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Biomedical subjects

B Solow

Publications and source records attributed to B Solow.

At least 37 records · Page 2Linked to original sources
PubMed1992

Cervical and craniocervical posture as predictors of craniofacial growth.

The present study aimed to determine whether growth changes in craniofacial structure could be predicted by variables expressing the postural relations of the head and the cervical column. The sample comprised 34 children, 16 girls and 18 boys. Cephalometric radiographs obtained in natural head position (mirror position) were taken on two occasions before orthodontic treatment. Mean age was 9.9 years at time 1 and 12.7 years at time 2. Selection of the sample was based on skeletal maturity at time 2 indicating peak activity in pubertal growth. Forty-one reference points and four fiducial points were digitized on each film. Individual growth changes in craniofacial structure were determined by computerized structural superimposition of the digitized sets of points. Correlation coefficients were calculated between 11 postural variables at the first observation and the subsequent growth rate in 36 structural variables. Uniform fields of low to moderate correlation coefficients significant at the 5%, 1%, and 0.1% levels (0.3 to 0.6) were found for eight structural variables, indicating that a small craniocervical angle and a backward-inclined upper cervical column at time 1 was associated with horizontal facial development characterized by reduced backward displacement of the temporomandibular joint (TMJ), large maxillary growth in length, increased facial prognathism, and larger than average true forward rotation of the mandible; whereas, a large craniocervical angle and an upright position of the upper cervical column at time 1 was associated with vertical facial development characterized by large backward displacement of the TMJ, reduced growth in length of the maxilla, reduced facial prognathism, and less than average true forward rotation of the mandible. The findings are in agreement with a theoretical model for the developmental interaction between head posture and facial structure.

Cephalometry↗
PubMed1991

Nasal airflow characteristics in a normal sample.

The present study aims to describe the characteristics of nasal airflow in terms of the relative contributions of laminar and turbulent flow to the total pressure drop across the nose. The sample comprised 20 dental students with no history of nasal airway obstruction. Rhinomanometric data were recorded by a Mercury NR6 rhinomanometer with a Rohrer programme by the anterior and posterior methods after decongestion. Rohrer equation coefficients were calculated for each respiratory cycle. Method errors ranged from 6.3 to 9.3 per cent of sample variances. At a threshold of 75 Pa, average unilateral NAR was about 300 Pa/l/s and average bilateral resistance about 250 Pa/l/s. Analysis of the Rohrer equation data showed average coefficients of laminar (k1) and turbulent (k2) flow of 113 and 807 in unilateral breathing, indicating a predominance of turbulent flow. In bilateral breathing a switching of airflow characteristics occurred, with k1 and k2 coefficients of 147 and 348 indicating a marked reduction in the turbulent component of flow. It is suggested that Rohrer equation coefficients might provide information about nasal airflow which are physiologically more meaningful than conventional resistance calculations based on a single point on the rhinomanometric pressure-flow curve.

Adult↗
PubMed1991

Age differences in adult dentoalveolar heights.

A previous study of age differences in facial morphology in a dentate sample representing young, middle, and old age (Tallgren and Solow, 1987) indicated an increase in lower anterior face height during adulthood. The aim of the present study was to examine in detail the accompanying age differences in dentoalveolar heights. The material consisted of lateral head films of 191 dentate Finnish women divided into the age groups 20-29, 30-49, and 50-81 years. The present study comprised 26 variables calculated from digitized reference points. The maxillary and mandibular anterior dentoalveolar heights were significantly larger in the middle and old age groups than in the young group, and the mean differences were of the same magnitude for the maxilla and the mandible. Analysis of the dentoalveolar components showed that in the mandible the extra-alveolar height of the incisors was significantly larger in the two older age groups than in the young group, while no significant differences were found in the maxilla. The mean differences in anterior mandibular ridge height between the older age groups and the young group were smaller than in the maxilla. No significant differences in dentoalveolar morphology were observed between the middle and the old age groups.

Adult↗
PubMed1991

Linearity of cephalometric digitizers.

