Controlled, prospective trial of psychosocial function before and after mandibular advancement splint therapy.

INTRODUCTION: The aim of the study was to investigate psychosocial function in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS), before and after mandibular advancement splint (MAS) therapy. METHODS: In a prospective, parallel-group study, changes in psychosocial scores were compared before and after MAS therapy for OSAHS. Patients from the top (MAS treated, n = 40) or bottom (conservatively treated n = 35) of a MAS waiting list rated quality of life (Short Form 36 [SF-36] Health Survey) and sleepiness (Epworth Sleepiness Scale [ESS]). Both groups' ratings at baseline were completed while on conservative therapy. RESULTS: Baseline variables did not differ between groups. At follow-up, psychosocial scores showed improvement in MAS-treated patients, with odds ratios (confidence interval) of 0.26 (0.09, 0.75) and 0.36 (0.14, 0.92) for sleepiness and energy/vitality domain, respectively. Statistically significant improvement in the median (range) sleepiness score (10 [1 to 18] to 6 [1 to 14]; P <0.001) and energy/vitality domain (18 [7 to 20] to 19 [14 to 20]; P = 0.03) were observed with MAS therapy. Reductions were detected in median apnea-hypopnea index (median [range] 16 [5.2 to 30] to 4.6 [0.8 to 17.2] events/hour; P <0.001), and oxygen desaturation index (ODI) (11 [3 to 16] to 0 [0 to 5] events/hour; P <0.001) at follow-up with MAS therapy. Similar changes were observed in the comparison group when they went on to be treated with MAS. CONCLUSIONS: This study demonstrated that treatment with MAS produced statistically and clinically significant psychosocial and cardio-respiratory improvements.

The use of videofluoroscopy in the assessment of the pharyngeal airway in obstructive sleep apnoea.

This prospective cohort study evaluated the use of videofluoroscopy in assessing changes in both antero-posterior (A-P) and transverse pharyngeal airway dimensions in patients with obstructive sleep apnoea (OSA). Forty patients [32 males and 8 females; mean age of 49.3 (SD = 10.79) years] with confirmed OSA, referred for mandibular advancement appliance (MAA) therapy were recruited. Patients received a customized Herbst MAA, adjusted for maximum comfortable protrusion. A standard lateral cephalogram, supine A-P, and transverse videofluoroscopic investigations were performed. Repeat supine videofluoroscopic investigations were undertaken with the MAA in situ. Parametric tests were used to evaluate the study hypotheses as the data were normally distributed. A paired t-test was employed to determine both the impact of posture on the airway using upright cephalometry and supine videofluoroscopy and the effect of MAA insertion on A-P and transverse pharyngeal airway dimensions. Following a change in posture from upright to supine, highly statistically significant (P < 0.001) changes were observed for all lateral pharyngeal dimensions. Statistically significant increases in minimum lingual airway (P < 0.001) and maximum transverse pharyngeal airway (P < 0.001) were found following MAA insertion. A reduction in soft palate area (P = 0.029) and pharyngeal height (P < 0.001) was also noted. Videofluoroscopy offers a useful dynamic assessment of the pharyngeal airway in both the A-P and transverse planes in patients with OSA.

Influence of supplemental written information on adolescent anxiety, motivation and compliance in early orthodontic treatment.

OBJECTIVES: To test the null hypotheses that supplementation of verbal information with written information when obtaining consent to orthodontic treatment has no effect on (1) anxiety, motivation and apprehension related to treatment and (2) compliance in the early stages of fixed appliance therapy. MATERIALS AND METHODS: Seventy-six adolescents who were due to start fixed appliance therapy were randomly allocated to receive verbal information only or verbal and written information before orthodontic treatment. Participants' anxiety, motivation, and apprehension were assessed using a questionnaire that was completed prior to meeting the orthodontic clinician (T1), following consent to treatment (T2), and after 12 weeks of treatment (T3). Appointment attendance, appliance breakages, and periodontal scores were used as measures of patient compliance. RESULTS: Sixty participants completed the study. At T2 there was no change in anxiety scores for either group (P = .412); however, increased motivation was detected in the group that had been given both written and verbal information (P = .049). At T3 both groups demonstrated similar reductions in anxiety (P = .311) and apprehension (P = .790) and similar levels of motivation (P = .756). A reduction in periodontal scores (P = .065), better appointment attendance (P = .732), and fewer breakages (P = .525) were reported in the group that was given additional information, although these changes were not statistically significant. CONCLUSIONS: Supplementation of verbal information with written information resulted in improved motivation for orthodontic treatment but had no statistically significant effect on anxiety, apprehension, or patient compliance.

The relationship between craniofacial anatomy and obstructive sleep apnoea: a case-controlled study.

