Insulin-like growth factor I: A biologic maturation indicator

Evaluation of an objective staging system for assessment of cervical vertebral maturation

BACKGROUND

The aim of this study was to evaluate an objective method for Cervical Vertebral Maturation (CVM) staging.

METHODS

An initial sample of 647 Lateral Cephalometric Radiographs (LCR) were staged according to the CVM (Baccetti et al.) by 4 examiners. The final sample (n = 394) included LCR on which the staging of the 4 investigators matched. The objective staging was performed by a single operator. The sample was divided according to the maturational stages into pre-pubertal, pubertal and post-pubertal groups. Measurements were performed on the cervical vertebrae (C2, C3 and C4). The angle between posterior and superior borders for C3 and C4 was the Superior Wall Inclination Angle (SWIA). Concavity Depth (CD) for C2, C3 and C4, and Body Shape (BS) (ratio of width to height of C3 and C4). Measurements of the 3 groups were compared.

RESULTS

Reliability of subjective staging was high (intra-observer reliability, 0.948; inter-observer reliability, 0.967). Good agreement was observed for the outcomes measured. Intra-observer reliability was good (0.918, 0.885 and 0.722 for CD, BS and SWIA, respectively). The same was for the inter-observer reliability results (0.902, 0.889 and 0.728 for CD, BS and SWIA, respectively). Significant differences were observed for mean values of SWIA and BS and median values of CD within maturational stage. Similar findings were observed when the outcomes were compared at different phases (P < 0.001).

CONCLUSIONS

A standardized, objective staging system using linear, angular measurements and ratios was applied for the determination of cervical vertebral maturation.

Reliability of salivary biomarkers as skeletal maturity indicators: A systematic review

OBJECTIVE

To assess the reliability of different salivary biomarkers as skeletal maturity indicators when compared with other methods of skeletal maturity assessment.

METHODS

A comprehensive search was conducted on three electronic databases: PUBMED, Google scholar and Cochrane library for the articles published from 2000 to July 2021. Assessment of skeletal age on the basis of levels of different salivary biomarkers at different pubertal stages was considered as the primary outcome. Electronic search, data collection and risk of bias assessment were performed by two authors with conflict resolution by the third author.

RESULTS

Total 158 articles were retrieved after screening of titles, abstracts and full texts of all articles, of which 15 articles were selected for qualitative synthesis. All these studies were cross-sectional in design. These studies compared the levels of different salivary biomarkers as Alkaline Phosphatase (ALP), Insulin-like Growth Factor - I (IGF-I), Insulin-like Growth Factor Binding Protein-3 (IGFBP-3), Cortisol, Indian Hedgehog (IHH) protein and Dehydroepiandrosterone sulphate (DHEAS) with other methods of skeletal age estimation. Out of these six biomarkers salivary IGF-1 is a reliable indicator for skeletal maturity assessment.

CONCLUSION

The current evidence suggests that salivary biomarkers can be used as an adjunct for growth prediction during orthodontic treatment planning along with other methods of skeletal maturation assessment. Still there is need for further research with longitudinal studies in this field.

Serum biomarkers associated with radiographic skeletal maturity indicators: A systematic review and meta-analysis

Objective:

To evaluate the relevant scientific literature to determine the association between different serum biomarker levels and radiographic skeletal maturity indicators.

Data Search, Screening and Eligibility:

A literature search was carried out on PubMed, Cochrane Library, Google Scholar, Semantic Scholar, Science Direct and Opengrey.eu up to November 2021 and 7466 records were retrieved via the electronic search. Study selection, data extraction and subsequent risk of bias assessment (RoB) was carried out independently by two authors. In case of any discrepancy, a third author was consulted.

Results:

After the exclusion of duplicates and the application of inclusion exclusion criteria, 19 studies (published in 25 articles) were included in the systematic review out of which 17 had a cross-sectional and two had a cohort study design. For the meta-analysis, based on the homogeneity, five cross-sectional studies measuring serum IGF-1 levels were incorporated. The meta-analysis revealed that the serum IGF-1 levels peak at the CS4 stage (401.77 ng/mL [333.50 – 470.05]) in the pooled group. However, in the subgroup analysis, it was found that the serum IGF-1 levels peak at CS3 in women (422.82 ng/mL [377.46–468.18]) and CS4 in men (487.04 ng/mL [391.83–582.25]).