The present study aimed to develop a test procedure to diagnose and visualize errors in linearity of digitizing tablets. Errors of linearity are caused by the distortion of the x- and y-co-ordinates of the digitizing tablet. This results in a given object apparently having different dimensions when recorded on different locations of the digitizing surface. The test is performed by systematic recording of n equally spaced points from a calibrated test foil. Algorithms were developed to calculate the difference matrices DXji and DYji between expected and observed values of the co-ordinates. Three-dimensional mapping of the non-linearity of the x- and y-co-ordinates was performed by the UNIRAS-geopak, a 3-D surface representative system. The tested digitizers showed varying degrees of scaling errors, fields of non-linearity, and random noise. Most digitizers allow for correction of scaling by setting of switches in the control unit. A method is suggested for correction of non-linearities by use of the DXji and DYji matrices in the digitizing programme.

Algorithms↗
PubMed1991

Nasal airway resistance in the newborn.

The present study aimed to provide normative data for nasal airway resistance in the newborn. Anterior rhinomanometry was performed on 17 full term Caucasian infants aged 1 to 4 days, birthweight 3100 to 4150 g. No sedation or decongestion was performed. Average unilateral nasal resistance was 4.86 kPa/l/s (SD = 2.41) at a pressure threshold of 75 Pa. Average nasal resistance calculated from the right and left side recordings was 2.14 kPa/l/s (SD = 0.77). This corresponds to 21.8 cm H2O/l/s (SD = 7.9). The nasal resistance of the newborn thus is approximately 10 times that of the adult.

Airway Resistance↗
PubMed1990

Influence of skin graft pathology on residual ridge reduction after mandibular vestibuloplasty. A 5-year clinical and radiological follow-up study.

The present study is a 5-year clinical and radiographic follow-up of 51 patients who had undergone a combined vestibuloplasty with a split skin graft and lowering of the floor of the mouth. Our purpose was to examine the effect of clinically evident graft pathology on the residual ridge reduction. The clinical records of the graft condition were classified into: healthy graft, partial loss of keratinization, and total loss of keratinization. The residual ridge reduction was monitored by ridge height measurements at different locations, and by the symphyseal and mandibular body areas. Patients with clinical signs of graft pathology (reddening, loss of keratinization) suffered a significantly more severe residual ridge reduction than those with a healthy skin graft (p less than 0.01). Subsequent findings including smear tests showing Candida albicans hyphae, and improvement of graft condition after antimycotic therapy, indicated that the graft pathology observed is a candidiasis.

Adult↗
PubMed1990

Soft tissue profile changes after mandibular vestibuloplasty. A two-year follow-up study comparing the Edlan flap, mucosal and skin graft methods.

It is the aim of the present study to examine the pattern of postoperative changes in the soft tissue profile of 50 edentulous patients after 3 common types of mandibular vestibuloplasty, the Edlan flap operation (n = 15), the buccal mucosal graft (n = 19), and the skin graft vestibuloplasty (n = 16). The soft tissue profile changes were recorded on lateral cephalometric radiographs taken preoperatively, and after 1, 3, 6, 12, and 24 months post surgery. The 3 groups did not differ with respect to clinical features or presurgical cranio-facial morphology. Neither was any significant difference in postoperative profile changes found between the groups. The surgery gave rise, directly and indirectly, to a number of changes in the facial soft tissue profile many of which were interrelated. The chin thickness increased by 2.3 mm, and the lower lip height exhibited a reduction of 1.8 mm at 1 month after surgery as a direct consequence of the operation. After 3 months the profile changes were mostly associated with the reduction of the anterior face height (overclosure).

Adult↗
PubMed1990

Growth displacement of the maxilla in girls studied by the implant method.

The sutural growth displacement of the maxilla between the ages of 8 and 21 years was studied on 14 series of lateral cephalometric films of girls from the Björk implant sample (Björk 1968). The assessment of growth changes was based on the method of superimposition described by Björk and Skieller (1983) supplemented by a new computerized debugging procedure. A new method for angular measurement of the forward displacement of the maxilla and the mandible is described here. The average forward displacement of the maxilla in relation to the anterior cranial base was 6 degrees from 8.5 to 17.5 years. The average path of displacement was inclined about 45 degrees in relation to the nasion-sella line from 8.5 to 14.5 years, and then changes to almost horizontal. The mean distance between anterior and posterior implant points showed a continuous shortening, totalling 0.6 mm for the period 8.5 to 15.5 years, due to maxillary rotation in the transverse plane. The timing of growth differed between the horizontal and vertical components of the maxillary growth translation. Horizontal displacement peaked at 11 and terminated at 18 years, whereas vertical displacement peaked at 12 and terminated at 15 years of age.

