Fitting the master gutta-percha cone. A, Cone fit to radiographic terminus. B, Cone is cut back 0.5 mm.When placed to depth, the incisal reference remains the same. C, Compaction film reveals two apical foramina as well as large lateral canal opposite lateral lesion.
A, Bony lesion in furcation draining through buccalgingival sulcus. The molar pulp is necrotic. B, Obturation reveals the lateral accessory canal. C, Three-year recall radiograph. Total healing is apparent. No surgery was used.
A vital coronal pulp and associated periradicularresorptive lesions (arrows), most likely to occur in young persons, as demonstrated by a newly erupted, but cariously involved, second molar in a 15-year-old patient. Usually, a periradicular lesion is associated with necrotic pulp, as is the case on the first molar.
An avulsed left central incisor in a 6-year-old boy was replanted immediately. A,When re-evaluated after 8 weeks, there was still response to electric pulp testing. B, One year after trauma, the tooth was in the normal position and had no discoloration but did not respond to electric pulp testing. The root has continued to develop and the pulp appears to be calcifying. Also note hourglass erosion/resorption cervically(arrows). (Courtesy of Dr. Robert Bravin.)
Advanced internal resorption of a first molar. The process spread distally from the pulp to undermine restoration and perforate externally. The pulp is now necrotic, as evidenced by inflammatory lesion at apex. The cause of internal resorption may be from deep caries, pulp cap, or trauma from extraction of the second molar.
Differing pulp responses to trauma. Both incisors suffered impact as well as caries and restorative trauma. It is not clear why one pulp may react with extensive internal resorption and why another pulp may form calcifications. Treatment was successful in the central incisor but unsuccessful in the lateral incisor; the “cork-in-a-sewer” retrofilling failed.
Extensive internal resorption apparently triggered by iatral causes. Normal condition of teeth prior to crown preparation is seen in “before” radiographs (A and B). Development of internal resorption from high-speed preparation without water coolant is seen 1 year later (C and D).
External inflammatory resorption. A, Accidentally luxated tooth, radiograph taken 8 weeks after the incident. Note resorption of both dental hard tissues as well as adjacent alveolar bone. B, Immediately after root canal therapy. C, Control radiograph taken 12 months later. Note repair of the alveolus and establishment of a new periodontal ligament space. The root canal procedure arrested the resorptive process. (Courtsey of Dr. Romulo de Leon.)Figure 15-33 A, Internal resorption with a history of trauma. B, Immediately following root canal therapy.
Fractured premolar restored by endodontics and post-and-core crown. A, Tooth immediately following fracture. B, Restoration and periradicular healing at 3-year recall. Note the spectacular fill of arborization (arrows) at the apex. (Courtesy of Dr. Clifford J. Ruddle.)
Root fractures involve cementum, dentin, and pulp and may occur in any part of the root: apical, middle, or coronal thirds. B, Fractures may also be Comminuted (arrows).
A,Healing by interproximal bone. B, Root fracture (arrow) resulting in total separation of fragments. C,Midroot facture stabilizedfor 3 months. D, Note that after removing the splint, the incisal edges are even, yet a space is apparent between the segments. E, Eightmonths later, bone is now apparent between segments. F, The interproximal space has enlarged further 2 years after the accident. The toothis firm and functional. Note calcification of the pulp space.
C, Pulps of three incisors have been devitalized by the force of traumatic habit. Acute abscess has separated central incisors. D, One year following root canal therapy, some repair has occurred; however, persistent habit prevents complete healing.
Tooth luxation with loosening and displacement is often accompanied by fracture or comminution of the alveolar socket. B, Luxation displacement of left central and lateral incisor and canine (arrows). C, After repositioning. D, The incisor required root canal therapy about 3 months later. Canine retained its pulp vitality.
Apical condensing osteitis that developed in response to chronic pulpitis. Additional bony trabeculae have been formed and marrow spaces have been reduced to a minimum. The periodontal ligament space is visible, despite increased radiopacity of nearby bone.
Figure 5-9 A, Apical condensing osteitis associated with chronic pulpitis. Endodontic treatment has just been completed. Obvious condensation of alveolar bone (black arrow) is noticeable around the mesial root of the first molar. Radiolucent area is evident at the apex of the distal root of the same tooth. The retained primary molar root tip (open arrow) lies within the alveolar septum mesialto the molar. B, Resolution (arrow) of apical condensing osteitisshown in A, 1 year after endodontic treatment. From a radiographic standpoint, complete repair of both periradicular lesions has been obtained. Reversal of apical condensing osteitis and disappearance of radiopaque area are possible.
Enostosis. Also known as sclerotic bone. The radiopaque mass (arrows) probably represents an outgrowth of cortical bone on the endosteal surface. It is associated with neither pulpal nor periradicularpathosis and can be differentiated radiographically from condensing osteitis (see Figure 5-9) by its well-defined borders and homogeneous opacity
Circumferential dentigerous cyst developed around the crown of an unerupted canine. The cyst may be enucleated (care must be taken to avoid the incisor) and the canine brought into position with an orthodontic appliance.
