- Email: [email protected]
Root perforations
mouthguards that are used are the self-fitted type, professionally fitted mouthguards are more durable and provide a better fit. Dentists can provide these devices and ensure that they are comfortable and do not impede breathing or speech.
Collins CL, McKenzie LB, Ferketich AK, et al: Dental injuries sustained by high school athletes in the United States, from 2008/ 2009 through 2013/2014 academic years. Dent Trauma 32:121127, 2016 Reprints available from C Collins, OhioHealth Research & Innovation Inst, 3545 Olentangy River Rd, NMB Suite 310, Columbus, OH 43214; e-mail: [email protected]
Endodontics Root perforations Background.—A perforation is an opening that develops between the periodontium and the root canal space. The disorder can result from caries or resorptive defects, but most occur during or after root canal therapy and are iatrogenic. As many as 10% of the endodontic cases that fail do so as a result of perforation. The etiology, diagnosis, and management of root perforations were outlined.
the perforations result during post insertion, with the remainder occurring during routine endodontic treatment. Three fourths of the cases affect the maxilla and the rest the mandibular arch. When they are found in multi-rooted teeth, furcation perforations can occur when the clinician is searching for canal orifices because dentin is removed from the pulpal floor.
Etiology.—Iatrogenic perforations most often occur while the clinician is seeking to locate and open canals. Calcifications in the pulp chamber and orifices, mistaken identification of canals, significant crown-root angles, and extreme removal of coronal dentin can cause perforations in the coronal or furcation area.
Iatrogenic perforations are obvious by the profuse bleeding after the injury. There may also be sudden unexpected pain that will signal a perforation has occurred during treatment. Apex locators can detect perforations, as can operating microscopes. Radiographs can be limited in their ability to visual perforations, since they are twodimensional representations and it can be difficult to access the site and extent of a perforation.
In addition, strip perforations of the middle third can result from overzealous instrumentation of canals. Canal preparation is also sometimes the cause of perforation, usually in curved molar roots. Seeking sclerosed canals can cause perforation laterally. The apical third can be perforated during inadequate cleaning and shaping of the canal, a process that can cause blockages and ledges that shift instruments away from the center of the canal. Apical perforation can result when endodontic files are passed too aggressively through the apical constriction. Post-space preparation done carelessly can result in perforation as well. Along with root resorption and extensive caries, perforation can occur after trauma, pulpal inflammation, and pulpotomy procedures. External inflammatory root resorption can occur when the cementum and periodontal ligament cells on the root surface are injured. Epidemiology and Diagnosis.—As more complex endodontic treatment cases are being performed, it’s likely that the frequency of perforation will increase. Today over half of
Pathological perforations are diagnosed late because of the combination of clinical assessment, radiographic evidence, and the presenting complaint. Serous exudate or sinus can appear at the site of the perforation. Patients may experience sensitivity to percussion, have localized periodontal pocketing, or experience chronic inflammation of the gingival if the inflammation penetrates the alveolar bone. Radiolucent lesions may appear on radiographs. Cone beam computed tomography (CBCT) can accurately identify and assess resorptive lesions and post perforations, but the patient is exposed to higher levels of ionizing radiation than with traditional radiographs. CBCT is advised only if the findings could change the clinical outcome for the patient. Other factors that must be considered when diagnosing perforations include the possibility of destruction of periodontal fibers, bone resorption, and granulomatous tissue formation. Tooth loss may also result. If an irritating restoration is present or infection develops, healing is unlikely. Thus root canal treatment has just a 50% chance of success in these cases. Clinicians must consider the site of the
Volume 61
Issue 6
2016
311
Table 1.—The Prognosis for Success When Considering Site, Size, and Time to Repair of Perforations Prognosis
Favourable Unfavorable
Site
Size
Apical or supra-crestal Equi-crestal
Small Large
Time to repair
Immediate Delayed
(Courtesy of Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171180, 2016.)
of the hole, delay between perforation and repair, and the use of appropriate repair material all contribute to the success or failure of treatment (Table 1).
