What is lateral cephalometric radiograph (LCR)?
A lateral cephalometric radiograph is integral to orthodontic treatment planning in many cases and it is important for all dentists to have an understanding of how to interpret them and their uses. Mitchell L, Littlewood SJ, Nelson-Moon ZL, Dyer F. Introduction to Orthodontics (4th Ed).
What is a cephalometric radiograph?
A Cephalometric radiograph is a radiograph of the head taken in a Cephalometer (Cephalostat) that is a head-holding device introduced in 1931 by Holly Broadbent Sr. in USA. The Cephalometer is used to obtain standardized and comparable craniofacial images on radiographic films. Additionally, what is cephalometric imaging used for?
What is lateral cephalometric analysis?
The lateral cephalogram is a profile x-ray of the skull and soft tissues and is used to assess the relation of the teeth in the jaws, the relation of the jaws to the skull and the relation of the soft tissues to the teeth and jaws. What is poor man's cephalometric analysis?
What is the difference between Lateral cephalometric radiograph and natural head position?
Lateral cephalometric radiograph is a radiograph of the head taken with the x-ray beam perpendicular to the patient's sagittal plane. Natural head position is a standardized orientation of the head that is reproducible for each individual and is used as a means of standardization during analysis...
What does a cephalometric radiograph show?
Cephalometric x-rays (also called ceph x-rays or radiographs) show a side view of your head, exposing teeth, jaw, and surrounding structures.
Which of the following is an indication of lateral cephalometric radiography?
Visibility of soft tissue profile is a prerequisite of a lateral cephalometric image. The main indication for cephalometric radiographs is cephalometric tracing—analysis of relationships between teeth and bone based on cephalometric landmarks and performed according to many systems.
What is the meaning of cephalometric analysis?
Cephalometric analysis is the clinical application of cephalometry. It is analysis of the dental and skeletal relationships of a human skull. It is frequently used by dentists, orthodontists, and oral and maxillofacial surgeons as a treatment planning tool.
How important are lateral cephalometric radiographs in orthodontic treatment planning?
Results: The availability of a lateral cephalometric radiograph and its tracing did not make a significant difference to any treatment-planning decisions, with the exception of the decision to extract or not between groups B and C for all 6 patients combined, and between groups B and C and groups B and A for patient 4 ...
What are the advantages of cephalometric analysis?
Cephalometric analysis is an important diagnostic tool for evaluation of dentofacial morphology. It provides a clear image of the skeletal changes that occur in the process of growth and treatment of patients.
How is cephalometric measured?
Traditionally, cephalometric analysis has been carried out using a manual method. An acetate sheet is placed over the radiograph and measurements are recorded of the distances and angles between cephalometric landmarks with a ruler and a protractor.
What can be measured by cephalometric tracing?
Cephalometric analysis can be performed to evaluate the cranial base, the relationship of the maxilla to the cranial base, the mandible's size and position relative to the cranial base, the relationship between the maxilla and the mandible, the vertical dimension, maxillary and mandibular dentition, and soft tissue.
What landmarks are seen on a cephalometric radiograph?
Cephalometric PointsA point (A) The point of the deepest concavity anteriorly on the maxillary alveolus.B point (B) The point of the deepest concavity anteriorly on the mandibular symphysis.Sella (S) The midpoint of the sella turcica (pituitary fossa)Nasion (N) The most anterior point on the fronto-nasal suture.More items...•
What is a lateral cephalogram?
Another useful assessment tool in dental imaging is the lateral cephalogram. This is an x-ray which generates a side view of the head that can provide important information about the teeth and jaw. The lateral cephalogram shows facial structure, bone, and soft tissue.
What are lateral oblique radiographs used for?
The lateral oblique x-ray view of the mandible and maxilla taken on an extra-oral film is a frequently used method for giving a record of the teeth in the buccal segments from canine to third molar show- ing the teeth both erupted and unerupted or to assess the positions of unerupted third permanent molars.
What is a panoramic radiograph used for?
A panoramic x-ray allows us view your head, neck, and jaw, and how they work together as a whole, which means we can more easily identify cysts, tumors, growths, jaw abnormalities, and cancer.
Why do we need cephalometric x-rays?
