Practical guide for safe sedation.

This practical guide has been developed to ensure safe and effective sedation performed in adult patients outside of the operating room, for instance in intensive care units and dental treatment rooms and in the field of palliative care. Sedation levels are classified based on level of consciousness, airway reflex, spontaneous ventilation, and cardiovascular function. Deep sedation induces loss of consciousness and protective reflexes, and can cause respiratory depression and pulmonary aspiration. Invasive medical procedures necessitating deep sedation include cardiac ablation, endoscopic submucosal dissection, and internal radiation therapy. Appropriate analgesia is necessary for procedures that require deep sedation. The sedationist should evaluate the risks of the planned procedure, explain the sedation process to the patient, and obtain the patient's informed consent. Major parameters to be evaluated preoperatively are the patient's airway and general condition. Equipment, instruments, and drugs necessary for emergency situations should be defined and routinely maintained. To prevent aspiration, patients scheduled for moderate or deep sedation should fast preoperatively. In both inpatients and outpatients, biological monitoring should be continued until the discharge criteria are met. Anesthesiologists should be involved in management systems that ensure safe and effective sedation even if they do not personally perform all sedation procedures.

Coordinated features in jaw and neck muscle activities induced by chewing of soft and hard gum in healthy subjects.

BACKGROUNDS: Jaw and neck muscles may be activated by chewing load using a hard food. However, it remains unclear how effects the gum hardness to the coordinated features in jaw and neck muscle activities during chewing performance. OBJECTIVES: This study was conducted to quantitatively elucidate the effects of the hardness of the gum on coordinated features in jaw and neck muscle activities using intermuscular EMG-EMG transfer function and EMG-EMG coherence function analyses in 18 healthy subjects. METHODS: Jaw and neck muscle activities were aggregated into the first peak frequency of the power spectrum, and power, gain, phase, and coherence parameters between jaw and neck muscle activities were examined in the first peak frequencies during soft and hard gum chewing. RESULTS: The first peak frequency was not significantly different between soft and hard gum chewing. In contrast, power values of the jaw and neck muscles were significantly increased by chewing of hard gum as compared with soft gum, whereas gain, phase, and coherence were not significantly changed by gum hardness. CONCLUSIONS: The chewing rhythm, the quantitative and temporal coordination, and the functional coordination in jaw and neck muscle activities were not changed during soft and hard gum chewing, as well as increased jaw and neck muscles activities. It is therefore concluded that the chewing rhythmicity and jaw and neck muscles coordination accompanied with the increased jaw and neck muscle activities are maintained under the condition of the chewing load using gum hardness in the healthy individuals.

Activation of Prefrontal Cortex in Process of Oral and Finger Shape Discrimination: fNIRS Study.

BACKGROUND: The differences in the brain activities of the insular and the visual association cortices have been reported between oral and manual stereognosis. However, these results were not conclusive because of the inherent differences in the task performance-related motor sequence conditions. We hypothesized that the involvement of the prefrontal cortex may be different between finger and oral shape discrimination. This study was conducted to clarify temporal changes in prefrontal activities occurring in the processes of oral and finger tactual shape discrimination using prefrontal functional near-infrared spectroscopy (fNIRS). METHODS: Six healthy right-handed males [aged 30.8 ± 8.2 years (mean ± SD)] were enrolled. Measurements of prefrontal activities were performed using a 22-channel fNIRS device (ETG-100, Hitachi Medical Co., Chiba, Japan) during experimental blocks that included resting state (REST), nonsense shape discrimination (SHAM), and shape discrimination (SHAPE). RESULTS: No significant difference was presented with regard to the number of correct answers during trials between oral and finger SHAPE discrimination. Additionally, a statistical difference for the prefrontal fNIRS activity between oral and finger shape discrimination was noted in CH 1. Finger SHAPE, as compared with SHAM, presented a temporally shifting onset and burst in the prefrontal activities from the frontopolar area (FPA) to the orbitofrontal cortex (OFC). In contrast, oral SHAPE as compared with SHAM was shown to be temporally overlapped in the onset and burst of the prefrontal activities in the dorsolateral prefrontal cortex (DLPFC)/FPA/OFC. CONCLUSION: The prefrontal activities temporally shifting from the FPA to the OFC during SHAPE as compared with SHAM may suggest the segregated serial prefrontal processing from the manipulation of a target image to the decision making during the process of finger shape discrimination. In contrast, the temporally overlapped prefrontal activities of the DLPFC/FPA/OFC in the oral SHAPE block may suggest the parallel procession of the repetitive involvement of generation, manipulation, and decision making in order to form a reliable representation of target objects.