Adolescent↗
PubMed1989

Reduction of mandibular residual ridge after vestibuloplasty. A two-year follow-up study comparing the Edlan flap, mucosal and skin graft operations.

Mandibular residual ridge reduction (RRR) after Edlan flap vestibuloplasty, buccal mucosal graft, and split skin graft vestibuloplasty was measured on lateral cephalometric radiographs obtained 1, 3, 6, 12 and 24 months postsurgery in 50 patients. The ridge reduction was most severe during the immediate postoperative period. The different operation methods did not give rise to significant variations in the reduction pattern, neither did the sex of the patient appear to be an important factor. The temporary increase of mandibular resorption after vestibuloplasty surgery is of a magnitude comparable to the average RRR during 1 year in full denture wearers with a long denture experience.

Aged↗
PubMed1989

Alveolar bone loss and crowding in adult periodontal patients.

The present study aimed to examine whether local crowding and tooth angulation in the mandibular incisor region led to alveolar bone loss in patients with moderate periodontal disease. The sample comprised 27 patients from the Department of Periodontology aged 29-57 yr. Mesiodistal tooth angulation and crowding, defined as an overlap of 2 mm or more, were assessed from dental casts. Alveolar bone loss was assessed from intraoral standardized paralleling radiographs by two methods, the absolute bone level (ABL), recorded from the cementoenamel junction, and the relative bone level (RBL), a new measure, expressing the bone level relative to the two adjacent interradicular crests. Contralateral sites were used as controls. A significant difference in bone level was found between crowded and non-crowded sites by both methods (-1.7 mm, P less than 0.001). This indicates that in periodontal patients local crowding and tooth angulation predisposes to increased bone loss. Analysis of the correlations between tooth angulations and the two measures of bone loss indicated that the RBL value is a more sensitive measure of localized bone loss.

Adult↗
PubMed1987

Nasal respiratory resistance in cleft lip and palate.

The present study aimed to determine the nasal respiratory resistance (NRR) in subjects with cleft deformity of the lip and palate. The cleft sample was subdivided into cleft lip (N = 15) (mean age 13.4 years, median age 14 years), cleft palate (N = 19) (mean age 12.7 years, median age 12 years), and unilateral cleft lip and palate subjects (N = 27) (mean age 16.4 years, median age 16 years). A control group consisted of 38 patients (mean age 14.4 years, median age 12 years) attending for orthodontic diagnosis. Respiratory resistance was determined by a Mercury rhinomanometer, which was calibrated dynamically before each session. Subjects were given 0.1% xylometazoline hydrochloride half an hour before each session. Resistance was determined unilaterally by the anterior method as well as bilaterally by the posterior method. The results showed that the bilateral nasal resistance did not differ significantly between the cleft samples and the controls. Unilateral measurements of nasal resistance showed higher values for the cleft side than for the noncleft side, both in the cleft lip (CL) and the unilateral cleft lip and palate (UCLP) samples (p less than 0.001). In the cleft palate sample as well as in the controls, unilateral nasal resistance did not differ between the two sides.

Adolescent↗
PubMed1986

Growth changes in head posture related to craniofacial development.

Cross-sectional studies have demonstrated an association between craniocervical angulation and craniofacial morphology. It was the aim of the present study to determine if the growth coordination suggested by this association could be detected in a longitudinal analysis of growth changes in posture and craniofacial morphology. The sample comprised 43 children, 20 girls and 23 boys. Cephalometric radiographs obtained in the natural head position (mirror position) were taken on two occasions. Mean age at the first observation was 9.5 years; mean period of observation was 2.7 years with a range from 1 to 4 years. Forty-one reference points and four fiducial points were digitized on each film. Individual growth changes were determined by computerized structural superimposition of the digitized sets of points. Correlation coefficients were calculated between growth changes in 11 postural and 35 morphologic variables. Correlations of r = 0.41-0.55 (P less than 0.01) were found between the change in craniocervical angulation and the true growth rotation of the mandible as assessed by the method of structural superimposition. On the average, a reduction of the craniocervical angle was seen in connection with increased forward rotation of the mandible and an increased craniocervical angle was found in conjunction with a less-than-average forward rotation of the mandible. The true mandibular rotation was masked by remodeling of the lower mandibular border. The changes in the conventional measures of head posture--the craniovertical angles--during the observation period showed no associations with the growth changes in craniofacial morphology.

