Revascularization of immature permanent teeth with apical periodontitis: new treatment protocol?

A new technique is presented to revascularize immature permanent teeth with apical periodontitis. The canal is disinfected with copious irrigation and a combination of three antibiotics. After the disinfection protocol is complete, the apex is mechanically irritated to initiate bleeding into the canal to produce a blood clot to the level of the cemento-enamel junction. The double seal of the coronal access is then made. In this case, the combination of a disinfected canal, a matrix into which new tissue could grow, and an effective coronal seal appears to have produced the environment necessary for successful revascularization.

Immediate placement of implants in periapical infected sites: a prospective randomized study in 50 patients

OBJECTIVE

To determine clinical success when implants are placed in chronic periapical infected sites.

STUDY DESIGN

Fifty patients (25 females, 25 males, mean age 39.7 +/- 14.5 years) were included in this prospective controlled study. After randomization, 25 Frialit-2 Synchro implants were immediately placed (IP) after extraction, and 25 Frialit-2 Synchro implants were placed after a 3-month healing period (DP). Thirty-two implants were placed in the anterior maxilla and 18 implants were placed in the premolar region. Implant survival, mean Implant Stability Quotient (ISQ) values, gingival aesthetics, radiographic bone loss, and microbiologic characteristics of periapical lesions were evaluated for both groups.

RESULTS

Overall, 2 implants belonging to the IP group were lost, resulting in a survival rate of 92% for IP implants versus 100% for DP implants. Mean ISQ, gingival aesthetics and radiographic bone resorption, and periapical cultures were not significantly different with the IP and DP implants.

CONCLUSIONS

Immediate implant placement in chronic periapical lesions may be indicated.

Assessment of periradicular microbiota by DNA-DNA hybridization

In the present study the "checkerboard" DNA-DNA hybridization technique was used to identify bacteria in periapical endodontic lesions of asymptomatic teeth. Thirty-four patients with root-filled teeth and apical periodontitis were divided into two groups, each containing 17 patients. In Group 1, a marginal incision was performed during surgery to expose the lesion, and in Group 2, a submarginal incision was applied. The gingiva and mucosa were swabbed with an 0.2% chlorhexidine gluconate solution prior to surgery. Bacterial DNA was identified in all samples from the two groups using 40 different whole genomic probes. The mean number (+/- SD) of species detected was 33.7 +/- 3.3 in Group 1 and 21.3 +/- 6.3 in Group 2 (P < 0.001). The majority of the probe-detected bacteria were present in more lesions from Group 1 than from Group 2. The differences were most notable for Campylobacter gracilis, Porphyromonas endodontalis, Propionibacterium acnes, Capnocytophaga gingivalis, Fusobacterium nucleatum ssp. nucleatum, Fusobacterium nucleatum ssp. polymorphum, Prevotella intermedia, Treponema denticola, Streptococcus constellatus and Actinomyces naeslundii I. Bacterial species such as Actinobacillus actinomycetemcomitans and Bacteroides forsythus were detected in more than 60% of the lesions from both groups. Also, P. endodontalis was abundant in periapical tissue. The data supported the idea that following a marginal incision, bacteria from the periodontal pocket might reach the underlying tissues by surgeon-released bacteremia. The study provided solid evidence that bacteria invade the periapical tissue of asymptomatic teeth with apical periodontitis. The detection of much more bacteria with the "checkerboard" DNA-DNA hybridization method than has previously been recovered by anaerobic culture indicated that the endodontic (and periodontal) microfloras should be redefined using molecular methods.

Periapical endodontic surgery: a 3-year follow-up study

AIM

To monitor the outcome of periradicular surgery in a group of teeth treated with microsurgical technology and ultrasonic root-end preparation.

METHODOLOGY

One hundred and twenty-eight teeth with failed conventional root canal treatment were included. The surgical procedure was completed using ultrasonic retrotips and a zinc oxide-EBA (Super Seal, Ogna Pharmaceuticals. Milan, Italy)-reinforced material was used to seal the root end cavities. Lesions were examined radiologically at 1. 3. 6. 12, 24 and 36-month intervals. Radiographs were independently analysed according to a previously published classification.

