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1. Thoracic insufficiency syndrome is the inability of the thorax to support normal respiration or lung growth. 2. The rare condition of fused ribs and congenital scoliosis may result in a three-dimensional thoracic deformity with adverse effects on thoracic growth and function with development of thoracic insufficiency syndrome. 3. The normal thorax is defined by two characteristics: normal, stable volume and the ability to change that volume. Volume depends on the width and depth of the rib cage, and the thoracic spine provides height. The ability to change volume, termed thoracic function, is provided by the diaphragm and the secondary muscles of respiration. 4. On radiographs, the loss of the vertical height of the lung of the concave, restricted hemithorax is defined by the percentage of space available for the lung. 5. Spine rotation causes a windswept thorax, with both restriction of the volume of the convex hemithorax and restriction of the motion of the involved ribs. 6. Constrictive three-dimensional deformity of the thorax may cause extrinsic, restrictive lung disease. 7. Progressive thoracic insufficiency syndrome is diagnosed on the basis of clinical signs of respiratory insufficiency, loss of chest wall mobility as demonstrated by the thumb excursion test, worsening indices of three-dimensional thoracic deformity on radiographs and computed tomography scans, or a relative decline in percent predicted vital capacity due to thoracic "failure to thrive," as demonstrated by pulmonary function tests. 8. Treatment of progressive thoracic insufficiency syndrome should provide an acute increase in the thoracic volume with stabilization of any flail chest-wall defects and maintain these improvements as the patient grows, without the need for spine fusion.

Objective. The goal of this study was to quantify condylar position changes after mandibular advancement surgery with rigid fixation (screws). Radiographic changes in condylar position were determined in all planes (X, Y, and Z). Computed tomography with image reconstruction was used. Study Design. A consecutive population of patients who elected to have rigid fixation for surgical stabilization method were studied (n = 21). Computed tomography data were acquired in the axial plane through use of abutting 1.5-mm–thick slices. Data acquisition occurred 1 week preoperatively and 8 weeks postoperatively. Measurements were made from 2-dimensional reconstructions. Results. The averages were as follows: lateral displacement from midline, 1.2 mm (55% of patients); medial displacement from midline, 1.5 mm (45% of patients; range, 3.2 mm); condyle angle increase from coronal plane, 3.5 degrees (60% of patients); condyle angle decrease from coronal, 4.3 degrees (40% of patients; range, 8.5 degrees); superior rotation of proximal segment, 3.2 degrees (39% of patients); inferior rotation of proximal segment, 8.6 degrees (61% of patients; range, 15.6 degrees); superior displacement, 1.2 mm (60% of patients); inferior displacement, 1.0 mm (40% of patients; range, 2.5 mm); anterior displacement, 1.6 mm (33% of patients); posterior displacement, 1.6 mm (67% of patients; range, 2.8 mm). Conclusions. Changes occurred in all planes, but the most common postoperative condyle position was more lateral; with increased angle, the coronoid process was higher and the condyle was more superior and posterior in the fossa. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;87:159-65)

Purpose: This study compares the usefulness of axial computed tomography (CT) with two-dimensional (2D) reformats and three-dimensionally (3D) rendered CT data in the treatment planning and management of patients. Patients and Methods: Twenty-nine patients who had been studied with CT were grouped into the following four clinical problems: 1) temporomandibular joint assessment (n = 8), 2) growth and development assessment (n = 4), 3) posttrauma and postoperative assessment (n = 13), 4) “other” (n = 4). The clinicians who treated these patients were surveyed for their opinions of the usefulness of CT with and without 2D/3D reformatting. Results: In a majority of the cases within each of the four clinical groups, the clinicians believed that 2D and/or 3D reformatting of the CT data provided additional useful information for patient management. In most of the cases, 3D imaging provided information in addition to that provided by the axial or reformatted 2D images. Conclusion: 2D and 3D CT images can be useful to the clinician in diagnosis and treatment planning. These methods enhance the accuracy of diagnostic decisions and the establishment of appropriate treatment plans.

