81018 Growth & development of the childrens

growth

1. FACTORS AFFECTING GROWTH,GROWTH SPURTS AND GROWTH PATTERN

2. INTRODUCTION VARIABILITY OF GROWTH No two individuals are exactly alike & no two individuals grow in the same pattern

3. FACTORS AFFECTING GROWTH

4. HEREDITY - Phenotype - Characteristics of Parents - Race - Sex - Genetic disorders

5. HEREDITY The basic control of growth,both in magnitude and timing is located in the gene. The potential for growth is genetic . The actual outcome of growth depends on the interaction between the genetic potential and environmental influences. Body size,shape ,deposition of fat and pattern of growth are under genetic control. Eg: The marked advancement of girls over boy in the rate of maturation is attributed to the delaying action of the Y chromosome in males

6. CHARACTERISTICS OF PARENTS Offsprings take the characteristics from parents ( Height,weight,facial characteristics etc.) RACE Growth potential of children of different racial grups is different Eg : African , American, Asian .

7. Girls mature faster than boys. Pre pubertal growth spurt occurs earlier in girls SEX

8. GENETIC DISORDERS Growth & development are adversely affected by genetic disorders. Chromosomal abnormalities: Turner syndrome , Down syndrome etc. Gene mutations: Eg : Metabolic defect- Mucopolysaccharidosis etc.

9. ENVIRONMENTAL PRENATAL NATAL POSTNATAL

10. PRENATAL CAUSES

11. MATERNAL FACTORS 1.Poor maternal health: Systemic disease like renal , cardiac , diabetes , hypertension affects fetus due to altered blood flow. 2.Maternal diet & infection: Important nutrients: calcium,phosphorus,iron,folic acid,vitamin B,C,D . Placental insufficiency may occur due to poor nutrition of mother. Congenital infections can affect child growth: Eg . Rubella, syphilis,HIV,HSV,toxoplasmosis .

12. TERATOGENS Agents which cross the placental barrier and produce embryologic defects- teratogens .

13. DEVELOPMENTAL ANOMALIES DOWN’S SYNDROME CLEFT LIP AND PALATE HEMIFACIAL HYPERTROPHY PIERRE ROBIN SYNDROME ECTODERMAL DYSPLASIA CROUZON SYNDROME

14. NATAL CAUSES 1.Trauma during birth Forceps delivery can damage TMJ and cause ankylosis of TMJ which results in retarded growth of mandible( Micrognathia )

15. 2.Intrauterine moulding During IU life, any pressure effect on rapidly growing areas leads to growth distortion Sometimes, fetal head is flexed tightly against chest in utero.This retards the mandibular growth and in turn forces the tongue upwards & hence CLOSURE OF PALATE IS STOPPED leading to CLEFT PALATE EG:PIERRE ROBIN SYNDROME

16. POSTNATAL CAUSES

17. ENDOCRINE DISTURBANCES Hormones responsible for growth: GroupI : Influence skeletal growth Growth hormone,Insulin,thyrotrophic hormone Group II: for long bone ossification. Parathormone Group III: for pubertal growth spurts Androgen,progesterone,estrogen . Group IV: Prolactin Deficiency of any of these hormones results in impaired growth. Eg : Hypothyroidism,dwarfism,Hypoparathroidism

18. NUTRITIONAL DEFICIENCY This can lead to arrested development & faulty bone formation. Conditions like scurvy,rickets,hypocalcemia vitamin B deficiencies can result in retarded growth.

19. FUNCTIONAL CAUSES Faulty head posture,Mouth breathing,tongue thrusting,thumb sucking,functional shifts This can lead to retarded growth of jaws resulting in malocclusion. Mouth breathing can result in long face syndrome. Thumb sucking causes anterior open bite,narrowing of maxilla.

20. MUSCULAR ACTIVITY Muscles influence jaw growth by : Formation of bone at muscle attachment Loss of muscle due to injury results in underdevelopment of that part Excessive contraction – restricts the growth.

21. Illness Minor illness has no effect on growth Systemic disease has an effect on child growth. Climate & seasonal effects - Cold climates – more adipose tissue - Growth increases during night time due to increased release of hormones - Increase in height during autumn - Increase in weight during spring.

