Pubertal Growth Period Research Articles

Changes in dentoalveolar and facial heights during early and late growth periods: a longitudinal study.

This longitudinal study examined the dentoalveolar structures during early and late growth periods in 62 subjects (26 male, 36 female) with normal facial patterns and acceptable occlusions. Hand-wrist radiographs were assessed and subjects grouped accordingly as either early stage (group 1) or late stage (group 2). Group 1 comprised 30 subjects with skeletal development maturation stages between PP2= and MP3=, H or S. Group 2 comprised 32 subjects with skeletal development maturation stages between MP3u and Ru. Skeletal and dentoalveolar measurements and ratios were assessed at the beginning and end of the observation periods. Differences in measurements and ratios within each group were examined using paired t-tests. Differences between the 2 groups were evaluated using Student's t-tests. Increases in alveolar heights (except for upper posterior alveolar heights) differed between the groups. Vertical alveolar dimensions increased substantially in group 1 in comparison with group 2. With the exception of upper anterior alveolar heights, all increases in group 2 were statistically significant. As a result of differential growth in alveolar dimensions, lower facial ratio (Co-Go/ANS-Me) and overbite remained constant in both stages. Vertical alveolar growth exhibited regional differentiation according to the pubertal growth periods. Although this growth plays a role in the establishment of normal facial patterns and occlusion, it should also be considered with respect to the treatment and treatment stability of patients showing vertical facial discrepancies.

Molar Changes with Cervical Headgear Alone or in Combination with Rapid Maxillary Expansion

To test the hypothesis that there is no difference in the distal movement of the maxillary first permanent molars when cervical headgear is used alone or in combination with rapid maxillary expansion. The sample was composed of 36 subjects (aged 9 to 13 years), treated in the Faculty of Dentistry, Pontifícia Universidade Cat;aaolica, Rio Grande do Sul, Brazil. The individuals were in good health and in their pubertal growth period. All had Class II division 1 malocclusion. The patients were divided into two groups: group 1 (22 subjects), Class II, with a normal transverse maxilla treated with cervical traction headgear (HG) 400 g 12 h/d, and group 2 (14 subjects), Class II maxillary transverse deficiency treated with rapid maxillary expansion plus cervical traction headgear (RME + HG). An additional group 3 (17 subjects) served as a control group and included individuals with the same characteristics. All subjects had two lateral cephalograms: initial (T1) and progress (T2), taken 6 months later. Differences between T1 and T2 were compared with the Student's t-test, and three groups were compared by the analysis of variance and Tukey multiple comparison test. Results showed greater distal tipping and greater distal movement of the first permanent molars in group 1 (HG) than in group 2 (RME + HG), P < .05. No extrusion of first permanent molar occurred in either group (P > .05). The hypothesis was rejected. Cervical traction headgear alone produced greater distal movement effects in maxillary first permanent molars when compared with rapid maxillary expansion associated with cervical headgear.

Studies of an Association in Boys of Blood Pressure and the Y Chromosome

Variations in the Y chromosome have shown significant, albeit inconsistent, associations with hypertension in men. Studies of peripubertal subjects might reveal more information on the origins of the Y chromosome's influence on blood pressure (BP). In the current study, we examined the association of a HindIII restriction site on the Y chromosome with BP in a cohort of young men. Pubertal growth-based analyses were performed in 80 unrelated males with multiple measurements spanning time points beginning before and extending to after their pubertal growth. Blood pressure, height, and weight were measured approximately every 6 months. The period of pubertal growth was used to approximate the time for puberty. The association of the HindIII restriction site to systolic and diastolic BP was determined using a mixed model ANOVA. Estimated systolic and diastolic BPs were higher in HindIII(-) males in the period before, as well as in the period after pubertal growth (systolic BP 2.6 +/- 1.3 mm Hg higher, P < .05), and diastolic BP 2.3 +/- 1.2 mm Hg higher, P = .050). In addition, HindIII(-) males were younger at onset of peak height velocity (12.7 +/- 0.1 v 13.3 +/- 0.1 years, P < .001). In African Americans, an earlier age of maximal height velocity was associated with a higher systolic and diastolic BP (P < .05 and .02, respectively). The results suggest that variations in genes on the Y chromosome may affect BP in peripubertal males, possibly even before onset of puberty.