Background: Thoracic insufficiency syndrome is the inability of the thorax to support normal respiration or lung growth and is seen in patients who have severe congenital scoliosis with fused ribs. Traditional spinal surgery does not directly address this syndrome. Methods: Twenty-seven patients with congenital scoliosis associated with fused ribs of the concave hemithorax had an opening wedge thoracostomy with primary longitudinal lengthening with use of a chest-wall distractor known as a vertical, expandable prosthetic titanium rib. Repeat lengthenings of the prosthesis were performed at intervals of four to six months. Radiographs were analyzed with respect to correction of the spinal deformity, as indicated by a change in the Cobb angle, and lateral deviation of the spine, as indicated by the interpedicular line ratio. Spinal growth was assessed by measuring the change in the length of the spine. Correction of the thoracic deformity and thoracic growth were assessed on the basis of the increase in the height of the concave hemithorax compared with the height of the convex hemithorax (the space available for the lung), the increase in the thoracic spinal height, and the increase in the thoracic depth and width. The thoracic deformity in the transverse plane was measured with computed tomography, and the scans were analyzed for spinal rotation, thoracic rotation, and the posterior hemithoracic symmetry ratio. Clinically, the patients were assessed on the basis of the relative heights of the shoulders and of head and thorax compensation. Pulmonary status was evaluated on the basis of the respiratory rate, capillary blood gas levels, and pulmonary function studies. Results: The mean age at the time of the surgery was 3.2 years (range, 0.6 to 12.5 years), and the mean duration of follow-up was 5.7 years. All patients had progressive congenital scoliosis, with a mean increase of 15°/yr before the operation. The scoliosis decreased from a mean of 74° preoperatively to a mean of 49° at the time of the last follow-up. Both the mean interpedicular line ratio and the space available for the lung ratio improved significantly. The height of the thoracic spine increased by a mean of 0.71 cm/yr. At the time of the last follow-up, the mean percentage of the predicted normal vital capacity was 58% for patients younger than two years of age at the time of the surgery, 44% for those older than two years of age (p < 0.001), and 36% for those older than two years of age who had had prior spine surgery. In a group of patients who had sequential testing, all increases in the volume of vital capacity were significant (p < 0.0001), but the changes in the percentages of the predicted normal vital capacity were not. There was a total of fifty-two complications in twenty-two patients, with the most common being asymptomatic proximal migration of the device through the ribs in seven patients. Conclusions: Opening wedge thoracostomy with use of a chest-wall distractor directly treats segmental hypoplasia of the hemithorax resulting from fused ribs associated with congenital scoliosis. The operation addresses thoracic insufficiency syndrome by lengthening and expanding the constricted hemithorax and allowing growth of the thoracic spine and the rib cage. The procedure corrects most components of chest-wall deformity and indirectly corrects congenital scoliosis, without the need for spine fusion. The technique requires special training and should be performed by a multispecialty team. Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Child abuse is a disturbingly common finding in society today. There have been substantial and significant increases in the incidence of child abuse since the last national incidence study was conducted in 1986. Kassebaum first reported the under-reporting of child abuse by Texas dental professionals in a survey in 1986. The objective of the current study was twofold: (1) assess the level of knowledge and attitudes among dental professionals on the important issue of child abuse; (2) evaluate and compare the results of the current study with a similar survey conducted in 1986.A 24-question survey similar in format and content to the 1986 questionnaire was mailed to 1,046 Texas dentists, randomly selected from a membership roster provided by the Texas Dental Association. Both general dentists and selected specialists were included in the study group. The questionnaire consisted of multiple-choice and dichotomous yes/no questions.There were 383 responses to the questionnaire, yielding a response rate of 38%. The majority (N=289) of the respondents were general dentists. In answering questions about suspected and reported cases of child abuse, nearly 50% of the responding dentists reported they had suspected at least 1 case of child abuse. In the 1986 study, only 36% of the responding dentists reported they had suspected at least 1 case of child abuse. Between 1986 and 2001, the survey has shown that the percentage of dentists who reported at least 1 case to authorities slightly increased from 19% in 1986 to 25% in 2001, but the ratio of suspected to reported cases had not changed since 1986.Although the composite percentage of suspecting and reporting cases of child abuse from this survey is higher than the percentage demonstrated in 1986 study, there was no significant change in the relative ratio of reported cases to suspected cases in both surveys. This indicates that under-reporting of child abuse cases is still a significant problem in the dental profession in Texas.

