Retrospective revelations: twenty orthodontically treated individuals with unilateral cleft lip and palate.

AIM: Twenty patients with unilateral cleft lip and palate, orthodontically treated from the full primary or early transitional dentition stages until retention and dismissal, were recalled later in adult life to evaluate the status of their occlusion and facial appearance. METHODS: Cephalometric radiographs, photographs, and casts were attained as final records. In several instances, final records were obtained by orthodontic colleagues at the patient's current residence. Evaluation of the longitudinal records provided retrospective insight pertinent to the growth and positional relationships of the jaws' contiguous structures and the dentition. RESULTS: Orthodontic results are linked with observations related to the nasomaxillary complex: the anterior cranial base, tissue deficiency, the maxillary and mandibular dentition, and time modifications in skeletal facial growth. At adult ages, the patients with unilateral cleft lip and palate had acceptable facial profiles and acceptable alignment of the anterior dentition. Variances noted in mandibular pattern of growth explain attainment of acceptable relationships. In many cases, tissue deficiency in the anterior cleft region was compensated for with fixed partial dentures and removable prosthetic appliances. Posterior crossbites, although few in number, were proportionately more prevalent in this unilateral cleft lip and palate patient population than was anticipated; possible reasons are presented, taking into consideration congenital contingencies and therapeutic overlays.

Dentoalveolar changes related to mandibular forward growth in untreated Class II persons.

The purpose of this study was to investigate dentoalveolar changes related to mandibular forward growth in persons with Class II malocclusions. The longitudinal cephalometric films of 40 subjects with untreated Class II malocclusions from mean age 8.8 to 17.8 years (before and after pubertal growth) were analyzed and compared with the Bolton norms. There was no statistically significant difference in mandibular growth between the Class II samples and the Bolton norms upon cross-sectional comparison. In the Class II subjects, forward growth of the mandible was greater than that of the maxilla by 4.36 mm on average; the dentoalveolar complex moved forward relative to the maxillary basal bone (point A) 2.16 mm and moved backward relative to the mandibular basal bone (pogonion) 2.28 mm; a strong linear relationship (almost a 1:1 ratio) existed between mandibular forward growth and dentoalveolar complex movement (r = 0.881; y = 0.976 x + 0.183). Results indicated that the effect of forward growth of the mandible, which could potentially bring the lower dentition forward, vanished into the adaptation movements of the dentoalveolar complex through intercuspal locking. Disarticulating the occlusion to minimize the effects of the adaptive mechanism and taking advantage of normal mandibular forward growth could be fundamental biological bases in treating Class II malocclusions in growing patients.

Cranial base and facial skeleton asymmetries in individuals with unilateral cleft lip and palate.

OBJECTIVE: Individuals with unilateral cleft lip and palate (UCLP) manifest a plethora of phenotypic characteristics, including asymmetric development of the middle and lower facial skeleton. The purpose of this study was to retrospectively investigate the development of cranial base asymmetries in patients with UCLP noted on posteroanterior cephalometric radiographs. METHODS: Thirty individuals with UCLP and 64 controls participated in this study. Medial and lateral cranial base asymmetries were analyzed on frontal cephalometric radiographs relative to three developmental stages. Furthermore, the development of horizontal and vertical lower facial asymmetry in these patients with UCLP was assessed in relation to cranial base, nasomaxillary, and dentoalveolar structures. RESULTS: Individuals with UCLP demonstrated cranial base asymmetries that did not significantly differ from individuals without cleft. In addition, lower facial asymmetry in patients with UCLP correlated with horizontal lower facial and dentoalveolar asymmetries but not with cranial base or nasomaxillary structures. CONCLUSIONS: No significant vertical cranial base asymmetries were detected in patients with UCLP. Horizontal lower facial asymmetry appeared to develop in close relation to the vertical asymmetries of mandibular fossae and dentoalveolus.

Nonsteroidal anti-inflammatory drugs in orthodontic tooth movement: metalloproteinase activity and collagen synthesis by endothelial cells.

