The impact of pharyngeal fat tissue on the pathogenesis of obstructive sleep apnea.

PURPOSE: Obesity is the most important risk factor for obstructive sleep apnea (OSA); however, the exact underlying mechanisms are still not fully understood. The aim of this study was to examine the morphology of upper airways in overweight habitual snorers and in mild OSA patients. Furthermore, the associations between weight loss, parapharyngeal fat pad area and OSA were assessed in a 1-year randomised, controlled follow-up study originally conducted to determine the effects of lifestyle changes with weight reduction as a treatment of OSA. METHODS: Thirty-six overweight adult patients with mild OSA [apnea-hypopnea index (AHI) 5-15 events/h] and 24 weight-matched habitual snorers (AHI < 5 events/h) were included in the study. All patients underwent nocturnal cardiorespiratory recordings and multislice computed tomography (CT) of parapharyngeal fat pad area, the smallest diameter and area in naso-, oro- and hypopharynx, the smallest diameter and area of the whole pharyngeal airway, the distance from the hyoid bone to the mandibular plane and to cervical tangent as well as the distance between mandibular symphysis and cervical spine. In addition, OSA patients were further randomised to receive either an active 1-year lifestyle intervention with an early weight loss programme or routine lifestyle counselling. After 1 year, the cardiorespiratory recordings and CT scans were repeated. RESULTS: The pharyngeal fat pad area was significantly larger, and the distance from the hyoid bone to cervical spine was longer in patients with OSA than in habitual snorers (p = 0.002 and p = 0.018, respectively). The multiple regression analysis showed that besides a large pharyngeal fat pad area and a long distance from the cervical spine to hyoid bone, also a short distance from the mandibular symphysis to cervical tangent increased a risk to OSA. During the 1-year follow-up in OSA patients, the pharyngeal fat pad area and AHI decreased significantly in the intervention group (p = 0.003 and p < 0.001, respectively). CONCLUSIONS: In the early stages of OSA, the pharyngeal fat pad seems to play an important role in the development of disease in overweight patients. Furthermore, weight reduction by lifestyle intervention-based programme reduces both central obesity and pharyngeal fat pads, resulting in an improvement of OSA.

Palatal training appliances in children with mild to moderate oral dysfunctions.

OBJECTIVE: The objective of the study was to evaluate the efficacy of palatal training appliances on speech articulation and orofacial functions in children undergoing speech therapy. STUDY DESIGN: The material consisted of 134 boys and 34 girls who were referred by speech and language therapists to the Public Dental Health Service in Vantaa due to mild to moderate problems with speech articulation or in oral motor skills. The mean age of the children at the start of the palatal plate therapy was 6.4 years (SD 1.9). The articulation assessment was performed by five speech and language therapist while the palatal plate therapy was carried out by an experienced dentist. The mean treatment time with the oral plates was 4.4 months (SD 2.3). RESULTS: An improvement in speech articulation was observed by the speech and language therapists in 51% of the children. Tongue movements improved in 47%, and lip closure in 38% of the participants. Drooling decreased in 54% of the cases. A multiple logistic regression model revealed that with respect to speech articulation the best improvement was found in children with /r/-disorder and in those with a crossbite. CONCLUSIONS: Palatal training appliances during speech therapy seemed to be an efficient way to improve speech articulation and tongue movements in children with mild to moderate problems in orofacial functions.

Do early signs of orofacial dysfunctions and occlusal variables predict development of TMD in adolescence?

The aim of the present report was to focus on if early signs of different orofacial dysfunctions, e.g. misarticulations of speech, problems in oral motor skills and TMD, malocclusions or occlusal interferences could predict the development of temporomandibular disorders (TMD) in adolescence. Altogether there were 94 children referred for speech therapy and 93 controls who participated in all three stages of this longitudinal study. In the whole sample the mean age during the first examination was 7.6 years, during the second examination 10.6 years, and during the third one 15.4 years. Multiple logistic regression models showed that subjects with a tendency to open bite tended to have palpatory tenderness of the muscles. Overjet was positively related to hypermobile but negatively to hypomobile jaw movements. Deviation on opening was associated with problems in oral motor skills, and some signs of TMD seemed to be related to each other. In addition, girls had a higher risk of having several signs of TMD than boys did. In conclusion, tendency to open bite, both mesial and distal molar occlusion and increased and decreased overjet were occlusal anomalies associated with TMD. Altogether, among 15-year-olds there seems to be both local and central factors in the aetiology of TMD.

