Induction of pulmonary tissue maturation in premature infants

Bleeding from the external auditory canal following head trauma is not unusual. It can be caused by a posterior dislocation of the mandibular condyle associated with a fracture of the tympanic bone. Although posterior dislocation is uncommon, it is the second most frequent complication after antero-medial displacement of the condyle. We report four cases of tympanic plate fracture and present CT images demonstrating the range of injuries seen.     

Auditory canal hemorrhage as a symptom of mandibular trauma

Auditory canal hemorrhage is usually a sign of a basal skull fracture. It is commonly unknown that this sign can also be a symptom of combined fracture of the external auditory canal and the mandibular condyle. In our investigations of patients with maxillofacial injuries we found in 15% of 197 fractures of the mandibular condyle within 3 years this combination. In sequence of these results there is a differential diagnostic need for an exact investigation to clear up these various causes in each case as first step toward an accurate therapy. The mechanism of these fractures, their etiology, and therapy are discussed with special reference to possible complications.20     

The assessment of fracture of the mandibular condyle by use of computerized tomography. Incidence of sagittal split fracture

A survey was carried out to clarify the incidence of sagittal splitting fracture of the mandibular condyle using computerized tomography. There were 33 patients, between 11 and 67 years of age, with displaced or dislocated mandibular condylar process fractures (41 cases), seen at our clinic between 1986 and 1992. The incidence of no displacement was 4.9%; deviation and displacement, 34.1%; dislocation, 46.3%; and complete avulsion, 4.9%. A sagittal splitting fracture of condyle occurred with an incidence of 9.8%. Conservative treatment was effective in the treatment of sagittal splitting fracture. Therefore, classification of fracture of mandibular condyle should include the sagittal split fracture, and investigations should include computerized tomography.     

Gadolinium-enhanced MR imaging of temporomandibular disorders: improved lesion detection of the posterior disk attachment on T1-weighted images obtained with fat suppression

OBJECTIVE: The purpose of this study was to assess the potential for improved lesion detection in the posterior disk attachment and its surrounding tissue in temporomandibular disorders when gadolinium-enhanced MR imaging performed with fat suppression is used. MATERIALS AND METHODS: Forty-five patients underwent MR imaging with conventional T1- and T2-weighted, gadolinium-enhanced T1-weighted, and gadolinium-enhanced fat-suppressed spin-echo imaging sequences. Qualitative and quantitative assessments of the contrast enhancement of each type of imaging were also performed. RESULTS: The contrast-enhanced fat-suppressed T1-weighted imaging sequence had several advantages over the other imaging techniques in detecting abnormalities of the posterior disk attachment and in detecting bone marrow lesions in the mandibular condyle. The most significant advantage was better enhancement of lesion conspicuity. The diagnostic accuracy of contrast-enhanced fat-suppressed imaging was 77% versus 70% for conventional contrast-enhanced imaging. The kappa value for interobserver agreement was .95 for contrast-enhanced fat-suppressed imaging and .72 for conventional contrast-enhanced imaging. CONCLUSION: Contrast-enhanced fat-suppressed T1-weighted spin-echo MR imaging is a valuable technique for visualizing the extent and degree of lesions in the posterior disk attachment and bone marrow lesions in the mandibular condyle.     

Fractures of the facial skeleton in Tabuk North West Armed Forces Hospital: a five year review

A five-year review of nine hundred and eighty maxillofacial injuries seen and treated at the Armed Forces Hospital, Tabuk, Saudi Arabia is presented. The dominant age group range was 21-30 years. There were almost twice as many maxillary fractures as mandibular fractures. The most common aetiology was road traffic accidents (RTA), followed by sport traumas. Facial lacerations and contusions followed by neurologic and orthopaedic injuries were the most common concomitant injuries.     

Superolateral dislocation of an intact mandibular condyle into the temporal fossa: a case report

An unusual case of superolateral dislocation of an intact mandibular condyle into the temporal fossa is reported. The different methods of treatment and the difficulties that may arise in the treatment of such cases are discussed briefly, and the literature is reviewed.     

