DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

1. INTRODUCTION  :

Although vertical dimension anomalies are often associated with other sagittal or transverse dimension anomalies which make clinical cases more complex, they are often forgotten during management by the orthodontist. This implies the evaluation of the vertical dimension before, during and after orthodontic treatment.

2. ALVEOLAR ANOMALIES IN THE VERTICAL DIRECTION:

THE SUPRACLUSION:

It is a vertical alveolo-dental anomaly located in the anterior alveolar sector and characterized by excessive incisal overlap (more than 3mm)

Clinical forms:

Anomaly most often symmetrical, uni or bi maxillary.

• in the maxilla: located at the level of the two central incisors, lower than the maxillary occlusal plane, at the level of the four incisors or the incisor-canine sector.
• In the mandible: located at the level of the four incisors or the incisor-canine sector.

This anomaly can be isolated (alveolar) or associated with horizontal growth (short face, basal anomaly)

Facial signs  :

• little or no aesthetic impact
• lip occlusion is usual
• we sometimes observe an eversion of the lower lip downwards, with an accentuated labio-mental groove due to the support of the upper incisors
• if the overbite is of maxillary origin, the free edge of the upper incisors is sometimes too low in relation to the stomion (M = 2.5 mm)
• if the anomaly is of basal origin, the lower level of the face appears diminished

Occlusal signs:

• excessive incisal overlap 
• the free edges of the lower incisors in ICM can come into contact with the cingula of the upper incisors or with the palatine mucosa
• bimaxillary overbite in case of lingo version associated with the upper incisors, contact with the lower vestibular gingiva

Teleradiographic signs:

In the alveolar form we have an associated biproalveolia or biretroalveolia 

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

Etiologies:

Most often it is an anomaly of primary origin:

Dento-dental disharmony due to maxillary excess

Abnormal increase in the coronoradicular angulation of the upper incisors

Below average vertical development of the posterior alveolar bone, associated with horizontal growth pattern/antero-posterior shift

Associated anomalies:

Overbite is observed in all Angle classes, particularly in class2 div1 of the short face type without deforming habits, and in class2 div2 systematically and in some class III

THE INFRACLUSION:

Definition  :

It is an anomaly of the vertical direction located in the anterior or lateral alveolar-detal sector characterized by an insufficiency or absence of incisal coverage; we can also use the term open bite.

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

Clinical forms:

It affects the alveolo-dental area anterior to the maxilla or the mandible or both at the same time, the gap can be symmetrical or asymmetrical or incorporate or not the canines, depending on the importance of the anomaly

The anterior functional gap:

It is not associated with a major abnormality of the skeletal bases in the vertical direction, dysfunctions and parafunctions constitute the most frequent etiology.

1. distorting habits:

Digital sucking, cloth biting tic, lower lip suction with suction

2. atypical lingual form or function:

Previous usual situation, large volume

Primary swallowing with lingual interposition linked to low lip tone

3. ventilation disorders:

Lowering and advanced tongue position required by mouth ventilation

4. speech disorder:

Very inconsistent, lack of articulation of consonants

The lateral functional gap:

Definition  :

Absence of dental contacts in ICM at the level of the cuspid teeth; 1st ^or 2nd ^molar excluded and incisal contact

etiology:

Absence of alveolar bone formation at the molar level

Lateral lingual interposition in function or at rest

A large and broad tongue 

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

3. BASAL ANOMALIES OF THE VERTICAL SENSE:

Basal anomalies of the vertical direction currently pose problems and complicate an anomaly of the sagittal or transverse direction, thus darkening the prognosis and limiting our therapeutic conduct.   

ANTERIOR VERTICAL EXCESS – HYPERDIVERGENCE – OPEN BITE: 

The aesthetic impact is so significant that it prompts the patient to consult.

We generally observe an obstruction of the upper airways, behavioral abnormalities will darken the prognosis of this unsightly clinical picture.

Positive diagnosis:

As a rule, facial examination reveals at first ^glance a special elongation of the lower floor in the vertical direction accompanied by skeletal distoversion.

From the front  : The aesthetic impact is very important.