Changes in TMD signs and in mandibular movements from 10 to 15 years of age in relation to articulatory speech disorders.

This study is part of a longitudinal study on the associations between different orofacial dysfunctions. The aim was to determine changes in signs of temporomandibular disorders (TMD) and in mandibular movement capacity in subjects with articulatory speech disorders and in controls by re-examining a sample of 187 previously studied children from 10 to 15 years of age. Articulatory speech disorders were diagnosed by a phoniatrician. Mandibular movement capacity, signs of TMD, occlusal contacts/ interference and slide between retruded and intercuspal positions were recorded by a dentist. The follow-up results showed that mandibular mobility mainly increased up to the age of 15, but there was a decrease in protrusion capacity in almost half of the cases. This fluctuation probably reflects the normal changes in growth pattern. Signs of TMDs proved to be inconsistent in nature, especially among the controls. With age, girls in the control group, more so than boys, were prone to new signs of TMD, but no gender difference was found in the group of subjects with misarticulations of speech. The findings indicate that in adolescence different orofacial dysfunctions are related.

Standards for permanent tooth emergence in Finnish children.

Two groups of Finnish children, 1008 from the eastern part of the country and 569 from the western part, aged 5 to 16 years, were examined to determine the timing of permanent tooth emergence and any regional variation therein. The probit analysis was used to calculate the median ages of eruption. Permanent teeth in the first phase of the mixed dentition erupted earlier and premolars erupted later than previously reported for Scandinavian populations. The former finding could reflect the secular trend; the latter is probably related to the dramatically improved dental health in Finnish children. No regional variation in eruption was found. The median ages of eruption of permanent teeth determined in the present study are suggested for use as national standards for permanent tooth emergence in Finland, separately for girls and boys.

Associations among different orofacial dysfunctions in 9-11-year-olds.

This study is the second part of a longitudinal investigation on different orofacial dysfunctions in growing individuals. The aim of the present report was to determine, in 219 children with and without articulatory speech disorders, whether certain associations among misarticulations of speech, craniomandibular disorders (CMD), and problems in oral motor skills still were found at the age of 9-11 years, as they had been in these children at the age of 6-8 years. Multiple logistic regression models showed that certain aspects of dental malocclusion such as large overjet, anterior open bite and lateral cross-bite, and certain signs of CMD such as palpatory tenderness of the TMJ, jaw deviation on opening and bruxism were related to misarticulations of speech. Children with sounds produced too far posteriorly seemed to have a smaller maximal opening but larger laterotrusive and protrusive movement capacities of the mandible than children with correct speech articulation. Despite maturation of the oral motor skills with age, among 9-11-year-olds various orofacial dysfunctions still seemed to be associated with each other. This probably indicates fixation of certain speech misarticulations rather than immaturity of the fine motor control.

Changes in function of the masticatory system from 7 to 10 years of age in relation to articulatory speech disorders.

The aim of the present study was to determine changes in function of the masticatory system in children with articulatory speech disorders and in the controls by re-examining a sample of 287 previously studied children from 7 to 10 years of age. Articulatory speech disorders were diagnosed by the same speech therapist during spontaneous speech and test words using the Remes Articulation Test. Mandibular movement capacity, occlusal interferences, slide between retruded and intercuspal positions, and signs and symptoms of the craniomandibular disorders (CMD) were recorded by a dentist. The follow-up results showed that mandibular movement capacity increased in almost all individuals, decreasing only in about 10% of cases. However, among children with speech disorders lateral jaw movements decreased in about 30% of subjects. During growth the prevalence of CMD increased while single signs and symptoms fluctuated. Differences between the groups for expression of CMD, mandibular movement capacity and occlusal recordings mainly levelled off. Higher constancy of subjective symptoms and retrusive interferences in children with speech disorders than in the controls supports our previous findings that, in growing individuals, different orofacial dysfunctions seem to be associated with each other.

Associations among different orofacial dysfunctions in 6-8 year olds.

Associations among several orofacial dysfunctions such as articulatory speech disorders, craniomandibular disorders (CMD) and problems in coordinating the orofacial muscles were examined in two groups of Finnish first-graders, i.e. children with and without speech disorders. In the whole sample of 287 subjects the mean age was 7.5 yr. A speech therapist diagnosed articulatory speech disorders and a phoniatrician examined the morphology and function of the articulators. Signs and symptoms of CMD, capacity for mandibular movement, and prevalence of occlusal interferences were examined by a dentist. Deviations in motor skills, but not in morphology of the articulators, were associated with speech disorders. The findings also suggested that capacity for mandibular movement, deviation of the jaw during maximal mouth opening and occlusal interferences were related to certain speech disorders among these 6-8 yr olds. Different orofacial dysfunctions appear to be associated with each other during growth.

