To understand the hairline, one must have reviewed 100 s of natural non receded hair lines. One should also have complete knowledge of different racial hair lines and should have complete understanding of the height and width of the facial bony structures. These bony structure measurements in different races, determine the unique shape of the racial hair lines.
Vertical Facial dimensions
The face is divided into three parts. In generality the lower part is the largest in all races, the middle part is in the middle. The upper part is the smallest.
1- Upper part
2- Middle part
3- Lower part
1- Upper part
The upper part of the face is between hairline and the eyebrows. The height of the upper part is smallest of all the three facial heights. In Caucasians and Chinese the height of the upper part is almost same 5.7 cm. In Afro it's 0.5 cm more than the Caucasians and Chinese, its 6.18 cm. The vertical height of the upper parts provides a good parameter for restoring the height of the lost hairline. As the upper part in afro has more height, so do the hairline. On an average Afro hairline is 0.5 cm higher than Caucasians and Chinese.
2- Middle part
The middle part of the face is between eyebrows and the lower base of the nose. The height of the middle part of the face is almost same in all three races, it’s an average 6.7 cm.
3- Lower part
The lower part is between lower base of the nose and the chin. The height of the lower part of the face is largest of all the three facial heights in all the races. In Caucasians and Chinese the height of the lower part is almost same 7.25 cm. In Afro the height of the lower part is 0.5 cm more than the Caucasians and Chinese, its 7.75 cm.
Horizontal Facial Dimensions
In horizontal facial dimensions, four measurements are important.
1- Width of the head
2- Width of the eyes
3- Width of the mandible
4- Width of the jaw
Generally for every race , head is the widest , mandible is less wider than the head and jaw is the less wider than mandible . In Chinese, Head, Mandible and Jaw widths are the largest among all three races. In Afro, Head, Mandible and Jaw widths are smallest among all three races. In Caucasians, Head, Mandible and Jaw widths are in the middle among all three races.
The width of the eyes is least for Caucasians, in the middle for the Chinese and the most for Afro. Except for the width of the eyes, which is the widest in Afro, rest of the widths in Afro is the smallest among all the three races.
General Shape of the Skull
First of all a horizontal level is established at the level of eyebrows on the front , top of the ears on the sides and posterior pole of the skull on the back . Skull moves straight upward circumferentially from this level for an average 5-6 cm with 15 degree inward inclination. Above the vertical part Skull is Dome shaped and this part is called calvarium. Average height of the calvarium is 3-4 cm. Where the vertical part of the Skull end, it curves inward for an average 1 cm, this part is called lower transition zone of calvarium. After the transition zone, calvarium part of the Skull moves up 2-2.5 cm at an average 45 degree, at this point skull again curves inward to create an upper transition zone and become flat at top.
To create Frontal hair line inconsistent with person racial features does not look natural. Knowledge of different bony features and their measurement is extremely important to restore the unique individual hairlines.
Hair line is based on two important points.
1- Frontal Midpoint
2- Apex of Fronto Temporal Angle
There are two criteria based on Facial Dimensions to mark the Frontal Midpoint.
First Criteria for Marking the Frontal Midpoint
1-The Average height of the vertical part of the forehead is 5.7 cm. In Afro it's 0.5 cm higher. The Vertical part of the forehead moves up average at negative 15 degree angle and ends into lower transition zone of the calvarium. The height of lower transition zone of calvarium is an average 1 cm. Frontal Midpoint is marked in the middle of this transition zone. These general measurements give an idea about the height of the hairline from the eyebrows. Based upon the above general measurements average height of the hair line in Caucasian and Chinese is 6.5 cm and in Afro is 7 cm.
Second Criteria for Marking the Frontal Midpoint
2- Facial height is measured from eyebrows to the chin, if it's 13 cm, take half of that, 6.5 cm, to mark the frontal midpoint.
Apex of Fronto Temporal Angle
Frontal and temporal hairline meet at outer canthal plane to create fronto temporal angle, where they meet is called Apex of fronto temporal angle.
Locating The Missing Apex of Fronto Temporal Angle
Apex of Fronto Temporal Angle can be located by using two landmarks
1- Outer bony rims of the eyes
2- Begining of the Lateral Calvarium
1- Role of outer bony rims of the eyes in locating apex of fronto temporal angle
Width of the eyes plays very important role. A vertical line is drawn at the outer bony rim of the eyes, intersect this vertical line with the tangential line, drop this tangential line at right angle to the vertical line. Where this tangential line touches the skull, it’s the plane for the Apex of Fronto Temporal angle, also called outer canthal plane. Once the Outer canthal plane is located, next is to mark the Apex location on this plane. A vertical line is drawn in front of the ear, where this line intersects with the Outer canthal plane, it is marked. From this marked point move forward on Outer canthal plane 2 cm, mark this point, it's the Apex of fronto temporal angle.