Conclusion:

Among the various biomarkers evaluated, serum IGF-1 was the most associated with different stages of radiographic skeletal maturity indicators with its levels peaking at CS3 in women and CS4 in men.

Association of Salivary IGF and IGF/IGFBP-3 Molar Ratio with Cervical Vertebral Maturation Stages from Pre-Adolescent to Post-Adolescent Transition Period-A Cross-Sectional Exploratory Study

Background: The relevance of growth determination in orthodontics is driving the search for the most precise and least invasive way of tracking the pubertal growth spurt. Objectives: The aim was to explore whether minimally invasive salivary estimation of biomarkers Insulin-like growth factor (IGF-1) and Insulin-like growth factor binding protein-3 (IGFBP-3) could be used to estimate skeletal maturity with diagnostic accuracy, especially in children and adolescent age groups. Subjects and methods: The cross-sectional study was conducted on 105 participants aged 6−25 years from the out-patient Department of Preventive Dental Science at Majmaah University between the period 2 January 2021 and 12 July 2021. Each subject’s lateral cephalogram radiograph was categorized based on skeletal maturity, and saliva samples were estimated for IGF-1 and IGFBP-3 using the respective ELISA kits. Two-way ANOVA with interaction was applied to examine the main effects due to cervical vertebral maturation staging (CVS), Sex and interaction effect due to CVS, and Sex on study parameters. Karl Pearson’s Product Moment Correlation Coefficient was calculated for finding a significant association between IGF, IGFBP3, and the IGF-1/IGFBP3 molar ratio. Results: Highest mean salivary IGF-1 was observed in the pubertal peak stage, which coincides with cervical vertebral maturity stages 3 and 4 (CVS3 and CVS4) for both males (2.57 ng/mL) and females (1.57 ng/mL) and the lowest mean level of IGF-1 for females (0.85 ng/mL) and males (1.22 ng/mL) was observed during the prepubertal stage. There exists a significant variation in IGF-1 between males and females in the pubertal stage (p < 0.01), but the difference is very narrow in the prepubertal and post-pubertal groups (p > 0.05). There was no significant interaction effect of different skeletal stages and gender on the IGFBP3 and the IGF-1/IGFBP3 molar ratio (p > 0.05), but there exists a significant interaction effect on IGF-1 (p < 0.05). Conclusion: Estimation of the IGF-1 and the IGF-1/IGFBP3 molar ratio in saliva, being a non-invasive biological marker, could serve as an adjunctive tool along with radiographic assessment in estimating growth maturity in the adolescence age group. By initiating orthodontic treatment during the mandibular growth peak in adolescence, a positive outcome is ensured in managing skeletal deformities within the craniofacial complex.

Correlation between Salivary Levels of IGF-1, IGFBP-3, IGF-1/IGFBP3 Ratio with Skeletal Maturity Using Hand-Wrist Radiographs

Objective: The relevance of growth determination in orthodontics is driving the search for the most precise and least invasive way of tracking the pubertal growth spurt. Our aim was to explore whether minimally invasive salivary estimation of biomarkers Insulin-like growth factor (IGF-1) and Insulin-like growth factor binding protein-3 (IGFBP-3) could be used to estimate skeletal maturity for clinical convenience, especially in children and adolescent age groups. Materials and Method: The cross-sectional study was conducted on 90 participants (56 girls and 34 males) with ages ranging from 6 to 25 years. Each subject’s hand-wrist radiograph was categorized based on skeletal maturity, and saliva samples were estimated for IGF-1 and IGFBP-3 using the respective ELISA kits. Kruskal−Wallis nonparametric ANOVA was applied to compare different skeletal stages. Results: The study demonstrated low salivary IGF-1 levels at the prepubertal stage, with increase during pubertal onset and peak pubertal stage followed by a decline during pubertal deceleration to growth completion. Spearman’s correlation coefficient demonstrated a strong positive association (r = 0.98 p < 0.01) between salivary IGF/IGFBP-3 ratio and different stages of skeletal maturity. Conclusion: Salivary IGF-1, IGFBP-3, and IGF/IGFBP-3 ratio could serve as a potential biochemical marker for predicting the completion of skeletal maturity.