Effects of denture wearing on coordinated features of jaw and neck muscle activities during chewing in partially edentulous elderly patients.

PURPOSE: This study was performed to examine how denture wearing improves jaw and neck muscle coordination during chewing in partially edentulous elderly patients. METHODS: Sixteen patients classified as Eichner's index B2 or B3 and 16 young dentate subjects were enrolled. Jaw and neck muscle activities during chewing were recorded using electromyography with and without denture wearing, then analyzed using intermuscular Electromyography (EMG)-EMG transfer and EMG-EMG coherence function analyses to clarify quantitative, temporal, and functional coordination of jaw and neck muscle activities while chewing. Occlusal force and masticatory scores were also determined. RESULTS: Denture wearing increased the power values for jaw closing muscle activities, and improved occlusal area and force, and masticatory score. Gain values for jaw closing and opening muscle activities were decreased in those wearing dentures compared to those not wearing dentures. Denture wearing resulted in equivalent gain values for jaw closing and opening muscle activities as compared to the young subjects. Coherence values for chewing and non-chewing side neck muscle activities were increased as compared to not denture wearing. CONCLUSIONS: The suitability of denture wearing can be evaluated from the viewpoint of gain as a quantitative parameter showing coordination between jaw closing and opening muscle activities. Such evaluation can be performed from the viewpoint of coherence as a parameter of functional coordination between jaw and neck muscle activities during chewing in partially edentulous elderly patients. The gain parameter in regard to jaw muscle activities may be compensated to a state equivalent to that seen in young subjects by wearing an appropriate denture.

Quantitative and qualitative assessment of sensory changes induced by local anesthetics block of two different trigeminal nerve branches.

OBJECTIVES: The aims were to use different techniques to assess the degree of sensory changes and magnitude of perceived size changes in the facial region induced by nerve blocks of two different trigeminal nerve branches in healthy participants. MATERIALS AND METHODS: This placebo-controlled study included 30 healthy volunteers. The participants underwent quantitative and qualitative sensory testing (QST and QualST) thrice: before, 10 min, and 2 h after mental (n = 15) and infraorbital (n = 15) nerve blocks and during control (saline) sessions. Perceived numbness, temperature changes, and perceptual distortion were also measured at all time points during the nerve block and control sessions. Differences in outcome parameters between the sessions and time points were analyzed using analyses of variance and McNemar's tests. RESULTS: There was a significant degree of sensory loss to most QST and all QualST parameters, with significant numbness and increased perceived size at the injection site 10 min and 2 h after the nerve blocks compared with saline (P < 0.030) and the baseline (P < 0.042). Two hours after the nerve blocks, the sensitivity was significantly closer to baseline than after 10 min to most of the QST parameters (P < 0.011). CONCLUSIONS: QST and QualST revealed that the nerve blocks in the orofacial region resulted in complete or partial blockade of afferent nerve fibers mediating thermal and mechanical function for more than 2 h with significant numbness and perceptual distortion. CLINICAL RELEVANCE: Both QST and QualST can provide information on the degree of blockade of afferent nerve fibers after nerve blocks in the orofacial region.

Prefrontal Consolidation and Compensation as a Function of Wearing Denture in Partially Edentulous Elderly Patients.

BACKGROUND: The cognitive effects of wearing a denture are not well understood. This study was conducted to clarify the effects of denture use on prefrontal and chewing muscle activities, occlusal state, and subjective chewing ability in partially edentulous elderly individuals. METHODS: A total of 16 partially edentulous patients were enrolled. Chewing-related prefrontal cortex and jaw muscle activities were simultaneously examined using a functional near-infrared spectroscopy (fNIRS) device and electromyography, under the conditions of unwearing, and wearing a denture. Occlusal state and masticatory score were also determined under both conditions. Using multiple linear regression analysis, associations between prefrontal and chewing activities with wearing were examined using change rates. RESULTS: Chewing rhythmicity was maintained under both conditions. As compared with unwearing, the wearing condition was associated with improved prefrontal cortex and chewing muscle activities, occlusal state in regard to force and area, and masticatory score. Also, prefrontal activities were positively associated with burst duration and peak amplitude in masseter (Mm) and temporal muscle activities, as well as masticatory scores. In contrast, prefrontal activities were negatively associated with occlusal force. CONCLUSION: Wearing a denture induced a positive association between burst duration and peak amplitude in Mm and temporal muscle activities and prefrontal activity, which may indicate a parallel consolidation of prefrontal cortex and rhythmical chewing activities, as well as masticatory scores. On the other hand, denture use induced a negative association of occlusal force with prefrontal activities, which might suggest that prefrontal compensative associations for the physiocognitive acquisition depended on biomechanical efficacy gained by wearing a denture.