Chronologic age and skeletal maturation of the cervical vertebrae and hand-wrist: Is there a relationship?

The aims of this study were (1) to investigate the relationship between chronologic age and maturation of cervical vertebrae, (2) to identify the relationship between chronologic age and maturation stage evaluated by hand-wrist radiographs, and (3) to determine whether the maturation of cervical vertebrae correlates with maturation indicated by hand-wrist radiographs in a Turkish population. The samples were derived from lateral cephalometric and hand-wrist radiographs of 503 subjects (213 male, 290 female; ages, 5.3-24.1 years). Cervical vertebral development was evaluated by the method of Hassel and Farman. Skeletal maturation of each hand-wrist radiograph was determined according to the method described by Björk and Grave, and Brown's system. The Spearman rank-order correlation coefficients were estimated separately for males and females to measure the relationships among chronologic age, cervical vertebral maturation, and the skeletal maturation measured at the hand-wrist. The Spearman correlation coefficients were 0.72 (P <.001) between chronologic age and cervical vertebrae skeletal maturation, and 0.79 (P < .001) between chronologic age and maturation via hand-wrist radiographs. The correlation coefficient between hand-wrist and cervical-vertebrae maturation was 0.86 (P <.001). The cervical-vertebrae maturation stages are clinically useful maturity indicators of the pubertal growth period Turkish subjects.

Development of spinal posture in a cohort of children from the age of 11 to 22 years.

Spinal posture and the resultant changes during the entire pubertal growth period have not been reported previously. No cohort study has focused on the development of spinal posture during both the ascending and the descending phase of peak growth of the spine. The growth and development of a population-based cohort of 1060 children was followed up for a period of 11 years. The children were examined 5 times, at the ages of 11, 12, 13, 14 and 22 years. A total of 430 subjects participated in the final examination. Sagittal spinal profiles were determined using spinal pantography by the same physician throughout the study. Thoracic kyphosis was more prominent in males at all examinations. The increasing tendency towards thoracic kyphosis continued in men, but not in women. The degree of lumbar lordosis was constant during puberty and young adulthood. Women were more lordotic at all ages. Thoracic hyperkyphosis of > or =45 degrees was as prevalent in boys as girls at 14 years, but significantly (P<0.0001) more prevalent in men (9.6%) than in women (0.9%) at 22 years. The degree of mean thoracic kyphosis and the prevalence of hyperkyphosis increased in men during the descending phase of peak growth of the spine, but decreased in women.

Cardiac and vascular function in adolescents and young adults with type 1 diabetes.

The objective was to prospectively define cardiac and vascular function in adolescents and young adults with type 1 diabetes over a 3-year period. Thirty-three subjects with type 1 diabetes were studied in 1998, and 28 returned for follow-up in 2001. There were 28 controls without diabetes. All subjects underwent ultrasonography of the carotid artery to determine distensibility, compliance, and intimal-medial thickness, as well as echocardiographic studies, lipid profile, and measurement of hemoglobin A1c (HbA1c) levels and urinary albumin excretion rate. The diabetes group showed no significant change over the 3-year follow-up in lipid profile, HbA1c level, or albumin excretion rate, but a significant increase in body mass index. The diabetes and control groups were similar in age, lipid profile, and albumin excretion rate. Carotid artery distensibility and compliance in the diabetes group increased significantly from baseline to follow-up but did not differ significantly from controls. The intimal-medial thickness of the diabetes group remained unchanged over time but tended to be higher than controls. Echocardiographic studies showed no difference between the diabetes and control groups, but there was a small change in left ventricular posterior diastolic wall diameter in the subjects with diabetes over the 3-year period. There was an overall improvement in carotid function and no change in cardiac measures in subjects with diabetes over the 3 years, such that cardiac and vascular function were similar to those of controls. The reason for the improvement is uncertain, but may relate to the improvement of insulin sensitivity at the end of the pubertal growth period, rather than to changes in metabolic control or lipid profiles.