Experimental occlusal interferences. Part IV. Mandibular rotations induced by a pliable interference

In 12 subjects, a pliable, yet unbreakable, intercuspal interference (aluminum shim onlay splint; uniform height of 0.25 mm) was placed between either the right or left maxillary and mandibular second premolars and first molars. During brief and forceful biting (dynamic chewing stroke of about 20 kg force) the interference emulated a semisoft food bolus, and at the end of biting (subsequent static clenching stroke of about 20 kg force) it emulated a rigid metal interference. During dynamic/static biting, rotational electrognathography measured maximum frontal and horizontal plane torque of the right and left mandibular condyles. Eleven subjects (92%) showed frontal plane upward rotation (mean of 1.0 degree) of the condyle contralateral to the interference, and one subject (8%) showed frontal plane upward rotation (0.4 degree) of the condyle ipsilateral to the interference. Two subjects (17%) showed no horizontal plane rotation; seven subjects (58%) showed backward rotation (mean of 0.4 degree) of the condyle contralateral to the interference; and three subjects (25%) showed backward rotation (mean of 0.3 degree) of the condyle ipsilateral to the interference. It is suggested that, in the presence of an occlusal interference, mastication may have both short- and long-term detrimental effects.     

Midfacial growth after costochondral graft construction of the mandibular ramus in hemifacial microsomia

PURPOSE: The purpose of this study was to document vertical midfacial growth after costochondral graft mandibular ramus construction in children with type IIB and type III hemifacial microsomia (HFM). METHODS: This is a retrospective study of 33 children who underwent costochondral graft (CCG) construction for mandibular type IIB (abnormal, small, and medially displaced ramus, n = 19) and mandibular type III (absent ramus and glenoid fossa, n = 14) HFM, between 1980 and 1990. Types I and IIA patients were not included because their milder mandibular deformities were lengthened by osteotomy. Mean age at operation was 6.2 (2 to 10) years, and the mean follow-up period was 5.5 (1 to 13.5) years. Occlusal cant, piriform angle, and intergonial angle were measured on the most current posteroanterior (PA) cephalogram. The ratio of unaffected to affected ramus length was determined on the most current panoramic radiograph. Patient outcomes were classified based on the occlusal cant at the latest follow-up: group 1, successful result with a symmetrical maxilla (occlusal cant of <5 degrees); group 2, acceptable result (occlusal cant > or =5 degrees but <8 degrees), and Group 3, failure (occlusal cant > or = 8 degrees). OMENS scores were calculated for each patient: each of the five major anatomic deformities of HFM (orbital, mandibular, auricular, neural, and soft tissue) were graded 0 to 3 and summed. The mean differences in age at operation and OMENS scores between groups were calculated (ANOVA). RESULTS: At the end of follow-up, patients defined as having a successful result (group 1) had a mean occlusal cant of 2 degrees, a mandibular length ratio of 1.0, and an intergonial angle of 2 degrees. However, the final piriform angle was 7 degrees, indicating less vertical midfacial growth than maxillary alveolar growth. These patients were older at the time of operation (mean age, 6.7 years), and their mean OMENS score (6.3) was significantly lower (P = .004) than in patients in group 2 (mean age at operation, 6.3 years; mean OMENS score, 6.8) and group 3 (mean age at operation, 5.8 years; mean OMENS score, 7.8). In group 2, the occlusal cant, mandibular length ratio, and intergonial and piriform angles did not improve. In group 3, the occlusal cant and piriform angle became worse during the follow-up period. CONCLUSIONS: The results of this study indicate that after construction of the ramus and condyle in type IIB and III HFM patients, vertical midface growth is secondary to a combination of midfacial and alveolar growth. Patients operated on at an older age were more likely to have a successful long-term result. Finally, the severity of the overall deformity, as reflected in a higher OMENS score, appeared to be an important factor in the response to early correction.     

