Pathologies of immature permanent teeth
Pathologies of immature permanent teeth
1. Introduction
The immature permanent tooth is characterized by an apex that is not yet closed, but which remains susceptible to external aggression such as caries and dental trauma.
Our interventions on immature permanent teeth involve evolving structures and must allow for the most physiological dental and alveolar development possible.
2. Anatomy/physiology of the immature permanent tooth:
2.1. Anatomical and physiological characteristics:
The immature tooth is characterized by:
Lack of edification of the apical region:
- The apex appears wide open in a funnel or blunderbuss shape.
- The root canal is wide.
- The thin and fragile walls appear divergent, parallel or convergent, depending on the stage of root formation.
- The vestibulo-lingual diameter is always larger than the mesio-distal diameter.
- This highly vascularized tooth has significant cellular potential and actively participates in root formation.
Pathologies of immature permanent teeth
At the coronary level:
- The furrows are deep and cracked.
- The dental layer is thin and poorly mineralized.
- The tubules are widely open.
- The pulp volume is very important (the pulp morphology of DPI differs from that of adult teeth by its very important volume, by its richness of its vascularization, the pulp will itself model its future cavity by apposition of secondary dentin
2.2. Physiology of the development of PGD: Two phases can be distinguished in the development of PGD:
2.2.1. The active growth phase : lasts about a year and ends when the tooth reaches a functional occlusal position.
At this stage the apices are still wide open.
2.2.2.The maturation phase :
Lasts about 3 years and corresponds to the formation of the apical 1/3. It is carried out thanks to the radicular pulp and the periodontal connective tissue. It is characterized by:
- Completion of mineralization of primary dentin.
- The complete construction of the cementum envelope which leads to the macroscopic closure of the apex.
The formation of the surrounding alveolar bone from the internal cortex: the lamina dura.
3. Etiopathogenesis of the immature permanent tooth
3.1. dental caries
Caries, when affecting immature permanent teeth, must be diagnosed and treated as quickly as possible in order to preserve pulp vitality and thus allow the physiological formation of the tooth roots.
Complications of carious lesions can be pulpal (chronic, acute inflammation) and periodontal (chronic or acute periodontitis). Their development is faster in young permanent teeth, due to the immaturity of the tissues.
In cases of reversible pulp inflammation, preservation of tooth vitality is the primary objective. Treatment consists of removal of the carious lesion followed by capping of the pulp tissue using a biomaterial.
Risk factors
•The salivary concentration of defense factors (lysozyme, secretory IgA) is less important
•Saliva flow is weaker
•A decrease in the oral clearance of dietary sugars
3.1.1. Clinical forms
- Progressive fissure caries
- Initial caries (pre-carious leukoma)
3. 1.1.1 Progressive fissure caries:
• Etiology:
- Incomplete coalescence of enamel prisms at the bottom of the grooves
- the first permanent molars are not immediately in occlusion, so there is no self-cleaning and brushing is difficult
•Location : furrows, pits and cracks
- occlusal faces
- of the palatal surfaces of the maxillary molars
- of the vestibular surfaces of the mandibular molars.
• These anfractious grooves lead to dentin with widely open tubules.
• These are extensive caries in depth and width developing under the surface of the enamel
• Evolution very often occurs without painful clinical signs.
• Clinical and radiographic screening : small hole discovered during examination with the probe very often results in a very large area of unsupported enamel.
3.1.1.2. Initial caries (pre-carious leukoma)
•Etiology :
- Poor oral hygiene, high consumption of fermentable sugars, impaired salivary function, wearing of multi-bracket orthodontic appliances.
•Location:
- Vestibular surfaces of incisors and canines
- Vestibular necks of premolars and molars
•Clinical appearance : chalky or whitish spot
•Damage to the enamel with rapid extension to the surface
•If the enamel has a mineralization defect (coloration, matte appearance), multi-bracket treatments should be avoided.
3.2. Symptoms:
3.2.1. Enamel caries:
- Interrogation: Symptoms:
- No spontaneous pain
- Pain caused by cold
- Positive vitality test (cryospray)
- Cease with cessation of stimulation.