Salivary IGF-1 and Alkaline Phosphatase-Based Modeling for Skeletal Maturity Prediction in Orthodontic Patients

Results

A strong positive correlation was found between CA and cervical stages (r = 0.836, P < 0.001). Based on the regression model analysis, the model which combined IGF-1, ALP, and CA provided the best prediction at P < 0.001 with McFadden's pseudo R² value of 0.552 for cervical stage prediction and 0.646 for growth phase prediction. In particular, its predictive ability for the prepubertal, pubertal, and postpubertal growth phases was 95%, 80%, and 90%, respectively.

Conclusions

A new model with the combination of salivary IGF-1 and ALP with CA can be used as a less invasive method to determine the cervical stage and also growth phase with high predictive ability in healthy subjects.

Can IGF-1 serve as a reliable skeletal maturity indicator? A meta-analysis

BACKGROUND

Many clinical studies have evaluated the role of biochemical mediators like insulin-like growth factor 1 (IGF-1) in assessment of skeletal maturity. But still the reliability of IGF‑1 as an indicator of skeletal maturity remains controversial.

OBJECTIVE

To assess the correlation between IGF‑1 and different radiographic skeletal maturity indicators.

SEARCH METHODS

Seven electronic databases (PubMed, Scopus, EMBASE, Medline, Cochrane CENTRAL, Web of Science and SciELO) were searched until January 2020 without any restriction based on language or date of publication.

SELECTION CRITERIA

The study design included cross-sectional and longitudinal studies comparing IGF‑1 and other skeletal maturity indicators (SMIs).

DATA COLLECTION AND ANALYSIS

Data extraction was done by two reviewers independently; 15 studies were eligible to be included in the quantitative synthesis.

RESULTS

There was significant positive correlation between IGF‑1 and different SMIs until puberty which was 0.95 (confidence interval [CI] = 0.89, 1.02) for males and 0.87 (CI = 0.77, 0.97) for females. A negative correlation between IGF‑1 and different SMIs was found after puberty which was -0.86 (CI = -0.97, -0.75) for males and -0.89 (CI = -0.98, -0.81) for females. The type of SMI compared and type of IGF‑1 sample used accounted for the high heterogeneity found across the studies. Chronological age and number of months passed after puberty showed moderate negative correlation with mean IGF‑1 levels which were -0.57 (CI = -0.67, -0.47) and -0.54 (CI = -0.66, -0.42). Annual increments in mandibular length showed significant positive correlation of 0.69 (CI = 0.48, 0.90).

CONCLUSIONS

IGF‑1 would serve as a promising alternative to conventional radiographic skeletal maturity indicators and in predicting the amount of residual mandibular growth.

Non-invasive methods for the assessment of biomarkers and their correlation with radiographic maturity indicators - a scoping review

BACKGROUND

Detection of skeletal maturity is vital in orthodontic treatment timing and planning. Traditional methods include hand-wrist radiography and cervical vertebral maturation index (CVMI). Though the radiographic methods are well established and routinely used to assess skeletal maturation, they carry the drawback of subjective perception and low reproducibility. With evolving concepts, skeletal maturation has been assessed quantitatively through biomarkers obtained from saliva, gingival crevicular fluid (GCF), and urine. The scoping review aims to explore the various biomarkers assessed through non-invasive methods and their correlation with radiographic skeletal maturity.

METHODOLOGY

The literature search was carried out on MEDLINE via Pubmed, Cochrane Library (Cochrane database of systematic reviews), Cochrane central register of controlled trials (CENTRAL), Google Scholar, Semantic Scholar, ScienceDirect, and Opengrey.eu for articles up to and including November 2020. Pertinent articles were selected based on inclusion and exclusion criteria. The results were tabulated based on the type of sample collected, the biomarker assessed, method of sample collection, and the radiographic method used.

RESULTS

The literature search resulted in 12 relevant articles. Among all the studies, 10 studies showed that the concentration of biomarkers increases during the pubertal growth peak. On the contrary, 2 articles showed no significant difference between the levels of biomarkers and pubertal growth peak.

