Obesity is now a global epidemic. Obese people are at higher risk of snoring. Weight reduction could influence the prevalence of snoring. Present study tried to find out, whether weight reduction is of benefit in all adult snorers.
Materials and Methods:
It is a cross sectional study, on 349 subjects (196 males and 153 females). They and their spouses were asked for snoring habits. Their neck circumference, height and weight was measured and Body mass index (BMI) was calculated, and they were classified into low normal, high normal, pre-obese and obese BMI groups. Prevalence rates of snoring in different groups were compared, to find out any statistically significant difference, between them.
Statistically significant difference, in prevalence rates of snoring was found, when obese and pre-obese group were compared with normal BMI group, separately. No significant difference was found in prevalence rates, when comparison was made between obese and pre-obese group. Difference in prevalence of snoring, was also not significant, when comparison was made between low normal and high normal BMI groups. Neck circumference of snorers was significantly more than the neck circumference of non-snorers in all BMI groups. Gender wise difference, in prevalence of snoring was also not significant.
Body mass index target needs to be set at 25 kg/m2, in weight reduction programmes, to achieve clinically relevant response in a snorer. There is no need to put extra emphasis, on further reduction of BMI. Weight reduction, is not helpful in all adult snorers, especially those with normal BMI, where other causes of snoring, like fat around upper airways, need to be considered.
Adult; body mass index; obesity; snoring; weight reduction
Cephalometry is often used to assess patients with sleep apnoea but whether these measurements differ from those in non-apnoeic snorers and how they are influenced by age is not clear. Cephalometric radiographs of patients with sleep apnoea were compared with those of snorers without sleep apnoea and those of non-snorers. Fifty two snorers with suspected sleep apnoea had a conventional sleep study and were divided into two groups: those with an apnoea-hypopnoea index greater than 10/h (n = 40, sleep apnoea group) and those whose apnoea-hypopnoea index was 10/h or less (n = 12, snorer group). The cephalometric measurements in these patients were compared with those of 34 non-snoring control subjects. Controls were subdivided into two groups: control group 1 included 17 subjects similar in age to the sleep apnoea and snorer groups (mean (SD) age 50.0 (10.9), 50.7 (9.4), and 50.6 (9.7) years); control group 2 included 15 young men (25.4 (2.6) years). The distance from the mandibular plane to the hyoid bone (MP-H) and the length of the soft palate were greater in the patients with sleep apnoea (28.7 (7.8) and 43.6 (5.0) mm) than in the snorers (23.7 (4.2) and 40.3 (4.9 mm). The MP-H was similar in snorers and age matched control subjects, but was significantly greater in the older than in the younger control subjects (22.1 (6.1) vs 17.0 (6.8]. The soft palate was longer in subjects who snored (both sleep apnoea patients and snorers) than in control subjects. The MP-H distance significantly correlated with age for all subjects (snorers and controls) and for the control subjects alone. This study shows that non-apnoeic snorers have cephalometric abnormalities that differ from those of patients with sleep apnoea and that cephalometric values are influenced by the subject's age.
In a study conducted in four family practice units in Toronto, Canada, 2001 subjects reported on snoring and medical conditions in members of their households. For spouses the prevalence of snoring increased with age up to the seventh decade, with a higher prevalence of nearly 85% in husbands. For 11 medical problems an association existed between snoring, its frequency, and the presence of the condition. This association continued when the data were corrected for sex, age, and marital state. For hypertension both men and women who snored between the fifth and 10th decades had a twofold increase over non-snorers. The prevalence of heart disease and other conditions, except for diabetes and asthma, also increased in snorers in this age group. When corrected for smoking and obesity the association between snoring, hypertension, and heart disease persisted. These findings extend those of Lugaresi et al, and if they could be confirmed snoring as a risk factor for conditions other than sleep apnoea and sleep disorders might be considered. Methods of alleviating the acoustic annoyance of snoring may also provide direct medical benefits.
Obstructive sleep apnea (OSA) may increase perioperative complications. The aim of this study was to determine the relationship among postoperative pulmonary complication, snoring and STOP questionnaire in patients with ortophaedic surgery.