Predicting mandibular growth potential with cervical vertebral bone age

This study assessed the possibility of using cervical vertebral bone age determined from cephalometric radiographs to predict mandibular growth potential. The subjects were 2 groups of 20 Japanese girls and young women: one group to derive a formula for predicting mandibular growth potential, the other to compare predicted values with actual values. Each group included subjects in the initial stage of the pubertal growth period and the final stage of growth in early adulthood. A formula for predicting mandibular growth potential that included cervical vertebral bone age and the actual growth of the mandible (condylion-gnathion) was determined with regression analysis. Cervical vertebral bone age, bone age on hand-wrist radiographs, and chronological age were inserted into the formula, and actual values and values predicted with these parameters of the formula for mandibular growth potential were compared. The formula found mandibular growth potential (in millimeters) = −2.76 × cervical vertebral bone age + 38.68. The average error between the value predicted by cervical vertebral bone age and the actual value (1.79 mm) was significantly less ( P < .001) than that between the actual value and the value predicted by chronological age (3.48 mm) and approximately the same as that between the actual value and the value predicted by bone age (2.09 mm). The formula derived from this study might be useful for treating orthodontic patients in the growth stage.

Craniofacial growth and skeletal maturation: a mixed longitudinal study.

The purpose of this study was to investigate the relationship between craniofacial growth and skeletal maturation. The material consisted of the cephalometric and hand-wrist film pairs of 35 males and 43 females (78 subjects) whose development was followed for a period of 4 to 7 years. The subjects were grouped according to their skeletal maturation. Their mean ages were: Group I 10.27, Group II 11.55, and Group III 14.79 years, respectively, at the beginning of the observation period. Intra- and inter-group differences were examined through paired t-tests, and Pearson correlation analysis was used to detect the relationship between craniofacial growth and skeletal maturation (percentage growth potential). The results show that the middle cranial base (T-W) maintained its stability in all pubertal growth periods. However, posterior cranial base length (T-Ba) increases significantly (P < 0.001) throughout the same period. There were similar increases in the vertical dimensions of the face and alveolar height throughout pubertal growth. Despite the intensified increases in both the sagittal and vertical directions, facial characteristics were constant in the sagittal direction. The skeletal development (percentage growth potential) has clearly been effective in the vertical facial development commencing in Group I and reaching its maximum level in Group II. However Cd-Go was the exception.

Age of pubertal onset affects the intensity and duration of pubertal growth peak but not final height.

This paper analyzed the intensity and duration of height growth during puberty in boys and girls in relation to rhythm of maturation. A longitudinal clinical follow-up between ages of 10 and 20 years, was carried out in a sample of 251 children grouped according to age at pubertal onset: boys (genital stage 2) at the ages of 11 (n = 28), 12 (n = 38), 13 (n = 42), and 14 (n = 27); and girls (breast stage 2) at the ages of 10 (n = 37), 11 (n = 47), 12 (n = 19), and 13 (n = 13). Height was measured annually. Testicular volume and genital development were assessed in boys, and breast development was assessed in girls. There were significant differences (P < 0.001) in height at the age of pubertal onset among maturity groups. Late maturers were taller than early maturers (r = 0.49, P < 0.001 for girls; r = 0.38, P < 0.001 for boys). However, final heights did not differ according to age of onset in either sex. In boys, later onset of puberty was associated with a smaller pubertal height gain (r = -0.60, P < 0.001) and a shorter period of pubertal growth (r = -0.61, P < 0.001). Equally in girls, earlier onset of puberty was associated with a greater pubertal height gain (r = -0.68, P < 0.001) and a longer period of pubertal growth (r = -0.59, P < 0.001). In conclusion, age of pubertal onset does not affect final height attained in both sexes, since there is an inverse compensatory phenomenon in both sexes between height at pubertal onset and the intensity and duration of pubertal growth.

Age-related changes on bone regeneration in midpalatal suture during maxillary expansion in the rat