• The height of the lower floor is very excessive (excessively long face).  
• The transverse diameters of the face are often very small compared to the vertical dimensions.
• The cheeks are usually tight and thin.
• The nostrils are narrow and pinched, a small nose with a reduced distance between the wings of the nose.
• The upper lip is thin, the lower lip is fleshy and everted with an unsightly appearance, often there is labial inocclusion, in this case the teeth are visible.
• Contraction of the muscles of the chin tuft to ensure forced mouth closure, which gives the chin an orange peel appearance.
• The patient lets his mandible hang.
• In cases without a gap, the upper teeth are visible, which will give a gummy smile. Otherwise, they are often hidden by the upper lip, which consequently gives a toothless smile.

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

In profile:

• Presence of strong skin convexity.
• The upper and middle floors are normal.
• Posterior rotation causes an imbalance between the anterior facial height which is increased and the posterior facial height which is decreased.
• Depending on the increase in the lower floor, the nose appears longer, this impression can be accentuated by a backward-leaning (receding) forehead and a pronounced nasal saddle.
• The chin is receding, erased, pointed at the bottom instead of being pointed at the front.
• The goniac angle is open, often with an accentuation of the pre-goniac notch (on palpation).
• The rising branch appears short. 

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

Examination of occlusion:

Intra-arcade layout  :

• The maxillary arch appears reduced in these transverse dimensions (often V-shaped).
• The Spee curve is greatly exaggerated for gaping cases.
• The mandibular arch is normal and sometimes presents a slight anterior crowding.    

Inter-arcade relationship  :

Static  :

Antero-posterior direction  : Examination of the occlusion in this direction gives results which vary depending on the associated malformation, by the appearance of Class II or Class III, biproalveoli and endognathia, the latter particularly aggravating this tendency.   

Vertical direction: There may or may not be an anterior gape; in severe cases the gape is anterior and extends laterally.

Transverse sense  : For cases with open bite, maxillary endognathia is frequent and is characterized by a bilateral reverse bite without laterodeviation or a unilateral reverse bite with associated laterodeviation. 

Kinetics  :

There is a gap between the RC and the ICM of more than 1mm. 

Functional signs:

Phonation: disturbed, sometimes rhinolalia.

Chewing: Incision is practically impossible through the incisors (gap).

Swallowing: primary type, non-tight arch, often with lingual interposition.

Breathing: The frequency is significantly increased in high and medium respiratory obstructions with nocturnal or permanent mouth breathing.

Cephalometric signs:

It highlights the divergence of the face accompanied by the divergence of one or more of these levels, thus reflecting the imbalance between the anterior and posterior regions of the face:

• There is an increased height of the lower floor, it is greater than 55%.
• The FMA angle is increased, it is greater than 22° +/- 6
• The y-axis angle is increased, it is greater than 59° 
• ENA-XI-Pm > 47° +/- 4°. (Dolichofacial).
• The facial axis is decreased, CC-Gn / Na-Ba < 90° +/- 3.5° (posterior facial growth direction).

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

Differential diagnosis:

Between EVA (anterior vertical excess) and EVT (total vertical excess).

Between EVA and posterior insufficiency

Etiopathogenic diagnosis:

The etiopathogenesis of vertical skeletal excess is very complex because it is often multifactorial; we can distinguish:

Hereditary factors:

Vertical excess:

From cephalometric analyses of hereditary variations, some authors have observed a strong correlation between parents and children at the level of 03 dimensions:

• The base of the skull.
• The length of the mandibular body.
• The total facial height.

Statistically, transmission is more important between father and children, particularly for mandibular dimension, while it is facial height that seems to be the most transmitted between mother and children.

Watnick, who studied the heredity of craniofacial structures, concluded that the vertical direction is much more hereditarily transmissible than the sagittal direction.

Functional disorders:

They play an important role in the installation of vertical dysmorphosis by excess.

Respiratory disorders:

Ricketts, the first to describe obstructive pulmonary syndrome, noted the following signs:

• Dental and skeletal gape associated with posterior rotation of the mandible.
• Lateral crossbite, most often molar.
• Presence of hypertrophic adenoids or tonsils.
• Lingual interposition during swallowing.
• Mouth breathing.

Lingual interpositions:

The association of lingual interposition and anterior vertical excess is very common.

The functional mechanisms that can produce posterior rotation of the mandible are multiple and complex. 

Lingual interposition can be of primary or secondary etiology.

Primary etiology:

It can exist in:

• Macroglossia in Down syndrome.
• Anomalies of shape or position.
• Functional anomalies, particularly lingual suction, producing a chain reaction, incisive version, procheilia or gaping lips, change in position of the soft palate which will result in mouth breathing.     