Orthodontic treatment is based on the biologic principle that prolonged pressure on teeth results in remodeling of periodontal structures, allowing for tooth movement. Periodontal remodeling is a complex process regulated in part by prostaglandins and adversely affected by the use of nonsteroidal anti-inflammatory drugs. We investigated the effects of indomethacin on collagenase activity and procollagen synthesis in rat endothelial cell cultures. Cyclooxygenase inhibition resulted in exacerbation of IL-1 beta-mediated collagenase B (MMP-9) production and activity, as well as attenuation of type IV procollagen synthesis levels by endothelial cells in vitro. Hence, the use of over-the-counter nonsteroidal anti-inflammatory drugs during tooth movement may result in aberrant remodeling of periodontal vasculature and other structures, ultimately affecting orthodontic treatment efficacy. Further studies are needed to establish novel pain relievers that do not interfere with orthodontic processes.

Mandibular asymmetry in noncleft and unilateral cleft lip and palate individuals.

OBJECTIVE: The purpose of this study was to retrospectively investigate mandibular asymmetry in unilateral cleft lip and palate individuals (UCLP) in relation to chronologic age and in relation to lower facial asymmetry. DESIGN: The longitudinal records of 34 UCLP individuals and 142 controls treated in the Department of Orthodontics, Eastman Dental Center, Rochester, NY, were included in the study. Posteroanterior and oblique cephalometric radiographs were analyzed for lower facial asymmetry and mandibular asymmetry, respectively. Mandibular asymmetry in UCLP was analyzed relative to three age groups (6-10, 11-14, and 15 or greater) and compared to controls. Moreover, mandibular asymmetry was analyzed relative to lower facial asymmetry. RESULTS: UCLP individuals showed no significant differences in mandibular asymmetry compared to controls. In addition, no significant correlation was found between mandibular asymmetry and lower facial asymmetry in UCLP. CONCLUSIONS: The degree of mandibular asymmetry in UCLP appears not to be the major contributing factor to the lower facial asymmetry noted on these individuals. Possible cranial-base/temporal-region anomalies may be involved in unilateral cleft lip and palate and be responsible of the asymmetry noted in the lower facial skeleton.

Mandibular and maxillary asymmetry in individuals with unilateral cleft lip and palate.

OBJECTIVE: This study was conducted to evaluate the degree of maxillary and mandibular asymmetry in the verticle and transverse planes seen in posteroanterior cephalometric radiographs relative to chronologic age in postoperative complete UCLP patients compared to controls. METHOD: Mandibular and nasomaxillary asymmetry was retrospectively studied in complete unilateral cleft lip and palate (UCLP) and noncleft individuals (controls) by means of posteroanterior cephalometric analysis. All the UCLP patients available (total 40) and randomly selected noncleft controls (total 142) were included in the study. The UCLP patients had undergone lip and palate reconstruction in Strong Memorial Hospital, University of Rochester, Rochester, New York, and orthodontic treatment in the Department of Orthodontics, Eastman Dental Center, Rochester, New York. The controls were selected based on the age that treatment was initiated and were treated in the department for various malocclusions; none had undergone maxillary expansion or surgical treatment. The asymmetry assessed on mixed longitudinal records of the patients with UCLP was analyzed relative to three chronologic age groups and compared to the controls. In addition, mandibular asymmetry was correlated to maxillary asymmetry in UCLP individuals to investigate possible growth patterns between the two jaws. RESULTS: Mandibular asymmetry in UCLP individuals was found to increase with growth and time and peaked at post-pubertal growth-spurt stages. The cleft subjects were more asymmetric than controls in all stages of growth. Mandibular asymmetry followed the affected maxilla closely, indicating a parallel growth pattern of the jaws. CONCLUSION: The unilateral cleft lip and palate patients manifested asymmetry of the mandible. This asymmetry develops in a parallel pattern with the affected maxilla, suggesting that early evaluation and treatment of the anomalies in the nasomaxillary skeleton as well as in the mandible is necessary when treating unilateral cleft lip and palate individuals.

Effect of a surgically created disk displacement on mandibular symmetry in the growing rabbit.

PURPOSE: The purpose of this study was to evaluate the contribution of unilateral disk displacement to growth changes in the young New Zealand White rabbit. METHODS: Ten female rabbits aged 10 weeks were included in this study. The five experimental rabbits had unilateral anterior disk displacement surgery. The five controls had no surgery. The rabbits were killed at 22 weeks of age, and the mandibles hemisected and radiographed. Cephalograms were digitized and analyzed by conventional methods. RESULTS: The gross appearance showed shortening and flattening of the articulating surface in the experimental group (P < 0.05). No significant shortening and flattening was found in the control group. CONCLUSION: These observations suggest that surgically created internal derangement can produce altered growth in the mandible.

