Treatment of dental agenesis

Treatment of dental agenesis

The treatment of dental agenesis, which affects approximately 5% of the population, requires the practitioner to make a difficult choice between a closure solution, mainly orthodontic, and a solution of replacing the missing tooth with a prosthesis requiring multidisciplinary treatment.

Any solution is only a compromise and the selection criteria evolve according to technical advances in both prosthetics and orthodontics.

1. General:
2. Definition :​

Dental agenesis is a numerical anomaly corresponding to the absence of a dental unit, in relation to the absence of the corresponding germ .

• It is most often a permanent tooth.
• This anomaly can affect one or more teeth, and be unilateral or bilateral.

2. Frequency :
   • According to Polder et al., agenesis is more common in Australia and Europe than in the United States.

• They affect women more than men (1.37 women for 1 man) and mainly concern :
• the second mandibular premolars (41% of wisdom tooth agenesis excluded);
• maxillary lateral incisors (22.9%);
• the second maxillary premolars (21.2%). Agenesis can be uni- or bilateral.

That of the lateral incisor is most often bilateral.

• In the majority of cases (83%), agenesis affects one or two teeth, but some patients present with multiple agenesis which, in 2.6% of cases of agenesis, affects
• six or more teeth.

3. Diagnosis:

Persistence of the temporary tooth , without malposition of the neighboring teeth, the homologous tooth being present on the arch.

Absence of the permanent tooth after removal of the temporary tooth.

Radiologically: the absence of the germ , after its normal date of appearance.

• progressive or non-progressive elimination of the temporary upper lateral incisors by the germs of the adult canines.

NB: do not confuse agenesis with delayed eruption or formation of the germ (for lower second premolars and wisdom teeth).

2. Agenesis of the lateral incisor :​​​

It is agenesis that poses the most delicate problem because of the location of the lateral incisor in the arch and its functional and aesthetic role.

The practitioner must choose between:

• A so – called substitution solution by closing the agenesis space , the canine then playing the role of lateral incisor and the first premolar that of canine ;
• a replacement solution with a prosthetic element .

1. selection criteria:

• The coronal morphology of the upper canines and incisors;
• The color of the canines: very yellow canine
• The initial position of the canine germs: mesial or in the usual position;
• Initial molar relationships: maintain initial Class II or Class I relationships;
• Bone base shift;
• Convexity of the profile
• Facial typology:
• Initial incisor overbite: difficulty in prosthetic production;
• Generalized microdontia
• Occlusal function : in the event of temporomandibular dysfunction , the canines must be placed in class I;
• Initial periodontal conditions: height of attached gingiva, thickness of external cortex,
• socio-economic considerations.

2. orthodontic therapy :
   1. Conservation or augmentation of spaces with prosthetic replacement :

1.  Early treatment : look for clear Class I molar relationships (FEB on bands) .
2.  Late treatment : repositioning of the canines in class I and closure of the interincisal diastema (multi-attachment device).

Different prosthetic solutions:

• We will always seek the least damaging solution for the patient’s dental system while respecting the aesthetic and

functional. Implant-supported single crowns or bonded bridges.

C) Indications:

• skeletal class III cases
• Class II cases due to mandibular retrognathia where it is preferable to maintain the space and perform an orthopedic correction or

surgical sagittal shift, in order to avoid a receding profile.

• patients with a long nose or an open nasolabial angle.
• Concave profile ;
• End- to- end incisor occlusions ,
• dentomaxillary disharmonies with microdontia and diastemas;
• Absence of another tooth in the same area of ​​the arch
• Treatments requiring maxillary expansion .

2. Closing spaces: Alternative solution
3.  Early treatment : promote mesial development of canines and first permanent molars
   • Early extraction of temporary incisors and temporary canines
   • Extraction, after development of the 14th and 24th second molars

temporary or grinding of the proximal, distal and mesial faces of these teeth.

• B) Late processing:

Coronoplasty (in one or more sessions) :

• — orthodontic treatment: multi-attachment device essential , Delaire mask possibly (trend towards class III);
• — after treatment:

. Aesthetic finish: reconstruction of the angles using a composite.

. Occlusal rebalancing: grinding of the palatal cusp of the first upper premolar.

C. Indications:

• Excessive dentomaxillary disharmonies;
• Biproalveoli;
• Skeletal Class II due to maxillary prognathism;
• Convex profiles, with a closed nasolabial angle;
• Hyper mandibular divergence;
• Significant deviations of the maxillary midline, in cases of unilateral agenesis.

3. Agenesis of the second mandibular molar:

This is the most common agenesis, except for wisdom teeth. As in the case of lateral incisor agenesis, the practitioner is faced with the choice of closing or opening the space or maintaining it for possible prosthetic restoration.

1. selection criteria:

• presence or absence of dento-maxillary disharmony .
• Class II requiring occlusal adjustment with extractions.
• Convexity of the profile,
• Facial typology
• Agenesis of maxillary premolars
• Dental malformations of other teeth.

2. therapeutic:
3. Closure of the agenesis space:
   • It is similar to treatment with premolar extractions.
   • solidarity of the previous sector;
   • mesialization of the first then the second molar
   • use of extraoral posteroanterior traction devices or class II TIMs;
   • use of miniscrews as direct anchoring.
   • occlusal equilibration must be performed to achieve Class III occlusion .

Indications:

• DDM imposing extractions;
• Mandibular proalveolism,
• Class II requiring occlusal adjustment with extractions
• Convex profile;
• Hyperdivergent type
• Absence of maxillary premolars;

2. Maintenance of the temporary tooth and prosthetic solution:
   • The long-term solution is to have an implant. Indeed, the

Traditional bridges are too damaging to adjacent teeth and bonded bridges do not have the same reliability as on the anterior sector.

• The retention of the temporary tooth maintains the alveolar bone at the future implantation site and acts as a space maintainer. It is therefore advisable to keep it until the implant is placed.

Indications:

• Absence of DDM
• Class II with mandibular responsibility
• Concave profile;
• Hypodivergent type.

4. Multiple agenesis:

The consequences are more severe and the therapy is most often implanted at the end of growth.

Temporary teeth are kept as long as possible to maintain the alveolar bone. However, the aesthetic damage can be significant, requiring temporary prosthetic devices (veneers or crowns on the anterior temporary teeth, removable prosthesis, etc.) to give the young patient an acceptable smile during their adolescence.

Conclusion :

• The treatment of dental agenesis requires a well-developed diagnostic approach with an in-depth study of the criteria for therapeutic choice.
• In certain cases, care requires multidisciplinary work.
• In replacement solutions, definitive prosthetic restorations can only be placed after growth has finished.

Treatment of dental agenesis

  Wisdom teeth can cause pain if they erupt crooked.
Ceramic crowns offer a natural appearance and great strength.
Bleeding gums when brushing may indicate gingivitis.
Short orthodontic treatments quickly correct minor misalignments.
Composite dental fillings are discreet and long-lasting.
Interdental brushes are essential for cleaning narrow spaces.
A vitamin-rich diet strengthens teeth and gums.

Treatment of dental agenesis