people.
In the straight profile the LAFH is straight from the nose to the chin.
In the concave profile the LAFH is caved in between the nose and the chin.
Patients with a concave profile should be approached with care when it comes to extractions, as this could make them even more concave, whereas convex profile patients would benefit from this.
Figure 2.8 The different profile patterns.
2.3 Intra‐Oral Assessment
There are many stages considered when carrying out an intra‐oral assessment. The first three look at the three planes of space, whereas the remaining eight look more into how the dentition appears in the mouth.
2.3.1 Anterio‐posterior Plane
Assesses the arch from front to back.
This stage looks at the different types of relationships of the occlusion, such as molar relationship, incisor relationship, canine relationship, and overjet.
Molar relationship:Also known as Angle’s classification.Looks at the position of the upper first molars.Classification is class I; class II, II25, II50, II70; and class III, III25, III50, III70.
Incisor relationship:Also known as the BSIC (British Standards Institute Classification 1983).Looks at the position of the incisors.Classification is Class I; Class II div I, div II; and Class III.
Canine relationship:Looks at the position of the canines.Classification is class I; class II, II25 II50, II70; and class III, III25, III50, III70.
Overjet:Distance between the upper and lower teeth within the horizontal plane. The distance between them is measured with a stainless‐steel ruler.
2.3.2 Vertical Plane
Assesses the arch up and down.
Looks at the overbite.
The overbite is the vertical overlap of the upper incisors over the lower incisors when the posterior teeth are in occlusion. It can be measured as:Average: upper incisors cover one‐third of the lower incisors when in occlusion.Increased and complete: upper incisors cover more than one‐third of the lower incisors, but are complete (touching) on hard or soft tissues when in occlusion.Increased and incomplete: upper incisors cover more than one‐third of the lower incisors and are incomplete (not touching) on hard or soft tissues when in occlusion.Decreased and complete: upper incisors cover less than one‐third of the lower incisors, but are complete (touching) on hard or soft tissues when in occlusion.
Decreased and incomplete: upper incisors cover less than one‐third of the lower incisors and are incomplete (not touching) on hard or soft tissues when in occlusion.
2.3.3 Transverse Plane
Assesses the arch from side to side.
Looks for any posterior crossbites.
A posterior crossbite is found when the upper dentition on the posterior segment sits within the lower teeth when occluding.
There can be unilateral or bilateral crossbites, unilateral meaning on one side of the arch and bilateral being on both sides of the arch.
2.3.4 Crowding
This assesses the amount of crowding there is within both the upper and lower arches.
Assessing the crowding falls into the category of space analysis.
Constructing an archform that best fits the majority of the teeth can help analyse how much crowding there is within the arch.
Once the archform has been constructed, it is then measured by the use of floss and a stainless‐steel ruler. Once the measurement has been calculated for that, the mesiodistal widths of all the teeth within that arch are measured. The calculations are then taken away from each other, which gives you the total amount of crowding:
Crowding is then classified as the following:Mild crowding: 2–4 mmModerate crowding: 4–8 mmSevere crowding: 8+ mm.
2.3.5 Spacing
This assesses the amount of spacing that is present within the two arches.
Spacing can be classified into mild, moderate, or severe.
Spacing can be found within the arch due to the following:Extractions: patients who have previously had extractions, for example extracted LL6.Dento‐alveolar disproportion: patients who have big arches but small (microdontia) teeth can present with spacing between the teeth.Microdontia: patient who present with small teeth, for example peg laterals.Diastema: patients who present with a diastema within the arch, which could be due to a habit such as thumb sucking, active tongue thrust, or a mesiodens lying erupted or unerupted between the upper central incisors.
2.3.6 Path of Closure
This assesses how the patient bites the teeth together.
When assessing the bite we look at:Is there any deviation of the mandible on closing?Does it shift left, right, or forward to gain a comfortable bite?
2.3.7 Teeth Present/Missing
This will look at how many teeth there are.
Patients can present with missing teeth or extra teeth.
Missing teeth could be for numerous reasons:Hypodontia casesPrevious extractionsImpacted teeth.
Extra teeth could be due to supernumerary teeth such as:Conical teeth, also known as mesiodensTuberculatesSupplemental teethOdontomes.
2.3.8 Habits
This stages assesses if the patient has any habits that may affect the teeth, such as thumb sucking or a tongue thrust.
It is important to establish whether the patient has a relevant habit or not prior to treatment starting.
All habits must be ceased before orthodontic treatment can be commenced, as continuing could increase the length of treatment and, more importantly, result in relapse at the end of treatment.
2.3.9