1,406 consecutive records of patients who had undergone elective ortophaedic surgery during the period January 2005-December 2008 were investigated retrospectively. Demographic information, sleep symptoms, STOP questionnaire, comorbidities and outcome data were collected.
There were 289 (20.5%) snorers and 1,117 (79.5%) non-snorers in the study group. There was no significant difference between snorer and non-snorer patients (p > 0.05) in the prevalence of pneumonia and respiratory failure. But in snorer patients the rate of postoperative atelectasis was significantly higher than in non-snorer group (p < 0.0001). The STOP Questionnaire was given to 1,406 patients and 147 (10.4%) out of them were classified at high risk of OSA. There was no significant difference in the prevalence of pneumonia and respiratory failure between low and high risk group (p > 0.05). However, in high risk patients the occurrence of postoperative atelectasis was significantly higher than in low risk group (p < 0.0001).
Postoperative atelectasis was significantly more prevalent in the high risk group according to STOP questionnaire.
Atelectasis; Obesity; Orthopedic surgery; Sleep apnea; STOP questionnaire
The association of snoring with ischaemic heart disease and stroke was studied prospectively in 4388 men aged 40-69. The men were asked, in a questionnaire sent to them, whether they snored habitually, frequently, occasionally, or never. Hospital records and death certificates were checked for the next three years to establish how many of the men developed ischaemic heart disease or stroke: the numbers were 149 and 42, respectively. Three categories of snoring were used for analysis: habitual and frequent snorers (n = 1294), occasional snorers (n = 2614), and non-snorers (n = 480). The age adjusted relative risk of ischaemic heart disease between habitual plus frequent snorers and non-snorers was 1.91 (p less than 0.01) and for ischaemic heart disease or stroke, or both, 2.38 (p less than 0.001). There were no cases of stroke among the non-snorers. Adjustment for age, body mass index, history of hypertension, smoking, and alcohol use did not significantly decrease the relative risks, which were 1.71 (p greater than 0.05) for ischaemic heart disease and 2.08 (p less than 0.01) for ischaemic heart disease and stroke combined. At the beginning of follow up in 1981, 462 men reported a history of angina pectoris or myocardial infarction. For them the relative risk of ischaemic heart disease between habitual plus frequent snorers and non-snorers was 1.30 (NS); for men without previous ischaemic heart disease 2.72 (p less than 0.05). Snoring seems to be a potential determinant of risk of ischaemic heart disease and stroke.
We hypothesized that sympathetic nervous system activity (SNSA) is increased and parasympathetic nervous system activity (PNSA) is decreased during non-rapid eye movement (NREM) sleep in non-apneic, otherwise healthy, snoring individuals compared to control. Moreover, we hypothesized that these alterations in snoring individuals would be more evident during non-snoring than snoring when compared to control.
To test these hypotheses, heart rate variability was used to measure PNSA and SNSA in 11 normotensive non-apneic snorers and 12 control subjects before and 7-days after adapting to nasal continuous positive airway pressure (nCPAP).
Our results showed that SNSA was increased and PNSA was decreased in non-apneic snorers during NREM compared to control. However, these changes were only evident during the study in which snoring was eliminated with nCPAP. Conversely, during periods of snoring SNSA and PNSA were similar to measures obtained from the control group. Additionally, within the control group, SNSA and PNSA did not vary before and after nCPAP application.
Our findings suggest that long-lasting alterations in autonomic function may exist in snoring subjects that are otherwise healthy. Moreover, we speculate that because of competing inputs (i.e. inhibitory versus excitatory inputs) to the autonomic nervous system during snoring, the full impact of snoring on autonomic function is most evident during non-snoring periods.
To compare the Cone-Beam Computerized Tomography (CBCT) scan measurements between patients with Obstructive Sleep Apnea (OSA) and snorers to develop a prediction model for OSA based on CBCT imaging and the Berlin Questionnaire.
Materials and methods
80 subjects (46 OSA patients with Apnea-Hypoapnea Index [AHI]≥ 10 and 34 snorers AHI<10 based on ambulatory somnographic assessment) were recruited through flyers and mail at USC School of Dentistry and at a private practice. Each patient answered the Berlin Questionnaire, and was imaged with CBCT in supine position. Linear and volumetric measurements of the upper airway were performed by one blinded operator and multivariate logistic regression analysis was used to identify risk factors for OSA.