Cephalometry↗
PubMed1986

Craniocervical postural relations and craniofacial morphology in 30 blind subjects.

Previous studies have shown that head posture is dependent on vision. The head posture of blind persons therefore can be expected to differ from that of normal subjects. This is of interest in the current analyses of the relation between head posture and craniofacial morphology. The purpose of the present investigation was to describe the posture of the head and cervical column and the craniofacial morphology in a group of blind subjects, and to compare the findings with those previously found in male and female groups of normal subjects. The sample comprised 30 blind subjects--18 men and 12 women, aged 15 to 35 years, all of whom had been without perception of light since birth. The control group comprised 120 male dental students in the age range 22 to 30 years and 51 female dental students in the age range 22 to 27 years. The analysis of head posture showed that the intra-and interindividual variabilities of the craniovertical angles were significantly larger than those of the craniocervical angles in the blind group. The interindividual variabilities of the craniovertical angles were significantly larger in the blind than in the control group, but the variabilities of the craniocervical angles were similar in both groups. Craniovertical relations thus were more variable in the blind subjects, whereas craniocervical relations showed the same variability as normal subjects. On the average, the head was carried in a 4.3 degrees lower position in the neck was 4.5 degrees more forward inclined in the blind group. No differences were found in the position of the head in relation to the cervical column between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1986

Effect of separate malocclusion traits on concern for dental appearance.

Effects of separate traits of malocclusion on concern for dental appearance were isolated by means of multiple regression analysis in a 15-yr follow-up study of 30-yr-old Danes. On the basis of questionnaires (response rate 86%, n = 841), the dependent "concern-for-dental-appearance" variable was constructed from the respondents' replies about recalled perceptions and societal reactions concerning their dental appearance at the time of adolescence. In the same individuals, separate traits of malocclusion had been recorded clinically 15 yr earlier. These traits were inserted as independent dummy variables into the regression model. In both sexes the closest relationship with the dependent variable was displayed by the most conspicuous traits in the anterior region of the dentition. Some traits showed significant associations only in women, whose regression coefficients were, in general, higher than those of men. About half of the variation in the dependent variable was explained by the model.

Adult↗
PubMed1985

Psychosocial implications of malocclusion: a 15-year follow-up study in 30-year-old Danes.

Long-term psychosocial effects of malocclusion should be studied longitudinally from childhood to adulthood in orthodontically untreated populations. In 1965-66, the occurrence of morphologic traits of malocclusion was recorded in 977 Danish adolescents who had no access to organized orthodontic care. In a follow-up study 15 years later, a questionnaire was mailed to the subjects; this contained general questions about body image and specific inquiries concerning self-perception and social implications of dental appearance. The response rate was 86%. Ten percent had received orthodontic treatment. In the remaining individuals, only one entry among thirteen items of body image--the teeth--was rated significantly less satisfactory by subjects with malocclusion at adolescence than by subjects without malocclusion at adolescence. The lowest ratings were observed in subjects with extreme maxillary overjet, extreme deep bite, and crowding. Highly significant differences were found between the two groups (subjects with and without malocclusion) in recalling adolescent awareness of malocclusion, dissatisfaction with the appearance of the teeth, and unfavorable appearance of the teeth compared with those of peers. Schoolmates' teasing occurred seven times more often in the presence of malocclusion. Differences were less marked in the perceptions of the same individuals in adulthood. However, in both adolescence and adulthood unfavorable perceptions of the teeth were expressed significantly more often by subjects with extreme maxillary overjet, extreme deep bite, and crowding. No association was found between malocclusion and present occupational status. It was concluded that certain malocclusions, especially conspicuous occlusal and space anomalies, may adversely affect body image and self-concept, not only at adolescence but also in adulthood.

Adolescent↗