The purpose of the present study was to investigate age-related changes in bone regeneration during expansion of a midpalatal suture in rats. When the midpalatal suture was expanded for 7 days in rats of four different ages (6, 15, 24, and 52 weeks), it was found to have significantly widened in all groups by the analysis of a histomorphometric method. The expansion-induced widening of the suture was similar in 6, 15, and 24-week-old rats but was significantly less in 52-week-old rats. When the newly mineralized bone area and the osteoid area along the suture in all groups were quantified, newly mineralized bone area in all expansion groups significantly increased compared with corresponding controls, but expansion-induced newly mineralized bone area decreased in an age-dependent manner. Osteoid area also significantly increased by expansion, but expansion-induced osteoid area unexpectedly increased with age up to the 24-week-old rats. In the expansion-induced total bone area (expansion-induced newly mineralized bone area plus osteoid area), there was no significant difference among 6, 15, and 24-week-old rats, but it was markedly decreased in 52-week-old rats. Alkaline phosphatase activity in the suture strongly increased in all expansion groups, whereas increase in the rate of alkaline phosphatase activity clearly was less in 24 and 52-week-old rats. These results suggested that the difficulty of rapid-palatal expansion in 52-week-old rats and age-related decrease in bone regeneration after expansion of the suture within 24-week-old rats may be caused by decrease in mineralization of the bone matrix. Therefore, midpalatal suture can expand even in the cases exceeding the pubertal growth period, but more time may be necessary for mineralized bone to regenerate in the suture. (Am J Orthod Dentofacial Orthop 1998;114:646-53)

The effect of unilateral partial facial paralysis and muscle ablation on craniofacial growth and development: an experimental study in the rabbit.

The effect of unilateral partial facial nerve ablation and unilateral partial midface muscle ablation on craniofacial growth and development was investigated. New Zealand White rabbits (12 days old) were randomly assigned to three experimental groups: control group, to study normal craniofacial growth and development (n = 15); nerve ablation group, surgically induced unilateral paralysis of the buccal branches of the facial nerve (n = 15); and muscle ablation group, surgical unilateral ablation of the facial muscles innervated by the buccal branches of the facial nerve (n = 12). All animals were operated on at the age of 12 days; follow-up evaluations were performed at the ages of 2 months and 6 months. The age of 2 months represents the endpoint of the prepubertal craniofacial growth and development. At the age of 6 months, the animals are fully grown; therefore, the time period between 2 and 6 months is regarded as the pubertal growth period. Computerized dorsoventral roentgencephalometric (measurement of distances and angles) and computer tomographic (three-dimensional volumetric measurements) investigations were performed at both ages. Additional dry skull measurements were performed to determine more precisely the bone segments involved in the craniofacial growth alterations studied. The obtained results indicated the following. Unilateral partial facial paralysis involving the midface resulted in growth alterations analogous to those seen after unilateral total facial paralysis. The growth alterations were not to be seen as a growth restriction (reduction in bony volume) but as growth misdirections (alterations in shape). Major growth alterations were present in those regions closely related to the facial musculature, namely the nasal, maxillary, and premaxillary regions, resulting in a snout deviation toward the operated side. The growth alterations occurred during prepuberty and remained rather stable during puberty. Morphologic signs of muscle denervation were related to the craniofacial growth disturbances. The growth alterations after unilateral partial facial paralysis were mainly biomechanically induced, as they were analogous to those observed after unilateral midfacial muscle ablation. The fact that after unilateral midfacial muscle ablation at the age of 6 months the severity of the alterations had increased was attributed to the scar formation inherent to the surgical procedure.

Longitudinal evaluation of growth changesin class II division 1 subjects

Longitudinal records from the Ohio State University Growth Study were used to compare the skeletal growth changes between Class II division 1 and Class I female subjects between ages 7 and 14. Tensor analysis was used to determine the yearly growth rate and direction. No significant difference was found in cranial base dimension between the Class I and Class II subjects. In Class II subjects, the maxilla (S-N-A) was found to be normally related to the cranial base. However, mandibular position (S-N-B and S-N-Pog) was found to be significantly more retrusive in Class II when compared with Class I subjects. Mandibular length (Ar-Gn) and corpus length (Go-Gn) were found to be shorter in Class II subjects. The ratio of PFH to AFH was found to be smaller in Class II subjects. This is particularly apparent during the pubertal growth period. The y-axis and mandibular plane angle were more open in Class II subjects which also contributed to the retrusive position of the mandible. Maxillo-mandibular difference (A-N-B) between Class I and II subjects was present at age 7 and persisted through puberty, maintaining a greater angle of convexity (A-N-Pg) in Class II subjects. These results suggest that Class II malocclusion can be detected early. The majority of the Class II cases showed mandibular skeletal retrusion or a combination of horizontal and vertical abnormalities of the mandible rather than maxillary protrusion. These skeletal differences remain through puberty without orthodontic intervention. Individual variations were found within each type of malocclusion