OSA patients were predominantly male, older, had a larger neck size and larger Body Mass index than the snorers. The minimum cross-sectional area of the upper airway and its lateral dimension were significantly smaller in the cases. Airway uniformity defined as the minimum cross-sectional area divided by the average area was significantly smaller in the OSA patients.
Age>57 years, male gender, a “high risk” Berlin Questionnaire and narrow upper airway lateral dimension (<17mm) were identified as significant risk factors for OSA. The results of this study indicate that 3-dimensional CBCT airway analysis could be used as a tool to assess the presence and severity of OSA. The presence and severity (as measured by the RDI) of OSA is associated with a narrow lateral dimension of the airway, increasing age, male gender, and the Berlin questionnaire.
Cone-Beam Computerized Tomography; Obstructive sleep apnea; Upper airway; Volume
To estimate the prevalence of sleep abnormalities and their association with glucose intolerance and metabolic syndrome (MS) in the normal-weight urban South Indian population.
This population-based, cross-sectional study was carried out in 358 subjects aged 20–76 years randomly selected from the Chennai Urban Rural Epidemiology Study in South India. A validated questionnaire assessing various sleep abnormalities (snoring, daytime sleepiness, lack of refreshing sleep, and number of hours of sleep) was administered. All subjects underwent an oral glucose tolerance test, and anthropometric biochemical measurements were obtained to assess cardiometabolic risk factors including glucose intolerance. Diabetes risk was assessed using a previously validated Indian Diabetes Risk Score (IDRS).
The overall prevalence of snoring and daytime sleepiness was 40% and 59%, respectively. Snorers were more male, older, smokers, and had higher levels of cardiometabolic risk factors. Subjects with daytime sleepiness had higher body mass index (BMI) and abdominal obesity. Both snoring (50.9% vs 30.2%, p < 0.001) and daytime sleepiness (68% vs 49.7%, p < 0.001) were more prevalent among subjects with impaired glucose metabolism compared to those with normal glucose metabolism. Both sleep measures were associated with higher diabetes risk scores, as assessed by the IDRS (snoring: trend χ2, 11.14, p = 0.001; daytime sleepiness: trend χ2, 5.12, p = 0.024). Metabolic syndrome was significantly associated with snoring even after adjusting for age, sex, family history of diabetes, physical activity, smoking, and alcohol.
The prevalence of snoring and daytime sleepiness is high among urban South Indians and these two sleep measures are associated with glucose intolerance, MS, and higher diabetes risk scores.
sleep abnormalities; snoring; daytime sleepiness; cardiometabolic risk factors; metabolic syndrome; Asian Indians
BACKGROUND: Snoring and obstructive sleep apnoea (OSA) are worse or may only occur in the supine position. The effect of body position on upper airway size has been reported, but the effect on tongue posture has not previously been examined. METHODS: Detailed measurements were made of tongue posture from upright and supine lateral cephalograms on 24 men with OSA and 13 men with non-apnoeic snoring matched for age, body mass index, and craniofacial skeletal pattern. Patients with OSA had apnoea/hypopnoea indices (AHI) of > 50/hour and/or apnoea indices (AI) of > 25/hour while non-apnoeic snorers had AHI of < 10/hour and AI of < 5/hour. RESULTS: In non-apnoeic snorers the tongue depth measurements for the superior-posterior portion of the tongue were larger in the supine than in the upright position (p < 0.05). There was no significant difference in tongue depth measurements between the upright and the supine position in the patients with OSA. CONCLUSIONS: When awake patients with OSA move from the upright to the supine position they maintain their upright tongue posture which may tend to protect against upper airway collapse secondary to the increased gravitational load on the tongue. In contrast, when awake non-apnoeic snorers move from the upright to the supine position a significant dorsal movement in the superior-posterior portion of the tongue is observed.
To clarify whether persistent snoring in 2- to 3-year-olds is associated with behavioral and cognitive development, and to identify predictors of transient and persistent snoring.