Pathologies of immature permanent teeth
3.2.2. Enamel/dentine caries:
- Examination:
- Symptoms
- No spontaneous pain
- Pain caused by sugar and cold that ceases when stimulation stops.
- Positive vitality test (cryospray, milling)
Pathologies of immature permanent teeth
3.2.3. Enamel/dentine caries reversible pulp involvement:
- Questioning: symptoms
- Rare spontaneous daytime or nighttime pains that may last
- Yield to painkillers, not very intense
- Pain caused during and after meals (food compression).
- Pains provoked (cold and sugar) slightly prolonged after stopping the stimulation
- Positive vitality test (cryospray, milling)
Specific physiological characteristics:
- Pulp defense potential
- Open apex
- Reversible pulp involvement
Therapeutics
Preservatives of pulp vitality:
Apexogenesis: root growth and physiological apical closure of an immature permanent tooth
Total or partial pulp vitality:
- Indirect pulp capping
- Direct pulp capping
- Partial vital pulpotomy
3.2.4. Enamel/dentine caries irreversible pulp involvement:
- Questioning: symptoms
- Rare spontaneous prolonged daytime or nighttime pain, rarely insomnia
- Yield to painkillers, not very intense
- Pain caused during and after meals (food compression).
- Prolonged induced pain (cold and sugar) after stopping stimulation
- Positive vitality test (cryospray, milling)
3.2.5. Pulp necrosis:
- Questioning: symptoms
- prolonged, dull, diffuse spontaneous daytime or nighttime pain.
- Yield to painkillers
- Pain caused by chewing if
- Periodontal involvement (apical lesion)
- Pain caused by heat, cold tends to calm the pain.
- Negative vitality test.
- Treatment:
- Apexification (Ca(OH)2)
- No root growth
- Apical barrier of osteo-cement by periapical cells
3.2.6. Complications of necrosis:
- Examination:
- Symptoms of necrosis
- Clinical examination:
- Cellulite, lymphadenopathy
- Canal odor of anaerobic bacteria
- X-ray examination +++
- Treatment: apexification
- Appropriate antibiotic therapy
3.3. Trauma
- The maxillary incisors are most often involved due to the frequency of proalveolism. These are accidents related to sports activities in children aged 8 to 11, most often boys.
- We distinguish:
•Coronary fractures and their degree of exposure
•Corono-radicular fractures (enamel, dentin, pulp)
•Root fractures
•Concussions/subluxations
• Lateral dislocations
•Intrusions
•Extrusions
•Evictions
Pathologies of immature permanent teeth
Pathologies of immature permanent teeth
Pathologies of immature permanent teeth
3.4. Incidence of caries and trauma on pulp tissue:
- The dentinal tubules exposed by caries are an easy access route for pulp irritants , both bacteria and chemical, thermal or mechanical agents, these iatrogenic factors trigger an inflammatory reaction.
- In the case of a coronal fracture, without pulp exposure, the process is similar; after the break, it is a little different: there may be immediate inflammation but most often, the young pulp protects itself by forming a “covering” epithelial tissue (reversible pulpitis).
- Root fractures are rare, with immature teeth most often being expelled following trauma.
3.5. Impact on root formation:
- Inflammation inhibits root growth, irritated cells and microorganisms produce numerous enzymes that act and modify the behavior of cells in surrounding tissues. For example, collagenases will remove the matrix support of dentin.
- Of course, if the necrosis becomes total, there are no more odontoblasts, and therefore no more possibility of dentin development!
Pathologies of immature permanent teeth
Sensitive teeth react to hot, cold or sweet.
Sensitive teeth react to hot, cold or sweet.
Ceramic crowns perfectly imitate the appearance of natural teeth.
Regular dental care reduces the risk of serious problems.
Impacted teeth can cause pain and require intervention.
Antiseptic mouthwashes help reduce plaque.
Fractured teeth can be repaired with modern techniques.
A balanced diet promotes healthy teeth and gums.