Facial growth of skeletal class IIImalocclusion and the effects, limitations, and long-term dentofacial adaptations to chincap therapy

This article outlines the authors' research findings on the craniofacial growth of untreated skeletal Class III malocclusion, as well as the short-term and long-term effects of chincap orthopedic force for controlling Class III mandibular growth. Skeletal Class III malocclusion is believed to be the result of excessive growth of the mandible with respect to the maxilla and/or cranial base. The results of the authors' longitudinal studies show similar maxillary and mandibular incremental growth change during prepubertal, pubertal, and postpubertal periods when compared with Class I subjects. Therefore, it seems reasonable to assume that the skeletal framework of the Class III malocclusion must have been established before the prepubertal growth period. As for treatment with chincap appliances, the study on short-term and long-term effects indicate that, on average, the skeletal profile is greatly improved during the initial stages of chincap therapy. However, such changes are rarely maintained during pubertal growth period. Treatment with chincap appliances seldom alters the inherited prognathic characteristics of skeletal Class III profiles after completion of growth.

Calcium metabolism in girls: current dietary intakes lead to low rates of calcium absorption and retention during puberty

We evaluated the effects of self-selected diets on calcium absorption and calculated retention in girls during pre-, early, and late puberty. Dietary calcium absorption was measured in 51 girls aged 4.9-16.7 y by using a dual-tracer stable-isotope technique. We found that calcium intake was similar among girls of all ages and all degrees of pubertal development and was below the recommended dietary allowance (1200 mg/d) for 21 of 25 girls aged > or = 11 y. The early pubertal period was associated with a higher percent of dietary calcium absorption (34.4 +/- 11.9%) than was the prepubertal (27.7 +/- 8.2%) or late pubertal periods (25.9 +/- 7.8%). Calculated calcium retention averaged 132 +/- 83 mg/d in prepubertal girls, 161 +/- 88 mg/d in early pubertal girls, and 44 +/- 91 mg/d in late pubertal girls. Peak calcium retention during early puberty was far below that previously reported after higher calcium intakes. We conclude that peak periods for calcium retention for girls are in the pre- and early pubertal periods. The current calcium intake of American girls during the pubertal growth period may not enable maximal mineral retention; therefore, increased calcium intakes should be considered.

19 GROWTH AND FINAL HEIGHT IN PATIENTS WITH TURNER SYNDOROME

Short stature is a central feature in Turner's Syndrome. In the last years several treatment schedules have been proposed in order to improve final height. So complete knowledge of the variants of this Syndrome and the expected final height for a specific country is needed. We analyzed the final heights of 86 patients with Turner Syndrome, 32 with a 45X chromosome constitution (X+SD 138.1+4.92 cm) and 52 with a mosaiciam or a structurally abnormal X (136.8±4.73 cm). Forty five patients were longitudinally follow trough their pubertal growth period. Nine girls received treatment with low doses of ethinyl estradiol, 100 ng/Kg/day (group A), 11 started spontaneeus pubertal development and received no treatment (group B) and 26 patients, treated with standard replacement doses of estrogen(17 patients non XD group C and 8 XO group D). In all patients height prediction was calculated by Eayley-Pinnaau method at the onset of spontaneous puberty cr at the beginning of the replacement therapy and the total height gain between this onset and final height was calculated. In prepubertal girls with Turner Syndrome a slight acceleration of growth velocity under treatment with low doses or a conventional estrogen therapy was seen, but final height was the same in all group. We also noticed that Argentine girls with Turner Syndrome have an ultimate height below the average height reported for European (X 143 cm) or American girls (X 142.6 cm).

Ergebnisse Jenaer anthropologischer Schulkinderuntersuchungen zwischen 1880 und 1985

The present report is based on the results from anthropological examinations on schoolchildren, which have been carried out in Jena since 1880. The introduction to the paper gives a survey on the goals of these inquiries, followed by remarks on secular changes in selected measurements of the body (body height, body weight, chest circumference). Besides the extent of the changes in these features, the anticipation of the pubertal growth period and--by means of the relation of body height to chest circumference--a becoming slimmer of today's population of schoolchildren is documented. The comparison of the findings of 1975 and 1985 shows that, regarding the features mentioned, the acceleration in the Jena probands (although in part with reduced intensity) has lasted up to the present time.