Two hundred forty-nine mother/child pairs participated in a prospective birth cohort study. Based upon parental report of loud snoring ≥2 times weekly at 2 and 3 years of age, children were designated as nonsnorers, transient snorers (snored at 2 or 3 years of age, but not both), or persistent snorers (snored at both ages). We compared groups by using validated measures of behavioral and cognitive functioning. Potential predictors of snoring included child race and gender, socioeconomic status (parent education and income), birth weight, prenatal tobacco exposure (maternal serum cotinine), childhood tobacco exposure (serum cotinine), history and duration of breast milk feeding, and body mass relative to norms.
In multivariable analyses, persistent snorers had significantly higher reported overall behavior problems, particularly hyperactivity, depression, and inattention. Nonsnorers had significantly stronger cognitive development than transient and persistent snorers in unadjusted analyses, but not after demographic adjustment. The strongest predictors of the presence and persistence of snoring were lower socioeconomic status and the absence or shorter duration of breast milk feeding. Secondary analyses suggested that race may modify the association of childhood tobacco smoke exposure and snoring.
Persistent, loud snoring was associated with higher rates of problem behaviors. These results support routine screening and tracking of snoring, especially in children from low socioeconomic backgrounds; referral for follow-up care of persistent snoring in young children; and encouragement and facilitation of infant breastfeeding.
sleep-disordered breathing; behavior problems; preschool; environmental tobacco smoke; breastfeeding; overweight
Methods: We evaluated an intranasal corticosteroid, fluticasone propionate, in 24 consecutive snorers with associated rhinitis using a randomised, placebo controlled, crossover design. Patients underwent polysomnography, snoring noise, and NAR measurements at baseline and after each 4 week treatment period.
Results: Twenty three patients completed the protocol and were divided into an apnoeic group (group A; 13 patients) and a non-apnoeic snoring group (group S; 10 patients) based on an apnoea-hypopnoea frequency (AHI) of ⩾10/h or <10/h. AHI was significantly lower following treatment with fluticasone than with placebo in the total population (median (quartile range) 11.9 (22.6) v 20 (26.3); p<0.05) and in group A (23.3 (21.3) v 30.3 (31.9); p<0.05). Median (95% confidence interval) within subject differences for AHI were -3.2 (-17.7 to -0.2) in the total population and -6.5 (-29.5 to 1.8) in group A. NAR was also lower on fluticasone (2.74 (1.21) v 3.27 (1.38), p<0.01), within subject difference being -0.45 (95% CI -0.87 to -0.21). The changes in AHI and NAR in group A were significantly correlated (r = 0.56; p<0.05). Snoring noise and sleep quality were unchanged but daily diary records indicated subjective improvements in nasal congestion and daytime alertness with fluticasone (p<0.02).
Conclusions: Intranasal fluticasone is of benefit to some patients with OSAS and rhinitis. The data suggest that this form of nasal obstruction may contribute to the pathophysiology of OSAS.
We have previously reported that bedtime ethanol (2.0 ml/kg of 100 proof vodka) increases upper airway closing pressure in males who habitually snored but were otherwise healthy. We also observed that some of these snorers developed obstructive apneas. To explore this phenomenon in more detail, we measured the inspiratory resistance (R1) and respiratory drive after bedtime ethanol in 10 nonobese men (ages 23 to 33) with no history of snoring. Subjects went to bed wearing a tightly fitting valved mask over the nose and mouth that allowed measurement of inspiratory and expiratory flow, pressure in the mask, and endtidal CO2. We measured R1 by calculating the pressure difference between the mouth and a balloon positioned in the midesophagus. Respiratory drive was quantified by the inspiratory occlusion pressure (P0.1), the ventilatory response to hyperoxic hypercapnia (ΔV̇E/ΔPETCO2), and the ventilatory response to isocapnic hypoxia (ΔV̇E/ΔSaO2). Measurements were made during waking and during stage 2 NREM sleep on two nights: (1) when the subjects drank 1.5 ml/kg of 100 proof vodka in orange juice over a 30-min period 15-45 min before lights out and (2) when the orange juice contained less than 0.1 ml of vodka floating on the top. Eight of the nine men in whom we had technically adequate measurements showed a rise in R1 during NREM sleep above the waking level on both control and ethanol nights and the sleeping R1 was greater on the ethanol than on the control night. There was a tendency for P0.1 to be higher during sleep and greater on the ethanol night, suggesting that the neural output to the respiratory muscles was not depressed and may have been stimulated by the inspiratory “loading” secondary to the increased R1. The hypercapnic response was significantly depressed during sleep. Whereas the response tended to be less on the ethanol than on the control night, the difference was not significant. The hypoxic response showed little change from waking to sleeping and no significant change with ethanol. We speculate that inspiratory loading due to increased upper airway resistance tends to stimulate respiratory drive and thereby partially offsets the depressant effect of ethanol on the central respiratory chemoreceptors.
