ORAL IMPLANTOLOGY
Figure 2 Decision-making for endodontic considerations
(7). The crown to root ratio achieved after these
procedures will affect tooth mobility and its
susceptibility to fracture (19). A crown to root ratio
of 1:2 and 1:1 have been suggested as appropriate
proportions in different clinical scenarios (20) but
a ratio of 1:2 is rarely encountered. As there is
no consensus or well-designed evidence-based
studies analyzing the influence of crown to root
ratio on teeth, it is believed that a crown to root
ratio of 1:1 or greater is preferred. If the final
crown to root ratio is less than 1:1, the tooth has
an unfavorable long-term prognosis and hence
extraction is recommended.
When a tooth has a questionable periodontal
prognosis, certain local and/or systemic factor/s
that contribute to the disease may or may
be controlled. During initial phase therapy,
mechanical debridement with or without
chemotherapeutics will be performed to remove or
control the etiological and/or contributory factors.
If periodontal treatment is successful, restorative
treatment will be considered. Conversely, if
periodontal treatment is not successful, extraction
of the tooth is considered. It is suggested that a tooth
with unfavorable prognosis, have uncontrollable
etiological or contributory factors resulting in
progression of periodontal breakdown. In this
situation, extraction is usually recommended.
For patients with high or unrealistic esthetic
demands, retaining a restorable endodontically
involved tooth with a questionable or unfavorable
periodontal prognosis via restorative treatment
may be a preferred option. This is because soft
and hard tissue remodeling after removal of
a periodontally involved tooth may result in a
residual ridge that has horizontal and vertical
deficiencies. Recreation of the lost tissue to the
58
pristine state for an implant restoration may be
technically challenging. As such, performing
endodontic treatment may be a better alternative.
Endodontic therapy has been shown to be more
cost effective when compared to tooth extraction
and replacement with an implant supported
prosthesis (21). However, 10% of teeth with
residual periapical lesions after conventional
endodontic therapy often require additional
surgical intervention (22). Implants too require
secondary interventions (23). Therefore, it is on the
clinician to provide the patient with information
on the risks, benefits and cost of each treatment
option before coming to a definitive restorative
plan.
Decision-making for endodontic considerations
(Fig. 2)
This decision tree was developed by considering
the following factors: history of endodontic
treatment, presence of periapical lesion and any
active signs and symptoms e.g. tenderness to
percussion, periapical abscess, and discharging
sinus tract. It serves as a reference for clinicians
managing endodontically involved teeth.
- No previous endodontic treatment
A restorable non-vital tooth with no history of
endodontic treatment could present with active
signs and symptoms e.g. periapical radiolucency,
tenderness to percussion, pain on chewing,
discharging sinus tract etc. In th