Periapical disease
The details of the various periapical conditions, their manifestation and diagnosis and the management and prognosis are discussed elaborately through simple question and answers in this section.
1. What are the three basic principles that decide the success or failure of endodontics?
• Complete cleansing and shaping of the canal • Completely sterile canal • Complete three dimensional filling of the root canal system.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1; 162
2. The presence of fistula is seen as a favorable sign in endodontics. Why?
The fistula provides a means of continuous drainage of the lesion which prevents sudden reactivation, either spontaneous or as a result of the operator’s intervention. So it is considered as a favorable sign in endodontics and it can even be created in some cases, if there is none.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1; 164
3. How are the fistulae treated during endodontic therapy?
The fistulae require simply an identification of the diseased tooth and cleaning and shaping of that tooth. Surgical removal of the tract itself is not recommended. The track heals by itself after appropriate endodontic therapy.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;167
4. How is the diseased tooth or the origin of the fistula identified in endodontic diagnosis?
The opening of the fistula may be found on the mucosa overlying the diseased tooth or it may be at a distance from the diseased tooth also. By inserting a GP thro the mucosal opening, the fistulous tract is opacified and this clearly demonstrates the diseased tooth or root.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;164
5. How is the fistula due to a periodontal lesion differentiated from the one of endo origin?
Sometimes, the fistula may run in the space of the periodontal ligament of the same tooth or the adjacent tooth simulating a lesion of periodontal origin. Pulp tests are usually performed on the crown of the tooth indicated by the GP inserted thro the fistula and a negative pulp response on that tooth tells that the lesion is of endodontic origin. Also when the lesion heals after about one week of cleaning and shaping of the canals of the concerned tooth, without the use of any medicaments within the canal, clearly indicates the endodontic origin of the fistula.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;164
6. What is a granuloma?
Chronic apical periodontitis is referred as granuloma which varies in size from a few mms to 1 cm or more and separated from the surrounding bone by a cleavage plane. Histologically it consists of inflammatory granulation tissue with capillaries, fibroblasts and connective tissue fibres. It arises in response to infection or inflammation of the periapical tissue caused by pulp necrosis.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;171,172
7. What are the four zones histologically in a granuloma?
Zones of necrosis/ infection, zone of contamination, zone of irritation and zone of stimulation.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;174
8. How does a granuloma appear radiographically?
Radiographically, a granuloma appears radiolucent and an incidental finding in routine radiographic checkups. The size and definition varies corresponding to the various portals of exit of the root canal system at the apex, on the side of the root or at the level of the furcation.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;175
9. How does a granuloma heal?
The infected canal contents are removed, the canal disinfected and all the portals of exit are sealed. Histologically, healing starts at the periphery of the lesion where reparative cells are more. The inflammatory cells disappear, the granulation tissue changes to non inflammatory granulation tissue. The osteoblasts which are morein the periphery forms a bony matrix which mineralizes and matures. Cementum forms in the areas of resorption of cementum and dentin. The periodontal ligament is the last structure to be restored to its normal architecture.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;175,176
10. How does a periapical cyst form?
The infected canal contents are removed, the canal disinfected and all the portals of exit are sealed. Under irritation around the apex, the continued growth of the epithelium with an increase in the size of the lesion occurs. The distance between the central cells of the lesion and the nutritive source also increases. The most internal cells start dying and their degenerative products attract fluid by simple osmosis and the size of the lesion increases forming a cyst.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;176
11. Histologically, how do a granuloma and a cyst differ from each other?
Histologically, the cysts resemble granulomas except the presence of a central cavity filled with fluids and semisolid materials and lined with a flat multilayered epithelium. The connective tissue surrounding the epithelium is similar to that in granuloma.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;177
