved 6 months after hospital discharge. The oral reservoir of yeasts and coliforms in people suffering from stroke is noteworthy by care providers as K. pneumoniae may cause aspiration pneumonia.

Oral stereognosis in stroke and Parkinson's disease: a comparison of partially dentate and edentulous individuals

Abstract. Oral stereognosis was measured in partially dentate and edentulous patients with stroke, Parkinsons disease, and an age and gender-matched control group. Stereognostic tests involving conventional free intra-oral manipulation of test objects were undertaken in the partially dentate and edentulous with and without complete dentures. Comparisons were made using the unpaired t-test and ANOVA. Edentulous stroke patients without dentures had significantly greater error scores and fewer correct identifications compared with partially dentate stroke patients. Stereognostic measures were similar in the partially dentate and edentulous with dentures, within experimental groups. In the partially dentate, there were no differences in stereognostic measures between the three groups. Stereognostic measures were poorer in edentulous stroke patients with and without dentures compared with the edentulous control group. Partially dentate stroke patients are less likely to have impaired oral stereognosis than edentulous stroke patients.

A prospective study of the impact of nasopharyngeal cancer and radiotherapy on the psychosocial condition of Chinese patients

Radiotherapy (RT) promises optimistic results in the treatment of nasopharyngeal cancer (NPC). The objective of the current study was to map out prospectively the impact of NPC and RT on patients from diagnosis to 1 year posttreatment.

Effect of oral hygiene interventions on opportunistic pathogens in patients after stroke

BACKGROUND Despite the role of the oral cavity as a reservoir of opportunistic pathogens for infection in patients following stroke, the evaluation of the effects of oral hygiene interventions has been largely neglected. METHODS This randomized clinical trial included 102 patients undergoing hospital-based rehabilitation for stroke. Patients were randomized to one of 3 groups: oral hygiene instruction (OHI) only; OHI and 0.2% chlorhexidine mouth rinse twice daily; or OHI, 0.2% chlorhexidine mouth rinse twice daily, and assisted brushing twice weekly. Oral samples were obtained at baseline and after 3 weeks for detection of Staphylococcus aureus, aerobic and facultatively anaerobic gram-negative bacilli, and yeasts. RESULTS Almost three-quarters (72.8%) of the patients harbored oral anaerobic gram-negative bacilli at baseline, and more than half had detectable S aureus (56.8%) and yeasts (59.3%). Percentage frequencies and viable counts of pathogens remained relatively stable during the course of the clinical trial, and no significant differences were observed among the 3 patient groups. CONCLUSIONS In our study cohort, there was no significant difference in the effectiveness of the 3 different oral hygiene interventions on the prevalence or viable counts of oral opportunistic pathogens.

Depression and diffuse physical symptoms in southern Chinese with temporomandibular disorders

The study investigated the experience of depressive symptoms and the relationship with diffuse physical symptoms reporting in southern Chinese seeking professional care for temporomandibular disorders (TMD) in Hong Kong. Eighty-seven new patients [77 females/10 males; mean age 39.3 years (SD 12.7)] referred to the specialist TMD clinic at the Prince Philip Dental Hospital, Hong Kong participated in this study. The Research Diagnostic Criteria (RDC)/TMD history questionnaire was used to derive Axis II psychological data. Psychological status was assessed through depression and non-specific physical symptoms (NPS) scores (pain items included and excluded) measured with RDC/TMD Axis II instruments; 42.5% of patients experienced moderate/severe depression symptoms; 59.8% and 57.5% had moderate/severe NPS scores when pain items were included and excluded, respectively. Strong, positive and statistically significant correlations were noted between depression scores and the NPS scores that included pain items (r = 0.80) and those that did not (r = 0.80). The correlations remained consistent and were of similar magnitude when male patients were excluded from the computation and also when the possible effect of patient age was controlled. While taking into account the modest patient sample which was related to a low rate of treatment seeking, depressive symptoms were common and similar to other western and Chinese patient groups. NPS reports were higher than in Singapore Chinese patients. There appeared to be a clear association between depression and diffuse physical symptoms. The findings should be considered in the holistic care of Chinese people with TMD.