Initial – Later – Intermediate - Mature
Unusual pulp dystrophy seen with hereditary hypophosphatemia. Incomplete calcification of dentin and huge pulps leave these teeth vulnerable to pulp infection and necrosis.
Radiology in Endodontics
RADIOLOGY INENDODONTICs Presented By Jean Michael 1
History• 1895 – Discovery of cathode rays by Roentgen• 1895 – Dr. Otto Walkoff took the 1st dental X ray (of his own teeth)• 1899 – Dr. Edmund Kells used Radiographs to determine the root length during RCT• 1900 – Dr. Weston Price advocated the use of radiographs to check the adequacy of root canal fillings 2
How To Obtain A Good Radiograph1. Proper placement of film in the patient’s mouth2. Correct Angulation of the cone in relation to the film and oral structures3. Correct exposure time4. Proper developing technique 3
Relevant Findings For An Endodontist• Presence of Caries that may involve or threaten to involve the Pulp• Number, course, shape and length of root canals• Calcification or obliteration of pulp cavity• Internal and External Resorption• Thickening of Periodontal Ligament• Nature and extend of Periapical and Alveolar Bone Destruction 4
• Diagnose abnormalities like Dilaceration and Taurodontism• Diagnose fracture of root• To estimate and confirm the length of root canals before instrumentation (working length determination)• To confirm the position and adaptation of master cone• Evaluation of outcome of root canal therapy (post operative radiograph) 5
Disadvantages of Radiographs• Radiographs are 2D shadow of a 3D Object• They are only suggestive and not the final evidence in judging a clinical problem• Bucco-lingual dimension cannot be assessed in an IOPA• The bacterial status of the hard and soft tissues cannot be determined• Chronic inflammatory tissues cannot be differentiated from healed fibrous scar tissue 12
• Lesions of the medullary bone are undetected in the radiographs till there is substantial bone loss and the involvement of cortical bone• For a hard tissue lesion to be evident on a radiograph, there should be at least a mineral loss of 6.6 %• Even a single error in the procedure can render a radiograph useless• Over exposure to X rays are harmful to the body and strict precautions are to be maintained for the patient and the operator 13
ParallelingTechnique• Film is placed parallel to the long axis of the tooth to be radiographed• The film is exposed using X rays which are perpendicular to its surface• Requires special film holding devices 15
IOPA Radiographs in Endodontic Therapy• Diagnostic Radiographs• Working Radiographs• Post operative Radiographs• Follow up Radiographs 47
Diagnostic Radiographs• Ideally, these radiographs should be taken using paralleling angle technique• They should be of high quality without any foreshortening or elongination• They help for proper diagnosis of the case• These radiographs helps in determining the prognosis by comparison with post operative and follow up radiographs 48
Comparison between Diagnostic and Follow up Radiographs Periapical Cyst Before RCT Complete Bony repair after RCT 50
Working Radiographs• These radiographs are used for determining the position of instruments – files etc during the procedure• These radiographs are to be taken without removing the rubber dam as it can cause contamination of the operating field• Bisecting angle technique can be used• A better alternative is the use of a hemostat as a film holding device 51
Radiograph showing EndodonticInstruments & Rubber Dam Clamp 52
Working Radiographs of same tooth using Different Angulations 54
Advantages of using a Hemostat• Film placement is easier when the opening is restricted by the Rubber dam and frame• In the mandibular posterior area, the closing of mouth relaxes the mylohyoid muscle permitting the film to be placed farther apically 55
• The handle of the hemostat is a guide to align the cone in a proper vertical and horizontal angulation• There is less risk of distortion caused by finger pressure and film displacement as in bisecting angle technique• Any movement can be detected by the shift of the handle and corrected before the exposure 56
Postoperative Radiographs• They are used to evaluate the endodontic treatment• They are taken after removing the rubber dam• Ideally paralleling angle technique should be used• They can be compared with the diagnostic radiograph 63
Overextension into Inferior Alveolar Canal leading to Permanent Paresthesia 67
Follow-up Radiographs• These radiographs are taken to evaluate the prognosis of the endodontically treated tooth• After obturation, the tooth may have to undergo procedures like core build up, crown fabrication etc• The follow up radiograph gives the health of the periodontium and the tooth by evaluating the presence of root resorption, other treatment failures etc 68
Vertical Angulation• Elongation – Corrected by increasing the vertical angle of the central ray• Foreshortening – Corrected by decreasing the vertical angle of the central ray 74
Horizontal AngulationClarke’s Rule (S.L.O.B Rule)• The object that moves in the SAME direction as the cone is located toward the LINGUAL• The object that moves in the OPPOSITE direction as the cone is located toward the BUCCAL 75
• The digital systems relies on an electronic detection of an X ray generated image that is electronically processed and reproduced on a computer screen 106
Advantages• Reduced exposure to radiation• Increased speed of obtaining the image• Possibility for digital enhancement• Storage as digital data in computers• Ease of transmissibility• Elimination of manual processing steps 107
Conclusion• Radiograph is a very powerful tool for a dentist, especially an Endodontist with which he are able to examine the status of hard tissue which are beyond the field of his naked eyes• Application of radiology gives new standards for the diagnosis, treatment and prognosis of a dental problem 117