12. How does a peripaical cyst manifest clinically?
They are usually asymptomatic. They may present as swelling and the pressure may cause loosening of the diseased or adjacent tooth. Untreated cysts may expand the maxillary or mandibular bone also. The apices of the nearby teeth may show external resorption if the size of the cyst is large.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;177
13. How does a radiograph assist in diagnosing a periapical cyst?
It is not possible to differentiate a cyst from a granuloma radiographically. Negative response to pulp tests help to confirm the diseased tooth. Radiographically, the cyst is usually a round, sharply demarcated radioluscency 1 cm or greater in size. Whereas the granuloma is usually smaller and less well defined radioluscency. Histological correlation is a must to arrive at a definitive diagnosis.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;177
14. What is a phoenix abscess?
It is an acute inflammatory reaction that establishes in a pre existing chronic lesion, granuloma or a cyst. The symptoms are similar to those of acute alveolar abscess except that radiologically, phoenix abscess has a clear radioluscency.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;184
15. What are the probable causes for the occurrence of phoenix abscess?
The mechanical irritation caused by over instrumentation, the infected material unintentionally being forced beyond the apex, incomplete cleaning and shaping with partial removal of necrotic debris are the probable causes for phoenix abscess.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;184
16. How do bacterial endotoxins play a role in causing sudden flare ups?
Certain intracanal medicaments like paramonochlorophenol, a phenolic compound, may extract endotoxins from bacteria. If cleaning is not complete and some necrotic material remains within the canal, the medication may provoke bacteriolysis. This sudden liberation of endotoxins from the bacterial cell wall cause sudden flare of acute symptoms.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;184
17. Why do sudden flare ups not occurring in cases with fistula?
The fistula provides a means of spontaneous drainage for the pus which would otherwise provoke an acute flare up. So it is considered as a favorable sign in endodontics.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;184,185
18. What causes acute apical periodontitis in a vital tooth?
In vital teeth, acute apical periodontitis occurs due to occlusal trauma from a recent restoration that extends beyond the occlusal plane or by chronic bruxism, extension of pulpal disease into the periapical tissues with the tooth still responding to thermal tests.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
19. How does acute apical periodontitis manifest clinically and radiologically?
Radiologically there are no periapical changes and there may be slight widening of the periodontal ligament and clinically, there is pain on percussion.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
20. What causes acute apical periodontitis in a necrotic tooth?
In necrotic teeth, it arises spontaneously from the diffusion of bacteria and toxins present in the root canal throughout the periodontium. It can arise iatrogenically due to over instrumentation, spread of infected material beyond the apical foramen or by overmedication.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
21. What are the symptoms of acute apical periodontitis?
Pain on percussion,sometimes on palpation. The tooth is well identified by the patient since the periodontal ligament is well innervated by proprioceptive nerve endings. The tooth may slightly extrude from the alveolus due to the accumulation of exudates between the fibers of the ligament.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
22. What are the important points to be kept in mind while treating acute apical periodontitis?
Determination of the cause and elimination of the same is the first point to be remembered. Traumatic occlusion should be adjusted. Tooth left open to allow drainage of the exudate for 30-45 mins. The working length and the apical patency are rechecked, prolonged irrigation with sodium hypochlorite is performed which will osmotically extract fluid from the periodontal ligament. After elimination of the cause, the tooth need not be left open. During treatment, the tooth should be relieved out of occlusion.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
23. What does acute alveolar abscess indicate?
Acute alveolar abscess represents the advanced stage of acute apical periodontitis arising from pulp necrosis that indicates the collection of pus at the level of the alveolar bone surrounding the apex of the tooth whose pulp has become necrotic.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
24. Why does intense throbbing pain and mobility occur in acute alveolar abscess?
The intense throbbing pain is due to increasing pressure from the accumulation of exudates in the surrounding tissues. Mobility is because of the strong pressure on the fibres of the periodontal ligament which are literally upside down or distended.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;186