RESULTS

Eight teeth were extracted due to fracture or perforations undetected radiologically: these cases were excluded from the study. Of the 120 teeth examined. the overall success rate was 92.5%; 94 healed with complete bone filling of the surgical cavity, 17 were considered to have healed by apical scar formation, four demonstrated uncertain healing and five were considered failures. Eighty of 120 teeth examined had successfully healed from a radiological point of view within 12 months. No differences in outcome occurred between anterior, premolar and molar teeth. Although all failures occurred in teeth with posts, no statistically significant difference was noted (Mann-Whitney U-test, P = 0.37).

CONCLUSION

Modern surgical endodontic procedures associated and ERA (Super Seal, Ogna Pharmaceuticals, Milan, Italy) root end fillings were successful over 3 years in 92.5% of cases.

Clinical and Radiographic Assessment of Various Predictors for Healing Outcome 1 Year After Periapical Surgery

This clinical study prospectively evaluated the influence of various predictors on healing outcome 1 year after periapical surgery. The study cohort included 194 teeth in an equal number of patients. Three teeth were lost for the follow-up (1.5% drop-out rate). Clinical and radiographic measures were used to determine the healing outcome. For statistical analysis, results were dichotomized (healed versus nonhealed). The overall success rate was 83.8% (healed cases). The only individual predictors to prove significant for the outcome were pain at initial examination (p=0.030) and other clinical signs or symptoms at initial examination (p=0.042), meaning that such teeth had lower healing rates 1 year after periapical surgery compared with teeth without such signs or symptoms. Logistic regression revealed that pain at initial examination (odds ratio=2.59, confidence interval=1.2-5.6, p=0.04) was the only predictor reaching significance. Several predictors almost reached statistical significance: lesion size (p=0.06), retrofilling material (p=0.06), and postoperative healing course (p=0.06).

Immediate placement of dental implants into debrided infected dentoalveolar sockets

PURPOSE

To describe a protocol for the immediate placement of endosseous implants into debrided infected dentoalveolar sockets.

PATIENTS AND METHODS

A total of 30 implants were immediately placed into debrided infected sites in 20 patients. The pathology at the receptacle dentoalveolar sockets varied, and included subacute periodontal infection, perio-endo infection, chronic periodontal infection, chronic periapical lesion, and a periodontal cyst. The immediate placement protocol emphasized the meticulous debridement of the infected tissues in combination with peripheral ostectomy of the alveoli. Guided bone regeneration was accomplished to support bony healing of alveolar defects surrounding the implantation site. Pre- and postsurgical antibiotic therapy was administered.

RESULTS

All implants but 1 were osseointegrated and functional when followed up after 12 to 72 months. One implant was mobile after its immediate restoration and was removed. Complications were related to the use of guided bone regeneration. Deficiency of the attached gingiva was noted in 1 case. The treatment approach is illustrated in 2 anterior maxilla cases with 3-year follow-up.

CONCLUSIONS

Successful immediate implantation in debrided infected alveoli depends on the complete removal of all contaminated tissue and the controlled regeneration of the alveolar defect. With this proposed clinical approach, experienced clinicians may consider immediate implants as a viable treatment option in patients presenting with dentoalveolar infections.

Bacteria of asymptomatic periradicular endodontic lesions identified by DNA-DNA hybridization

Possible inclusion of contaminant bacteria during surgery has been problematic in studies of periradicular lesions of endodontic origin. Therefore, in this study, two different surgical techniques were compared. A second problem is that some difficult to cultivate species may not be detected using bacteriological methods. Molecular techniques may resolve this problem. DNA-DNA hybridization technology has the additional advantage that DNA is not amplified. The purpose of this investigation was to determine if bacteria from periradicular endodontic lesions could be identified using DNA-DNA hybridization. A full thickness intrasulcular mucoperiosteal (IS) flap (n = 20) or a submarginal (SM) flap (n = 16) was reflected in patients with asymptomatic apical periodontitis. DNA was extracted and incubated with 40 digoxigenin-labeled whole genomic probes. Bacterial DNA was detected in all 36 lesions. Seven probes were negative for all lesions. In patients with sinus tract communication, in teeth lacking intact full coverage crowns, and in patients with a history of trauma 4-13 probes provided positive signals. Seven probes were positive in lesions obtained by the IS, but not the SM technique. Two probes were in samples obtained with the SM technique, but not the IS. Only Bacteroides forsythus and Actinomyces naeslundii genospecies 2 were present in large numbers using either the IS or the SM technique. The SM flap technique, in combination with DNA-DNA hybridization, appeared to provide excellent data pertaining to periradicular bacteria. These results supported other studies that provide evidence of a bacterial presence and persistence in periradicular lesions.