Ethanol; Respiratory Drive; Sleep; Upper Airway Resistance
Nasal continuous positive airway pressure (nasal CPAP) and polysomnography were used to analyze the time course of the effect of bedtime ethanol on resistance of upper airways and on the number of respiratory pauses during sleep. On one night, six asymptomatic nonalcoholic male snorers drank 2 ml/kg of 100 proof vodka mixed in orange juice (ethanol dose, 0.79 gm/kg, giving a peak blood alcohol level of 71.8 ± 33.3 mg/dl). On a second night they received a placebo (1–2 drops of vodka floated on top of the orange juice). We measured (a) the minimum nasal CPAP required to eliminate snoring, (b) the number of hypopneas and apneas during each hour of sleep and (c) the arterial oxygen saturation (SaO2) by ear oximetry. On the alcohol night there was a significant increase in the CPAP pressure required to eliminate snoring (placebo 4.8 ± 1.7 cm H2O, alcohol 6.2 ± 1.5 cm H2O). The number of respiratory events per hour of sleep (apnea index) was 7.5 ± 2.1 for ethanol nights versus 3.8 ± 2.7 for placebo nights (p < 0.0125). An apnea index of greater than 5 is generally considered abnormal. There was no significant difference in the number of desaturation events (declines of 4% or more in the SaO2) or in the mean SaO2, but the minimum SaO2 was significantly lower on the ethanol night (placebo 89.8% ± 1.6, alcohol 86.8% ± 2.7, p < 0.05). The effect of this dose of alcohol on airway resistance was most pronounced during the first 2 hr after ingestion.
The aim of this study was to determine if snorers have a narrower oropharyngeal airway area because of fat infiltration, and an elevated body mass index.
Materials and Methods
Ten control subjects and 19 patients that snored were evaluated. We obtained 2-mm-thick axial CT scan images every 0.6 seconds during expiration and inspiration at the same level of the oropharynx. We selected the largest and the smallest oropharyngeal airway areas and found the differences. From the slice that had the smallest oropharyngeal airway area, the thickness of the parapharyngeal and subcutaneous fat was measured. The measurements from the left and right side were added together and single values for parapharyngeal and subcutaneous fat tissue thickness were then found.
The conventional measure of body mass index was significantly higher in the snorers (p < 0.05). The difference in the smallest oropharyngeal airway area between snorers and the controls was statistically significant (p < 0.01). The average difference between the largest and the smallest oropharyngeal area in the control group and the snorer group was statistically significant (p < 0.05). There was no significant difference in the largest oropharyngeal airway area, the total subcutaneous fat width and the total parapharyngeal fat width between snorers and control subjects (p > 0.05).
We concluded that the oropharyngeal fat deposition in snorers is not an important factor, and it does not predispose a person to the upper airway narrowing.
Computed tomography (CT); Computed tomography (CT), functional imaging; Neek, CT; Neck, anatomy
Reproduction of anatomical structures by rapid prototyping has proven to be a valid adjunct for craniofacial surgery, providing alternative methods to produce prostheses and development of surgical guides. The aim of this study was to introduce a methodology to fabricate asymmetric human mandibles by rapid prototyping to be used in future studies for evaluating mandibular symmetries. Stereolithic models of human mandibles were produced with varying amounts of asymmetry in the condylar neck, ramus and body of the mandible by means of rapid prototyping. A method for production of the synthetic mandibles was defined. Model preparation, landmark description and development of the experimental model were described. A series of synthetic mandibles ranging in asymmetry were accurately produced from a scanned human mandible. A method for creating the asymmetries, fabricating, coating and landmarking the synthetic mandibles was formulated. A description for designing a reproducible experimental model for image acquisition was also outlined. Production of synthetic mandibles by stereolithic modeling is a viable method for creating skeletal experimental models with known amounts of asymmetry.