CONCLUSION

It can be concluded that the level of biomarkers increases during the pubertal growth spurt and can provide a quantitative way of assessing skeletal maturity.

Comparison of the difference in serum insulin growth factor-1 levels between chronological age and bone age among children

OBJECTIVE

By measuring serum insulin-like growth factor-1 (IGF-1) levels in children aged 2-16, we aimed to analyze the changes in IGF-1 levels in different sex and age groups, and compare the consistency of IGF-1 results evaluated by chronological age (CA) and bone age (BA) in children.

METHODS

A cross-sectional study was conducted between January 2017 and December 2020 among 2979 relatively healthy children who attended the Department of Growth and Development outpatient clinic and health care center of the Affiliated Children's Hospital of the Capital Institute of Pediatrics and underwent health examination and development assessment. Height, weight, and Tanner pubertal stage were measured by pediatricians. The CHN method was used to estimate BA. Venous blood samples were collected from the children, and IGF-1 levels were determined via chemiluminescence.

RESULTS

IGF-1 levels in childhood increased slowly with age, dramatically during puberty,and continuously withgrowth until to 15 years for boys and reached a peak value at 13 years for girls based on CA. IGF-1 levels reached peak values at 14 and 13 years for boys and girls, respectively, based on BA. There were differences in IGF-1 values between the CA and BA groups at the age of 10-11 years for boys and 7-11 years for girls. A total of 103 boys (7.7%) and 17 girls (1.0%) had IGF-1 levels below the lower limit of the reference range based on CA; evaluating based on BA, there were 82 boys (6.1%) and 15 girls (0.9%) still had IGF-1 values less than the lower limit of the reference range. Eighteen boys (1.3%) and 173 girls (10.5%) had IGF-1 levels above the upper limit of the reference range based on CA; evaluating based on BA, these numbers reduced to 5 (0.4%) among boys and 41 (2.5%) among girls.

CONCLUSIONS

There is a significant difference between BA and CA in evaluating IGF-1 levels in children, which can significantly reduce the proportion of IGF-1 values above the upper limit of the kit reference range in children. This suggests that children with BA advanced in pubertal period, the evaluating results of IGF-1 should be corrected by using BA.

Preliminary validation of serotransferrin and vitamin D binding protein in the gingival crevicular fluid as candidate biomarkers for pubertal growth peak in subjects with Class I and Class II malocclusion

INTRODUCTION

Identification of pubertal growth peak is of great importance for the orthopedic treatment of Class II malocclusion. Our previous work demonstrated that vitamin D binding protein (DBP) and serotransferrin (TF) in gingival crevicular fluid (GCF) could be candidate biomarkers of pubertal growth peak. This research aimed to preliminarily validate TF and DBP in subjects with Class I and Class II malocclusion, to compare their diagnostic accuracy, and to construct a statistic model to help the diagnosis of skeletal pubertal peak.

METHODS

Sixty-six circumpubertal subjects were recruited, including 32 subjects with Class I malocclusion and 34 subjects with Class II malocclusion. All subjects were divided into prepubertal, pubertal, and postpubertal groups according to their cervical vertebral maturation stages. GCF samples were collected, and the concentration of DBP and TF were detected by enzyme-linked immunosorbent assay.

RESULTS

Percentage of TF in GCF was significantly higher in pubertal than in prepubertal and postpubertal groups, in subjects with Class I and Class II malocclusion, whereas the difference observed in DBP was less significant. The diagnostic accuracy of TF was better than DBP and chronological age. The most optimal thresholds of maxillary and mandibular TF in distinguishing pubertal from nonpubertal subjects were 4.20% and 4.09%, respectively. The combination of TF and age exhibited the best diagnostic accuracy.

CONCLUSIONS

TF in GCF could be considered as a potential biomarker of pubertal peak and can assist the diagnosis of skeletal pubertal peak.

Serum DHEA-S levels could be used as a comparable diagnostic test to assess the pubertal growth spurt in dentofacial orthopedics

Background

Pubertal growth spurt assessment guides the timing of intervention for correcting the skeletal discrepancies in dentofacial orthopedics. Serum hormones are being studied for the skeletal age assessment to avoid unnecessary radiographic exposure. The present study is to evaluate the relationship of serum hormones dehydroepiandrosterone-sulfate (DHEA-S), insulin-like growth factor (IGF-1), and cervical vertebral stages (CS stages) in the skeletal age assessment of orthodontics patients around the circumpubertal age.