Periapical surgery and the maxillary sinus: radiographic parameters for clinical outcome

OBJECTIVE

To find out whether conventional periapical radiographs can be used to determine the risk of creating an oroantral communication (OAC) while performing periapical surgery on maxillary premolars and molars.

STUDY DESIGN

One hundred thirteen periapical radiographs of maxillary premolars and molars with periapical radiolucencies indicating chronic apical periodontitis were retrospectively analyzed and classified. The surgery reports were evaluated for occurrence of perforation of the maxillary sinus and postoperative complications.

RESULTS

Perforation of the sinus membrane (also referred to as the Schneiderian membrane) occurred in 12 cases (9.6%). Exposure of the membrane without rupture occurred in 15 cases (12%). It was found that the distance between the apex or the periapical lesion and the sinus floor did not serve as a predictor of a possible sinus membrane rupture. On the other hand, if the radiograph showed a distinct distance between the lesion and the sinus floor, there was an 82.5% probability that OAC would not occur. Additionally, a blurred radiographic outline of the periapical lesion did not indicate an increased risk of sinus membrane rupture.

CONCLUSION

Conventional periapical radiographs cannot be used as predictors for perforation of the maxillary sinus during periapical surgery. However, radiographs with a specific distance between the periapical lesion and the sinus floor point toward a very low risk of accidental sinus perforation during periapical surgery.

Papilla base incision: a new approach to recession-free healing of the interdental papilla after endodontic surgery

AIM

The purpose of the present study was to describe and evaluate a new incision technique: the papilla base incision.

METHODOLOGY

Twenty healthy patients referred for surgical treatment of persisting apical periodontitis, who were free of periodontal disease and had intact interdental papillae were included in the study. The preoperative papilla height was recorded by measuring the distance between the contact point and the most coronal point of the papilla. The papilla base flap, consisting of the papilla base incision and two releasing incisions, was used to expose the bone. The papilla base incision consisted of a shallow first incision at the base of the papilla and a second incision directed to the crestal bone, creating a split thickness flap in the area of the papilla base. Further apically a full thickness flap was raised. Following standard root-end resection and filling, flap closure was achieved with microsurgical sutures. The papilla base incision was sutured with 2-3 interrupted sutures, which were removed 3-5 days after the surgery. The experimental sites were evaluated at the conclusion of the surgery, at suture removal and after 1 month, and compared to the preoperative findings. The healing pattern, complications and postoperative recession were recorded. The experimental sites were observed with a x 3 magnification and graded as to whether a visible scar resulting from the incision could be detected. Twenty experimental sites were analysed.

RESULTS

Complete closure of the wound was achieved in all cases after surgery. Except for four patients with delayed healing at suture removal, all other patients displayed rapid healing. No noticeable space was created beneath the contact point area. The change in distance between the reference point and the most coronal point of the papilla comparing the preoperative and the one-month postoperative situation was 0.05 +/- 0.39 mm. The probing depth remained within normal limits. One month postoperatively, observation of the incision demonstrated: four sites with a visible incision line (grade 1), in seven sites the incision defect could be partially detected (grade 2) and nine incisions could not be detected (grade 3).

CONCLUSIONS

In patients with healthy marginal periodontal conditions the papilla base incision allows rapid and predictable recession-free healing following marginal surgical exposure of the soft tissues. One month postoperatively the majority of the incisions were completely or partially invisible. Long-term healing will be studied.

Soft Tissue Management in Endodontic Surgery

Modern endodontic surgery involves both root-end preparation and proper sealing of all apical portals of exit. Both components are requirements for mechanical and biological success, but the management of soft tissues becomes increasingly important for an esthetically successful treatment. A healthy appearance of soft tissues plays an important role in the esthetic outcome of periradicular surgery. This is true considering maintenance of attachment levels and regarding the amount of possible recession after surgical procedures. Complete, recession-free and predictable healing of gingival tissue is one important goal of endodontic surgical treatment. A critical review of currently used techniques based on clinical and scientific data reveals great potential for improvements. Possible reasons for scar formation and recession specifically in healthy periodontal conditions requiring surgical endodontic intervention are highlighted. Based on anatomical considerations various incision types are evaluated and recommendations made. Clear understanding of wound closure and tissue-healing patterns call for the use of atraumatic procedures, nonirritating suture materials and adequate suturing techniques. This article gives an overview and guidance for integrating current and new successful flap designs and wound closure methods. The methods described have the intention of maintaining the attachment level and avoiding postoperative recession after surgical endodontic therapy.