A Case of Laryngeal Granuloma Likely Caused by Laryngopharyngeal Reflux Disease Following a Sagittal Split Ramus Osteotomy.

Laryngeal granuloma is an uncommon complication of prolonged endotracheal intubation. A 25-year-old woman with severe jaw deformity underwent sagittal split ramus osteotomy under general anesthesia. Two days after extubation, the patient complained of hoarseness, sore throat, and dyspnea. When symptoms persisted, she was evaluated in the Otolaryngology Department. She was diagnosed with laryngeal granuloma of the bilateral arytenoid cartilages, and conservative treatment was selected. Administration of corticosteroid hormones, proton pump inhibitors, and a subsequent follow-up examination performed in our outpatient clinic showed no evidence of recurrence 10 months after the initial presentation.

Micromolar sodium fluoride mediates anti-osteoclastogenesis in Porphyromonas gingivalis-induced alveolar bone loss.

Osteoclasts are bone-specific multinucleated cells generated by the differentiation of monocyte/macrophage lineage precursors. Regulation of osteoclast differentiation is considered an effective therapeutic approach to the treatment of bone-lytic diseases. Periodontitis is an inflammatory disease characterized by extensive bone resorption. In this study, we investigated the effects of sodium fluoride (NaF) on osteoclastogenesis induced by Porphyromonas gingivalis, an important colonizer of the oral cavity that has been implicated in periodontitis. NaF strongly inhibited the P. gingivalis-induced alveolar bone loss. That effect was accompanied by decreased levels of cathepsin K, interleukin (IL)-1ß, matrix metalloproteinase 9 (MMP9), and tartrate-resistant acid phosphatase, which were up-regulated during P. gingivalis-induced osteoclastogenesis. Consistent with the in vivo anti-osteoclastogenic effect, NaF inhibited osteoclast formation caused by the differentiation factor RANKL (receptor activator of nuclear factor κB ligand) and macrophage colony-stimulating factor (M-CSF). The RANKL-stimulated induction of the transcription factor nuclear factor of activated T cells (NFAT) c1 was also abrogated by NaF. Taken together, our data demonstrate that NaF inhibits RANKL-induced osteoclastogenesis by reducing the induction of NFATc1, ultimately leading to the suppressed expression of cathepsin K and MMP9. The in vivo effect of NaF on the inhibition of P. gingivalis-induced osteoclastogenesis strengthens the potential usefulness of NaF for treating periodontal diseases.

Effect of acupuncture on perception threshold: a randomised controlled trial.

OBJECTIVE: To determine the current perception thresholds (CPTs) for arm and mental foramen areas to enable a quantitative evaluation of the effectiveness of acupuncture treatment. METHODS: Ninety-eight volunteers enrolled as participants and were randomly assigned to one of three groups: an acupuncture group (34 subjects); a sham acupuncture group (32 subjects) and a waiting group (32 subjects). CPTs for the arm and mental foramen areas were determined before and after acupuncture at LI4 Hegu of the left hand. A Neurometer CPT was used to evaluate the perception threshold at the homolateral mental foramen and arm. For further exploration, thresholds of homolateral and contralateral mental foramina were determined before and after acupuncture in a subgroup of 13 participants in the acupuncture group. RESULTS: Acupuncture at LI4 increased the perception thresholds of the left mental foramen in the acupuncture group significantly (p<0.01). The increases were significantly greater than in the control group for all frequencies, and significantly greater than sham acupuncture for 250 Hz and 5 Hz. In the subgroup, only the CPTs at 5 Hz increased significantly for the contralateral mental foramen. CONCLUSIONS: Acupuncture at LI4 increases the perception threshold in the mandibular area, but not in the arm. This finding is probably related to the analgesic effect of acupuncture.

Anesthetic management of a child with congenital central hypoventilation syndrome (CCHS, Ondine's curse) for dental treatment.

Congenital Central Hypoventilation Syndrome (CCHS, also known as Ondine's Curse) is a rare syndrome characterized by apnea, cyanosis, and hypotonia. A 4-year-old, 90-cm, 12-kg girl with CCHS, mental retardation (MR), and Hischsprung's disease (HD) was treated under general anesthesia. Intravenous drugs were not used, but sevoflurane, a volatile anesthetic, was used. As a result, the recovery time from the end of the operation to returning to the ward was very short, only 18 minutes. There was no trouble during the perioperative period. We safely performed general anesthesia and dental treatment for a girl who had CCHS with HD and MR.