Pubertal Growth in Chronic Renal Failure

We evaluated the growth records of 15 boys and 14 girls who developed end-stage renal failure before or during puberty and who were regularly followed from the onset to the end of their pubertal growth spurt. Height data were smoothed by using the kernel estimation method. Mean values for age, height, and height velocity at defined points of the pubertal growth period were compared with those of normal children entering puberty both at an average and late age. The start of the pubertal growth spurt was delayed by 2.5 y in both sexes. Its duration and intensity were significantly reduced. Mean pubertal height gain was 17.3 cm in boys and 13.9 cm in girls, i.e. 58 and 48% of that observed in the late maturing control group. Mean height at the onset of the pubertal spurt in the patients was the same as that in the late maturing healthy girls and 1.0 SD below that of corresponding boys. During the pubertal growth spurt, mean height declined to -2.9 SD in boys and -2.3 SD in girls. Although skeletal maturation was increasingly retarded, we did not observe accelerated growth velocity during late puberty. Our data indicate that most patients reaching end-stage renal failure before or during puberty irreversibly lose growth potential during this period. Renal transplantation did not consistently improve pubertal growth.

GROWTH OF MALES WITH IDIOPATHIC HYPOPITUITARISM WITHOUT GROWTH HORMONE TREATMENT

We report auxologic data on 23 males with idiopathic hypopituitarism who grew up at a time when human growth hormone (GH) was not yet available, while receiving other appropriate hormonal substitution. We had reported previously that their adult heights were not significantly less than those of similar patients who had received GH. In the absence of GH the pubertal growth period was remarkably protracted, averaging 8.7 years for 19 patients during androgen substitution. Pubertal increment in height averaged 20.4 cm during induced puberty, a figure which compares favourably with those reported for GH-treated patients. This implies that GH does not increase the height gained during pubertal growth; the increase in the rate of growth appears to be off-set by a rise in the rate of skeletal maturation. During pubertal growth acceleration of growth of the skeleton seems unavoidably associated with acceleration of its maturation. Adult heights were significantly correlated with the heights at the time of onset of pubertal growth. This is evidence in favour of attempts to stimulate prepubertal growth much more than hitherto by earlier, higher, and more frequent doses of GH. It remains to be proved, however, that before puberty the processes of growth and maturation of the skeleton can be dissociated.

Preventing adolescent pregnancy: meeting the comprehensive range of needs.

Too often, the problem of the pregnant adolescent is approached as if it existed in isolation, disconnected from the remainder of the adolescent's biological and psychosocial environment. Such an approach fails to recognize the interconnectedness of all issues within the adolescent's world, therefore, impeding a successful therapeutic response. In order to administer complete and comprehensive treatment of the problem of teenage pregnancy, the total needs of the pregnant adolescent, the potentially pregnant adolescent and the adolescent male must be addressed. These needs vary with the different stages of adolescent development. During this time in which children learn how to become adults by observing their world and taking cues from the environment, the varying needs are: Early Adolescence--to develop the ability to perceive the long range consequences of their current actions and decisions; to define the boundaries of their independence while relying on major authority figures; and to make important decisions and develop the operational connection between the sex act and birth control. Mid Adolescence--to achieve emancipation from the family and all other authority; to identify with a chosen peer group; to develop an identified sexual identity; and to apply an appreciation for the connection between the sex act and pregnancy to themselves. Late adolescence--to plan for the future and to establish some kind of family. This psychological and social maturational process occurs immediately before, during and after the pubertal growth period. In the United States today, it usually occupies the years between 12 and 21 years.

An evaluation of the method of structural growth prediction.

The method of structural growth prediction introduced by Bjork (1963) was investigated using two sets of lateral cephaiograms of 42 children, taken before and after the pubertal growth period with a four year interval. Growth direction was evaluated on the first cephalogram by eleven different observers, using Bjork's anatomical characteristics. The intra- and interobserver reliability for scoring the different structures was acceptable. There was no absolute correlation between the scores for the different criteria and mandibular growth rotation during the four years of observation. This does not mean that the method is useless but, in cases showing relatively small rotational changes, as in this material, the method does not work well. Further study of the structural characteristics is needed in cases showing extreme anterior or posterior growth rotation.