Periodontal tissue disposition of azithromycin in patients affected by chronic inflammatory periodontal diseases

BACKGROUND

The recognition that periodontal diseases are associated with specific pathogens has led to interest in the use of antibacterial drugs for inhibition of these microorganisms. On these bases, the present study was aimed at evaluating the tissue distribution of the new macrolide antibiotic azithromycin in patients subjected to oral surgery for chronic inflammatory diseases of both marginal and periapical periodontium.

METHODS

Thirty-two patients were treated with azithromycin 500 mg/day orally for 3 consecutive days, and drug concentrations in plasma, saliva, normal gingiva, and pathological periodontal tissues were evaluated. For this purpose, samples of blood, saliva, normal gingiva, granulation tissue, and radicular granuloma or cyst wall (from dentigerous cyst) were collected during oral surgery or 0.5, 2.5, 4.5, and 6.5 days after the end of pharmacological treatment; then, azithromycin levels were measured by a microbiological plate assay, using Micrococcus luteus NCTC 8440 as the indicator organism.

RESULTS

The concentrations of azithromycin in plasma, saliva, normal gingiva, and pathological tissues reached the highest values 12 hours after the last dose (0.37+/-0.05 mg/l, 2.12+/-0.30 mg/l, 6.30+/-0.68 mg/kg, and 11.60+/-1.50 mg/kg, respectively) and then declined gradually. Consistent levels of the drug in normal gingiva and pathological tissues could be detected, however, up to 6.5 days, indicating that azithromycin was retained in target tissues for a long time after the end of treatment. Moreover, azithromycin levels in both normal gingiva and pathological tissues exceeded the minimum inhibitory concentrations of most pathogens involved in the pathophysiology of chronic inflammatory periodontal diseases. Notably, azithromycin levels in pathological tissues were significantly higher than those in normal gingiva 0.5, 2.5, and 4.5 days after the last dose.

CONCLUSIONS

The present results indicate a marked penetration of azithromycin into both normal and pathological periodontal tissues, suggesting that azithromycin represents a promising option in both adjunctive and prophylactic treatments of chronic inflammatory periodontal diseases.

Comparison of long-term papilla healing following sulcular full thickness flap and papilla base flap in endodontic surgery

AIM

To compare long-term loss of papilla height when using either the papilla base incision (PBI) or the standard papilla mobilization incision in marginal full thickness flap procedures in cases with no evidence of marginal periodontitis.

METHODOLOGY

Twelve healthy patients, free of periodontal disease, who had intact interdental papillae were referred for surgical treatment of persisting apical periodontitis and included in the study. The flap design consisted of two releasing incisions connected by a horizontal incision. The marginal incision involved the complete mobilization of the entire papilla in one interproximal space but in the other interproximal space the PBI was performed. Further apically a full thickness flap was raised. Following flap retraction, standard apical root-end resection and root-end filling was performed. Flap closure was achieved with microsurgical sutures. The PBI was sutured with two to three interrupted sutures (size 7/0), the elevated papilla was reapproximated with vertical mattress sutures (size 7/0), which were removed 3-5 days after the surgery. The height of the interdental papilla was evaluated preoperatively and postoperatively after 1-, 3- and 12-month recall using plaster replicas. The loss of papilla height was measured using a laser scanner. Papilla paired sites were evaluated and statistically analysed.

RESULTS

Most papilla recession took place within the first month after the surgery in the complete elevation of the papilla. Further small increase in loss of papilla height resulted at 3 months. After 1 year the loss of height diminished to 0.98 +/- 0.75 mm, but there was no statistical difference between the various recall intervals. In contrast, after PBI only minor changes could be detected at all times. There was a highly significant difference between the two incision techniques for all recall appointments (P < 0.001).

CONCLUSIONS

In the short as well as long-term the PBI allows predictable recession-free healing of the interdental papilla. In contrast, complete mobilization of the papilla displayed a marked loss of the papilla height in the initial healing phase although this was less evident 1 year postoperatively. In aesthetically relevant areas the use of the PBI is recommended, to avoid opening of the interproximal space, when periradicular surgical treatment is necessary.

Extraradicular infection as the cause of persistent symptoms: a case series

INTRODUCTION

This article describes 3 cases that presented persistent symptoms after appropriate endodontic treatment. Histopathologic and histobacteriologic investigation were conducted for determination of the cause.