Biomedical engineering; Rapid prototyping; Image processing; Stereolithic mandible models.
Snorers represent a heterogenous group that require adequate assessment before recommending surgical treatment. There are unfortunately no specific features either in the history or physical examination that might predict those chronic snorers with obstructive sleep apnoea. We have used trained observation together with pulse oximetry ('sleep screening') and fibreoptic nasendoscopy with Muller manoeuvre in our unit to assess snorers. This combination is a reliable means of distinguishing apnoeic patients from simple snorers and determining the level of the obstructing segment. We report our experience in using these methods in the management of 71 chronic snorers. We stress the value of conservative management, and emphasize that obesity, habitual alcohol ingestion and nasal obstruction should be corrected before embarking on pharyngeal surgery.
BACKGROUND: The obstructive sleep apnoea syndrome is characterised by an increased apnoea-hypopnoea index and a reduction in the minimal arterial oxygen saturation (SaO2) values during sleep. The extent to which these variables can be predicted by cephalometric and otorhinolaryngological variables was tested. METHODS: One hundred consecutive habitual snorers (84% male), with a mean (SD) age of 50.1 (10.1) years, were studied. The 45 patients with less severe sleep apnoea, with an apnoea-hypopnoea index of 10 or less (group A), were compared with the 55 with an index above 10 (group B). RESULTS: Body mass index, some cephalometric variables, and some otorhinolaryngological variables differed significantly between group A and group B, in particular the soft tissue measures PNS-P (posterior nasal spine to palate), MP-H (mandibular plane to hyoid bone), degree of oropharynx stenosis, and tongue size. In a multiple regression correlation analysis MP-H, SNB (angle from sella to nasion to subspinale point), SNA (angle from sella to nasion to supramentale point), PAS (posterior airway space), tongue size, and body mass index contributed significantly to the equation explaining the severity of sleep apnoea. Nevertheless, these variables together explained only 33% of the variance of the apnoea-hypopnoea index in the total sample; they were more important for patients with moderate to severe stages of the disease. CONCLUSION: The lack of association between cephalometric variables and mild sleep apnoea suggests that the differences in these variables (soft tissue measures) may be the consequence rather than the cause of habitual snoring and the obstructive sleep apnoea syndrome.
OBJECTIVE--To investigate the relation between snoring and various respiratory symptoms and passive parental smoking. DESIGN--Data were collected by questionnaire. SETTING--Primary schools in Guardiagrele and Francavilla in the Abruzzi region in central Italy. SUBJECTS--1615 Children aged 6-13 years were categorised according to whether they snored often; occasionally apart from with colds; only with colds; or never. RESULTS--118 Children were habitual snorers and 137 were reported to snore apart from when they had colds. Never snorers (n = 822) were significantly older than children in other categories. Snoring was significantly associated with rhinitis, production of cough and sputum, previous tonsillectomy, and passive parental smoking. Of the habitual snorers, 82 were exposed to passive smoking. The prevalence of habitual snoring increased significantly with the number of cigarettes smoked by parents (from 5.5% in never smoking [corrected] households to 8.8% in heavy smoking households). CONCLUSIONS--Snoring is quite common in children. The dose-effect relation of smoking and snoring shown in this study adds weight to a further adverse effect of parental smoking on children's health.
Accurate measurement of the height and buccolingual thickness of available bone has a significant role in dental implantology. The shadow of ramus on the mandibular second molar region disturbs the sharpness of conventional tomographic images. The aim of this study was to evaluate the effect of transferring the shadow of ramus from the center of the focal plane, by changing the position of mandible, on the sharpness of the posterior mandibular region.
Materials and Methods:
In this experimental study, we used 10 dry human mandibles. Three metal balls were mounted on the midline and mandibular second molar regions bilaterally. Standard panoramic and tomographic images were taken. Then, the mandible was tilted buccaly for 8° – compensating the normal lingual inclination of the mandibular ridge and teeth on this region – and tomographic images were taken again. The height and thickness of bone were measured on the images and then compared with the real amounts measured directly on mandibles. Also, the sharpness of mandibular canals was compared between the two tomographic methods. Findings were analyzed with repeated measured ANOVA test (P<0.05).
