Osseous Loading by a Volume-Reduced Tongue During Muscle Contractions.

PURPOSE: To investigate how tongue volume reduction affects loads on surrounding bone surfaces produced by neuromuscular stimulation of the tongue. MATERIALS AND METHODS: Of each pair of same-gender minipig siblings, 1 received tongue reduction and 1 underwent sham surgery. Either immediately (acute, 6 pairs) or 1 month (chronic, 5 pairs) after surgery, bone surface and/or suture strains and pressures were recorded from the following locations when the hypoglossal nerve trunk, hypoglossal nerve medial branch, hypoglossal nerve lateral branch, genioglossus, and styloglossus (SG) were electrically stimulated: 1) three rosette strain gauges on the premaxillary palatal surface (premaxilla [PM]) and lingual surfaces of the mandibular alveolus at anterior (mandibular incisor [MI]) and posterior (mandibular molar [MM]) locations; 2) two single-element strain gauges over the palatal surface of the premaxillary-maxillary suture and the lingual surface of the mandibular symphysis; and 3) two pressure transducers on the palatal surface of the maxilla (palatal process) and the lingual surface of the mandibular alveolus (mandibular corpus). RESULTS: Compared with the sham animals in the acute study, reduction animals showed significantly decreased PM and MI strains, as well as palatal process pressure. With muscle contractions, mandibular symphysis and MM strains were enhanced significantly with a more dorsal orientation. In the chronic study, reduction animals showed decreased PM and increased MM strains. On comparison of chronic versus acute studies, PM, MI, and MM strains under SG stimulation were significantly smaller whereas MM strain was significantly larger under hypoglossal nerve trunk, hypoglossal nerve lateral branch, and SG stimulations. CONCLUSIONS: Muscle contractions from a volume-reduced tongue produce lower and higher loads in the anterior and posterior mouth, respectively. However, although the effects on reducing loads in the anterior mouth are persisting over time, compensatory load enhancement in the posterior mouth diminishes owing to surgical healing.

Respiratory internal kinematics of the tongue base and soft palate in obese minipigs with obstructive sleep apnea.

It is largely unknown how the tongue base and soft palate deform to alter the configuration of the oropharyngeal airway during respiration. This study is to address this important gap. After live sleep monitoring of five Yucatan and two Panepinto minipigs to verify obstructive sleep apnea (OSA), eight and four ultrasonic crystals were implanted into the tongue base and soft palate to circumscribe a cubic and square region, respectively. The 3D and 2D deformational changes of the circumscribed regions were measured simultaneously with electromyographic activity of the oropharyngeal muscles during spontaneous respiration under sedated sleep. The results indicated that both obese Yucatan and Panepinto minipigs presented spontaneous OSA, but not in three nonobese Yucatan minipigs. During inspiration, the tongue base showed elongation in both dorsal and ventral regions but thinning and thickening in the anterior and posterior regions, respectively. The widths showed opposite directions, widening in the dorsal but narrowing in the ventral regions. The soft palate expanded in both length and width. Compared to normal controls, obese/OSA ones showed similar directions of deformational changes, but the magnitude of change was two times larger in the tongue base and soft palate, and obese/OSA Panepinto minipigs presented 10 times larger changes in all dimensions of both the tongue base and the soft palate. The distance changes between the dorsal surface of tongue base and soft palate during inspiration increased in normal but decreased in obese OSA minipigs.

Respiratory internal kinematics of the tongue base and soft palate in obese minipigs with obstructive sleep apnea.

It is largely unknown how the tongue base and soft palate deform to alter the configuration of the oropharyngeal airway during respiration. This study is to address this important gap. After live sleep monitoring of 5 Yucatan and 2 Panepinto minipigs to verify obstructive sleep apnea (OSA), 8 and 4 ultrasonic crystals were implanted into the tongue base and soft palate to circumscribe a cubic and square region, respectively. The 3D and 2D dimensional changes of the circumscribed regions were measured simultaneously with electromyographic activity (EMG) of the oropharyngeal muscles during spontaneous respiration under sedated sleep. The results indicated that both obese Yucatan and Panepinto minipigs presented spontaneous OSA, but not in 3 non-obese Yucatan minipigs. During inspiration, the tongue base showed elongation in both dorsal and ventral regions but thinning and thickening in the anterior and posterior regions respectively. The widths showed opposite directions, widening in the dorsal but narrowing in the ventral regions. The soft palate expanded in both length and width. Compared to normal controls, obese/OSA ones showed similar directions of dimensional changes, but the magnitude of change was two times larger in the tongue base and soft palate, and obese/OSA Panepinto minipigs presented 10 times larger changes in all dimensions of both the tongue base and the soft palate. The opposite direction of the respiratory spatial relationship between these two structures was seen in obese/OSA as compared to normal minipigs.

