Chapter 9: nail structure and growth
What's the average rate of nail plate growth of a normal adult?
1/10-1/8inch per month
what percentage of a healthy nail is water content?
15% - 25%
How long does it take to replace a fingernail?
4-6 months
How many parts make up the nail unit?
7
How long does it take to replace a toenail?
9-12 months
What is nail plate?
A hardened keratin plate that sits on and covers the nail bed
What is nail malformation?
A nail that is abnormal in shape or form
How many layers of nail cells make up the nail plate?
About 100
What do specialized ligaments do?
Attach the nail bed and the matrix bed to the underlying bone.
What are nail folds?
Folds of normal skin that surround the nail plate
What does the bed epithelium do?
Helps guide the nail plate along the nail bed as it grows.
What's the purpose of the hyponychium?
It forms a protective barrier that prevents microorganisms from invading and infecting the nail bed.
What finger nail grows faster and what fingernail grows slowest?
Middle finger grows fastest and thumb fingernail grows the slowest
What do nail folds form?
Nail grooves or furrow, on each side of the nail
What are the parts of a nail unit?
Nail plate, nail bed, eponychium, hyponychium, perponychium, matrix, cuticle, specialized ligaments and nail folds
What makes a nail plate grow thicker?
No product or procedure can make a nail plate grow thicker because a thicker nail plate requires a larger matrix
What affects the growth and appearance of the nails?
Poor health, nail disorder or disease or injury to the matrix
What's the job of the cuticle?
Seal the space between the natural nail palate and living skin above to prevent entry of foreign material and microorganism me and to help prevention hurt and infection.
What affects the growth rate of the finger nails
Seasons, age and pregnancy (hormonal changes)
What is the matrix?
The area where the nail plate cells are formed
What's the difference between the cuticle and the eponychium?
The cuticle is dead tissue adhered to the nail plate and the eponychium is living tissue that grows up to the nail plate
What is the cuticle?
The dead, colorless tissue attached to the natural nail plate
What's the sidewall?
The gold of skin overlapping the side of the nail
What is Natural nail?
The hard protective plate composed mainly of keratin, the fiber-shaped protein found in the skin and hair.
What's the eponychium?
The living skin at the base of the natural nail plate covering the matrix area
What is perponychium?
The living skin bordering the root and sides of the fingernail and toenail
What is free edge?
The part of the nail plate that extends over the top of the finger or toe
What is the nail bed?
The potion of living skin that supports the nail plate as it grows toward the free edge
What is the whitish color on the lunula caused by?
The reflection of light off the surface of the visible part of the underlying matrix.
What is the hyponychium?
The slightly thickened layer of skin under the nail that lies between the fingertip and the free edge of the nail plate
What is the bed epithelium?
The thin layer of tissue that attaches the nail bed to the nail plate
Why are toenails thicker?
The toenail matrix is longer than the matrix found in the fingernails
What's a ligament?
The tough bang of fibous tissue that connects bones or holds an organ in place
What is the lunula?
The visible part of the matrix that extends from underneath the living skin
What's the job of the Matrix cell?
To create nail plate cells
What nails grow fastest?
Toenails