The height of mandibular bone, on the images of the tilted tomography technique was more accurate compared to standard (P<0.001), but standard tomography had more accuracy in estimating the buccolingual thickness at the half-height point. Regarding the sharpness of mandibular canals, we found no significant differences between two tomographic methods.
Buccal tilting is recommended when measuring the bone height is more important, but routine standard tomography is preferred when the thickness is requested.
Buccal tilt; mandible; positioning; spiral tomography
The ability of irradiated tissue to support bony growth remains poorly defined, although there are anecdotal cases reported showing mixed results for the use of mandibular distraction osteogenesis after radiation for head and neck cancer. Many of these reports lack objective measures that would allow adequate analysis of outcomes or efficacy. The purpose of this experiment was to utilize a rat model of mandibular distraction osteogenesis after high dose and highly fractionated radiation therapy and to evaluate and quantify distracted bone formation under these conditions. Male Sprague–Dawley rats underwent 12 fractions of external beam radiation (48 Gray) of the left mandible. Following a two week recovery period, an external frame distractor was applied and gradual distraction of the mandible was performed. Tissue was harvested after a twenty-eight day consolidation period. Gross, radiologic and histological evaluations were undertaken. Those animals subjected to pre-operative radiation showed severe attenuation of bone formation including bone atrophy, incomplete bridging of the distraction gap, and gross bony defects or non-union. Although physical lengthening was achieved, the irradiated bone consistently demonstrated marked damaging effects on the normal process of distraction osteogenesis. This murine model has provided reliable evidence of the injurious effects of high dose radiation on bone repair and regeneration in distraction osteogenesis utilizing accurate and reproducible metrics. These results can now be used to assist in the development of therapies directed at mitigating the adverse consequences of radiation on the regeneration of bone and to optimize distraction osteogenesis so it can be successfully applied to post-oncologic reconstruction.
The identification of skeletal remains is of paramount importance in medico-legal investigations. The skeletal components most often investigated for gender determination are the pelvis and skull, with the mandible being a practical element to analyze sexual dimorphism in the fragmented bones. Presence of a dense layer of compact bone makes it very durable and well preserved than many other bones. Mandibular ramus can be used to differentiate between sexes and it also expresses strong univariate sexual dimorphism. When skeleton sex determination is considered, metric analyses on the radiographs are often found to be of superior value owing to their objectivity, accuracy, and reproducibility.
Aims and Objectives:
(1) To measure, compare, and evaluate the various measurements of mandibular ramus as observed on orthopantomographs. (2) To assess the usefulness of mandibular ramus as an aid in sex determination.
Materials and Methods:
A retrospective study was conducted using orthopantomographs of 50 males and 50 females, which were taken using Kodak 8000C Digital Panoramic and Cephalometric System (73 kVp, 12 mA, 13.9 s). Mandibular ramus measurements were carried out using Master View 3.0 software. The measurements of the mandibular ramus were subjected to discriminant function analysis.
We observed each variable of the mandibular ramus to be a significant predictor in classifying a given sample (P < 0.001).
This study on mandibular ramus measurements using orthopantomograph shows strong evidence suggesting that the ramus can be used for gender determination for forensic analysis.
Discriminant function analysis; mandibular ramus; orthopantomograph; sexual dimorphism
The purpose of this investigation was to determine if the mechanical environment of the mandible is changed by osteotomy and fixation, as assessed by the measurement of bone strain on the condylar neck and mandibular corpus.
Materials and Methods
Immediately following unilateral mandibular osteotomy and distractor placement, strain gauges were attached directly to the corpus and condylar neck in a sample of domestic pigs. Bone strains were recorded during mastication and muscle stimulation. Comparisons of principal strain magnitudes and orientations were made between sides and between the osteotomy sample and a control database.