25. Which is the start of the fistulous chronic apical periodontitis?
The exudate that is collected in the tissues surrounding the apex, causes erosion of the bony cortical plate and detachment of the periosteum and collection of pus in the surrounding soft tissues which become distended. If left untreated, the pus perforates the oral mucosa or the skin, creating a fistulous opening.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;186
26. What is the role of radiographs in diagnosing acute alveolar abscess?
Radiographs are usually of little help in arriving at a diagnosis since the apical zone is usually normal or sometimes show a slight widening of the periodontal ligament. Since it is a recent lesion and confined only to the cancellous bone, it is not visible radiographically. If there is a sharp radioluscency in the x ray, it represents a phoenix abscess which is an acute exacerbation of chronic apical periodontitis.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;186
27. How is acute alveolar abscess and acute periodontal abscess differentiated?
In a lesion of periodontal origin, the tooth has a vital pulp and responds positively to all pulp tests. Also there should be a pocket through which there is a pus discharge after probing. But this drainage can also occur in acute alveolar abscess, when the pus drains through the fibers of the periodontal ligament. In that case it is called a fistula and not a pocket. Also the swelling in acute periodontal abscess is more circumscribed and more coronal whereas the swelling in acute alveolar abscess is due to the infection arising at the apex of the tooth and it is more apical and diffuse.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;186
28. Why is pus drainage in acute alveolar abscess done without anesthesia?
This is because, • The inflammatory process generates an acidic environment and anesthesia would not be significantly effective. • In anesthesia is given, the relief of pain after the drainage of pus may not be experienced by the patient. • Anesthesia masks the results of cavity test to determine pulp vitality. • And since the pulp is necrotic, anesthesia is useless.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;187
29. How the pus is usually drained in acute alveolar abscess?
The natural way of draining the pus is through the root canals. Creating an access cavity leads to spontaneous drainage of pus first and then the hemorrhagic exudate. Slight manual pressure can be applied on the swelling to express the pus. If the pus doesn’t drain spontaneously, an endodontic instrument can voluntarily be pushed beyond the apex to express the pus. This is the only condition where the instrument can be taken beyond the apex.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;187
30. How the pus is drained when the collection is too far from the apex or when there is a post in the root?
An incision is made with BP# 11 blade at the lowest point of collection into which it is slowly pushed until it touches the bone. The procedure is very painful and it is necessary to use anesthesia.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;187
31. While draining the abscess with an incision, why should the anesthetic needle not penetrate the purulent collection?
The anesthetic needle should not penetrate the purulent collection because this would increase the pressure within the collection and cause the pus to extend into the nearby tissues. The patient would experience more pain than the anesthetic effect. So it is introduced tangentially to the mucosa and should be visible through the tissues and injected slowly.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;188
32. Why hot salt water rinses are advised for drainage of pus?
Hot salt water rinses are advised until the pain is completely resolved since this hypertonic solution will penetrate the root canals better and further drainage is facilitated by extraction of fluids by osmosis.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;190
33. Why is a three dimensional obturation essential?
After obturation of a canal three dimensionally, any remaining micro organisms in the canal become non viable within 5 days after RCT. So the obturation should extend till the apical foramen without leaving any portion unfilled or unsealed. These unfilled portions will then give space and food for the trapped bacteria, causing failure of the root canal treatment.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;163
34. What is pathogenesis of chronic apical periodontitis?
Once the pulp tissue has become necrotic, products of cellular degeneration, Bacterial toxins and bacteria themselves within the canal spread through the apical foramen or the lateral foramina into the surrounding periradicular tissue. A slow inflammatory process begins within the tissues of the PDL and may manifest as widening of PDL or granuloma or cyst.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;164
35. When can a fistula be confused for a lesion of periodontal origin?
Sometimes, the fistula may run in the space of the PDL of the same tooth or that of the adjacent healthy tooth giving rise to symptoms similar to a lesion of periodontal origin. Correct diagnosis is made by negative pulp tests performed on the crown of the tooth and by GP cone inserted into the fistula.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;164