The information cephalometric x-rays provide is often vital for medical and dental professionals to offer you the best possible care. Cephalometric x-rays may be used for: Dental and orthodontic treatment planning: The use of cephalometric x-rays can expose disease or damage that are difficult or impossible to find during a normal dental ...
Where is the x-ray taken?
This type of x-ray is taken from outside your mouth and does not typically require biting down on any equipment. This view is incredibly useful for many situations as it offers a large field of view, including your teeth, jaw, and profile.
What is ALARA in dentistry?
According to the American Dental Association, professionals follow the As Low As Reasonably Achievable (ALARA) principle to limit the amount of potential harm. According to ALARA, professionals should only recommend x-rays if: The risk of exposure is justified relative to the benefits.
What is X-ray technology?
X-Rays are a technology used in medicine and dentistry that involves directing radiation (x-rays) at an area of the body to create an image of it. Bone and tissue block radiation, causing structures to appear on film or digitally as black, white, and grey. Specially trained professionals are then able to interpret the resulting image.
What is the purpose of x-rays?
Other conditions or injury: As this type of x-ray offers a wide view of your head, neck, and mouth, they may be recommended for various conditions and injuries . According to the American Dental Association, the use of x-rays depends on a patient’s health, age, risk factors, and symptoms.
What is TMD xray?
Temporomandibular disorder (TMD): This condition affects your jaw (temporomandibular) joint, cartilage, or bone and can cause discomfort. Professionals may recommend cephalometric x-rays to diagnose the condition, track changes, or help guide treatment. Other conditions or injury: As this type of x-ray offers a wide view of your head, neck, ...
What is a lateral cephalometric radiograph?
Lateral cephalometric radiograph is a radiograph of the head taken with the x-ray beam perpendicular to the patient's sagittal plane. Natural head position is a standardized orientation of the head that is reproducible for each individual and is used as a means of standardization ...
Why is it important to superimpose a cephalometric radiograph?
Cephalometric radiographs can be superimposed on each other to see the amount of growth that has taken place in an individual or to visualize the amount of movement of teeth that has happened in the orthodontic treatment. It is important to superimpose the radiograph on a stable anatomical structures.
What is computerized cephalometrics?
Computerised cephalometrics is the process of entering cephalometric data in digital format into a computer for cephalometric analysis. Digitization (of radiographs) is the conversion of landmarks on a radiograph or tracing to numerical values on a two- (or three-) dimensional coordinate system, usually for the purpose of computerized cephalometric analysis. The process allows for automatic measurement of landmark relationships. Depending on the software and hardware available, the incorporation of data can be performed by digitizing points on a tracing, by scanning a tracing or a conventional radiograph, or by originally obtaining computerized radiographic images that are already in digital format, instead of conventional radiographs. Computerized cephalometrics offers the advantages of instant analysis; readily available race-, sex- and age-related norms for comparison; as well as ease of soft tissue change and surgical predictions. Computerized cephalometrics has also helped in eliminating any surgeon inadequacies as well as making the process less time-consuming.
What are the points of the craniofacial analysis?
The analysis is based on 5 points: Nasion (Na), Sella (S), Menton (Me), Go (Gonion) and Articulare (Ar). They together make a Polygon on a face when connected with lines. These points are used to study the anterior/posterior facial height relationships and predict the growth pattern in the lower half of the face. Three important angles used in his analysis are: 1. Saddle Angle - Na, S, Ar 2. Articular Angle - S-Ar-Go, 3. Gonial Angle - Ar-Go-Me.
What is cephalometric analysis?
Cephalometric analysis is the clinical application of cephalometry. It is analysis of the dental and skeletal relationships of a human skull. It is frequently used by dentists, orthodontists, and oral and maxillofacial surgeons as a treatment planning tool.
Where is maxillary unit length measured?
The maxillary unit length is measured from posterior border of mandibular condyle (Co) to ANS. The mandibular unit length is measured from posterior border of mandibular condyle (Co) to Pogonion.
Anatomy
- It is very important that prior to tracing the radiograph, it is examined for any pathology. Some of the basic anatomy seen on an LCR is detailed below.