The purpose of this study was to determine the prevalence, size, location, and morphology of maxillary sinus septa in dentate, partially dentate, and edentulous maxillae.Data from 312 sinuses were analyzed from reformatted computerized tomograms utilizing SIM/Plant software. The sample consisted of 156 patients (106 women and 50 men, with ages ranging between 24 and 86 years and a mean age of 55.4 years) who were being treatment-planned to receive implant-supported restorations.A total of 75 septa were found in 312 maxillary sinuses (24%), which corresponded to 32.7% of the patients (51 of 156). Completely edentulous patients presented with 33.3% of the total septa, while 66.7% of the septa were identified in partially edentulous patients. Analysis of the anatomic location of the septa within the sinus revealed that 18 (24.0%) septa were located in the anterior region, 31 (41.0%) were in the middle, and 26 (35.0%) were in the posterior region. Measurements of height of the septa varied among different areas. The lateral area ranged from 0 to 15.7 mm (with a mean of 3.54 +/- 3.35 mm), the middle area ranged from 0 to 17.3 mm (with a mean of 5.89 +/- 3.14 mm), and the medial area ranged from 0 to 20.6 mm (with a mean of 7.59 +/- 3.76 mm). A total of 20 septa (26.7%) were located in the immediate apical region of teeth. The remaining 55 septa (73.3%) were related to edentulous areas.Septa may arise in any of the 3 regions of the maxillary sinus irrespective of the degree of dentulism or edentulism present.To avoid unnecessary complications during sinus augmentation procedures, adequate and timely identification of the anatomic structures inherent to the maxillary sinus are required.

Purpose: Multiple articles have discussed condylar position after bilateral sagittal split osteotomy (BSSO). However, previous studies have been limited to two-dimensional evaluation of condylar position. The purpose of this study was to evaluate change in condylar position after a BSSO fixed with bicortical screws using three-dimensional computed tomography to assess the factors that may influence the ultimate position of the condyle after surgery. Patients and Methods: Seventeen patients underwent isolated mandibular advancement involving a BSSO with rigid fixation. Reformated axial computed tomography was done 1 week before and 8 weeks after surgery. Movements evaluated included 1) medial-lateral, 2) superior-inferior, 3) anterior-posterior, and 4) condylar angulation. Three separate factors were analyzed to study their effects on the four movements noted: 1) amount of mandibular advancement, 2) amount of proximal segment rotation, and 3) preoperative shape of the mandible. A linear regression analysis was used with statistical significance set at P < .05. Results: Eight weeks after a BSSO and mandibular advancement, most cases showed displacement of the condyle medially, posteriorly, superiorly, and angled medially. The amount of mandibular advancement did not correlate with medial-lateral change of the condyle. The amount of advancement correlated with the condyle angulation and superior-inferior changes in condyle position. There was no correlation between amount of advancement and medial or anterior-posterior change in condyle position. There also was no correlation between any of the condylar movements and the degree of proximal segment rotation or the shape of the mandible. Conclusions: There are obvious changes in condyle position after a BSSO. These changes appear to be influenced mainly by factors other than amount of advancement, degree of proximal segment rotation, and shape of the mandible.

Fifteen patients with complete unilateral cleft lip and palate who had primary alveolar bone grafting were studied with computer-assisted tomography at a mean age of 12 years. Keeping the maxillary alveolar crest parallel to the plane of the scan, 1.5-mm cuts of the maxilla were made from the infraorbital rim to the gingival third of the crowns of the teeth. A single operator reformatted the data into three-dimensional images using the Maxiview 3200 computer workstation. This allowed examination of the position, size, and spatial relationship of the grafted area and quantification of the amount of bone coverage of root surface and bone height of the alveolus in or adjacent to the graft site. Ten patients showed a lateral incisor in the line of the cleft. The average bony coverage of these tooth roots was 76.5 percent. In the five patients in whom there was lateral incisor agenesis, the canine root had average bony coverage of 82.6 percent. The average height of bone at the lateral incisor was 8.7 mm; at the canine, 14.1 mm. In two patients in whom there was only 42 percent tooth root coverage, the teeth were still viable, stable, and without mobility. Computed tomographic (CT) scans of the 15 patients demonstrated good graft survival with adequate volume. The functional and aesthetic status of the dentition in the area of the cleft also was demonstrated.