METHODS

Three cases are reported that presented with persistent symptoms after endodontic retreatment (cases 1 and 2) or treatment (case 3). Periapical surgery was indicated and performed in these cases. The biopsy specimens, consisting of root apices and the apical periodontitis lesions, were subjected to histopathologic and histobacteriologic analyses.

RESULTS

Case 1 was an apical cyst with necrotic debris, heavily colonized by ramifying bacteria, in the lumen. No bacteria were found in the apical root canal system. Case 2 was a granuloma displaying numerous bacterial aggregations through the inflammatory tissue. Infection was also present in the dentinal tubules at the apical root canal. Case 3 was a cyst with bacterial colonies floating in its lumen; bacterial biofilms were also seen on the external apical root surface, filling a large lateral canal and other apical ramifications, and between layers of cementum detached from the root surface. No bacteria were detected in the main root canal.

CONCLUSIONS

Different forms of extraradicular infection were associated with symptoms in these cases, leading to short-term endodontic failure only solved by periapical surgery.

Efficacy of ultrasound and color power Doppler as a monitoring tool in the healing of endodontic periapical lesions

This study determined the efficacy of high-resolution ultrasound and color power Doppler as a monitoring tool in the healing of periapical lesions. Five patients with a periapical lesion in the maxillary anterior teeth were chosen for this study. A preoperative ultrasound with color power Doppler was done to analyze the features of the periapical lesion. These patients were then treated by nonsurgical endodontics and followed up on a regular basis. A 6-month postoperative ultrasound and Doppler study of the same lesion was done to observe the healing of the lesion compared with the preoperative images. The ultrasound with Doppler gave inferences of bone healing in all the lesions. This study demonstrates the application of ultrasound and color power Doppler as a viable and nonhazardous tool for monitoring the healing of periapical lesions.

Deep neck infection with dental origin: analysis of 85 consecutive cases (2000-2006)

CONCLUSIONS

Diagnostic work-up should include contrast-enhanced computed tomography (CT) and mandible orthopantogram. When a dental origin of deep neck infection is suspected, the intravenous antibiotic regimen has to be active against gram-positive bacteria, both aerobes and anaerobes. Surgical exploration and drainage may be mandatory at presentation, or in cases not responding to medical therapy within the first 24 h.

OBJECTIVES

Deep neck infections are still associated with significant morbidity and mortality rates when complications occur. Despite worldwide improvement in dental care and oral hygiene, a significant prevalence of deep neck infections caused by dental infections has been described recently (> 40%).

PATIENTS AND METHODS

We analysed retrospectively 85 cases of deep neck infection with dental origin out of 206 consecutive cases of deep neck infection diagnosed in our institution between 2000 and 2006.

RESULTS

The most frequent dental source was a periapical infection of the first mandibular molar, followed by second and third molar, respectively. Submandibular space infection involvement was diagnosed in 73 of 85 patients (85.9%), masticatory space infection in 28 (32.9%); in 56 patients (65.9%) the infection involved more than one space. Twenty-four patients (28.2%) were treated only with intravenous antibiotic therapy; 61 patients (71.8%) required both medical and surgical procedures.

Diagnosis and treatment of a large periapical implant lesion associated with adjacent natural tooth: a case report

A possible cause for dental implant failure is the periapical implant lesion (PIL). In this case report we describe an apical periodontitis on a tooth adjacent to a dental implant that may have communicated with the apical region of the dental implant, and causing retrograde peri-implantitis. To our knowledge this is the first report demonstrating the concomitant successful treatment of the periapical implant pathology and the adjacent natural tooth without the removal of the implant. The presence of large bony defect at the apical region of the natural tooth and the implant, resulting in a sinus tract and a deep periodontal pocket, was also confirmed with computerized tomography. The treatment procedure included root canal treatment followed by the debridement of the apical bone lesion, and guided bone regeneration. An uneventful healing with acceptable esthetic was observed.

Calculus-like deposit on the apical external root surface of teeth with post-treatment apical periodontitis: report of two cases

AIM

To report two cases in which calculus-like material was found on external root surfaces of (i) an extracted root and (ii) an apicected part of a root, both of which were removed due to post-treatment refractory apical periodontitis.