The animals preferred to chew on the non-osteotomy side. Corpus strains were higher for osteotomy-side chewing but were comparable to the control database, regardless of chewing side. For the condyle, compared to the control database and the non-osteotomy side, the osteotomy side was underloaded in compression. Furthermore, the orientation of compressive strain was highly variable and more horizontally oriented than that of control and non-osteotomy condyles. Stimulation of the masseter and medial pterygoid loaded the mandible to normal levels.
Masticatory behavior was altered, probably as a combined result of disruption to the occlusion, changes in muscle recruitment, and probable loss of sensory feedback. However, neither these changes nor damage to the muscles explain the decrease and reorientation of compressive strain on the condylar neck. Alternatively, the modified strain pattern could have arisen from positional instability of the proximal bone fragment.
condyle; mandible; bone strain; distraction osteogenesis; pig
Most patients with obstructive sleep apnoea (OSA) can restore airflow after an obstructive respiratory event without arousal at least some of the time. The mechanisms that enable this ventilatory recovery are unclear but probably include increased upper airway dilator muscle activity and/or changes in respiratory timing. The aims of this study were to compare the ability to recover ventilation and the mechanisms of compensation following a sudden reduction of continuous positive airway pressure (CPAP) in subjects with and without OSA.
Ten obese patients with OSA (mean (SD) apnoea‐hypopnoea index 62.6 (12.4) events/h) and 15 healthy non‐obese non‐snorers were instrumented with intramuscular genioglossus electrodes and a mask/pneumotachograph which was connected to a modified CPAP device that could deliver either continuous positive or negative pressure. During stable non‐rapid eye movement sleep the CPAP was repeatedly reduced 2–10 cm H2O below the level required to eliminate flow limitation and was held at this level for 5 min or until arousal from sleep occurred.
During reduced CPAP the increases in genioglossus activity (311.5 (49.4)% of baseline in subjects with OSA and 315.4 (76.2)% of baseline in non‐snorers, p = 0.9) and duty cycle (123.8 (3.9)% of baseline in subjects with OSA and 118.2 (2.8)% of baseline in non‐snorers, p = 0.4) were similar in both groups, yet patients with OSA could restore ventilation without cortical arousal less often than non‐snorers (54.1% vs 65.7% of pressure drops, p = 0.04). When ventilatory recovery did not occur, genioglossus muscle and respiratory timing changes still occurred but these did not yield adequate pharyngeal patency/ventilation.
Compensatory mechanisms (increased genioglossus muscle activity and/or duty cycle) often restore ventilation during sleep but may be less effective in obese patients with OSA than in non‐snorers.
OSAS is the most common and best-recognized form of SRBD. Effective treatment is available with CPAP being the treatment of choice, once the essential nonspecific measures of excluding endocrine and other treatable causes, including weight loss and avoiding sedative agents have been undertaken. The expense of CPAP apparatus and the need to use this for prolonged period may prompt some patients to evaluate other sub-optimal options. Surgical treatment will continue to be a gamble or a treatment of last resort. Whatever plan is developed, it is important that the patient be reassessed after six months and then by annual PSGs.
The potential population of snorer / apneic patients is so wide and the cost of the proper care so high that the field is ripe for abuses. The confusion between symptoms of snoring and the incidence of SRBD has compounded this proliferation. Cut-rate care that cuts corners is often more expensive in the long run. Interested readers should be aware of the potential inappropriate applications of surgical treatment, especially LAUP, and be alerted to the best medical interests of their patients.
Orthopantomography (panoramic radiography) has been used for the study of measurements involving particularly the prediction of the eruption of impacted lower third molars and analyses of measurements of the ramus and head of mandible. The discrepancies involved with the projection of this radiographic image has stimulated the search for further ways to use it, particularly in orthodontic treatments and oral and maxillofacial surgeries. The author proposes a graphimetric method for the mandible, based on panoramic radiography. The results are expressed in linear and angular measurements, aiming at bilateral comparisons as well as the determination of the proportion of skeletal and dental structures, individually and among themselves as a whole. The method has been named Panorametry, and allows measurement of the mandible (Mandibular Panorametry) or the posterior mandibular teeth (Dental Panorametry). When combining mandible and maxilla, it should be referred to as Total Panorametry. It may also be used, in the future, with Cone Beam computed tomography (CT) images, and in this case it may be mentioned as CT Panorametry.