Shape-coordinate analysis of skeletal changes induced by rapid maxillary expansion and facial mask therapy

The aim of this study was to evaluate maxillary and mandibular shape/size changes by means of Bookstein's shape-coordinate and tensor analysis in children with Class III malocclusions treated with rapid maxillary expansion and a facial mask in order to define optimum timing of intervention for this type of therapy. The treated group (46 subjects, 26 females and 20 males) was divided into two subgroups according to the stage of dentitional development. The early-treated group consisted of 23 subjects treated in the early mixed dentition (mean age at Time 1, 6 years 9 months +/- 7 months); the late-treated group included 23 subjects treated in the late mixed dentition (mean age at Time 1, 10 years 3 months +/- 1 year). The mean treatment period was about 11 months. The control group (32 subjects with untreated Class III malocclusion, 18 females and 14 males) also was divided into two subgroups (an early control group, 17 subjects in the early mixed dentition, and a late control group, 15 subjects in the late mixed dentition). Maxillary triangles (point T, the most superior point of the anterior wall of sella turcica, point FMN, the fronto-maxillary-nasal suture, and point A) and mandibular triangles (point Condylion, point Gonion, and point Pogonion) were digitized on cephalograms in both groups at Time 1 and Time 2. Combined facial mask and rapid maxillary expansion therapy produced a significant enhancement of the forward growth of the maxilla and significantly more upward and forward direction of growth of the mandibular condyle (leading to smaller increments in mandibular total length, Co-Pg) in the early-treated group when compared with controls and to the late-treated group. Both maxillary size and mandibular size were significantly affected by treatment in the early mixed dentition. The results of this study indicate that orthopedic treatment of Class III malocclusion induces favorable size and shape changes both in the maxilla and mandible, and that this combined treatment approach is more effective in the early mixed dentition than in the late mixed dentition.     

Classification of mandibular defects

A classification of mandibular defects based on functional as well as aesthetic factors is presented. By taking into account the difficulties in restoring form and function and not simply relying on traditional anatomic landmarks, it is hoped that this method will allow different types of reconstructions to be fairly evaluated. It also should help surgeons to tailor individual reconstructive techniques to specific clinical situations. Major difficulties in mandibular reconstruction arise when a condyle requires replacement, when there is a mucosal and/or skin component to the defect, and when the area to be reconstructed involves the anterior arch. The classification is based on three upper-case and three lower-case characters: H, C, L and o, m, s. H defects are lateral defects of any length, including the condyle but not significantly crossing the midline; L defects are the same only without the condyle; C defects consist of the entire central segment containing the four incisors and the two canines. Combinations of these letters are possible (an angle-to-angle defect, for example, is represented as LCL). Thus H and L defects may reach or even extend slightly beyond the midline but are not referred to as LC or HC unless they contain the entire central segment. The letters o (neither a skin nor a mucosal component), s (skin), m (mucosa), and sm (skin plus mucosa) are added to denote the epithelial requirement.     

Emergency center arteriography in the evaluation of suspected peripheral vascular injuries in children

During the 6-year period from 1983 to 1989, 109 children aged 3 to 18 years (mean, 16) with suspected peripheral vascular injuries underwent 113 emergency center arteriograms (ECA) performed by hand injection of contrast material using a single roentgenographic film. The most common indication for ECA was the proximity of the injury in 93 (82.3%) of the cases as penetrating injury accounted for 106 (94%) of the cases. There were 89 true-negative, 14 true-positive, 1 false-negative, and no false-positive arteriograms. The remaining 9 arteriograms were either equivocal or technically inadequate. The sensitivity, specificity, and diagnostic accuracy of this procedure were 98.9%, 100%, and 91.2%, respectively. Operative intervention was required for 9 (64.2%) injuries detected by emergency arteriography. The remaining 5 injuries were considered minor and were observed with no complications during a period of 21 months. Sixty-eight children (76.4%) with negative ECA were followed for a mean of 12 months with no vascular complications or growth abnormalities noted. ECA is a rapid, accurate, and cost-effective technique. It is of particular value in detecting the presence of occult arterial injuries that might have deleterious effects in the growing child.     