22. Socioeconomic factors- C hildren living in favourable conditions tend to be larger & show earlier onset of growth events. Exercise - useful in development of motor skills - increase in the muscle mass, - for general well being & fitness.

23. Family size & birth order : T he maturation levels of achievement & in their intelligence can be correlated with it. Psychological disturbances children experiencing stressful conditions display an inhibition of growth hormone.

24. Developmental growth periods A. Prenatal life (about 10 IU months) 1.Period of ovum : conception to 2 weeks 2.Period of embryo:2-8 weeks 3.Period of fetus:2 to 10 IU months B.Birth C.Postnatal life 1.Infancy :( birth to about 1 year) a.Neonatal period:birth,1 to 2 weeks b.Infancy period:2 weeks to 1 year 2.Childhood a.Early childhood (preschool) 1-6 years b.Middle childhood(grade school) 6 to 9 or 10 years

25. c.Late childhood or prepubertal period(junior high school) Girls:9 or 10 to 12 or 15 years Boys:9 or 10 to 13 or 16 years 3.Puberty a.Girls mean about 13 years b.Boys mean about 14 years 4.Adolescence a.Girls:13-18 years b.Boys:14-20 years 5.Maturity: 18 or 20 to about 60 years 6.Senility: beginning at about 60 years

26. Normal features of Growth & Development Pattern -Differential Growth - Cephalocaudal gradient of growth Variability Timing, rate & direction

27. PATTERN Pattern in growth represents proportionality It refers not just to a set of proportional relationships at a point in time, but to a change in these proportional relationships over time.

28. 28 RHYTHM OF GROWTH Human growth is not a steady and uniform process wherein all parts of the body enlarge at the same rate and the increments of one year are equal to that of the preceding or succeeding year. (Hooton)

29. 29 RHYTHM OF GROWTH First wave of growth - Birth to 5-6 th year Slow increase terminating in Boys 10-12 th year Girls 10 years  

30. 30 Next period of accelerated growth terminating in- Girls 14-16 years Boys 16-18 years Final period of growth terminating in- Girls 18-20 years Boys 25 years

31. DIFFERENTIAL GROWTH Different organs grow at different rates to different amount and at different times. Reasons for differential growth include Cephalocaudal growth, Scammon’s growth.

32. SCAMMON’S GROWTH CURVE Lymphoid tissues attain a 200% growth by the age of ten and then regress afterwards. Neural tissue attains full growth by the age of six and then stops. General tissues follow a sigmoid growth pattern. Genital tissue grow significantly only at puberty and achieve full growth at about 20 yrs of age. 32 .

33. EFFECTS OF SCAMMON’S GROWTH CURVE IN FACIAL REGION Mandible It follows somatic growth pattern Long time growth until about 18-20yrs Maxilla Follows neural growth pattern Growth ceases earlier Hence, skeletal problems of maxilla should be treated earlier to mandible .

34. 34 CEPHALO-CAUDAL GRADIENT OF GROWTH It means that there is an axis of increased growth extending from head towards the feet. Head - Head takes up ab out 50% of the total body length around the 3 rd month of I.U. life. At birth – 30% of body length In an adult – 12% of total body length

35. 35 CEPHALO-CAUDAL GRADIENT OF GROWTH

36. 36 Ø   Lower Limbs – These are rudimentary around 2 nd month of I.U. life In an adult - 50 % of total body length. Ø    At Birth , cranium is proportionally larger than the face. Post- natally , the face grows more than the cranium.

37. 37 GROWTH SPURTS Ø Period when sudden acceleration of growth occurs Physiological alteration in hormonal secretion is the believed cause of growth spurts.

38. GROWTH SPURTS WOODSIDE (1968)

39. 39 Timings of growth spurts BJORK (1975)

40. 40 CLINICAL SIGNIFICANCE Growth modification by means of functional and orthodontic/orthopedic appliances elicit better response during growth spurts . During pubertal growth spurts,there is change in growth direction from vertical to horizontal. Surgical correction involving the maxilla and mandible should be carried out only after completion of growth spurts.

41. CONCLUSION A better treatment is rendered by predicting,modifying,correcting or intercepting growth . Understanding growth is difficult, yet fruitful to the clinician

42. THANK YOU