36. How is the diagnosis of a fistulous lesion of endodontic origin confirmed?
When the fistula heals after cleaning and shaping of the root canals in about 1 week, without using any medication within the canals, it is confirmative that the diagnosis was correct and suggests that the prognosis is also favorable.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;164
37. What is the differential diagnosis of a fistula of cutaneous origin?
Localized skin infections, traumatic lesions, neoplastic lesions, osteomyelitis, tuberculosis and actinomycosis.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;170
38. Why is a granuloma easily removed together with the root to which it is attached, while extraction?
The granuloma is covered by a capsule that forms at the level of the PDL due to cohesion of the tissues within the PDL and the intertrabecular soft tissue of the adjacent bone. The bony insertions of the fibers of the PDL become disorganized and dysfunctional while they are still attached to the radicular cementum. So while extraction, the granuloma is easily removed with the tooth.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;174
39. What is external inflammatory resorption?
When the irritants are removed from the root canal, the lesion will persist chronically with indefinite continuation of destructive and reparative processes. The bony trabaculae as well as the radicular cementum and the apical dentin get resorbed. This is called external inflammatory resorption that stops with the removal of the irritants.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;175
40. What are the sequelae of an untreated cyst?
An untreated cyst may expand at the expense of the mandibular or the maxillary bone and may involve the apices of the nearby teeth also causing resorption of the roots, but their vitality is preserved.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;177
41. What are the other radioluscencies that resemble odontogenic cysts?
Lateral periodontal cysts, incisive canals cyst, nasopalatine duct cyst, traumatic cyst and keratocyst.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;178
42. What is the treatment of choice for periapical cysts?
The treatment of choice is endodontic therapy of the diseased necrotic tooth, followed by periodic checkups and radiographs. Surgical treatment is indicated only when the traditional non surgical therapy fails.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;182
43. How does a non surgical therapy for a cyst fail?
Failure to achieve complete drying of the canal, which is essential for a good apical seal, may be a reason for the non surgical therapy to fail. Calcium hydroxide placed as intracanal medicament may stimulate the healing mechanism and dry canal can be obtained easily.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;182
44. How does a cyst heal following non surgical therapy?
Following non surgical therapy, the cyst heals due to spontaneous disintegration of its walls that occurs after elimination of the irritants within the root canal. Also drainage of the cystic fluid reduces the internal pressure which favors healing. The most modern theory of healing is once the irritant stimulus is removed; the epithelial cells that have proliferated to become a foreign tissue are destroyed and removed by the immune system.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;182,183
45. Why prolonged irrigation with sodium hypochlorite is performed in treating AAP?
Sodium hypochlorite, by its hypertonicity, will osmotically extract fluid from the surrounding tissues, particularly the PDL which is the site of inflammation.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
46. Why is acute alveolar abscess represented as an advanced stage of AAP?
Pulp necrosis that produces AAP may cause the infection to extend to the periradicular tissues through the apical foramina. So acute alveolar abscess is considered as an advanced stage of AAP.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
47. Why is pain not radiating in acute alveolar abscess?
There is gradual accumulation of exudates in the pdl space of the diseased tooth, which is rich in proprioceptive nerve endings. This makes the pain to be localized to that tooth.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;186
48. How is acute alveolar abscess diagnosed clinically?
The diseased tooth id localized since it is painful to percussion and palpation and there is an increased mobility. When it crosses the cortical bone and the periosteum, the purulent collection becomes circumscribed and fluctulant. Pulp vitality tests are negative and all these help to diagnose acute alveolar abscess clinically.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;186
49. Why does an asymptomatic chronic lesion suddenly exacerbate?
An asymptomatic chronic lesion suddenly exacerbates either spontaneously or following endodontic procedure because of the failure of the organisms’ defenses against the bacteria coming from the root canal system. The equilibrium is disturbed and an acute exacerbation occurs.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;184