Child day care and home injuries involving playground equipment

The increasing number of children attending child day care has led to a corresponding concern for their safety in the absence of parental care. Previous studies have documented that the majority of injuries occurring in child day care involve falls, and that the most common consumer product associated with such falls is playground equipment. This study describes New Zealand children less than 5 years of age admitted to hospital between 1979 and 1988 for injuries associated with playground equipment located at home or a child care facility. There were 528 hospitalized home injuries involving playground equipment, and 145 such day care injuries. Fractures were the most common injury, and the head was the most commonly involved body region. Lower limb injuries were the most severe. Among the differences between home and day care injuries were the type of equipment involved. Swings were disproportionately associated with head injuries.     

Risk factors associated with incisor injury in elementary school children

This study examined risk factors associated with incisor injury in 3396 third and fourth grade school children in Alachua County, Florida. One of six orthodontists completed a standardized examination form for each child to assess severity of incisor injury, gender, age, race, skeletal relationships, morphologic malocclusion, incisor exposure, interlabial gap, TMJ sounds, chin trauma, and history of lower facial trauma. One in five (19.2%) exhibited some degree of incisor injury. This was limited to a single tooth in 73.1% of those with injury, while enamel injury predominated (89.4%). The majority of the injuries (75.4%) were localized in the maxillary arch, with central incisors the most frequently traumatized. Chi-square tests of association indicated that gender, race, school, orthodontist, history of lower facial trauma, chin trauma, profile, and maxillary and mandibular horizontal positions were associated with incisor injury (P < 0.05). Wilcoxon rank sum tests identified differences in age, overjet, time of screening, and interlabial gap between those with and without injury (P < 0.05). Results of logistic regression analyses indicated risk of incisor injury was greater for children who had a prognathic maxilla, a history of trauma, were older, were male, and had greater overjet and mandibular anterior spacing.     

Aspects of masticatory form and function in common tree shrews, Tupaia glis

Tree shrews have relatively primitive tribosphenic molars that are apparently similar to those of basal eutherians; thus, these animals have been used as a model to describe mastication in early mammals. In this study the gross morphology of the bony skull, joints, dentition, and muscles of mastication are related to potential jaw movements and cuspal relationships. Potential for complex mandibular movements is indicated by a mobile mandibular symphysis, shallow mandibular fossa that is large compared to its resident condyle, and relatively loose temporomandibular joint ligaments. Abrasive tooth wear is noticeable, and is most marked at the first molars and buccal aspects of the upper cheek teeth distal to P2. Muscle morphology is basically similar to that previously described for Tupaia minor and Ptilocercus lowii. However, in T. glis, an intraorbital part of deep temporalis has the potential for inducing lingual translation of its dentary, and the large medial pterygoid has extended its origin anteriorly to the floor of the orbit, which would enhance protrusion. The importance of the tongue and hyoid muscles during mastication is suggested by broadly expanded anterior bellies of digastrics, which may assist mylohyoids in tensing the floor of the mouth during forceful tongue actions, and by preliminary electromyography, which suggests that masticatory muscles alone cannot fully account for jaw movements in this species.     

Blunt abdominal trauma in children

The growing popularity of nonoperative treatment of children with splenic injuries has seduced some physicians into a false sense of security regarding care of the injured child. Although it has been established that hemodynamically stable children with splenic, hepatic, and even renal injuries can safely be treated "expectantly," this concept cannot be applied indiscriminately. Accurate diagnosis and effective care of the child with blunt abdominal trauma is an exercise of clinical precision that demands attention to detail and thorough evaluation. This review addresses this process in light of recent advances in diagnostic imaging and in consideration of recent reports analyzing different protocols for therapeutic decision making.     

Pediatric genitourinary trauma

Trauma is the leading cause of death in children in the United States, and blunt trauma is responsible in most cases. The kidney is the urogenital organ most frequently injured. Renal injuries are classified on a scale of I to V. Only grades IV and V injuries need operative intervention. CT is the preferred diagnostic imaging modality in most instances. Cystography and urethrography are necessary to diagnose bladder and ureteral injuries. Genital injuries sometimes are produced by sexual abuse, and the clinician must be alert to this possibility.     