Methods

A total of ninety subjects with age ranging from 7 to 21 years were selected and divided into two groups based on the sex (45 males, 45 females). They were further distributed in each group based on the six CS stages determined from the lateral cephalogram. Blood samples from each subject were collected to evaluate the serum DHEA-S and IGF-1 levels by using the enzyme-linked immunosorbent assay (ELISA). Collected data were analyzed in SPSS software with a test of normalcy, unpaired t test, and one-way analysis of variance (ANOVA) followed by the least significant difference (LSD) post hoc comparison test and univariate regression analysis.

Results

The highest mean serum hormone levels were found in CS 4 in group A (male) and CS 3 in group B (female). ANOVA results showed that there was a significant difference in the serum hormone levels among the different CS stages in both the groups for both the hormones. Statistically, a significant difference was found between each CS stages for both the hormones except in the DHEA-S levels between CS 5 and CS 6.

Conclusions

The mean serum DHEA-S levels followed a typical pattern from the CS 1 till CS 6 which was comparable and similar to the mean serum IGF-1 levels in respect to CS stages. Thus, serum DHEA-S levels could be used as a possible diagnostic test for the assessment of the skeletal pubertal growth spurt in dentofacial orthopedics.

Longitudinal evaluation of the association between Insulin-like growth factor-1, Bone specific alkaline phosphatase and changes in mandibular length

The aim of the current longitudinal study was to assess the levels of serum Bone-specific alkaline phosphatase (BALP) and serum Insulin like growth factor-1 (IGF-1) in different cervical vertebral maturation index (CVMI) stages and observe their association with the mandibular growth. Blood samples and lateral cephalograms of 63 subjects (age group of 11–17 years) were obtained at two time points, 12 months apart. On the basis of CVMI, all subjects were divided into six groups based on whether the subjects remained in same CVMI stage or transitioned to the next CVMI stage. Annual mandibular length was related with serum BALP and serum IGF-1 levels estimated using ELISA. Serum IGF-1 and BALP attained highest levels at CVMI stage 3 with peak BALP levels observed earlier than IGF-1. Although a positive correlation was determined between IGF-1 and BALP but BALP followed skeletal growth pattern more precisely. Overall IGF-1 and BALP were negatively correlated with mandibular length with notable growth in CVMI groups 3–3 (P < 0.01), 3-4 (P < 0.01), 4-4 (P < 0.001) and 5-5 (P < 0.001). In conclusion, BALP is a potential biomarker for skeletal growth assessment. However, the mandibular growth pattern was independent of changes in IGF-1 and BALP.

Hsa-let-7c controls the committed differentiation of IGF-1-treated mesenchymal stem cells derived from dental pulps by targeting IGF-1R via the MAPK pathways

The putative tumor suppressor microRNA let-7c is extensively associated with the biological properties of cancer cells. However, the potential involvement of let-7c in the differentiation of mesenchymal stem cells has not been fully explored. In this study, we investigated the influence of hsa-let-7c (let-7c) on the proliferation and differentiation of human dental pulp-derived mesenchymal stem cells (DPMSCs) treated with insulin-like growth factor 1 (IGF-1) via flow cytometry, CCK-8 assays, alizarin red staining, real-time RT-PCR, and western blotting. In general, the proliferative capabilities and cell viability of DPMSCs were not significantly affected by the overexpression or deletion of let-7c. However, overexpression of let-7c significantly inhibited the expression of IGF-1 receptor (IGF-1R) and downregulated the osteo/odontogenic differentiation of DPMSCs, as indicated by decreased levels of several osteo/odontogenic markers (osteocalcin, osterix, runt-related transcription factor 2, dentin sialophosphoprotein, dentin sialoprotein, alkaline phosphatase, type 1 collagen, and dentin matrix protein 1) in IGF-1-treated DPMSCs. Inversely, deletion of let-7c resulted in increased IGF-1R levels and enhanced osteo/odontogenic differentiation. Furthermore, the ERK, JNK, and P38 MAPK pathways were significantly inhibited following the overexpression of let-7c in DPMSCs. Deletion of let-7c promoted the activation of the JNK and P38 MAPK pathways. Our cumulative findings indicate that Let-7c can inhibit the osteo/odontogenic differentiation of IGF-1-treated DPMSCs by targeting IGF-1R via the JNK/P38 MAPK signaling pathways.

