Influence of age and gender on trigeminal sensory function and magnetically evoked masseteric exteroceptive suppression reflex

ObjectiveThe present study explored the effect of age and gender on trigeminal sensory function and masseteric exteroceptive suppression (ES) reflex responses.MethodsYoung healthy men (n = 12) and women (n = 12) (age: 23.5 ± 3.0 years) and older healthy men (n = 12) and women (n = 12) (age: 58.5 ± 5.2 years) participated. Sensory function was assessed on the skin overlying the mental foramen using mechanical stimuli. Surface EMG was recorded from the left masseter muscle to assess ES reflex responses evoked by a magnetic stimulus applied to the skin above the left mental nerve.ResultsThe older group had significantly higher tactile detection thresholds. Early ES1 was present in all subjects. Onset latency of ES1 was significantly delayed in older subjects. ES2 was present in all young subjects, but only in 5 of the 12 men and 8 of the 12 women in the older group. Significant gender differences were found for sensory and pain thresholds to mechanical stimuli as well as for duration of ES.ConclusionsAgeing affects tactile detection thresholds, onset latency of ES1 responses, and appearance of ES2. The present results indicate that trigeminal sensory function and brainstem reflex responses differ between genders and age groups. These findings may have implications for assessment of craniofacial pain conditions.     

Masticatory performance in older subjects with varying degrees of tooth loss

Objectives

The purpose of this study was to establish the factors influencing the masticatory performance of older subjects with varying degrees of tooth loss and associated numbers of posterior occlusal contacts.

Methods

The subjects consisted of 1274 independently living people aged 60 years and over. Individuals with partially or fully edentulous arches without a denture replacement or those having any symptoms related to an oral problem were excluded from the study participants. Masticatory performance, maximal occlusal force and stimulated whole saliva were measured. Subjects were grouped into three categories by posterior occlusal contact, according to the Eichner Index. Group A had contacts in four support zones; group B had one to three zones of contact or contact in the anterior region only; and group C had no support zones at all, although a few teeth could still remain.

Results

The masticatory performance in groups B and C was found to be 81% and 50% of that of group A, respectively. The multiple linear regression analysis showed that in all the groups, occlusal force was significantly associated with masticatory performance. In groups A and B, the number of residual teeth was significantly associated with masticatory performance, whereas in group C, it had no significant relationship with masticatory performance. Salivary flow rate had a significant correlation with masticatory performance only in group C.

Conclusions

Declines in occlusal contact, occlusal force and salivary flow appear to be associated with reduction of masticatory performance in older adults. However, the crucial factors for masticatory performance varied, depending on the phase of occlusal collapse.     

Genetic Analysis of UGT1A1 Polymorphisms Using Preserved Dried Umbilical Cord for Assessing the Potential of Neonatal Jaundice as a Risk Factor for Autism Spectrum Disorder in Children

Journal of Autism and Developmental Disorders - Neonatal jaundice has been suggested as a perinatal risk factor for autism spectrum disorder (ASD). We examined UGT1A1 polymorphisms to assess the...     

The efficacy and safety of mizoribine for maintenance therapy in patients with myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis: the usefulness of serum mizoribine monitoring

Clinical and Experimental Nephrology - The life prognosis of elderly patients with myeloperoxidase–anti-neutrophil cytoplasmic antibodies-associated vasculitis (MPO-AAV) has been improved by...     

Correction to: Association of initial prednisolone dose with remission,relapse, and infectious complications in adult‑onset minimal change disease

Clinical and Experimental Nephrology - In the original publication, the author has found few errors. The corrections are given below.     

Altered DNA methylation in kidney disease: useful markers and therapeutic targets

Clinical and Experimental Nephrology - Recent studies have demonstrated the association of altered epigenomes with lifestyle-related diseases. Epigenetic regulation promotes biological plasticity...