50. What is the prognosis of a tooth with acute alveolar abscess following endodontic therapy?
The prognosis is excellent; the bony destruction heals completely in contrast to the bony destruction of periodontal origin. The PDL fibers are not destroyed; they are only distended or disordered. So when the acute symptoms subside, the tooth becomes firm in its socket.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;190
51. How can a secondary periodontal lesion occur following an untreated endodontic lesion?
In an endodontic lesion that has drained spontaneously through the fibres of the PDL and the gingival sulcus, if not treated for a long time there may be bacterial plaque accumulation apically along the fistulous tract and the epithelial and the epithelial attachment migrates apically. A true pocket forms and results in a secondary periodontal lesion.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;190
52. When is a tooth considered to be craked?
A tooth is considered to be cracked when the potential segments of the fracture are held intact by a portion of the tooth through which the fracture has not yet extended.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;191
53. What are the possible reasons for a mandibular molar to crack commonly?
Teeth functioning in cusp – fossa relationship have structural fatigue especially in the lower teeth because they lack the transverse ridge that protects the upper molars. Also according to the lever principle, an exerted force is greatest close to the fulcrum and so there is a higher incidence of cracks in the second molars when compared to the first.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;192,193
54. How does a cracked tooth manifest clinically? ( OR) What are the symptoms of a cracked tooth?
A tooth with a crack involving only the enamel has no outward symptoms. A crack that involves the dentin may produce sensitivity to heat and cold that is difficult to be localized. There may also be pain while chewing certain food on the affected side. These symptoms may persist for a long period of time without being diagnosed and when it is diagnosed, it resembles the symptoms of an endodontic problem.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;194
55. What are the clinical findings that co exist with a cracked tooth?
Some of the most prevalent findings clinically are heavily developed masticatory musculature, wear facets in molars and premolars, big cusps accompanied by deep grooves and fossae and stains in the grooves and the fossae.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;196
56. Which tooth demonstrates the highest percentage of cracking?
Mandibular second molars demonstrate the highest no. of cracking or incomplete crown – root fracture.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;196
57. How is the tooth suspected to have a crack diagnosed clinically?
If a tooth is suspected to have a crack, all the existing restorations are removed. A thorough examination of the proximal walls and the floor of the cavity is done and checked for craze lines because even in the absence of symptoms, craze line is an alert for future problems. Duplication of patient’s symptoms by applying pressure on the tooth with a wet cotton roll or orange wood sticks produces pain that helps for diagnosis.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;197
58. What is a tooth slooth?
Tooth slooth is a recently invented device for effectively diagnosing a cracked tooth which consists of plastic handle that is tied to a pyramidal shaped block with a small concavity. Patients are asked to bite on the concavity placed on the cusps. This action is obtained till a response is obtained.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;197
59. How tooth sooth is better than a wooden stick or striking with a mouth mirror handle?
Striking the teeth with a mouth mirror handle or the patient biting on a wooden stick is dangerous because the forces are not evenly distributed on the occlusal surfaces of these maneuvers. They may not elicit any symptoms or they may worsen the condition causing further fragmentation. Biting on a moist cotton roll, one tooth at a time is also a safe method.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;197
60. How does pain occur when the patient bites on a cracked tooth?
When the patient bites on a cracked tooth, the pressure will provoke a small separation of the fragments. This will lead to a stimulation of the pulp, causing sharp pain.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;198
61. How does Trans illumination help to diagnose crack in a tooth?
Trans illumination with a fiber optic light placed on the buccal or lingual surface of the tooth will stop the light at the fracture line.Thus it helps for the diagnosis of the fracture tooth.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;198
62. How are coloring agents used for diagnosing a cracked tooth?
Different colouring agents like fucsin, methylene blue, gentian violet or caries detector dyes can be used to uncover the fractures.The colouring agent is left in the tooth and covered by sedative cement for 2 days for best results.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;198