Bone-specific alkaline phosphatase - a potential biomarker for skeletal growth assessment

OBJECTIVE

The present study was aimed to assess levels of serum Bone-specific alkaline phosphatase (BALP) and serum Insulin-like growth factor-1 (IGF-1) and comparing with cervical vertebral maturation index (CVMI) stages.

DESIGN

Cross-sectional study.

SETTING

Maulana Azad Institute of Dental Sciences, New Delhi, India.

PARTICIPANTS

150 subjects (75 males and 75 females) in the age group of 8-20 years.

METHODS

Subjects were divided into six CVMI stages. Enzyme-linked immunosorbant assay was performed for the estimation of serum BALP and serum IGF-1 levels. Mann-Whitney U test was performed to compare mean ranks of serum BALP and serum IGF-1 with different CVMI stages. Spearman correlation between serum BALP and serum IGF-1 was done across 6 CVMI stages.

RESULTS

Peak serum IGF-1 levels were found at CVMI stages 4 and 3 for males and females respectively. Peak levels for serum BALP were found at stage 3 for both genders with significant differences from other stages. A statistically significant correlation was seen between serum IGF-1 and serum BALP from CVMI stages 1 to 3 and 4 to 6 (p < .01).

CONCLUSIONS

BALP showed promising results and can be employed as a potential biomarker for the estimation of growth status.

Serum IGF-1, IGFBP-3 and their ratio: Potential biochemical growth maturity indicators

BACKGROUND

Determination of skeletal maturation and remaining growth potential is an essential part of treatment planning in orthodontics. The aim of our study was to determine the relationship between IGF-1 levels, IGFBP-3 levels with CVM staging to track the pre pubertal and pubertal growth spurts in female patients in North Indian population.

METHODS

This cross-sectional study was conducted on ninety female subjects in the age group of 8-20 years. Blood samples were collected and centrifuged and serum samples were then analysed by Human IGF-1 and IGFBP-3 enzyme-linked immunosorbent assay kits, specific for IGF-1 and IGFBP-3, respectively. CVM staging on lateral cephalometric radiograph was determined for all patients. Analysis of variance test followed by a post hoc test was used to compare mean IGF-1 and IGFBP-3 corresponding to six stages of cervical vertebrae maturation stages. Linear Pearson's correlations were performed to determine the trends of IGF-1, IGFBP-3, and its ratio relating to CVM stage. The kappa statistic was used to measure inter and intra examiner reliability. P value <0.05 was considered as statistically significant.

RESULTS

Mean serum IGF-1 levels were found to be highest (403.3 ± 12.3 ng/ml) at CVMI3 stage of CVMI. The post-hoc test revealed a significant difference in IGF-1 levels between all stages of CVMI, thereby indicating a specific range of IGF-1 levels for a specific skeletal stage. Mean serum IGFBP-3 levels were found to be highest (5186.8 ± 1384.2 ng/ml) at CVMI4 stage of CVMI. The mean serum IGFBP-3 levels at CVMI4 were found to be significantly higher than the levels at all other CVMI stages except CVMI3 stage.

CONCLUSIONS

IGF-1 and IGFBP-3 can serve as a potential biochemical indicator for assessment of skeletal maturity.

Osteocalcin and serum insulin-like growth factor-1 as biochemical skeletal maturity indicators

Background

With change in concepts of growth determination methods, there is a surge in the measurement of biomarkers for appraisal of growth status. Osteocalcin is a bone-specific protein and was observed to parallel the normal growth curve. Hence, the present study was intended to assess the levels of serum osteocalcin and serum insulin-like growth factor-1 (IGF-1) and compare them with cervical vertebral maturation index (CVMI) stages.

