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Biomedical subjects

J D Subtelny

Publications and source records attributed to J D Subtelny.

At least 37 records · Page 2Linked to original sources
PubMed1989

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.

Adult↗
PubMed1988

Long-term periodontal status after orthodontic treatment.

This study evaluated the clinical periodontal status of persons who had completed orthodontic therapy at least 10 years previously (study) and compared the findings to those of adults with untreated malocclusions (control). Subjects in the study (n = 112; 63 female subjects, 49 male subjects; mean age 29.3 +/- 4.2 [SD] years) and control (n = 111; 62 female subjects, 49 male subjects; mean age 32.9 +/- 6.5 years) populations underwent a comprehensive periodontal examination that consisted of measurements taken at six points around the circumference of each tooth: (1) plaque, (2) visual inflammation, (3) bleeding after probing, (4) pocket depth, (5) gingival recession, and (6) loss of connective tissue attachment. Data from the individual measuring points were organized into 14 different combinations of either tooth types or surface locations; each was subjected to a four-way ANOVA partitioned on group (study vs. control), sex, socioeconomic status, and malocclusion type. The results showed that differences in age distribution within the groups were affecting the comparisons between the groups. Consequently, the groups were balanced for age and analyses were done to investigate group differences by means of multiple regression techniques. The comparisons showed no significant differences between the groups for any of the periodontal variables. It was concluded that orthodontic treatment during adolescence had no discernible effect upon later periodontal health.

Adult↗
PubMed1987

Orthodontic relapse, apical root resorption, and crestal alveolar bone levels.

This investigation examined the relationship of postorthodontic treatment relapse to crestal alveolar bone support and root resorption. Thirty-six persons having completed the retention phase of orthodontics at least 10 years earlier were divided into two groups based on the amount of relapse crowding of the mandibular anterior teeth. Eighteen subjects (relapse group) exhibited 2 mm or more of mandibular anterior relapse crowding and 18 subjects (nonrelapse group) exhibited no mandibular anterior relapse crowding. At time of recall, full-mouth series of periapical and bitewing radiographs were obtained as well as lateral cephalometric films to allow comparison with similar lateral cephalometric films obtained at pretreatment and retention time points. The radiographs were examined to assess three parameters: root resorption, crestal alveolar bone levels, and changes in the position and angulation of the maxillary incisors. The subjects in the relapse group had undergone longer periods of treatment and exhibited a greater prevalence of root resorption; they also displayed significantly greater crestal alveolar bone level distances, indicating greater loss of bone support than that observed in the nonrelapse group. The distances that teeth were translated seemed to affect the extent of root resorption and crestal bone loss with smaller amounts of tooth translation seemingly more prone to demonstrate tissue loss. The findings of this investigation suggest there may be a relationship between orthodontic relapse and the parameters of increased root resorption and decreased crestal alveolar bone levels.

Adult↗
PubMed1985

Long-term periodontal status of teeth moved into extraction sites.

The present study was undertaken to assess the long-term periodontal status adjacent to teeth that had been moved orthodontically into extraction sites. Twelve persons with a mean age of 29.2 +/- 5.7 (SD) years, who had completed orthodontic therapy at least 10 years previously, were examined. The orthodontic treatment had included bilateral premolar extraction in only the maxilla. Interproximal tooth surfaces in the maxilla adjacent to the extraction sites (study group) were compared to corresponding tooth surfaces in the mandible (control group) with respect to plaque, visual inflammation, bleeding after probing, pocket depth, gingival recession, loss of connective tissue attachment, radiographic bone height, and root resorption. Statistical comparisons were made via analyses of variance and t tests. There were no differences between the groups for any clinical parameter except the presence of less visual inflammation in study subjects. Radiographically, there were no differences in crestal alveolar bone levels measured from the cementoenamel junction. Bone height evaluation by the Bjorn method showed less alveolar support in the study group. However, this was due to the influence of root resorption rather than an effect on crestal height. It was concluded that orthodontic movement of teeth into extraction sites had been without detrimental effect upon the adjacent periodontal status.

Adult↗
PubMed1985

The degenerative, regenerative mandibular condyle: facial asymmetry.

Studies of longitudinal cephalometric radiographs are presented for several patients with condylar fracture or hemifacial microsomia to illustrate condylar regeneration, presumably under functional influences. Implications of new condylar development and growth to facial and mandibular symmetry are presented. Clinical implications are introduced and the hypothesis of necessity of function for maintenance of relative facial symmetry is considered.

Bone Regeneration↗
PubMed1983

Eruption of incisor teeth in cleft lip and palate.

Longitudinal frontal and lateral cephalometric radiographs were used to study the path of eruption of the permanent central incisors approximating the cleft areas in 15 subjects with unilateral and 7 subjects with bilateral complete clefts of the lip and palate, aged between 3 years 8 months and 9 years. Tracings from the longitudinal transparent templates of the Bolton Standards subjects were used as controls for comparative purposes. The findings indicate that the pattern of eruption of the maxillary central incisor follows the pattern of alveolar development in the cleft subjects. The position of the premaxilla subsequent to cleft repair influences the eruption pattern of the maxillary central incisors approximating the cleft areas. The central incisors erupt down and back, and become more retroclined and retropositioned within the nasomaxillary complex, with increment in age. The crowns of the central incisors approximating the cleft in unilateral cleft lip and palate subjects progressively tipped more towards the cleft with age.

Cephalometry↗
PubMed1979

Description and evaluation of structured speaking and listening activities for hearing-impaired adults.

This study was designed to evaluate improvement in word comprehension, pronunciation, and auditory discrimination as a result of structured group experience in speaking and listening. Subjects included 75 college students with hearing impairment and auditory discrimination for speech. Subjects were divided into three groups matched on the basis of hearing characteristics. Groups A and B received 20 hours of instruction over a 10-wk interval. Group A was evaluated relative to word comprehension, word usage in writing, and pronunciation. Group B was evaluated relative to auditory discrimination before and after training. Group C (control) did not receive training but auditory discrimination was evaluated over the 10-wk interval. Significant improvements in word comprehension, word usage in writing, pronunciation, and in auditory discrimination were achieved as a result of training. No significant change in auditory discrimination was observed in the control group.

Adult↗