Periradicular Surgery (Replogle) Flashcards
What are 4 treatment modalities for apical periodontitis, especially persistent apical periodontitis?
- Non-surgical root canal therapy (NSRCT)
- Retreat (RETX)
- Microscopic Periapical Surgery (Apicoectomy)
- Extraction (EXT)
What is the highest success rate study for NSRCT (retained in the oral cavity for 8 years)?
97%
What is the diagnosis of a previously endo-treated tooth if the periodical radiolucency has not filled in with normal bone trabeculation in 6 months to 2 years, the average being 9 months?
Failing NSRCT
What is a major histologic difference in marginal periodontitis and apical periodontitis?
They have different bacteria
What is the diagnosis of a previously endo treated tooth that is symptomatic?
Failing NSRCT
What are the options for a failing NSRCT?
- RETX
- Apicoectomy
- EXT tooth and replace with FPD, RPD, or Implant
What should be done for a failing NSRCT: apicoectomy alone, or RETX then apicoectomy?
RETX apicoectomy
What is the success rate if only do an apicoectomy (microscopic periscopical surgery) alone on a failing NSRCT tooth?
59%
What is the success rate if you do a RETX followed by apicoectomy (microscopic periodical surgery)?
80%
Dr Replogle had a slide showing a NSRCT treated molar that turned out to have a missed 4th canal, she said that after the initial poor NSRCT, how long should it take for the periodical radiolucency (PARL) to reappear?
6 months - 2 years, but I have no idea where this comes from
What ist he treatment of choice if the tooth with failing NSRCT had its NSRCT done recently and properly, and there was immediate placement of a coronal restoration?
Can skip RETX and go straight to apicoectomy (note: this is the exception, not the rule)
What is the criteria for a properly done NSRCT?
All canals located, ideally irrigated, obturated
What are synonyms for apicoectomy?
- Microscopic periapical surgery
- Root end resection
- Microsurgical root end resection
What is the rule of thumb for planning treatment of a failing NSRCT?
Retreat prior to doing surgery ensures best success
What would be the treatment indication for an abutment tooth that has a long post, gutta percha extending out apical foramen, and the FPD has been recently placed on it and why?
Apicoectomy. Long post and core prevents RETC and do not want to mess up new FPD.
What is the purpose of periapical surgery?
Gain access to root apex and surrounding periodical tissues in order to remove uncleaned or unfilled tooth structure and place a biocompatible seal in the form of a root end filling
The removing of the uncleaned or unfilled tooth structure during periapical surgery is called what?
Root end resection
What is done with granulation tissue or cyst contents removed from the site during periapical surgery?
Submit for biopsy
What is the desired result for periapical surgery?
Formation of new cementum on the surgically exposed root surface and on the root end filling which is essential for regeneration of the periodontium (periodical surgery)
What is indicated if there is significant overextended obturating material with symptoms / lesions?
Endodontic surgery (periapical surgery)
What is indicated if a tooth has a long post or irretrievable separated instruments preventing a standard RETX?
Endodontic surgery (periapical surgery)
What is indicated if a tooth has non-negotiable ledges and canal blockages or transportation?
Endodontic surgery (periapical surgery)
What is indicated for a suspected root fracture?
Endodontic surgery (periapical surgery)
What is indicated for hard setting obturation material / cement that cannot be removed during pretreatment (e.g. obturation carrier)?
Endodontic surgery (periapical surgery)
Is endodontic surgery contraindicated in areas with close proximity to anatomic structures (e.g. IAN, mental foramen, maxillary sinus, nasal fossa)?
Yes
What are contraindications to endo surgery?
- Uncontrolled diabetes
- Blood disorders
- Immunocompromised
- Severe cardiovascular problems
- Long term bisphosphonate therapy
Should microsurgery be referred?
Yes. They have microscopes and special instruments.
Besides the ever-present Endo Microscope, what are some other microsurgery armamentaria?
- Diamond coated micromirrors
- Microblade
- Ultrasonic tips
- MIcrocondensers
- MTA delivery instruments
What is the first step in apical surgery?