Observations on structure of bone in human mandibular condyles with osteophyte formation

The purpose of this study was to investigate the functional characteristics of human mandibular condyles from a morphological viewpoint. The structure of bone in the human mandibular condyles with osteophyte formation was observed macroscopically and microscopically and compared with that in the condyles which seemed to be normal. The following observations were made: 1. Generally, it was observed that remodeling seemed to occur frequently in compact bone in the joint surface area of the mandibular condyle. 2. As the distribution of lamellar bone, nonlamellar, and bundle bone in the joint surface area changes, the compact bone seems to shift down and protrude forward. In larger osteophytes, trabeculae of cancellous bone-like structure are observed. However, the basic structure of compact bone, including haversian system and the interlamellae structure remains within the trabecullae. Therefore, observation revealed histologically that this is a compact bone. The macroscopical appearance of cancellous bone-like structure seems to be a result of functional demand. 4. It was concluded that the mandibular condyles accommodate the functional loads, and adoptational changes occur constantly in a stable manner.     

Hypodontia of primary and permanent teeth in a sample of Saudi children

Hypodontia, congenitally missing teeth is more common in permanent than primary dentition. The present investigation reports the prevalence and pattern of hypodontia in the primary and permanent dentitions, excluding third molars in a sample of Saudi children. The sample consists of 1,300 children, aged 5 to 10 years of age. Clinical and radiographic examinations were performed. The prevalence of children with hypodontia was found to be 2.6 percent. The mandibular second premolar was the tooth most frequently absent and account for 45 percent of the total missing teeth. In primary dentition, the maxillary lateral incisor was the tooth most frequently absent (9%). A peg-shaped permanent maxillary lateral incisor was present in 0.7 percent of the sample. Congenitally missing teeth were almost equally distributed between maxillary (52%) and mandibular (48%) arches.     

HIV risk behaviors: a comparison of U.S. Hispanic and Dominican Republic youth

Using 3-week-old male beagle dogs, we examined the cartilage-bone replacement processes in the mandibular condyle by means of light and electron microscopy. Calcification of the cartilage matrix occurred in the central area of the longitudinal septa, but not in the transverse septa. Perivascular mononuclear cells absorbed the transverse septa which initiated the opening of the chondrocytic lacunae. These cells phagocytosed septal cartilage fragments. Shortly thereafter, a thin bone layer was deposited on the remaining longitudinal septa by invading osteoblasts. Osteoclasts in lacunae developed neither ruffled borders nor clear zones in the cartilage matrix, but once the bone layer has been deposited in the remaining cartilage, these structures formed. Our results suggest that the cartilage-bone replacement in mandibular condyle involves three sequential processes: 1) degradation and phagocytosis of cartilage fragments in the transverse septa by mononuclear cells, 2) bone deposition over the remaining longitudinal septa, and 3) degradation of both calcified cartilage and bone by osteoclasts.     

When children fall

Second only to traffic accidents, accidental falling is the most significant cause of death in children. Included in this category is a special group of accidents--falling from a height--where preventative measures would give good results. Cases of child abuse have also been found in this group. From 1989 to 1994 64 children, 19 girls and 45 boys, were treated in our surgical department after accidental falls. There were 99 injuries in all, most of them caused by falls from heights less than 2.5 m. Only two children suffered penetrating injuries. Two of the 64 children died from cerebral injuries after falling from great heights. One child died from heart tamponade, caused by rupture of the right auricle after falling down a steep staircase. One child survived a fall from a great height despite multiple injuries. In such cases, treatment is dependent on a multiple trauma team being available on a 24-hour basis. Measures to prevent falls in the home, as well as in children's playgrounds and in kindergartens are not only very important, but also easy to apply. Suspicion of child abuse must be raised where unusual injuries are observed in children who have reportedly fallen from low heights.