s10-Microsurgery Flashcards
What is the rationale behind surgical retreatment in endodontics?
To address persistent infection or failure of non-surgical treatment by removing causative agents and restoring tissue health.
What are the key considerations before performing endodontic surgery?
- Patient medical status,
- psychological impact,
- local anatomic factors,
- professional judgment.
What are the main procedures involved in peri-radicular surgery?
Curettage, root-end resection, root-end cavity preparation, and root-end filling.
How does microsurgery differ from traditional endodontic surgery?
Microsurgery uses magnification, illumination, and micro-instruments for precision, reducing trauma and improving outcomes.
What is a common indication for endodontic surgery?
Failure of non-surgical retreatment after at least two attempts.
When is a biopsy necessary in endodontic surgery?
When a definitive diagnosis of peri-radicular pathosis is required.
What is the prevalence of periapical granuloma in endodontic cases?
0.73
What percentage of endodontic cases involve periapical abscesses?
0.12
How common are true cysts in endodontic cases?
0.09
What is the prevalence of pocket cysts in endodontic cases?
0.06
Why is indiscriminate surgery contraindicated in endodontics?
Surgery should not compensate for lack of skill in non-surgical treatment or be routine for every case with a lesion.
What is a contraindication related to a patient’s medical status?
Systemically compromised patients require physician consultation before surgery.
Why is psychological impact a consideration before endodontic surgery?
Patients should verbalize their fears and thoughts after being informed about the procedure.
What local anatomic factor contraindicates endodontic surgery?
Short root length or poor bony support.
What is a contraindication related to non-strategic teeth?
Teeth that are not essential for function or aesthetics should not undergo surgery.
What are the two types of surgical drainage in endodontics?
Incision & Drainage (I&D) and Cortical Trephination.
What is the purpose of incision and drainage in endodontic surgery?
To eliminate toxins and alleviate pain by releasing pus from an acute apical abscess.
What is a challenge of performing incision and drainage?
Difficulty obtaining adequate anesthesia due to inflammation and acidity in the area.
What is cortical trephination used for in endodontic surgery?
To drain pus and exudate trapped in cancellous bone behind the cortical plate.
What is the technique for cortical trephination?
Anesthesia, mini-vertical flap, bone removal, drainage, and suturing.
What is peri-radicular surgery?
Surgical procedures to address peri-radicular disease, including curettage and root-end management.
What is an indication for peri-radicular surgery?
Irretrievable root canal filling or procedural errors like instrument fragmentation.
What is the purpose of root-end resection in peri-radicular surgery?
To remove the untreated apical portion of the root and provide a flat surface for root-end filling.
How much of the root-end should be resected during apicoectomy?
At least 3 mm to reduce 98% of apical ramifications and 93% of lateral canals.
What is the recommended angle for root-end resection?
Zero bevel (90°) to minimize dentinal tubule exposure and improve sealing.
What is the aim of root-end cavity preparation?
To remove intracanal irritants and create a cavity for proper root-end filling.
What is the ideal depth for a root-end cavity preparation?
At least 3 mm along the long axis of the tooth.
What is an isthmus in endodontic surgery?
A narrow strip of tissue connecting two root canals, commonly found in maxillary molars.
What is the incidence of an isthmus in mesial roots of mandibular molars?
Over 80%.
What is the advantage of ultrasonic root-end preparation?
Superior operator control, cleaner cavities, and reduced risk of perforation.
What is corrective surgery in endodontics?
Surgery to repair defects in the coronal or middle third of the root, such as perforations.
What is a mechanical perforation repair?
Immediate sealing of mid-root or apical third perforations with materials like Super EBA.
What is resorptive perforation repair?
Repair of defects caused by internal or external resorption, often using calcium hydroxide.
What is root amputation?
Removal of a diseased root while preserving the remaining tooth structure.
What is hemi-sectioning?
Vertical division of a multi-rooted tooth to remove a pathologic root.
What is bi-cuspidization?
Dividing a molar crown into two halves to improve periodontal health and maintenance.
What anatomic structure is close to maxillary anterior roots?
The nasal floor.
Why is the labial cortical plate in the maxillary anterior region important?
It is thin and requires careful management to avoid root fenestration.
What is a concern in the maxillary posterior region during surgery?
Proximity of roots to the maxillary sinus, which can lead to sinus perforation.
What is the average distance between maxillary posterior roots and the sinus?
Less than 1 mm in some cases, especially in patients under 40 years old.
What is a key consideration for the palatal approach in endodontic surgery?
Avoiding the greater palatine vessels during flap design.
Why is the anterior palatine artery important in palatal root surgery?