Cephalometric Points
- Below is a list of the most relevant cephalometric points. When starting a tracing, it is important to understand these definitions, and to be able to identify them on a radiograph. A point (A) The point of the deepest concavity anteriorly on the maxillary alveolus B point (B) The point of the deepest concavity anteriorly on the mandibular symphysis Sella (S) The midpoint of the sella tur…
Cephalometric Planes and Relationships
- Planes and relationships are then established using the above points and it is with these that cephalometric analysis can be undertaken. Knowing what these planes and relationships are is key, as well as how they influence diagnosis and treatment planning. SN line The plane demonstrated by a line through the nasion and sella Frankfort Plane The plane demonstrated by …
Interpreting
- Once you have identified the anatomy on the radiograph, traced it and established all the above values and planes, the next step is to attempt to interpret them. This is done to help with diagnosis and treatment planning. In orthodontic assessments, there are 3 planes which are usually assessed; Anteroposterior, Vertical and Transverse relationships. Using the LCR, the Ant…
Overview
Cephalometric analysis is the clinical application of cephalometry. It is analysis of the dental and skeletal relationships of a human skull. It is frequently used by dentists, orthodontists, and oral and maxillofacial surgeons as a treatment planning tool. Two of the more popular methods of analysis used in orthodontology are the Steiner analysis (named after Cecil C. Steiner) and the Downs analysis (named after William B. Downs). There are other methods as well which are listed below.
Cephalometric radiographs
Cephalometric analysis depends on cephalometric radiography to study relationships between bony and soft tissue landmarks and can be used to diagnose facial growth abnormalities prior to treatment, in the middle of treatment to evaluate progress, or at the conclusion of treatment to ascertain that the goals of treatment have been met. A Cephalometric radiograph is a radiograph of the head taken in a Cephalometer (Cephalostat) that is a head-holding device introduced in 1…
Cephalometric tracing
A Cephalometric tracing is an overlay drawing produced from a cephalometric radiograph by digital means and a computer program or by copying specific outlines from it with a lead pencil onto acetate paper, using an illuminated view-box. Tracings are used to facilitate cephalometric analysis, as well as in superimpositions, to evaluate treatment and growth changes. Historically, tracings of the cephalometric radiographs are done on an 0.003 inch thick matte acetate paper …
Classification of analyses
The basic elements of analysis are angles and distances. Measurements (in degrees or millimetres) may be treated as absolute or relative, or they may be related to each other to express proportional correlations. The various analyses may be grouped into the following:
1. Angular – dealing with angles
2. Linear – dealing with distances and lengths
Cephalometric angles
According to the Steiner analysis:
• ANB (A point, nasion, B point) indicates whether the skeletal relationship between the maxilla and mandible is a normal skeletal class I (+2 degrees), a skeletal Class II (+4 degrees or more), or skeletal class III (0 or negative) relationship.
• SNA (sella, nasion, A point) indicates whether or not the maxilla is normal, prognathic, or retrognathic.
Analyses (analytic approaches) by various authors
Cecil C. Steiner developed Steiner Analysis in 1953. He used S–N plane as his reference line in comparison to FH plane due to difficulty in identifying the orbitale and porion. Some of the drawbacks of the Steiner analysis includes its reliability on the point nasion. Nasion as a point is known not to be stable due to its growth early in life. Therefore, a posteriorly positioned nasion will increase ANB and more anterior positioned nasion can decrease ANB. In addition, short S–…
Computerised cephalometrics
Computerised cephalometrics is the process of entering cephalometric data in digital format into a computer for cephalometric analysis. Digitization (of radiographs) is the conversion of landmarks on a radiograph or tracing to numerical values on a two- (or three-) dimensional coordinate system, usually for the purpose of computerized cephalometric analysis. The process allows for automatic measurement of landmark relationships. Depending on the software and h…
Digitization
Computer processing of cephalometric radiographs uses a digitizer. Digitization refers to the process of expressing analog information in a digital form. A digitizer is a computer input device which converts analog information into an electronic equivalent in the computer's memory. In this treatise and its application to computerized cephalometrics, digitization refers to the resolving of headfilm landmarks into two numeric or digital entities – the X and Y coordinate. 3D analysis wo…