SUMMARY

In each case, there was a fistulous tract, which did not heal after conventional root canal treatment. The first case did not heal even after apical surgery, and subsequent tooth extraction revealed calculus-like material on a root surface of complex anatomy. The second case showed radiographic signs of healing after apicectomy. Histology of the apical biopsy revealed a calculus-like material on the external surface of the root apex. It is suggested that the presence of calculus on the root surfaces of teeth with periapical lesions may contribute towards the aetiology of failure.

KEY LEARNING POINTS

Biofilm on the external root surface has been implicated in the failure of apical periodontitis to heal, despite adequate root canal treatment. Calculus-like material was found, in two cases, on the root surface of teeth with post-treatment apical periodontitis, where the only communication externally was a sinus tract.

Levels of evidence for the outcome of endodontic surgery

The purpose of this investigation was twofold: (1) to search for clinical articles pertaining to success and failure of periapical surgery and (2) to assign levels of evidence to these studies except case reports. Electronic and manual searches were conducted to identify all the literature regarding success and failure of periapical surgery since 1970. Articles were reviewed, and each article was assigned to a level of evidence from 1 (highest level) to 5 (lowest level). This search located 79 clinical studies. Among these studies, there were no level of evidence-1 randomized clinical trial studies. Five of the seven level of evidence-2 randomized clinical trials compared postoperative pain between surgical and nonsurgical retreatment. Only two level of evidence-2 randomized clinical trials compared the outcomes of surgical treatment with that of nonsurgical treatment. The majority of frequently quoted "success and failure" studies were case series (level of evidence 4).

The role of preoperative prophylactic antibiotic administration in periapical endodontic surgery: a randomized, prospective double-blind placebo-controlled study

AIM

To determine the value of clindamycin prophylaxis in the prevention of postoperative wound infections in patients undergoing endodontic surgery.

METHODOLOGY

This study included 256 patients undergoing endodontic surgery in a prospective double-blind placebo-controlled trial comparing oral administration of an oral placebo versus a preoperative 600 mg dose of clindamycin. After randomization the study medication was administered orally 1 h before surgery in a double-blind fashion. For a period of 4 weeks the postoperative course was observed according to clinical parameters of infection. Primary end-point was infection at the surgical site.

RESULTS

The mean age of the study population was 44.4 years (SD 11.4, range 18-82 years) with a sex distribution of 147 females (47.4%) and 109 males (42.6%). Mean age of the patients in the clindamycin group was 44.7 years (SD 12.0), and the mean age in the placebo group was 44.1 years (SD 10.8) (P = 0.49). In the clindamycin group, the mean duration of surgery was 32.3 min (SD 8.8) and in the placebo group the mean duration of surgery was 32.5 min (SD 8.4) (P = 0.89). Two infections [1.6%; 95 confidence interval (CI): 0.48-4.72] were identified in the clindamycin group and four (3.2%; 95 CI: 0.42-1.33) in the placebo group (P = 0.448).

CONCLUSIONS

No statistically significant difference was found between clindamycin prophylaxis and placebo with regard to the prevention of postoperative infection in endodontic surgical procedures.

Endodontic procedures for retreatment of periapical lesions

BACKGROUND

When primary root canal therapy fails, periapical lesions can be retreated with or without surgery. Root canal retreatment is a non-surgical procedure that involves removal of root canal filling materials from the tooth, followed by cleaning, shaping and obturating of the canals. Root-end resection is a surgical procedure that involves exposure of the periapical lesion through an osteotomy, surgical removal of the lesion, removal of part of the root-end tip, disinfection and, commonly, retrograde sealing or filling of the apical portion of the remaining root canal. This review updates one published in 2008.

OBJECTIVES

To assess effects of surgical and non-surgical therapy for retreatment of teeth with apical periodontitis.To assess effects of surgical root-end resection under various conditions, for example, when different materials, devices or techniques are used.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Trials Register (to 10 February 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 1), MEDLINE Ovid (1946 to 10 February 2016) and Embase Ovid (1980 to 10 February 2016). We searched the US National Registry of Clinical Trials (ClinicalTrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials (to 10 February 2016). We placed no restrictions regarding language and publication date. We handsearched the reference lists of the studies retrieved and key journals in the field of endodontics.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) involving people with periapical pathosis. Studies could compare surgery versus non-surgical treatment or could compare different types of surgery. Outcome measures were healing of the periapical lesion assessed after one-year follow-up or longer; postoperative pain and discomfort; and adverse effects such as tooth loss, mobility, soft tissue recession, abscess, infection, neurological damage or loss of root sealing material evaluated through radiographs.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from included studies and assessed their risk of bias. We contacted study authors to obtain missing information. We combined results of trials assessing comparable outcomes using the fixed-effect model, with risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, and 95% confidence intervals (CIs). We used generic inverse variance for split-mouth studies.