Methods

The cross-sectional study was performed on 150 subjects (75 males and 75 females) in the age group of 8–20 years and segregated into six CVMI stages. Serum osteocalcin and IGF-1 were estimated by ELISA. Mann-Whitney U test was used to compare the mean ranks of serum osteocalcin and serum IGF-1 with different CVMI stages. Spearman correlation was performed to find association between serum osteocalcin and serum IGF-1 across six CVMI stages.

Results

Peak serum IGF-1 levels were obtained at CVMI stages 4 and 3 for males and females, respectively, with insignificant difference between stages 3 and 4 in females. Peak serum osteocalcin levels were found at stage 5 and 3 for males and females with insignificant difference from other stages except stages 5 and 6 in males. A statistically significant correlation was seen between serum IGF-1 and serum osteocalcin across six CVMI stages (P < 0.01).

Conclusions

Osteocalcin followed IGF-1 across all CVMI stages but showed insignificant interstage differences.

Serum and urine insulin-like growth factor-1 as biochemical growth maturity indicators

INTRODUCTION

Biochemical markers are agents directly involved in bone growth and remodeling and can be quantitatively evaluated from various biologic fluids. The aim of this study was to assess the changes in the levels of insulin-like growth factor-1 (IGF-1) in serum and urine as a growth maturity indicator and to compare them with the cervical vertebral maturation radiographic stages.

METHODS

The study was conducted with 72 female subjects aged 8 to 20 years. Cervical vertebral maturation stages, and serum and urine IGF-1 levels were recorded for all subjects, and the subjects were equally divided into the 6 cervical vertebral maturation groups. Median values of IGF-1 for each stage of cervical vertebral maturation were calculated and statistically compared with those of the other stages.

RESULTS

The levels of serum and urine IGF-1 at stage 4 of cervical vertebral maturation were significantly higher than those from the other stages (P <0.01). Stage 4 corresponded to a mean age of 13.67 years. A significant correlation was observed between serum and urine IGF-1 (P <0.001).

CONCLUSIONS

Urine IGF-1 follows the growth curve similar to serum IGF-1. Thus, urine IGF-1 may be regarded as a promising noninvasive tool for growth assessment. Further research is necessary to validate these results in a different population and with a larger sample.

Reliability of Growth Indicators and Efficiency of Functional Treatment for Skeletal Class II Malocclusion: Current Evidence and Controversies

Current evidence on the reliability of growth indicators in the identification of the pubertal growth spurt and efficiency of functional treatment for skeletal Class II malocclusion, the timing of which relies on such indicators, is highly controversial. Regarding growth indicators, the hand and wrist (including the sole middle phalanx of the third finger) maturation method and the standing height recording appear to be most reliable. Other methods are subjected to controversies or were showed to be unreliable. Main sources of controversies include use of single stages instead of ossification events and diagnostic reliability conjecturally based on correlation analyses. Regarding evidence on the efficiency of functional treatment, when treated during the pubertal growth spurt, more favorable response is seen in skeletal Class II patients even though large individual responsiveness remains. Main sources of controversies include design of clinical trials, definition of Class II malocclusion, and lack of inclusion of skeletal maturity among the prognostic factors. While no growth indicator may be considered to have a full diagnostic reliability in the identification of the pubertal growth spurt, their use may still be recommended for increasing efficiency of functional treatment for skeletal Class II malocclusion.

Serum insulin-like growth factor-1 levels in females and males in different cervical vertebral maturation stages

OBJECTIVE

The aim of this cross sectional study was to assess serum insulin-like growth factor-1 (IGF-1) levels in female and male subjects at various cervical vertebral maturation (CVM) stages.

MATERIAL AND METHODS

The study sample consisted of 60 subjects, 30 females and 30 males, in the age range of 8-23 years. For all subjects, serum IGF-1 level was estimated from blood samples by means of chemiluminescence immunoassay (CLIA). CVM was assessed on lateral cephalograms using the method described by Baccetti. Serum IGF-1 level and cervical staging data of 30 female subjects were included and taken from records of a previous study. Data were analyzed by Kruska-Wallis and Mann Whitney test. Bonferroni correction was carried out and alpha value was set at 0.003.

