Physical findings and the risk for obstructive sleep apnea. The importance of oropharyngeal structures

In this study, we hypothesized that anatomic abnormalities of the oropharynx, particularly narrowing of the airway by the lateral pharyngeal walls, tonsils, and tongue, would be associated with an increased likelihood for obstructive apnea among patients presenting to a sleep disorders center. To test this hypothesis, we used data from a cohort of 420 patients presenting to the Penn Center for Sleep Disorders. Associations between individual variables in the clinical evaluation model and sleep apnea as defined by a respiratory disturbance index greater than or equal to 15 events per hour were characterized by odds ratios (ORs) with 95% confidence intervals (CIs). Multivariable logistic regression was used to simultaneously estimate ORs for multiple variables and to control for other relevant patient characteristics. Results showed that narrowing of the airway by the lateral pharyngeal walls (OR = 2.5; 95% CI, 1.6-3.9) had the highest association with obstructive sleep apnea (OSA) followed by tonsillar enlargement (OR = 2.0; 95% CI, 1.0-3.8), enlargement of the uvula (OR = 1.9; 95% CI, 1.2-2.9), and tongue enlargement (OR = 1.8; 95% CI, 1.0-3.1). Low-lying palate, retrognathia, and overjet were not found to be significantly associated with OSA. Controlling for BMI and neck circumference, only lateral narrowing and enlargement of the tonsils maintained their significant (OR = 2.0 and 2.6, respectively). A subgroup analysis examining differences between male and female subjects showed that no oropharyngeal risk factor achieved significance in women while lateral narrowing was the sole independent risk factor in men. These findings suggest that enlargement of the oropharyngeal soft tissue structures, particularly the lateral pharyngeal walls, is associated with an increased likelihood of OSA among patients presenting to sleep disorders centers.

Occlusal plane alteration in orthognathic surgery

This article discusses correction of functional and esthetic deformities by surgically increasing or decreasing the occlusal plane angulation. Clockwise rotation, or increase of the occlusal plane angulation, is a well-accepted technique in orthognathic surgery. However, counterclockwise rotation (decrease of the occlusal plane angulation), has not been a well-accepted treatment approach. The functional and esthetic characteristics of the low occlusal plane and the high occlusal plane facial types are presented, specific surgical approaches to alteration of the occlusal plane are described, and the long-term stability of results with both clockwise and counterclockwise rotations of the occlusal plane are discussed. Cases illustrating the application of these surgical approaches are presented.

A sella turcica bridge in subjects with severe craniofacial deviations

In earlier studies, a sella turcica bridge was stated to occur in 1.75 to 6 per cent of the population. The occurrence of a sella turcica bridge has not previously been studied in a group of patients with craniofacial deviations treated by surgery. Profile radiographs from 177 individuals who had undergone combined orthodontic and surgical treatment at the Copenhagen School of Dentistry were studied. A sella turcica bridge was registered in those subjects where the radiograph revealed a continuous band of bony tissue from the anterior cranial fossa to the posterior cranial fossa across the sella turcica. Two types of sella turcica bridge were identified. A sella turcica bridge occurred in 18.6 per cent of the subjects.

Neonatal Distraction Surgery for Micrognathia Reduces Obstructive Apnea and the Need for Tracheotomy

The objective of the study was to assess the effectiveness of neonatal mandibular distraction in treatment of obstructive sleep apnea in the perinatal period in preventing a tracheotomy. This was a prospective study of 17 infants at two centers with severe micrognathia who demonstrated obstructive sleep apnea refractory to conservative therapy. Age at surgery varied from 5 to 120 days. Distraction was performed at a rate of 2 mm/d. After distraction, callus consolidation was allowed for 4 to 6 weeks, and the device was then removed. Each child underwent a three-dimensional computed tomography scan before surgery and approximately 3 months after surgery. Of the 17 patients, 14 successfully underwent extubation and demonstrated significant improvement in the obstructive sleep apnea. Postoperative horizontal ramus length increased from 23.3 to 34.8 mm after surgery. Mean maxillary mandibular discrepancy was 8.28 mm before surgery and 2.2 mm after surgery. Ten infants who underwent pre- and postoperative polygraphic studies showed improvement in obstructive apnea. Three patients had postoperative polysomnographic studies only; the results were also within the normal range. The mean follow-up interval was 16.5 months (range: 8-48 months). Neonatal distraction is an effective method for treatment of micrognathia with obstructive sleep apnea in the perinatal period in preventing a tracheotomy.