Local anesthesia with 1:50,000 epinephrine
What is the purpose of the 1:50,000 eli?
Hemostasis
What is done after anesthesia is attained for endo surgery?
Incision and flap reflection
What is done after the flap has been reflected?
Access root apex
What is done after the root apex has been accessed?
Curette the diseased tissue
What is done after curetting the diseased tissue?
Root end resection and inspection under high magnification
What is done after the root end resection?
Retroprep of the root end
What is done after the retropre?
Retrofill the retroprepped root apex
What is done after the retrofit?
Reapproximate and suture flap, give post op instructions
What is one design of the flap for endo surgery?
Full mucoperiosteal intrasulcular flap with 1 or 2 releasing incisions
What is the second flap design for endo surgery?
Ochsenbein-Luebke Submarginal flap
What is an advantage of the submarginal Ochsenbein-Luebke flap design?
Results in recession free healing
What is a requirement for submarginal Ochsenbein-Luebke flap design?
Must have 2mm or retained attached gingiva
Would a submarginal Ochsenbein-Luebke flap design be indicated if there was a suspected fracture in the tooth and why?
No, because you cannot see the entire root. The full mucoperiosteal intrasulcular flap is indicated as it gives full root access
Can a semilunar (curve submarginal) flap design be used?
No
Vertical incisions of flap should be parallel to what?
Superperiosteal vessels
Is it permissible to cut across frenums or muscle attachments when designing a flap?
No
Can the incision for a flap be made over diseased or compromised bone?
No. Must be directly over healthy bone.
Can a flap incision be made over a bony prominence?
No
What is done with the papilla during flap design?
Either include or exclude, but do not dissect
What is the minimum amount of teeth either side of the tooth to be worked on to allow good surgical access?
At least one tooth either side of surgery tooth
What is always a concern when working around a flap?
Careful reflection and retraction to avoid crushing or tearing of tissue
How much root end is resected during endo surgery and why?
3mm. Will include most lateral canals and apical ramifications to eliminate most residual microorganisms
What is the minimal bevel desired for a root end resection?
0 to 10 degrees. Torabinejad says as close to 0 degrees as possible, but consider visualization and access.
What are reasons to bevel 0 to 10 degrees for apical resection?
- More likely to include all apical ramifications and lateral canals
- Less dentinal tubules exposed
- Less leakage
- Better force distribution to reduce fracture risk
What are the percent reduction for apical ramifications if you take away 3mm in apical resection?
98%
What are the percent reduction for lateral canals if you take away 3mm in apical resection?
93%
Why worry about getting the apical ramifications?
Becteria in apical ramifications may be the cause of persistent apical periodontitis
What are 6 retrofit (root end filling) materials?
- MTA
- Super-EBA
- IRM
- Amalgam
- Resin
- Gi / RMGI
Of the 6 retrofit materials listed above, which is the best?
MTA
What is a disadvantage of amalgam for retrofit?
- Poor sealing ability
2. Irritating to tissues
What are the 5 main constituents of Mineral Trioxide Aggregate (MTA)?
- Calcium Silicate
- Bismuth oxide
- Calcium carbonate
- Calcium sulfate
- Calcium aluminate
The hydration of MTA forms what?
Calcium oxide crystals
What is a diagnostic advantage of MTA over IRM or S-EBA?
More radiopaque
Do MTA, S-EBA, and IRM have equal sealing abilities?
Yes
What is the biocompatible phenomenon see with MTA for root resection?
- PDL fibers attach to it
2. Cellular cementum forms adjacent to it
This is a modified Zinc-Eugenol paste that has 37.5% eugenol and 62.5% ortho-ethoxy benzoic acid mixed into the 60% zinc oxide powder (it is not very radiopaque but it is not resorb able, seals well, and is easy to place)?
Super EBA
What is the success rate for microsurgery with ultrasonics?
91.5%
What is the success rate for endodontic microsurgery?
94%
Does endo microsurgery have to be confined to the root apex?
No. Dr Replogle’s case with cervical resorption filled with geristore and restored using microinstruments