Eruption pattern of permanent teeth in a rural community in northeastern Finland.

Cross-sectional data on permanent tooth eruption were collected by examining the children and adolescents 5-15 years old in a northeastern municipality of Finland. There were 1008 subjects in the whole sample, 483 girls and 525 boys. The results showed statistically significant differences between the girls and boys in timing of eruption of some permanent teeth, indicating earlier eruption in girls than in boys. This difference was most clearly seen in the second phase of the mixed dentition. Interindividual variation in the emergence age was also wider in the second phase of the mixed dentition. The present results seem to indicate earlier eruption of the permanent teeth in rural children in northeastern Finland than in other parts of the country.

Relationship between craniomandibular dysfunction and pattern of speech sound production in a series of first-graders.

This report investigates associations between prevalence of functional disturbances of the masticatory system and speech disorders. The subjects were 157 children referred for speech therapy to the hospital and a control group all 130 first-graders at two elementary schools, mean age 7 years 6 months. During clinical examinations, signs and symptoms of TMJ dysfunction were recorded by the same dentist. Articulatory speech disorders were diagnosed by the same phoniatrician using the Remes Articulatory Test (Remes, 1975) for the Finnish language. The results showed that in the hospital referral group the mean value for maximal opening was smaller while laterotrusion movements and maximal protrusion of the mandible were larger than in the control group. The study group also more often had CM disorders and occlusal interferences than children of the first grade sample. In the present data, a higher frequency of subjective symptoms and several clinical signs of CMD were related to certain articulatory speech disorders. Risk of having too anteriorly-produced sounds, mainly 's'-sounds, decreased with advancing age in 6-8-year-old children. In conclusion, expression of both craniomandibular disorder and disorders in speech sound production seem to a considerable extent to reflect immaturity of fine motor control of the orofacial muscles in 6-8-year-old children.

Developmental stage of the dentition and speech sound production in a series of first-grade schoolchildren.

This study was undertaken to investigate the effect of developmental stage of the dentition on speech sound production in children with and without articulatory speech disorders. In the whole sample, there were 281 subjects, mean age 7.5 years (SD 0.4). The stage of the eruption of the permanent incisors was calculated as the percentage height of each tooth of the mean crown height of the corresponding tooth in a group of 252 young adults. Eruptional stage of the first permanent molars was classified into three categories. Articulatory disorders were diagnosed by one experienced speech therapist and phoniatrician using the Remes Articulation Test [Remes, 1975] for the Finnish language. The results showed a wide interindividual variation in developmental stage of the dentition in a group of 7-year-old children with a tendency of the first permanent molars but not the incisors to erupt earlier in girls than in boys. Boys had a higher frequency of misarticulations estimated to need treatment than did girls. The present results indicate that during eruption of permanent teeth it is more important to draw attention to symmetrical eruption and to individual timing pattern rather than to the mean values of tooth eruption in subjects of the same age. The findings also suggest a decreasing risk of faulty speech sound production with advancing eruption of some permanent teeth still present in 7-year-old children.

Variation in function of the masticatory system in 1008 rural children.

The aim on the present study was to investigate the variation in function of the masticatory system in 1008 subjects 5 to 15-years-old in a rural community. This study considered the effects of age, gender, developmental stage of the dentition and interexaminer variability. In addition, maximal opening capacity of the mandible was assessed in relation to age, gender and body size. Four dentists performed the examinations combined with routine check-ups, preventive and operative dental treatments. The results showed that the opening capacity in children increases from the age of 6 to the age of 12 with no difference between the sexes. Children of bigger size seem to have larger opening than the smaller ones. Minor differences were found between the sexes, but some variation with age could be seen in signs of craniomandibular disorders (CMD) and in occlusal recordings. Children with RP-IP slide had more often CMD-signs than the ones without this occlusal feature mainly from the instability of occlusion. This is in accordance with the finding of a higher prevalence of muscle tenderness and mediotrusion interferences during the mixed dentition. In general, in children expression of the craniomandibular disorders seems to reflect physiological changes during development of the dentition and occlusion rather than a pathological condition.