Single tooth efficiency model (STEM)
- Local conditions; patient in need of single-tooth extraction because of trauma/fracture, external/internal root resorption, advanced caries/periodontal disease.
- Consider patient´s general/local symptoms, clinical and radiographic signs of infection, condition of adjacent teeth, patient´s desires/expectations.
- Extraction resulting in intact alveolar bone walls, elimination of infection, and provided that standard prerequisites are at hand for implant placement, consider STEM, i.e. extraction with immediate implant placement and immediate loading.
Special attention should be paid on oral hygiene, health condition of adjacent teeth (active caries lesions, former restorative treatment, periodontal status) and other oral tissues (remaining alveolar bone volume, pathology within alveolar bone, mucosa condition).
What are the expectations from the patient?
Consider age of the patient and the best timing to perform the procedure. A majority of trauma cases are adolescents, not fully grown up and not with stable occlusion. Decide treatment strategies prior to permanent treatment.
Provided that standard requirements for single implant treatment are fulfilled, i.e. sufficient alveolar bone dimensions, any infection present may be eliminated during the procedure, adjacent teeth in good condition, completed growth of the jaw, etc, STEM may be suggested. STEM implies facilitated and faster treatment with one surgery only:
- Extraction aims at jaw bone preservation (Figures 1-5)
- Careful inspection of alveolus, eliminate granulation tissue as sign of infection
- Extend site preparation apically of alveolus for primary implant stability
- Aim at implant insertion torque ≥30 Ncm or resonance frequency value ≥ 60 ISQ (implant stability quotient) for one-stage surgery
- Fill any gap between implant periphery and bone wall of the alveolus (Figures 6,7). Autogenous bone /bovine particles/bone substitute materials may be used
- Connect abutment and wound closure. Deliver a provisional crown, adjusted out of occlusion (Figures 8-11)
Figure 2 Figure 3 Figure 4
Figures 1-4: Tooth 21 (#9 UNIV) presenting with external/internal root resorption (arrow). Careful extraction with periotome instrument, aiming for bone preservation.
Figure 5 Figure 6 Figure 7 Figure 8
Figures 5-8: Intact bone walls, immediate implant placement, discrepancy between former root size and implant diameter, abutment placed to receive immediate provisional crown
Figure 9 Figure 10 Figure 11
Figures 9-11: After extraction of tooth 41 (#25 UNIV), placement of implant/abutment and an immediate provisional crown (out of occlusion)