[Oral health and hygiene behavior in chronic renal failure patients].

PURPOSE: To investigate the oral health and hygiene behavior of chronic renal failure(CRF) patients in Shenzhen, so as to provide basis for formulating education for them. METHODS: The history of renal failure, oral health status and oral health care behavior of 336 patients with chronic renal failure(CRF) in the hemodialysis center of Shenzhen Second People's Hospital were investigated by questionnaire and oral examinations. RESULTS: At an average, dialysis was required for 3.2 years. The main cause of renal failure was glomerulonephritis in 49.11% of patients, hypertensive kidney lesion in 19.35% and diabetic nephropathy in 15.77% of patients; 77.8% of them kept brushing teeth two or more than two times every day; 72.9% patients suffered from oral problems such as toothache in recent 12 months. The rate of visiting a dentist when having complaints was 21.7%. CONCLUSIONS: The state of oral health of CRF is worse than the general population of comparable age in China, while their hygiene behavior is better than the corresponding reference general population. However, their consciousness of dental treatment is poor. Therefore, health education for CRF patients should include knowledge about oral diseases complicated with CRF and correct medical philosophy.

Study on the application of oral digital design in aesthetic restoration of anterior teeth of cleft lip/palate patients.

OBJECTIVES: A study was conducted to investigate the clinical effects of oral digital design on the aesthetic restoration of anterior teeth of cleft lip/palate patients. METHODS: Nine adult cleft lip/palate patients who need aesthetic restoration of anterior teeth were recruited. Digital information of patients' dental arches, the surrounding soft tissue and face were captured by digital camera and scanner. The aesthetic analysis and design were conducted using keynote and 3shape software and were demonstrated to the patients. The optimized treatment plan was ensured by communicating with the patients. Digital wax-up models were exported and printed into resin diagnostic models, which were then utilized in the treatment process to guide the doctors and the technicians in tooth preparation and in making the final restorations, respectively. The adhesive procedure was completed after satisfactory try-in. Aesthetics assessment was conducted in accordance with the anterior esthetic evaluation form. The scores of patient's satisfaction were recorded on a questionnaire containing six items of aesthetic index and doctor-patient communication. Patients were interviewed and examined after 1, 3, 6, and 12 months, respectively, and the clinical effects of restorations were evaluated. RESULTS: All nine patients had satisfactory clinical results. The aesthetic defects of the patients were effectively addressed. All treatments met the requirements of the preoperative digital designs. The patients' scores were all above 90 on the satisfaction scale. At 12 months after the operation, the clinical effects of restorations of all cases achieved A class in each evaluation indicator. CONCLUSIONS: For cleft lip/palate patients with esthetic defect in the anterior teeth, the digital design plays an important role in optimizing the treatment plan and guides the whole treatment process. This design can help clinicians achieve predictable satisfactory aesthetic results.

Obstructive sleep apnea in obese minipigs.

OBJECTIVE: Obesity has reached epidemic proportions and is a strong risk factor for obstructive sleep apnea (OSA). However, the underlying mechanisms are poorly understood and current treatment strategies for OSA and obesity have critical limitations. Thus, establishment of an obesity-related large animal model with spontaneous OSA is imperative. MATERIALS AND METHODS: Natural and sedated sleep were monitored and characterized in 4 obese (body mass index - BMI>48) and 3 non-obese (BMI<40) minipigs. These minipigs were instrumented with the BioRadio system under sedation for the wireless recording of respiratory airflow, snoring, abdominal and chest respiratory movements, electroencephalogram, electrooclulogram, electromyogram, and oxygen saturation. After instrumentation, the minipigs were placed in a dark room with a remote night-vision camera for monitoring all behaviors. Wakefulness and different sleep stages were classified, and episodes of apneas and/or hypopneas were identified during natural and/or sedated sleep. RESULTS: No hypopnea episodes were observed in two of the non-obese minipigs, but one non-obese minipig had 5 hypopnea events. Heavy snoring and 27-58 apnea and/or hypopnea episodes were identified in all 4 obese minipigs. Most of these episodes occurred in the rapid eye movement stage during natural sleep and/or sedated sleep in Yucatan minipigs. CONCLUSIONS: Obese minipigs can experience naturally occurring OSA, thus are an ideal large animal model for obese-related OSA studies.