Objective This investigation was conducted to determine the agreement between three-dimensional (3-D) calculations from CAT scans and two-dimensional (2-D) calculations from standard dental radiographs in evaluating bone support for cleft-adjacent teeth after primary bone grafting. Design This retrospective study utilized CAT scans and dental radiographs taken of the alveolar cleft in patients an average of 11 years after primary bone grafting. Setting The subjects were patients treated by the Cleft Palate Team at Children's Memorial Hospital and Loyola University Medical Center, Chicago, Illinois. Patients Fourteen UCLP patients (9 males, 5 females) agreed to participate In this study by undergoing CAT scan assessment of their alveolar cleft sites. They also had to have periapical or occlusal radiographs of the grafted cleft site taken within 6 months of the CAT scan. Interventions All patients underwent primary lip repair, placement of a passive palatal plate, primary alveolar bone grafting (mean age 6.4 months), and palatoplasty before 1 year of age. Major tooth movement through final orthodontics was completed by the time of the radiographic assessment. Main Outcome Measures CAT scan sections were reformatted and reconstructed to three-dimensionally calculate the percentage of root covered by bone support for the 15 teeth adjacent to the grafted cleft sites. Dental radiographs of the same teeth were also traced and digitized. Percentages of root supported by bone were also established using the dental radiographs by dividing the amount of root covered by bone, by the anatomic root length. Results A paired, two-sample t test revealed no significant differences between the two methods of assessment, while linear regression showed a statistically significant correlation between the CAT scan assessment and the percentages found on the radiographs. Conclusions Routine dental radiographs were able to estimate the total 3-D bone support for the roots of cleft adjacent teeth as determined by CAT scan to a statistically significant degree when groups where compared. The clinical significance for evaluation of individual cases was less impressive with a wide range of variability and a level of agreement that required acceptance of differences up to 25%.

The objective of this article is to familiarize the health care professional with 1990 national data on child abuse and to review some of the trends reported in the literature. The United States was divided into Northeast, Midwest, South, and West. Data were collected, analyzed, and transformed to calculate the incidence and types of abuse reported by region. Variables of interest were income, marital status, perpetrator, age of victim, and drug use by region. To determine significant differences among regions for each type of abuse and related variable, frequency distributions were calculated and chi-squared tests were used. State data summaries were measured for correlation analysis. The West was highest in reported incidence of child abuse (5.9%) and, specifically, physical abuse (36.7%). California reported 55% of the physical abuse in the West. In all regions, neglect and physical maltreatment were reported more than sexual and emotional abuse. The incidence of neglect in the south (52.8%) was greater than in any other region and did not correlate to income in this region. Early detection of child abuse can aid in preventing fatalities. This information should increase awareness of child abuse and result in an increase in reporting if abuse is suspected.

Clinical cases illustrate the diagnostic potential of MRI. Magnetic resonance imaging can be a valuable diagnostic tool. Some fundamental concepts behind MRI are discussed, using clinical cases to illustrate the potential of this imaging system.

Enamel thickness is an important diagnostic characteristic in Hominoidea. However, the sample size is extremely small, relying upon mostly fractured specimens and a few sectioned specimens, providing an estimate of enamel thickness only. What is needed to fully understand the significance of enamel thickness is a non-destructive technique that is able to obtain the thickness, density, and volume of the dental hard tissues of large samples, thereby providing an accurate means of relating thickness, area, volume, and the pattern of distribution of both enamel and dentin. Investigators have attempted to circumvent this problem by developing a variety of indexes. However, we are still left with subjective descriptions, such as 'thin', 'thick', 'intermediate thick', and 'hyperthick'. The purpose of this investigation was therefore to demonstrate the ability of high-resolution X-ray computed microtomography (HRXCT), as a non-destructive method, to produce, accurately and reliably, contiguous slices revealing the thickness and area of enamel, dentin, and pulp chamber. Using imaging software, three-dimensional reconstructions were produced, which provided volume data for enamel and dentin. Three-dimensional reconstruction of HRXCT images provide, for the first time, the capability of accurately quantifying enamel and dentin thickness, distribution and volume, thereby eliminating the necessity of destructive thin-sectional analysis.

The estrogen receptor is a transcription factor which, when bound to estradiol, binds DNA and regulates expression of estrogen-responsive genes. A 160-kilodalton estrogen receptor-associated protein, ERAP160, was identified that exhibits estradiol-dependent binding to the receptor. Mutational analysis of the receptor shows that its ability to activate transcription parallels its ability to bind ERAP160. Antiestrogens are unable to promote ERAP160 binding and can block the estrogen-dependent interaction of the receptor and ERAP160 in a dose-dependent manner. This evidence suggests that ERAP160 may mediate estradiol-dependent transcriptional activation by the estrogen receptor. Furthermore, the ability of antiestrogens to block estrogen receptor-ERAP160 complex formation could account for their therapeutic effects in breast cancer.