Fig 10.—The critical zone: A perforation into the gingival sulcus and the crestal attachment may have the most significant consequences as bacterial entry and pocket formation can quickly ensue. It is important to recognize the critical zone may not necessarily be at the cementoenamel junction (CEJ) but rather follows the biological width, thus if there is recession, the critical zone will be located more apically accordingly. (Courtesy of Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171-180, 2016.)
perforation relative to the level of the crestal bone and the epithelial attachment, termed the critical zone (Fig 10). Prognosis is tied to the exact site of the perforation. Size
Management.—Management efforts are designed to regenerate healthy periodontal tissues against the perforation without persistent inflammation or loss of periodontal attachment. If periodontal breakdown occurs, tissue reattachment is the goal. Successful repair relies on the clinician’s ability to seal the perforation and re-establish a healthy periodontal ligament. If the patient has symptoms, treatment is required and involves either repair or extraction. Assessment is done to determine if the tooth can be restored or if extraction is the only option or the best option given the collateral damage or risk of failure. An important factor in restoration is the ability to visualize the perforation site. An operating microscope is recommended for repairs. Nonsurgical management involves root canal treatment and definitive obturation. If these cannot be achieved, the canals should be protected by an easily removed material
Fig 23.—Key concepts to avoid perforation during endodontic treatment. (Courtesy of Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171-180, 2016.)
312
Dental Abstracts
to block iatrogenic blockage of the canals by reparative material. If a non-contaminated perforation is repaired immediately, periodontal ligament damage can be avoided. If repair is delayed, chronic infection may have developed. Restorative material in the perforation defect is removed. Dentin removal, if needed, is accomplished using burs or ultrasonic instruments under magnification. Ultrasonic tips are less destructive to adjacent tissues. Irrigation is done with sodium hypochlorite, sterile water, or chlorhexidine. For larger lesions with granulation tissue, the granulation tissue should be curetted and removed carefully. The clinician should seek to provide a clean cavity, although profuse bleeding can be stimulated. Clotting agents can irreversibly damage the delicate alveolar bone and delay healing, so they are contraindicated. Collagen, calcium sulfate, or calcium hydroxide may be used to achieve hemostasis. If bleeding cannot be controlled, the tooth may be dressed and filled provisionally. With delayed repair, the periodontal ligament and surrounding bone are invariably damaged. When the granulation tissue is removed, a bone cavity is left around the perforation site, which is likely to allow extrusion of repair material. Evidence suggests that excellent results are achieved when mineral trioxide aggregate (MTA) is used without barriers. A barrier may be placed to facilitate control of material, however. Clinicians must tailor their nonoperative treatment to the site of the perforation. Different approaches are needed for coronal third, middle third, and apical third perforations because of the anatomic differences and resulting perforation forms. The surgical management of perforations may be considered if there is uncertainty about the shape or nature of the defect; if the defect is located subcrestally and associated with pathology and/or symptoms; when internal access is not possible because an extensive intracoronal and/or extracoronal restoration is in place; if a large defect prevents material control; when the apical third perforation has persistent disease and does not allow adequate
cleansing or repair; or if there is an external cervical resorption not amenable to internal repair. The surgical management includes root canal treatment, surgical flaps as needed, and papilla base preservation techniques or submarginal incisions. Piezo-electric ultrasonic handpieces may be used for preparation or a small round bur may be sufficient. Often simple hand instrumentation with curettes is effective. Hemostasis is achieved, then a biologically compatible material is thoroughly compacted into the cavity, ensuring a dense fill. Because of the moisture requirements of MTAtype materials or resin bonded materials, resin-modified glass-ionomer cement may be required. Any bony cavities are carefully debrided and the debris removed before flap replacement. Success rates with these approaches vary from 30% to 80%. In light of the complications associated with surgery, nonsurgical repair is the preferred choice whenever possible.
Clinical Significance.—Clinicians should take every precaution to avoid perforation when delivering root canal therapy (Fig 23). Prevention of iatrogenic damage is essential to good practice, avoiding most perforations. Referral to a more experienced colleague may delay treatment, so all clinicians should consider immediate repair with the most appropriate materials. Patients who have had perforations for some time should be informed of the unpredictability of repair options and counseled about the risks and benefits of leaving the tooth unprepared or performing an extraction and replacement procedure.
Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171-180, 2016 Reprints available hotmail.com
from
SM
Saed;
e-mail:
sarasaed1234@
Long-term survival of nonsurgical root canal therapy Background.—US dentists complete over 15 million root canal procedures each year, with nonsurgical root canal therapy (NSRCT) proving highly effective in retaining
teeth that would have been lost without treatment. The success of NSRCT has been variously defined as reducing or eliminating apical lesions and an absence of clinical
Volume 61
Issue 6
2016
313
Collins CL, McKenzie LB, Ferketich AK, et al: Dental injuries sustained by high school athletes in the United States, from 2008/ 2009 through 2013/2014 academic years. Dent Trauma 32:121127, 2016 Reprints available from C Collins, OhioHealth Research & Innovation Inst, 3545 Olentangy River Rd, NMB Suite 310, Columbus, OH 43214; e-mail: [email protected]
Endodontics Root perforations Background.—A perforation is an opening that develops between the periodontium and the root canal space. The disorder can result from caries or resorptive defects, but most occur during or after root canal therapy and are iatrogenic. As many as 10% of the endodontic cases that fail do so as a result of perforation. The etiology, diagnosis, and management of root perforations were outlined.
the perforations result during post insertion, with the remainder occurring during routine endodontic treatment. Three fourths of the cases affect the maxilla and the rest the mandibular arch. When they are found in multi-rooted teeth, furcation perforations can occur when the clinician is searching for canal orifices because dentin is removed from the pulpal floor.
Etiology.—Iatrogenic perforations most often occur while the clinician is seeking to locate and open canals. Calcifications in the pulp chamber and orifices, mistaken identification of canals, significant crown-root angles, and extreme removal of coronal dentin can cause perforations in the coronal or furcation area.
Iatrogenic perforations are obvious by the profuse bleeding after the injury. There may also be sudden unexpected pain that will signal a perforation has occurred during treatment. Apex locators can detect perforations, as can operating microscopes. Radiographs can be limited in their ability to visual perforations, since they are twodimensional representations and it can be difficult to access the site and extent of a perforation.
In addition, strip perforations of the middle third can result from overzealous instrumentation of canals. Canal preparation is also sometimes the cause of perforation, usually in curved molar roots. Seeking sclerosed canals can cause perforation laterally. The apical third can be perforated during inadequate cleaning and shaping of the canal, a process that can cause blockages and ledges that shift instruments away from the center of the canal. Apical perforation can result when endodontic files are passed too aggressively through the apical constriction. Post-space preparation done carelessly can result in perforation as well. Along with root resorption and extensive caries, perforation can occur after trauma, pulpal inflammation, and pulpotomy procedures. External inflammatory root resorption can occur when the cementum and periodontal ligament cells on the root surface are injured. Epidemiology and Diagnosis.—As more complex endodontic treatment cases are being performed, it’s likely that the frequency of perforation will increase. Today over half of
Pathological perforations are diagnosed late because of the combination of clinical assessment, radiographic evidence, and the presenting complaint. Serous exudate or sinus can appear at the site of the perforation. Patients may experience sensitivity to percussion, have localized periodontal pocketing, or experience chronic inflammation of the gingival if the inflammation penetrates the alveolar bone. Radiolucent lesions may appear on radiographs. Cone beam computed tomography (CBCT) can accurately identify and assess resorptive lesions and post perforations, but the patient is exposed to higher levels of ionizing radiation than with traditional radiographs. CBCT is advised only if the findings could change the clinical outcome for the patient. Other factors that must be considered when diagnosing perforations include the possibility of destruction of periodontal fibers, bone resorption, and granulomatous tissue formation. Tooth loss may also result. If an irritating restoration is present or infection develops, healing is unlikely. Thus root canal treatment has just a 50% chance of success in these cases. Clinicians must consider the site of the
Volume 61
Issue 6
2016
311
Table 1.—The Prognosis for Success When Considering Site, Size, and Time to Repair of Perforations Prognosis
Favourable Unfavorable
Site
Size
Apical or supra-crestal Equi-crestal
Small Large
Time to repair
Immediate Delayed
(Courtesy of Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171180, 2016.)
of the hole, delay between perforation and repair, and the use of appropriate repair material all contribute to the success or failure of treatment (Table 1).