It must be carefully managed to avoid severe bleeding; ligation may be required if severed.
What is a concern in the mandibular anterior region during surgery?
The reduced labio-lingual dimensions of alveolar bone increase the risk of lingual perforation.
What is a challenge in the mandibular posterior region during surgery?
The increased thickness of the buccal cortical plate makes osteotomy more difficult.
What is the average location of the mental foramen?
16 mm inferior to the CEJ of the second premolar (range: 8–21 mm).
What is the average vertical distance from the mandibular canal to the distal root apex of the second molar?
Approximately 3.5 mm.
What are the four pathways of blood supply to alveolar mucosa and gingiva?
Sub-epithelial capillaries, periosteal vascular network, intra-septal arteries, and periodontal plexus.
What is the purpose of a patient interview before endodontic surgery?
To inform the patient of benefits, risks, and alternative treatment options.
What pre-medications are commonly used before endodontic surgery?
NSAIDs, antibiotics, chlorhexidine gluconate, and conscious sedation.
What is the primary goal of incision and drainage (I&D)?
To eliminate toxins and alleviate pain by releasing pus from an acute apical abscess.
What is the best time to perform incision and drainage?
When the swelling is soft and fluctuant, indicating accumulated pus.
What is a challenge of obtaining anesthesia during I&D?
Increased acidity in inflamed tissues reduces anesthetic effectiveness.
What is the technique for incision and drainage?
Topical anesthesia, sweeping incision with a No. 11 scalpel, aspiration, and irrigation.
What is the purpose of hot mouthwash after I&D?
To speed up pus collection and fluctuation.
What is cortical trephination used for?
To drain pus and exudate trapped in cancellous bone behind the cortical plate.
What is the technique for cortical trephination?
Anesthesia, mini-vertical flap, bone removal, drainage, and suturing.
What is a T-drain, and when is it used?
A drain inserted to facilitate prolonged drainage in cases of extensive infection.
What is the advantage of a mini-vertical flap in cortical trephination?
It is easy to suture, heals faster, and causes less scarring.
What is a contraindication for a mini-vertical flap?
Large lesions or cases requiring expanded visibility.
What is the role of chlorhexidine gluconate in surgical drainage?
To reduce surface bacteria and prevent infection.
What is the purpose of soft tissue management in peri-radicular surgery?
To design and reflect a flap that provides access while preserving blood supply.
What is the most commonly used blade for endodontic flaps?
The #15C blade.
What is the key principle for vertical incisions in flap design?
The incision should not extend into the muco-buccal fold to avoid bleeding.
What is the advantage of a papillary-based incision?
It results in rapid, recession-free healing compared to complete papilla mobilization.
What are the types of muco-periosteal flaps?
Triangular, rectangular, trapezoidal, and horizontal flaps.
What is the advantage of a single vertical flap?
It eliminates the risk of horizontal incisions crossing osseous defects.
What is the disadvantage of a double vertical flap?
It is more difficult to suture and may cause gingival recession.
What is the purpose of tissue retraction in surgery?
To hold the reflected flap in position without crushing it.
What is the best method to locate the root apex during osteotomy?
Using a sterile ruler, radiographs, or CBCT to measure the root length.
What is the biological consideration during osteotomy?
Minimizing heat generation and preserving healthy hard tissue.
What is the ideal size of an osteotomy for faster healing?
3–4 mm, as smaller lesions heal faster (6.4 months for <5 mm lesions).
What is the purpose of curettage in peri-radicular surgery?
To remove all pathologic tissue and bone particles from the peri-radicular area.
What is the purpose of a biopsy in peri-radicular surgery?
To establish a definitive diagnosis of the lesion.
What is the role of hemostatic agents in surgery?
To minimize bleeding, enhance visibility, and ensure a clean environment for root-end filling.
What is the ideal root-end filling material?
MTA (Mineral Trioxide Aggregate) due to its biocompatibility and sealing ability.
What is the purpose of root-end filling?
To hermetically seal the resected root end and promote cementogenic repair.
What is the triad of microsurgery?
Magnification, illumination, and micro-instruments.
What is the advantage of using an operating microscope in endodontic surgery?
It allows precise identification of anatomical details and reduces occupational stress.
What is intentional replantation?
Extracting a tooth, performing root canal treatment, and replanting it in its socket.
What is the definition of osseo-integrated implants?
Direct structural and functional connection between living bone and a load-carrying implant.
Indications for microsurgery
- Failure of non-surgical retreatment.
- Failure of initial treatment.
- Biopsy requirement.
- Procedural errors.
- Anatomic variations.