63. What are the four different categories of fracture according to Williams?
Class I: Incomplete, vertical fracture of enamel and dentin that do not affect the pulp. Class II: incomplete vertical fracture that affects the pulp Class III: Incomplete vertical fracture that crosses the attachment apparatus. Class IV: complete fracture that divides the tooth.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;199
64. How is a fracture of enamel and dentin without pulp involvement treated?
After diagnosing the affected tooth, anaesthesia and isolation are done and any existing restorations are removed. If there is no restoration, a round bur is inserted along the central groove till the defect is exposed. Care should be taken nor to penetrate the pulp. If hyperemic symptoms are present, the tooth can be temporized with zinc oxide eugenol. The tooth is relieved out of occlusion and a well fitting copper band is placed around the tooth to prevent propagation of the crack. If no further symptoms are manifested, a final restoration can be done.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;200
65. How is fracture involving the pulp treated?
If the crack involves the pulp of a vital tooth, endodontic treatment has to be done immediately. Periodontal condition is checked by probing. Occlusion is relieved and a tight fitting copper band is placed around the tooth. Recall after 15 days may or may not have symptoms. If symptoms have subsided, the final restoration is given. Intraradicular posts are not used to avoid the wedging effect. When the symptoms do not subside, final restoration is postponed till the patient is symptom free. If prognosis is poor, hemisection or extraction may be performed.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;201
66. What is the prognosis of fractures crossing the attachment apparatus?
In such fractures, the pulp is necrotic and the x rays show bone loss. Those cases can be treated as pulpo periodontal lesions depending on the severity of the case and the request of the patient. The prognosis is guarded.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;201,202
67. Why is extraction advised for a tooth with class IV fracture?
Class IV fracture refers to a fracture dividing the tooth in half. Except for some upper premolars with 2 roots and some upper molars where one root can be retained after RCT, the divided tooth has to be extracted.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;203
68. What is the fate of the remaining micro organisms entrapped in the canal after a three dimensional obturation?
The micro organisms in a three dimensionally sealed root canal get entrapped in the dentinal tubules between the cementum on one side and the canal filling material on the other side. They become non viable within 5 days after root canal therapy if there is a perfect seal.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;163
69. How does three dimensional seal result in a successful root canal therapy?
Sealing the canal three dimensionally helps for the success of the therapy since leaving any unfilled portion or unsealed areas will give space and food for the trapped bacteria leading to a failure of the endodontic therapy.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;163
70. What are the lysosomal hydrolytic enzymes that aid in the resorption of bony trabeculae?
Acid phophatase, beta–glucuronidase, hyaluronidase and elastase are the lysosomal hydrolytic enzymes.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;174
71. What are the three main sources for the hydrolytic enzymes?
Inflammatory cells which are the principal source, degenerating pulp or periradicular tissue and micro organisms are the three main sources of hydrolytic enzymes.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;174
72. Why does a lesion remain chronic?
The irritating substances within the root canal need to be removed and if not removed, the destructive phenomena along with the reparative processes continue indefinitely leading to the persistence of a chronic lesion.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;175
73. In acute apical periodontitis, why does the patient report that the tooth feels longer?
This is because of the slight extrusion of the tooth from the alveolus which is caused by the accumulation of the exudates between the fibers of the ligament and stretching of these fibers causes this sensation.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
74. Why is vitality test necessary to reach an accurate diagnosis in acute apical periodontitis?
The symptoms of acute apical periodontitis can occur both in vital as wellas in non vital teeth. so vitality test is essential to arrive at an accurate diagnosis.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
75. How is acute apical periodontitis due to occlusal trauma managed?
In acute apical periodontitis due to occlusal trauma, simple adjustment of the occlusion leads to rapid healing.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;185
76. What are the other etiological factors associated with incomplete crown root fractures?
Abnormal chewing habits, accidental trauma, stone in rice, chewing hard food like betel nuts and tongue piercings.
Ref: Endodontics,Arnaldo Castelluci,IL Tridente, vol 1;194