MAIN RESULTS

We included 20 RCTs. Two trials at high risk of bias assessed surgery versus a non-surgical approach: root-end resection with root-end filling versus root canal retreatment. The other 18 trials evaluated different surgical protocols: cone beam computed tomography (CBCT) versus periapical radiography for preoperative assessment (one study at high risk of bias); antibiotic prophylaxis versus placebo (one study at unclear risk); different magnification devices (loupes, surgical microscope, endoscope) (two studies at high risk); types of incision (papilla base incision, sulcular incision) (one study at high risk and one at unclear risk); ultrasonic devices versus handpiece burs (one study at high risk); types of root-end filling material (glass ionomer cement, amalgam, intermediate restorative material (IRM), mineral trioxide aggregate (MTA), gutta-percha (GP), super-ethoxy benzoic acid (EBA)) (five studies at high risk of bias, one at unclear risk and one at low risk); grafting versus no grafting (three studies at high risk and one at unclear risk); and low energy level laser therapy versus placebo (irradiation without laser activation) versus control (no use of the laser device) (one study at high risk).There was no clear evidence of superiority of the surgical or non-surgical approach for healing at one-year follow-up (RR 1.15, 95% CI 0.97 to 1.35; two RCTs, 126 participants) or at four- or 10-year follow-up (one RCT, 82 to 95 participants), although the evidence is very low quality. More participants in the surgically treated group reported pain in the first week after treatment (RR 3.34, 95% CI 2.05 to 5.43; one RCT, 87 participants; low quality evidence).In terms of surgical protocols, there was some inconclusive evidence that ultrasonic devices for root-end preparation may improve healing one year after retreatment, when compared with the traditional bur (RR 1.14, 95% CI 1.00 to 1.30; one RCT, 290 participants; low quality evidence).There was evidence of better healing when root-ends were filled with MTA than when they were treated by smoothing of orthograde GP root filling, after one-year follow-up (RR 1.60, 95% CI 1.14 to 2.24; one RCT, 46 participants; low quality evidence).There was no evidence that using CBCT rather than radiography for preoperative evaluation was advantageous for healing (RR 1.02, 95% CI 0.70 to 1.47; one RCT, 39 participants; very low quality evidence), nor that any magnification device affected healing more than any other (loupes versus endoscope at one year: RR 1.05, 95% CI 0.92 to 1.20; microscope versus endoscope at two years: RR 1.01, 95% CI 0.89 to 1.15; one RCT, 70 participants, low quality evidence).There was no evidence that antibiotic prophylaxis reduced incidence of postoperative infection (RR 0.49, 95% CI 0.09 to 2.64; one RCT, 250 participants; low quality evidence).There was some evidence that using a papilla base incision (PBI) may be beneficial for preservation of the interdental papilla compared with complete papilla mobilisation (one RCT (split-mouth), 12 participants/24 sites; very low quality evidence). There was no evidence of less pain in the PBI group at day 1 post surgery (one RCT, 38 participants; very low quality evidence).There was evidence that adjunctive use of a gel of plasma rich in growth factors reduced postoperative pain compared with no grafting (measured on visual analogue scale: one day postoperative MD -51.60 mm, 95% CI -63.43 to -39.77; one RCT, 36 participants; low quality evidence).There was no evidence that use of low energy level laser therapy (LLLT) prevented postoperative pain (very low quality evidence).

AUTHORS' CONCLUSIONS

Available evidence does not provide clinicians with reliable guidelines for treating periapical lesions. Further research is necessary to understand the effects of surgical versus non-surgical approaches, and to determine which surgical procedures provide the best results for periapical lesion healing and postoperative quality of life. Future studies should use standardised techniques and success criteria, precisely defined outcomes and the participant as the unit of analysis.