Asymmetries of the upper lip and nose in noncleft and postsurgical unilateral cleft lip and palate individuals.

The purpose of this study was to retrospectively evaluate post-surgical asymmetries of the upper lip and nose in complete unilateral cleft lip and palate individuals using documentation collected over a period of years. Twenty-three complete unilateral cleft lip and palate subjects (UCLP) and 34 noncleft subjects who served as controls and had undergone orthodontic treatment were included in the study. Nasal asymmetry, deviation of the tip of the nose, and the deviation of the midpoint of the vermilion border of the upper lip were compared to chronologic age and skeletal maturation in cleft subjects and controls. Comparison between cleft and control cases was also assessed. Results indicate that nasal asymmetry peaks at postpubertal growth stages in the control groups, and the difference between UCLP and controls decreases with time and maturation. The deviation of the nasal tip peaks during the pubertal growth spurt for both UCLP and controls, and the difference between UCLP and controls also decreases with time. The deviation of the midpoint of the vermilion border shows relatively small change with time and maturation, and there is no significant difference between UCLP and controls. In general, the facial asymmetries studied were not as great as expected, and the difference between UCLP and controls decreased with time, growth, and maturation.

Skeletal asymmetries of the nasomaxillary complex in noncleft and postsurgical unilateral cleft lip and palate individuals.

Asymmetries in the nasomaxillary skeleton are very common in individuals with unilateral cleft lip and palate. The purpose of this study was to retrospectively evaluate postsurgical asymmetries of the nasomaxillary skeleton in unilateral cleft lip and palate patients. Included in this study were 36 complete cleft lip and palate subjects, along with 36 noncleft (control) subjects. Skeletal asymmetry, deviations of the anterior nasal spine, and the premaxillary area were compared by chronologic age and skeletal maturation in cleft subjects and controls. Comparison between cleft and control cases was assessed. Results indicated that skeletal asymmetry in unilateral clefts and controls peaks during the pubertal growth spurt. The anterior nasal spine and nasal septum always tend to deviate toward the noncleft side of the nasal cavity, although individual variation exists. Cleft subjects were found to be more asymmetric than noncleft subjects to a statistically significant degree.

Spectral study of deviant resonance in the speech of women who are deaf.

In a previous radiographic study of 4 deaf women, some aberrant features in vocal tract configuration were identified for vowels produced with excessive pharyngeal resonance. These features included neutralization of tongue position, elevation of the hyoid, and a retraction of the tongue, associated with a deflection of the epiglottis in the lower pharynx. The vowels, produced simultaneously with X-ray exposure, were analyzed spectrographically to study acoustic correlates of the vocal tract deformation. Comparisons of the formants for vowels /i/ /u/ and /a/ produced by the deaf women with mean formant values for these vowels produced by normal-hearing women revealed no consistent pattern of second-formant deviation. Formant structure evaluated on isovowel lines disclosed consistent neutralization of vowels, with F2 values clustering in the 1500-2100 Hz frequency range, which is attributed to the observed restricted horizontal movements of the tongue within the oral and pharyngeal cavities. If such restrictions affect the production of all vowels, a lower F2 might be assumed for the front vowels, which normally have a high F2; a higher F2 frequency would be anticipated for back vowels, which normally have a low F2. The limited sample studied supports this assumption.

Facial growth during adolescence in early, average and late maturers.

The relative stage of maturity of a child may be determined by comparing the child's hand-wrist radiograph to known standards of skeletal development. Hand-wrist radiographs of 70 adolescents were used to categorize the individuals by skeletal maturation into early, average and late maturation groups using the Fishman SMA method of assessment. The rates of mandibular and maxillary growth relative to the last stages of the pubertal growth spurt were measured. Statistical evaluation of the data was performed using an analysis of variance. The magnitude of change in growth increments of the mandible was greater in the late maturers than in the early or average maturers. Incremental differences in growth between the maxilla and mandible during the last stages of puberty were noted, with the mandible growing significantly more than the maxilla.

An American Board of Orthodontics case report. Correction of a Class III mandibular prognathism and asymmetry through orthodontics and orthognathic surgery.