Treatment of hemimandibular hyperplasia: The biological basis of condylectomy

Treatments to correct skeletal deformities in patients with hemimandibular hyperplasia differ, particularly about the age at which the operation is done and the operation itself. To some extent, the differences can be attributed to the unknown biological basis of disease. The aim of the present study was to evaluate clinically the outcome of a rationale for the operation based on condylectomy on the affected side. Histological, radiological, and nuclear methods were used to get a more detailed insight into the reason for the operation. Six patients with hemimandibular hyperplasia were treated by a combined orthodontic-maxillofacial protocol. All patients had the affected joint removed. The histological morphology of each condylar specimen was compared with the bone scintigraphy to try and find a correlation between the methods. The clinical evaluation showed morphological and functional rehabilitation of all six patients. During the 2-year follow-up, all patients had stable symmetrical mandibles with no disturbance of temporomandibular function. Remodelling of the joint and the destruction of the cartilaginous layer was accompanied by much bone scintigraphic activity. We conclude that condylectomy can correct hemimandibular hyperplasia, even in patients with active condylar growth, by removing the underlying disease.

Stability of Le Fort I osteotomy with maxillary advancement: a comparison of combined wire fixation and rigid fixation

PURPOSE

This study compares two types of fixation: intraosseous wires, skeletal suspension wiring, and maxillomandibular fixation (combined wire fixation; CWF) with rigid internal fixation (RIF) in patients who underwent Le Fort I osteotomy to correct maxillary hypoplasia.

MATERIALS AND METHODS

All patients were operated on by the same surgeon using a standard technique, which included bone grafting. The 12 patients in group A were treated with CWF for 4 weeks. Group B was made up of 13 patients who had RIF and training elastics for 4 weeks. Cephalometric analysis using a commercial software package was performed on radiographs that were taken immediately preoperatively (T1), 1 day postoperatively (T2), and at least 1 year postoperatively (T4). The position of the maxilla in relation to the cranial base and Frankfort plane at each time interval was compared.

RESULTS

Postsurgical horizontal change (maxillary position change from T2 to T4) for both groups was in the posterior direction. In group A, six patients had less than 1 mm change, three had 1 to 2 mm change, and three had > 2 mm change. In group B, 10 patients had less than 1 mm change, three had 1 to 2 mm change and 0 had > 2 mm change. Comparison of mean values of groups A and B suggested improved stability with rigid versus wire fixation in the horizontal plane; however, statistical analysis of adjusted mean values showed no significant difference. Vertical changes in maxillary position were also measured from postoperatively to 1 year (T2 to T4). The vertical changes were minimal in those cases of maxillary advancement where no vertical changes were planned; however, there was a statistically significant (P = .0024) improved stability with RIF versus combined wire fixation cases. Comparison of adjusted means showed double the amount of vertical setting 1 year postoperatively in the CWF group.

CONCLUSION

Overall, 22 of 25 patients with horizontal maxillary advancement had excellent stability at 1 year. Observed trends suggest that RIF may have improved stability over CWF.

Adequacy of maxillary dental arch width in patients with palatally displaced canines

This study investigates maxillary dental arch width in subjects with palatally displaced canines. Pretreatment dental casts of orthodontic patients with one or both maxillary canines palatally displaced (n = 31; male, 10; female, 21) were collected. This sample was matched according to sex and age with pretreatment dental casts from unaffected orthodontic patients. Arch widths were recorded between the maxillary first premolars and between the maxillary first molars. Interpremolar arch width and intermolar arch width comparisons between the sample with palatally displaced canines and the reference sample showed no statistically significant differences in their means, thus indicating that there was no statistically significant difference in the anterior and posterior arch width between the affected subjects and the control subjects. Thus, affected patients exhibit adequacy of maxillary dental arch width. This evidence refutes earlier conclusions that deficiency in maxillary transverse arch width is an associated contributing factor in the genesis of the anomaly of palatally displaced canines. Clinically, adequacy of dental arch width helps explain the "nonextraction" diagnostic appearance of most of these patients when they present for treatment.