Periradicular curettage

Periradicular curettage is a part of the treatment procedure of periradicular surgery. Its main purpose is to remove pathological periradicular tissues for visibility and accessibility to facilitate the treatment of the apical root canal system, or sometimes for the removal of harmful foreign materials present in the periradicular area. Inflammatory periradicular lesions (granuloma and cysts) are the responses of the periradicular tissues to irritants from the root canal and not from the periradicular area unless medicaments and/or filling materials have been forced through the apical foramina or perforations into the periodontium. Histologically, the inflammatory periradicular lesion is similar to healing granulation tissue, which is composed of cells which have natural and specific immunological defence capability and cooperate by means of cytokines to amplify the protective mechanisms of the host. Accordingly, it is not necessary to completely curette out all the inflamed periradicular tissues during surgery, since this granulation-like tissue will be incorporated into the new granulation tissue as part of the healing process. To control the source of irritants in the root canal is far more important than to remove all periradicular tissues affected by the irritants. The successful removal of all irritants from the root canal system results in resolution of pulpally induced periradicular lesions. In the case where the periradicular lesion is caused by endodontic instruments or cytotoxic filling materials placed in the periradicular tissues, removal of these foreign objects is required for resolution of the lesion.

Periapical microsurgery: the effect of root dentinal defects on short- and long-term outcome

INTRODUCTION

The purpose of this prospective clinical study was to evaluate the clinical outcome of endodontic microsurgery on roots exhibiting the presence or absence of dentinal defects at 1-year and 3-year follow-up period.

METHODS

One hundred fifty-five teeth were treated with periapical microsurgery using a modern microsurgical protocol in a private practice setting. The root apices were resected and inspected for dentinal defects with a surgical operating microscope and a 0.8-mm head diameter light-emitting diode microscope diagnostic probe light. After inspection, root-end preparations were performed using ultrasonic tips, and root-end fillings were placed. Follow-up visits occurred at 1 year and 3 years postoperatively. The primary outcome measure used was the change in the radiographic apical bone density, and the secondary outcome measure used was the absence of clinical symptoms.

RESULTS

Of the 155 treated teeth, a total of 134 teeth were assessed at the 1-year follow-up and 127 teeth at the 3-year evaluation. In the "intact" group, 94.8% healed at 1 year, and 97.3% healed at 3 years. In the "dentinal defect" group, 29.8% healed at 1 year, and 31.5% healed at 3 years. The baseline root condition of either "dentinal defect" or "intact" showed a statistical difference in the healing outcome at both 1 and 3 years.

CONCLUSIONS

This prospective periapical microsurgery study showed a significant superior clinical outcome for intact roots when compared with roots with dentinal defects at both 1 year and at 3 years postoperatively.

Survival of surgical endodontic treatment performed in a dental teaching hospital: a cohort study

AIM

To assess the survival function of surgical endodontic treatment performed at least 1 year before in a dental teaching hospital.

METHODOLOGY

A total of 194 teeth surgically treated between 1991 and 2001 were recalled and examined clinically and radiographically using a set of strict criteria. The Kaplan-Meier method and log rank test were used to evaluate the survival time. Confounding factors were examined by Cox regression analysis.

RESULTS

The median survival time of the 154 first-time surgically treated teeth was 92.1 months (95% CI: 40.9-143.4) and that of the 40 resurgery cases was 39.1 months (95% CI: 6.1-72.1) up to the date of recall. There was a significant difference in the length of survival between the two groups. For those first-time surgery cases, the preoperative marginal bone loss and the operator had a significant influence on the survival time (P < 0.05).

CONCLUSIONS

The survival of surgical endodontic treatment declined nonlinearly with time. The preoperative marginal bone loss, operator and resurgery were important factors affecting the survival of this treatment modality.

Reperfusion of autotransplanted teeth--comparison of clinical measurements by means of dental magnetic resonance imaging

OBJECTIVE

Dental magnetic resonance imaging (dMRI) with administration of contrast material is one method of assessing pulpal perfusion. The purpose of this study was to evaluate the level of contrast enhancement displayed by means of dMRI after transplantation of teeth and to compare these findings with the results of tooth mobility, pocket depth, cold, and electrical tests.

STUDY DESIGN

Twenty-three teeth with either complete root formation or incomplete root formation (IRF) were investigated by using dMRI and were clinically examined at intervals of 2, 4, 8, and 12 weeks, as well as 6 months and 12 months after transplantation.

RESULTS

An analysis of the enhancement in the dental images revealed a significant difference between teeth with IRF and teeth with complete root formation. In addition, the time to occurrence of a positive reaction to the cold test was significantly longer for teeth with IRF.

CONCLUSIONS

The findings of this study indicate that transplanted IRF teeth are associated with reperfusion seen by means of dMRI as well as with delayed occurrence of a positive cold test.