The Class III malocclusion with mandibular prognathism can involve many factors, among which are excessive mandibular growth, underdevelopment of the maxilla, environmental factors, and trauma to the jaws. The correction of this malocclusion can involve an orthodontic or a combined orthodontic-orthognathic approach. Skeletal asymmetries can complicate this situation, making treatment either more difficult, more complicated, or both. This case presentation involves treatment with a combined orthodontic-orthognathic approach. [This case was presented to the American Board of Orthodontics in partial fulfillment of the requirements for the certification process conducted by the Board.]

CT density of the TMJ disk: correlation with histologic observations of hyalinization, metaplastic cartilage, and calcification in autopsy specimens.

The attenuation number of the TMJ disk was measured in direct sagittal computerized tomograms (CTs) of eight fresh TMJ autopsy specimens. The CT attenuation number was correlated to histologic observations of hyalinization, calcification, and cartilaginous metaplasia of the disk. Correlations were found between high CT attenuation numbers and the presence of hyalinization, calcification, and foci of cartilaginous metaplasia in the disks. The results suggest that the high CT attenuation number of a disk might be associated with hyalinization, calcification, and metaplastic cartilage formation.

Cephalometric and cineradiographic study of deviant resonance in hearing-impaired speakers.

To study physiological basis for deviant resonance in hearing-impaired speakers, cephalometric roentgenography and cineradiography were applied to analyze oral/pharyngeal relationships during vowels produced in isolation and within a sentence context. The films, synchronized with sound recording, were traced and measured for 10 normal hearing and 4 hearing-impaired women with deviant resonance. Vocal tract conformations and dimensions were defined by measures of the lips, tongue, mandible, velum, hyoid bone, epiglottis, and laryngeal sinus. Means, standard deviations, and analyses of variance were applied to facilitate descriptions and comparisons between the groups. The hearing-impaired speakers had near normal lip openings for /i/ and /u/ but more open positions for /a/. The tongue tended to retract for the front vowel and front for the back vowel /u/. For high vowels, most of the hearing-impaired speakers had an elevated hyoid, an unusually large vertical dimension between hyoid and laryngeal sinus, and a retracted tongue root, which was associated with a marked retraction or deflection of the epiglottis toward the pharyngeal wall. The cine analysis of the normal hearing speakers showed rather well defined and consistent shifts in tongue position for the front vowels produced in the sentence context. The hearing-impaired speakers with deviant resonance showed greater variation among speakers in tongue body position and a significant retrusion of the dorsum of the tongue at a site significantly lower than observed in hearing speakers. The consistent tongue root retraction during static as well as dynamic speech production is interpreted as support for Boone's hypothesized cause of pharyngeal resonance in speech of the hearing impaired.

An American Board of Orthodontics case report. Orthodontic treatment of a patient born with a severe right unilateral cleft lip and palate.

The patient was born with a severe cleft of the right lip, alveolus, and palate. After surgical correction of these defects at a very young age, the patient began a 6-year period of active orthodontic treatment at the Eastman Dental Center. With the cooperation of the patient and his parents, successful results, both dentally and skeletally, have been achieved. The treatment results have been stable during the 3-year period following the initial placement of retention. The postretention records show a molar relationship within normal limits and some return of the original spacing located in the mandibular anterior segment. The bonded "Maryland bar" is still in place and the cast single-tooth partial is still being used. At the proper time, a fixed permanent bridge is planned.

An American Board of Orthodontics case report. Correction of a severe Class II malocclusion.

Many factors often combine to create a malocclusion. Broadly these include the genetic potential of the individual and environmental or local factors. Class II, Division 1 malocclusions may result from both inherited skeletal and dental patterns and an additional environmental factor such as thumb sucking or some other habit. Successful treatment of patients with this type of malocclusion requires both an orthodontic correction of the existing dental and skeletal problems and also control of any deleterious habit. The following case report deals with a patient who had such a malocclusion.

An American Board of Orthodontics case report. A combined face mask-orthognathic surgical approach in the treatment of skeletal open bite and maxillary deficiency.

This case report is presented following the specifications of the American Board of Orthodontics. The patient had a true skeletal open bite with maxillary and mandibular asymmetry. She was treated with an orthognathic surgical approach and face mask therapy to stabilize the postsurgical result.