2- Role of beginning of lateral calvarium in locating the apex of fronto temporal angle
Temporal and Parietal skull moves up vertically from ear ,after an average 6 cm it start curving inward for an average 1 cm called the lower transition zone of the calvarium . Outer canthal plane lies in the middle of this transition zone. Next is to mark the Apex location on this plane. A vertical line is drawn in front of the ear, where this line intersects with the Outer canthal plane, it is marked. From this marked point move forward on the Outer canthal plane 2 cm, mark this point, it's the Apex of fronto temporal angle.
Restoring The Hairline by Joining the Frontal Midpoint and Apex of Fronto Temporal Angle
Once the frontal midpoint and apex of fronto temporal angle is marked, join these two points at the level of middle of lower transition zone. It creates a shape of semicircle. Depending on different racial head widths, it create an Oval hairline for caucassians, round for Chinese and broad flat hairline for Blackes.
The average length of the hairline semicircle is 16 cm. The average length of half of this semicircle from frontal midpoint to the Apex of fronto temporal angle is 8 cm. If this length ranges between 7 to 9 cm, frontal hairline aesthetically looks very good. If you join two apex points to create a coronal line, the average distance between frontal midpoint and this line is 6.5 cm in saggital plane.
Once the hairline is drawn based on bony features of the skull and face, it is discussed with the client. Hairline is reviewed in mirror first by standing behind the client and then standing on each side of the client. The hairline is even and symmetrical when viewed from the front and the back. From side view hairline should look horizontal and with very little forward lower inclination. The Apex point should never be lower than the Frontal point on profile in horizontal plane. Pictures of the drawn hairline are reviewed .Client previous pictures are reviewed. Minor Adjustments are made on the request of client. Minor adjustments are also made based on the unique individual features.
Once after the discussion with the client, hairline is decided, minor irregularities are made in it.
Transition zones of gradual increase in the density are marked. A line is marked 3-4 mm behind the decided hairline, single hair follicular units are planted in this zone in a irregular pattern of planting 1cm wide and leaving 1 cm wide without planting. An average low density of 20 single hair follicular units per cm square is achieved. Another line is drawn 3-4 mm behind the single follicular units. An average density of 30-40 single follicular units per cm square are achieved in this zone. In these two zones of single hair follicular units, perpendicular sites at 20 degree angle with forward direction are made, as the hair move from frontal midpoint toward the Apex point, hair fans out outside. Another 1 cm deep zone is drawn behind these two zones of single hair follicular units, in this zone two hair follicular units are used in perpendicular sites at an average 30 degree angle. Behind the two hair follicular units zone three hair follicular units are used. As this zone move back from frontal area to Mid Scalp area, the sites angle gradually increases from 30 to 60 degree.
Restoring the temporal hair line.
In the temple area the non receded Temporal hairline start at outer canthal plane , an average 4 cm in front of the pretragal vertical line , the temporal hairline extend down and forward at 45 to 60 degree angle up to the vertical outer canthal line , to create temporal peak . Non receded temporal peak is an average 1.5 cm higher than the eyebrow. From temporal peak temporal hairline extend down and backward at 45 to 60 degree angle and continue with the sideburns. Temporal hairline also recedes in hair loss. Temporal hairline recedes backward in Class 2-4 hair loss. In Class 5 to 7 hair loss, temporal hairline also recedes downward from outer canthal plane and temporal peak is lost.
If donor area allows, restoring the temporal hair line compliment the frontal hair line and make a complete hair line restoration.
If the temporal hairline has dropped below the outer canthal level, as in class 5-7 hair loss. If the donor area allows, this lost temporal hairline can be restored.
Draw a vertical line just in front of ear, where this vertical line intersect the outer canthal plane, mark that point. Mark another point 2 cm in front of it. Connect the receded temporal hair line to this point. To restore the temporal peaks, first try to find the traces of temporal peak, and restore it. If there is no trace of temporal peak, mark the new temporal peak .The average height of temporal peak from Frankfort horizontal line is 4.5 cm or 1.5 cm above the eyebrow level. Mark outer canthal line. Draw another vertical line parallel to the outer canthal line 1.5 cm behind it. Draw a horizontal line parallel to frankfort line at an average 4.5 cm height , Where this line intersect the vertical line behind the outer canthal line mark this point , it's the apex of temporal peak . Drop the temporal hairline down and forward from the apex of fronto temporal angle at 45 degree to join the marked apex of temporal peak. From apex of temporal peak drop the temporal hairline down and backward at 45 degree angle to join the sideburns.
Once the marking is done, perpendicular sites at 10 degree angle are created in backward direction. Symmetrical irregularities are created just like the frontal hairline. Temporal hair line is restored by single hair follicular units.
Frontal and Temporal hair lines are restored independently and they meet at the outer canthal plane, the joining of these two hairlines at the outer canthal plane is called Apex of fronto temporal triangle.
Frontal hair line should not chase the receded temporal hair line, below the level of outer canthal plane, a common mistake, which should be avoided. Most common aesthetically bad hairlines can all together can be avoided, if the frontal hairline marking simply stays circumferentially horizontal along the lower transition zone of calvarium.
If donor area allows restoring both frontal and temporal hairline complement each other and provides the aesthetically great hair restoration.