Fig 10.—The critical zone: A perforation into the gingival sulcus and the crestal attachment may have the most significant consequences as bacterial entry and pocket formation can quickly ensue. It is important to recognize the critical zone may not necessarily be at the cementoenamel junction (CEJ) but rather follows the biological width, thus if there is recession, the critical zone will be located more apically accordingly. (Courtesy of Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171-180, 2016.)
perforation relative to the level of the crestal bone and the epithelial attachment, termed the critical zone (Fig 10). Prognosis is tied to the exact site of the perforation. Size
Management.—Management efforts are designed to regenerate healthy periodontal tissues against the perforation without persistent inflammation or loss of periodontal attachment. If periodontal breakdown occurs, tissue reattachment is the goal. Successful repair relies on the clinician’s ability to seal the perforation and re-establish a healthy periodontal ligament. If the patient has symptoms, treatment is required and involves either repair or extraction. Assessment is done to determine if the tooth can be restored or if extraction is the only option or the best option given the collateral damage or risk of failure. An important factor in restoration is the ability to visualize the perforation site. An operating microscope is recommended for repairs. Nonsurgical management involves root canal treatment and definitive obturation. If these cannot be achieved, the canals should be protected by an easily removed material
Fig 23.—Key concepts to avoid perforation during endodontic treatment. (Courtesy of Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171-180, 2016.)
312
Dental Abstracts
to block iatrogenic blockage of the canals by reparative material. If a non-contaminated perforation is repaired immediately, periodontal ligament damage can be avoided. If repair is delayed, chronic infection may have developed. Restorative material in the perforation defect is removed. Dentin removal, if needed, is accomplished using burs or ultrasonic instruments under magnification. Ultrasonic tips are less destructive to adjacent tissues. Irrigation is done with sodium hypochlorite, sterile water, or chlorhexidine. For larger lesions with granulation tissue, the granulation tissue should be curetted and removed carefully. The clinician should seek to provide a clean cavity, although profuse bleeding can be stimulated. Clotting agents can irreversibly damage the delicate alveolar bone and delay healing, so they are contraindicated. Collagen, calcium sulfate, or calcium hydroxide may be used to achieve hemostasis. If bleeding cannot be controlled, the tooth may be dressed and filled provisionally. With delayed repair, the periodontal ligament and surrounding bone are invariably damaged. When the granulation tissue is removed, a bone cavity is left around the perforation site, which is likely to allow extrusion of repair material. Evidence suggests that excellent results are achieved when mineral trioxide aggregate (MTA) is used without barriers. A barrier may be placed to facilitate control of material, however. Clinicians must tailor their nonoperative treatment to the site of the perforation. Different approaches are needed for coronal third, middle third, and apical third perforations because of the anatomic differences and resulting perforation forms. The surgical management of perforations may be considered if there is uncertainty about the shape or nature of the defect; if the defect is located subcrestally and associated with pathology and/or symptoms; when internal access is not possible because an extensive intracoronal and/or extracoronal restoration is in place; if a large defect prevents material control; when the apical third perforation has persistent disease and does not allow adequate
cleansing or repair; or if there is an external cervical resorption not amenable to internal repair. The surgical management includes root canal treatment, surgical flaps as needed, and papilla base preservation techniques or submarginal incisions. Piezo-electric ultrasonic handpieces may be used for preparation or a small round bur may be sufficient. Often simple hand instrumentation with curettes is effective. Hemostasis is achieved, then a biologically compatible material is thoroughly compacted into the cavity, ensuring a dense fill. Because of the moisture requirements of MTAtype materials or resin bonded materials, resin-modified glass-ionomer cement may be required. Any bony cavities are carefully debrided and the debris removed before flap replacement. Success rates with these approaches vary from 30% to 80%. In light of the complications associated with surgery, nonsurgical repair is the preferred choice whenever possible.
Clinical Significance.—Clinicians should take every precaution to avoid perforation when delivering root canal therapy (Fig 23). Prevention of iatrogenic damage is essential to good practice, avoiding most perforations. Referral to a more experienced colleague may delay treatment, so all clinicians should consider immediate repair with the most appropriate materials. Patients who have had perforations for some time should be informed of the unpredictability of repair options and counseled about the risks and benefits of leaving the tooth unprepared or performing an extraction and replacement procedure.
Saed SM, Ashley MP, Darcey J: Root perforations: Aetiology, management strategies and outcomes. The hole truth. Br Dent J 220:171-180, 2016 Reprints available hotmail.com
from
SM
Saed;
e-mail:
sarasaed1234@
Long-term survival of nonsurgical root canal therapy Background.—US dentists complete over 15 million root canal procedures each year, with nonsurgical root canal therapy (NSRCT) proving highly effective in retaining
teeth that would have been lost without treatment. The success of NSRCT has been variously defined as reducing or eliminating apical lesions and an absence of clinical
Volume 61
Issue 6
2016
313