Secondary etiology:

It may be caused by various disorders of various origins:

• Presence of enlarged adenoids or tonsils causing respiratory obstruction.
• Thumb or finger sucking.
• occlusion disorders: The presence of painful cuspal interferences can cause a relieving lingual interposition which installs a lateral open bite.

 VERTICAL INSUFFICIENCY OF THE MAXILLA (IVM):

These anomalies correspond to an accentuation of the short face type and are revealed by clinical examination.

This type of anomaly is as socially poorly perceived as a hyperdivergence; it is sometimes the functional impact of the inter-arch relationships (e.g. overbite) which leads the patient to consult.

Positive diagnosis:

Facial signs:

From the front  : 

• The lower floor appears very small on a face of normal length and wider than average.
• The lips are long, thin and tight with the presence of stomion.
• The lower lip has a very marked labiomental groove with eversion of the latter.
•  The upper lip covers the entire height of the vestibular surfaces of the upper teeth, sometimes giving a completely toothless appearance when smiling.
• On the contrary, some class II 2 cases present a gummy smile resulting from the antero-superior supra-alveolism.
• A broad nose base with well-developed nostrils.

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

In profile:

• Imbalance between the anterior facial level and the posterior facial level.
• The profile is concave if the lips are thin, and convex if the lips are long and everted.
• The chin is prominent in profile.
• The goniac angle is closed.

Functional signs: 

• The elevator muscles are very developed.
• The masseters are prominent, powerful, and generally anteriorly inserted.
• The depressor muscles may have low tone.
• Lip tone is generally very important.
• The chin muscles are very powerful.
• There may be functional disorders of the atypical swallowing type with loose arches and posterior lingual interposition and sometimes the orbicularis of the lower lip (slinging action).

Occlusal signs:

Inter-arcade layout:

• In the anteroposterior direction, class II relationships are frequent.
• In the vertical direction, the overbite is constant.
• Traumatic palatal lesions are sometimes observed in severe cases.
• The transverse direction is normal or excessive lower linguoclusion which aggravates the incisor overbite.
• The free space of inocclusion is increased in all cases: this is a pathognomonic sign.

Teleradiographic signs:

• There is a reduced height of the lower floor, it is less than 55%.
• The FMA angle is reduced, it is less than 22° +/- 6° (anterior mandibular growth direction).
• The y-axis angle is decreased, it is less than 59° (anterior facial growth direction).
• The height of the lower floor of the face is reduced, ENA-XI-Pm < 47° +/- 4°.
• The facial axis is increased, CC-Gn / Na-Ba > 90° +/- 3.5° (anterior facial growth direction).
• ENA-Me < So-ENA: Open bite.

Differential diagnosis:

• These anomalies can be confused with:
• Alveolar anomalies in the vertical direction:
  • Molar infra-alveolus.
  • Supra-alveolus.
  • Lateral functional gap.
• With lateral condylar hypergrowth syndrome: there is mandibular hypergrowth with:
  • A massive mandible.
  • Lengthening of the condyles.
  • Long horizontal branches.
  • A closed goniac angle.
  • A pronounced symphysis.

 Etiological diagnosis:

• Hypodivergence is usually hereditary.
• This anomaly is associated with a particular muscular anatomy and a generally hereditary muscular power.
• The pterygo-masseterine strap is wide, powerful and inserted anteriorly (crushes the skeleton).
• The forces act mainly on the occlusal pads so condylar growth continues leading to advancement of the chin. 

4. Conclusion :

Any possible abnormality of the vertical direction must be assessed during a careful clinical examination and treated as early as possible in order to obtain better aesthetic and functional results.

The basal or alveolar origin should be easily diagnosed by the orthodontist due to the clinically appreciable characteristic appearance and confirmed by the various analyses devoted to these anomalies. 

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE

  Cracked teeth can be healed with modern techniques.
Gum disease can be prevented with proper brushing.
Dental implants integrate with the bone for a long-lasting solution.
Yellowed teeth can be brightened with professional whitening.
Dental X-rays reveal problems that are invisible to the naked eye.
Sensitive teeth benefit from specific toothpastes.
A diet low in sugar protects against cavities.
 

DIAGNOSIS OF ALVEOLAR AND BASAL ANOMALIES IN THE VERTICAL SENSE