Cervical column morphology related to head posture, cranial base angle, and condylar malformation

The present study describes the cervical column as related to head posture, cranial base, and mandibular condylar hypoplasia. Two groups were included in the study. The 'normal' sample comprised 21 subjects, 15 females aged 23-40 years (mean 29.2 years), and six males aged 25-44 years (mean 32.8 years) with neutral occlusion and normal craniofacial morphology. The condylar hypoplasia group comprised the lateral profile radiographs of 11 patients, eight females, and three males, aged 12-38 years (mean 21.6 years). For each individual, a profile radiograph was taken to perform a visual assessment of the morphology of the cervical column. For the normal group only, the profile radiographs were taken in the standardized head posture to measure the head posture and the cranial base angle. Cervical column: Morphological deviations of the cervical column occurred significantly more often in the subjects with condylar hypoplasia compared with the normal group (P < 0.05 and P < 0.01, respectively). The pattern of morphological deviations was significantly more severe in the subjects with condylar hypoplasia compared with the normal group (P < 0.01). Cervical column related to head posture and cranial base: The cervicohorizontal and cranial base angles were statistically larger in females than in males (P < 0.05 and P < 0.01, respectively). No statistically significant age differences were found. Only in females was the cervical lordosis angle (OPT/CVT, P < 0.01), the inclination of the upper cervical spine (OPT/HOR, P < 0.05), and the cranial base angle (n-s-ba, P < 0.05) significantly positively correlated with fusion of the cervical column. These associations were not due to the effect of age.

Aetiological aspects of mandibular tooth agenesis--focusing on the role of nerve, oral mucosa, and supporting tissues

The purpose of the present investigation was to consider possible aetiological aspects of mandibular tooth agenesis by comparing the pattern of mandibular molar and premolar agenesis with radiological evidence of the mandibular canal. Orthopantomograms from 33 children affected by agenesis of at least four premolar and/or molar teeth in the mandible were investigated. Three children were affected by ectodermal dysplasia. Two anthropological mandibles with absence of mandibular canals were included in the study for comparison. According to the investigation, agenesis should be divided into three groups, based on an analysis of agenesis location, the presence of nerve canals in the jaws, and finally, data on possible bone, skin and oral mucosa abnormalities. The three aetiological groups suggested are: agenesis related to nerve tissue, agenesis related to the oral epithelium, and agenesis related to the supporting tissue.

Disk displacement and temporomandibular joint symptoms in orthognathic surgery patients

The purpose of this study was to document the prevalence of disk displacement and temporomandibular joint symptoms in orthognathic surgery patients. Fifty-three consecutive patients with different types of dentofacial anomalies were examined clinically and with bilateral arthrography. Disk displacement unilaterally or bilaterally was found in 57% of the patients or 46% of the joints. Displacement with reduction was seen in 38 joints, and displacement without reduction was seen in 11 joints. Fifty-three percent of the patients had pain in the temporomandibular joint or masticatory muscles, 30% of the joints demonstrated clicking, and 4% had crepitation. No association was found between disk displacement and clinical symptoms except for an association between clicking and anterior disk displacement with reduction. Neither could an association between disk displacement and the type of dentofacial anomaly be appreciated. It was concluded that disk displacement was frequent in patients with dentofacial anomalies, but no relationship to temporomandibular joint symptoms and the type of dentofacial anomaly could be clearly demonstrated.

Congenital zygomatico-maxillo-mandibular fusion: a brief case report and review of literature

Congenital maxillomandibular fusion (syngnathia) is rare. The first case was reported in 1936. By 2004, only 25 cases of syngnathia had been reported including 6 cases with fusion of the ascending rami of the mandible with the maxilla and zygomatic complex. This report concerns a 6-month-old girl with a type of congenital fusion of the ascending rami of the mandible with the upper alveolar arch and zygomatic complex that leads to restriction of mouth opening. The clinical features of this anomaly and a brief review of literature are presented.

Cleft palate and congenital lateral alveolar synechia syndrome: case presentation and literature review

Cleft palate and congenital lateral alveolar synechia syndrome remains a rare occurrence. Our patient represents only the fourth case of bilateral alveolar synechia with isolated cleft palate in the world literature and, as such, is only the second patient from the United States. More commonly, additional anomalies are associated. Just more than 50 cases involving intraoral synechiae have been reported. This group of cases has implications on fetal facial growth and cleft palate development because there are no documented cases of lateral interalveolar synechiae without cleft palate. Earlier reports can be grouped as variants along the spectrum. Theories of etiology are discussed.

