Excessive Downward Displacement and Insufficient Downward Displacement
Here on, we will use interchangeably the terms vertical maxillary excess and deficiency with excessive and insufficient downward displacement. In order to understand its manifestations, we need to account for key landmarks such as:· Columella (CM)– The tissue that links the nasal tip to the nasal base, separating the nares. The inferior margin of the nasal septum
· Subnasale (SN) – the junction of the upper lip and the columella
· Stomion Superios (Sts) – the lower most point on the vermillion of the upper lip
· Stomion (Sto) – The point of contact, when lips are competent, in the midline, between the top and bottom lip
· Stomion Inferious (Sti) – the upper most point on the vermillion of the lower lip
· Soft tissue mention (Me) – The most inferior point on the soft tissue outline of the chin
The measurements of the upper lip and lower lip for each patient are ascertained by using the aforementioned landmarks. The length of the upper lip is measured from Sn to Sts. In a typical male and female this measures to 24mm and 21mm respectively (REF). The length of the lower lip is measured from Sti to Me. In a typical male and female this measures to 50mm and 46.5mm respectively.When considering EDD and IDD, the class of the skeletal base is a good adjunct. In other words, EDD and IDD can either appear camouflaged or apparent given the skeletal base and the soft tissue profile accompanying it.
Signs and symptoms
Individuals with jaw abnormalities have both functional and aesthetic impairment.Misalignment of teeth creates difficulties in head and neck functions related to chewing, swallowing, breathing, speech articulation and lip closure/posture.Affected individuals may also experience TMJ pain and dysfunction, which negatively affect the quality of life.A proportion of affected individuals also have psychological problems. Diagnosis
Diagnosis of a jaw deformity is a structured process, linking the undertaking of a history, physical examination of the patient, and appraisal of diagnostic studies. This process may involve more than a single discipline of Dentistry – in addition to orthodontic and surgical needs, some patients may also require periodontal, endodontic, complex restorative, and prosthetic considerations.It involves the chief presenting complaint of the patient, which allows the clinician to understand the patients perception of the problem – what they think the problem is and what they would like corrected. The patient may find eating difficult or may have problems with speech or the appearance of the teeth or face. However, patients may be hesitant to discuss dissatisfaction with their appearance because they may feel that it is more acceptable to present a functional problem to the clinician. For this reason it is important to reassure patients that their aesthetic problems and the effects of these are perfectly valid concerns. In children, psychological development can be affected due to teasing if they have abnormal appearance of teeth or face. Correction of the abnormality can be extremely beneficial to the patient.