# Cephalometric Evaluation of Facial Height Ratios and Growth Patterns: A Retrospective Cohort Study
## 2 Materials and Methods
### Procedure Methodology  
#### 2.1.1 Cephalometric Measurements and Protocol  
The cephalometric measurements were performed by a single examiner, following a standardized measurement protocol to ensure consistency across all subjects. Lateral cephalograms were obtained using the same machine, Planmeca Promax(r) (Planmeca, Helsinki, Finland), with subjects positioned in a natural head posture as outlined by [PERSON] [17].  
WebCeph is an orthodontic and orthognathic platform that facilitates cephalometric investigations, end-of-treatment prognosis, preparation for orthognathic surgery, management of patient records, and image preservation.  
We created a free WebCeph system account, and we uploaded a prepared \"jpeg\" cephalometric X-ray image using www.webceph.com and a standard web browser (Google Chrome 64 bit). Each patient was given a unique ID after logging in, and the jpeg files of their cephalometric measurements were submitted. When the operator chose the AI Digitization option, the WebCeph system automatically recognized every anatomical location. After that, WebCeph (AI landmarking) automatically made all of the measurements and downloaded them to the PC. Additionally, WebCeph offered the option to manually correct anatomical landmarks. It was a 10 mm calibration.  
We loaded the digital radiographs stored as jpeg files into WebCeph. The grayscale files had the following image characteristics: 2.232 \(\times\) 2.304 pixels, 8 bits, and 150 dpi. We conducted the computerized analysis on a 14'' screen.  
We conducted the cephalometric analysis using the WebCeph(r) (Korean Intellectual Property Office, Seoul, Republic of Korea, WebCeph, 1.0.0, Assemblecircle, Gyeonggi-do, Republic of Korea) software package for digital tracing and composite cephalometric analysis, incorporating two linear measures and one angular measurement.  
Each digital image was downloaded and saved from a lateral cephalometric radiograph to a Lenovo IdeaPad 5 Pro computer before importing it into WebCeph.  
The key cephalometric landmarks included are as follows:  
* S (sella turcica): located in the middle of the hypophyseal and pituitary fossae.
* N (nasion): the most anterior point of the middle frontonasal suture.
* Go (gionion): the midpoint on the posterior border of each gonal angle, located mediolaterally.
* Me (menton): the lowest point on the chin's curve [25].  
The planes constructed for measurement were N-Me (Nasion to Menton) and S-Go (Sella to Gonion). These landmarks and planes were used to calculate critical parameters such as FHR, which is facial height ratio, TAFH, which is total anterior facial height (N-Me line), TPFH, which is total posterior facial height (S-Go line), and Jarabak's ratio, which may be computed by multiplying the ratio of TPFH to TAFH by 100. The FHR classification categorizes facial morphology into three distinct patterns. The facial height ratio (FHR), or Jarabak's ratio, was derived from these measures, classifying facial growth patterns as follows:  
1. Hyperdivergent: FHR < 59%.
2. Normodivergent: FHR between 59% and 63%.
3. Hypodivergent: FHR > 63% [18].  
FHR is facial height ratio, and TAFH is total anterior facial height (N-Me line); TPFH is total posterior facial height (S-Go line); Jarabak's ratio may be computed by multiplying the ratio of TPFH to TAFH by 100. The FHR classification categorizes facial morphology into three distinct patterns [18].