Hereditary orthodontic anomalies and idiopathic scoliosis

Our study of 202 patients aged from 7 to 17 years treated for idiopathic scoliosis, and with a Cobb angle from 20 degrees to 50 degrees, showed a higher frequency of hereditary orthodontic anomalies than those in the control group. There was unmistakable evidence that acquired orthodontic anomalies occurred in both groups at the same rate of frequency. Our study demonstrated unequivocally that the detection of hereditary orthodontic anomalies in young children allows the identification of a group of children who have a high risk of developing scoliosis in later years.

Head and neck manifestations of tumoral calcinosis

Intraoral facial and laryngeal features of tumoral calcinosis are reviewed in six patients of Jewish-Yemenite descent. Extraoral features included calcified masses, erythematous patches, and angular cheilitis. Oral soft tissue findings included papillary hyperplasia of the lip vermilion and velvety-red macules on the tongue, palate, and buccal mucosa. Gingival findings included advanced periodontitis and an erythematous marginal gingivitis. In all patients, orthognathic evaluation revealed a concave profile, retruded maxilla, and relative mandibular prognathism. Although previously reported clinical dental abnormalities were not present, extracted teeth demonstrated abnormal dentin. Hoarseness was present in all patients and was the earliest appearing feature in two patients. The appearance of these head and neck findings preceded the classical manifestations of tumoral calcinosis and may be helpful in the early diagnosis of this entity. The varied reported features of tumoral calcinosis support the notion that this disease may present multiple formes frustes with variable clinical expressivity.

Congenital fusion of the maxilla and mandible: brief case report

Congenital fusion of the mandible and maxilla is a rare anomaly usually seen in association with various syndromes. Reports of isolated cases of bony fusion of the jaws are sparse. Only 10 reported cases were found in the literature search. Maxillomandibular fusion restricts mouth opening, causing feeding problems and difficulties in swallowing, respiration, growth, and development, and thus must be treated early. We report a case of congenital fusion of the mandible and maxilla in a 1-year-old boy and describe the clinical features of this anomaly to add to the existing literature on the subject. This is our second encounter of such a case.

Speech production before and after orthognathic surgery: a review

A review of investigations in which speech production has been studied before and after orthognathic surgery indicates that many subjects demonstrate preoperative articulation errors. The error type most frequently identified was of the distortion variety, which suggests that misarticulating speakers were attempting to produce the sounds but that in most cases the sounds were phonetically incorrect. The /s/ speech sound and the sibilant class in general, of which /s/ is a member, were often found defective in the subjects' speech. Not all speakers had preoperative articulation errors, which suggests the possibility of compensatory articulation patterns. The literature indicates that some persons with certain occlusal and dental conditions do compensate for structural aberrations. Finally, the vast majority of subjects with preoperative misarticulations eliminated or reduced their errors following orthognathic surgery. In the case of speech behavior, it can be stated that surgical alterations in form brought about positive changes in function.

Bilateral hyperplasia of the mandibular coronoid processes associated with the nevoid basal cell carcinoma syndrome in an Italian boy

In this report we present a subject affected by nevoid basal cell carcinoma syndrome (NBCCS), showing also bilateral mandibular coronoid processes hyperplasia, a hitherto unreported association. Our observation of bilateral hyperplasia of the mandibular coronoid processes in a boy with NBCCS may prompt a retrospective and prospective review of other patients affected by this syndrome in order to establish if this anomaly is part of it.

Oropharyngeal hairy polyp with meningothelial elements

The so-called hairy or teratoid polyp is a rare lesion of bigerminal origin that comprises elements derived from both ectodermal and mesodermal cell lines. In this article we report the presence of meningothelial elements in a hairy polyp, a previously undescribed component of this entity. The lesion was characterized by a pedunculated outgrowth from the hard palate. The surface of the outgrowth was covered by squamous epithelium and a central core of fibroadipose tissue, pilosebaceous glands, cleftlike pseudovascular spaces, and groups of epithelioid cells. These reticulated and cellular foci had the immunohistochemical and ultrastructural features of meningothelial tissue.

Reduction cheiloplasty: its role in the correction of dentofacial deformities

The presence of prominent lips is common in individuals with various dentofacial and craniofacial deformities. The aetiology must be diagnosed to differentiate between pseudo-macrochelia and true macrocheilia. When considering surgical correction of the prominent lip, a precise description of the location and the magnitude of the deformity is required. With careful treatment planning, proper sequencing of the treatment, and a good understanding of the various surgical techniques, optimum results can be achieved. These aspects will be discussed in detail illustrated with appropriate cases.