RESULTS

Peak value of serum IGF-1 was observed in cervical stages CS3 in females and CS4 in males. Differences between males and females were observed in mean values of IGF-1 at stages CS3, 4 and 5. The highest mean IGF-1 levels in males was observed in CS4 followed by CS5 and third highest in CS3; whereas in females the highest mean IGF-1 levelswas observed in CS3 followed by CS4 and third highest in CS5. Trends of IGF-1 in relation to the cervical stages also differed between males and females. The greatest mean serum IGF-1 value for both sexes was comparable, for females (397 ng/ml) values were slightly higher than in males (394.8 ng/ml).

CONCLUSIONS

Males and females showed differences in IGF-1 trends and levels at different cervical stages.

Longitudinal relationship between insulin-like growth factor-1 levels and vertical facial growth

BACKGROUND

Facial growth in the vertical dimension is the last to be completed and can often be detrimental to the success of dental implants, orthodontic treatment, and orthognathic surgery that young individuals undergo.

AIM

The purpose of this study was to evaluate the longitudinal relationship between changes in total anterior facial height and insulin-like growth factor-1 (IGF-1) levels measured using blood-spot samples.

METHODS

Our sample included 25 orthodontic patients from whom we had access to annual lateral cephalometric radiographs and IGF-1 measurements. Each subject was observed between 2 and 6 times, resulting in 43 annual intervals from a total of 77 observations.

RESULTS

We noted a significant moderate positive correlation (+ 0.48) between the percentage of change in blood-spot IGF-1 levels and the percentage of change in total anterior face height (p = 0.01).

CONCLUSION

Longitudinal changes in IGF-1 levels can be used to predict a patient's vertical facial growth. There was no significant correlation between changes in vertical facial development and a single cross-sectional IGF-1 measurement.

Predicting changes in mandibular length and total anterior facial height using IGF-1, cervical stage, skeletal classification, and gender

Background

The purpose of this study was to predict the annual growth rate of the mandible and total anterior facial height using IGF-1 levels together with cervical stage, skeletal classification, and gender.

Methods

Twenty-five orthodontic patients (12 females and 13 males) had their cervical stages, blood-spot IGF-1 levels, and cephalometric parameters measured at 1-year intervals. The number of years each patient was followed up varied between 1 and 5 years resulting in 43 12-month intervals collected from 77 observations. Descriptive, bivariate, and regression analyses were used to analyze this data.

Results

The linear regression model for predicting the annual mandibular growth rate was significant at p < 0.01 with an R-square value of 0.52. We found that the average IGF-1 level for the interval, the change in IGF-1 level, and the presence of a skeletal class III pattern were statistically significant predictors of mandibular growth. The regression model for predicting the annual change in anterior facial height was significant at p < 0.01 with an R-square value of 0.42. We found that the change in IGF-1 level was the only statistically significant predictor of this outcome.

Conclusions

The proposed method which combines IGF-1 levels with information that is readily available to clinicians can be used to predict the timing and intensity of the growth spurt. These factors together explain more of the observed individual variation in growth rate than any of the factors used in isolation.

Serum IGF-1 levels as a clinical tool for optimizing orthodontic treatment timing

Background

The study aims to associate serum insulin-like growth factor-1 (IGF-1) levels with cervical maturation stages (CS) 3, 4, and 5 on lateral cephalogram in male subjects and to find out peak serum IGF-1 levels among these three stages.

Methods

The study was conducted on 45 male subjects who were at skeletal maturation stage CS-3, CS-4, and CS-5. Subjects were selected using simple random sampling technique. Serum IGF-1 levels were estimated from blood samples using chemiluminescence immunoassay (CLIA) method. CS was evaluated using a six-stage method of evaluating the cervical vertebrae. Mean IGF-1 levels between the stages were compared by analysis of variance (ANOVA) test.

Results

One-way ANOVA showed highly significant differences between all cervical stages with p value <0.01, but post hoc Tukey test showed highly significant differences between CS-4 and CS-5 with p value 0.006. Serum IGF-1 levels showed good association with skeletal age in male subjects; 53.3% of subjects at CS-3, 66.7% subjects at CS-4, and 6.7% subjects at CS-5 showed IGF-1 levels in peak range.

Conclusions

Serum IGF levels can be used as an additional tool to optimize orthodontic treatment timing.