The aim of the study was to identify craniofacial and pharyngeal anatomical factors directly related to obstructive sleep apnoea (OSA). The design and setting was a hospital-based, case-controlled study. Ninety-nine subjects (78 males and 21 females) with a confirmed diagnosis of OSA, who were referred to the Dental Hospital for construction of a mandibular advancement splint were recruited. A similar number of control subjects, matched for age and sex, were recruited after completing snoring and Epworth Sleepiness Scale questionnaires to exclude habitual snoring and daytime sleepiness. An upright cephalogram was obtained and skeletal and soft tissue landmarks were traced and digitized. In OSA subjects the anteroposterior skeletal measurements, including maxillary and mandibular length were reduced (P < 0.001). The intermaxillary space was found to be 3.1 mm shorter in OSA subjects (P = 0.001). The nasopharyngeal airway in OSA subjects was narrower (P < 0.001) but pharyngeal length showed no difference. The tongue size was increased (P = 0.021), soft plate length, thickness and area were all greater (P < 0.001) and the hyoid bone was more inferiorly positioned in OSA subjects (P < 0.001). This study identifies a significant number of craniofacial and pharyngeal anatomical factors directly related to OSA.

A thermoplastic mandibular advancement device for the management of non-apnoeic snoring: a randomized controlled trial.

This randomized, controlled, crossover trial assessed the effectiveness of an adjustable, thermoplastic, mandibular advancement device (MAD), the TheraSnore, in the management of non-apnoeic snoring. Twenty-three adults who had been referred for a MAD wore the appliance in both a non-advanced and advanced position for 4-6 weeks: the starting position of the MAD was randomized. The outcomes were assessed at baseline and after each phase of MAD wear using questionnaires [(Epworth Sleepiness Scale, snoring history, sleep disturbance, side-effects of the appliance) and a visual analogue scale (daytime sleepiness)]. Eleven subjects had overnight sleep studies at baseline and with the appliance in each position to assess snoring frequency (snores/hour), oxygen saturation, and apnoea hypopnoea index. Supine radiographs were used to examine the oropharyngeal airway at baseline and in response to both appliance positions. In comparison with the non-advanced appliance, the advanced MAD reduced the snores per hour from a median of 398 to 17 (P = 0.002). Sleeping partners reported a marked improvement in their own daytime tiredness (P = 0.002) and sleep disturbance (P = 0.001) when the subject wore the active appliance. The most common side-effect was a dry mouth and 64 per cent of subjects considered the appliance bulky. Radiographic analysis revealed significant vertical opening associated with the appliance and small but significant post-lingual changes with protrusion. The results suggest that the advanced TheraSnore MAD is effective in the treatment of snoring in two out of three non-apnoeic snorers, their sleeping partners derive benefits from this form of treatment, and that complaints of bulkiness and dry mouth may to be related to the inherent vertical opening of the TheraSnore.

Sleep nasendoscopy: a diagnostic tool for predicting treatment success with mandibular advancement splints in obstructive sleep apnoea.

This prospective, cohort study evaluated the role of sleep nasendoscopy (SNE) with simultaneous mandibular protrusion in predicting successful mandibular advancement splint (MAS) therapy in subjects with obstructive sleep apnoea (OSA). Nineteen OSA subjects diagnosed by overnight polysomnography were referred for MAS therapy, following SNE investigation. A Herbst MAS was fabricated for each subject. Once this had been adjusted for maximal, subjective, therapeutic effect, follow-up sleep studies were undertaken with the appliance in situ. The SNE was repeated with the appliance in place to allow the effects of the original mandibular protrusion and the actual effect of the MAS to be compared. The MAS was removed and the original and current site(s) of obstruction evaluated. Pre-treatment SNE showed airway obstruction at the following levels: intermittent multi-level (16 subjects), sustained multi-level (two subjects) and tongue base (one subject). In all individuals, gentle advancement of the mandible during SNE improved airway patency and reduced snoring. When the SNE was repeated with the MAS in situ, all subjects showed improvements in snoring and airway patency. Follow-up sleep studies confirmed the efficacy of the MAS, with all patients showing a reduction in the apnoea/hypopnoea index (AHI). Median reductions in AHI (from 28.1 to 6.1, P < 0.001) and Epworth Sleepiness Scale (ESS) scores (from 9 to 6, P < 0.001) were highly statistically significant. The results suggest that SNE with concomitant mandibular advancement to mimic MAS wear, could be a valuable prognostic indicator of successful MAS treatment.

Postural variation in oropharyngeal dimensions in subjects with sleep disordered breathing: a cephalometric study.

This radiographic study analysed the changes that occurred in the airway and surrounding structures when subjects with sleep disordered breathing moved from the upright to the supine position. Radiographs of 100 dentate, Caucasian males were examined. Fifty individuals were non-apnoeic snorers and in 50 a diagnosis of obstructive sleep apnoea (OSA) had been confirmed by polysomnography. Radiographs were traced and digitized and comparisons were made of the behaviour of the oropharynx, soft palate, tongue, and hyoid between the two groups. When moving from the upright to the supine position, both OSA and snoring subjects showed a similar pattern of change. The antero-posterior dimensions of the oropharyngeal airway decreased highly significantly (P < 0.001) at all levels, with a concomitant reduction in cross-sectional area (P < 0.001). The narrowing was most severe behind the soft palate, where the minimum airway reduced by approximately 40 per cent. Behind the tongue, a 20 per cent decrease was seen. The soft palate showed small but significant increases in area, whilst the tongue altered in shape but not in its overall cross-sectional area. In non-apnoeic snorers only, tongue proportion increased (P < 0.05). At the same time, the hyoid dropped and moved anteriorly, maintaining a constant relationship with the lower border of the mandible. There were no differences between the non-apnoeic snorers and the OSA subjects in any of the postural changes recorded.