ASSOCIATION BETWEEN INTRA-RADICULAR POSTS AND PERIAPICAL LESIONS IN ENDODONTICALLY TREATED TEETH

Introduction:

A significant number of endodontically treated teeth restored with posts have associated periapical lesions, and several authors have discussed the probable causes of the development of these. Attention has been focused on restorative procedures performed after endodontic treatment and their association with the prognosis of endodontic therapy because a number of root-filled teeth will require post- and core-retained restorations.

Purpose:

The purpose of this study was to evaluate, by examination of periapical radiographs, whether the placement of intra-radicular posts in endodontically treated teeth may act as a risk factor for development of periapical lesions.

Material and Methods:

This case-control study analyzed periapical radiographs of 72 endodontically treated teeth with coronal restorations. All radiographs were obtained from a single private practice. Specimens were assigned to 2 groups: Group 1 (control) was composed of teeth without periapical lesions and Group 2 (case) was composed of teeth with periapical lesions. The number of teeth with and without posts in each group was recorded. Three calibrated examiners analyzed the radiographs visually under X4 magnification.

Results:

In Group 1, 28 (65.1%) out of 43 teeth were restored with posts. In Group 2, 24 (82.8%) out of 29 teeth had intra-radicular posts. The interpretation of chi-square test showed that these percentages were not significantly different (x²=2.687; p=0.101). Odds ratio was 2.571 (0.8158.118), which indicates that there was no statistically significant association between periapical lesions and posts.

Conclusion:

Intra-radicular posts placed in endodontically treated teeth were not a significant risk factor for development of periapical lesions in the practice where the cohort of patients was treated.     

EFFECTIVENESS OF NaOCl ALONE OR IN COMBINATION WITH EDTA ON THE DIFFUSION OF HYDROXYL IONS RELEASED BY CALCIUM HYDROXIDE PASTE

Aim:

To evaluate the effect of different irrigant solutions employed during removal and replacement of calcium hydroxide paste on the diffusion of hydroxyl ions through root canal dentine in vitro.

Methodology:

Thirty-five maxillary and mandibular human canines with straight and fully developed roots were used. After mechanical preparation up to 1mm short of tooth length, 30 canals were filled with calcium hydroxide paste and 5 canals were left empty; all teeth had their coronal accesses properly sealed. Teeth were placed in plastic containers with distilled water, and pH was read after 30 days when the paste from 20 teeth was renewed. After removal of the paste by endodontic instrumentation and irrigation with distilled water, canals were replenished with newly mixed paste in Group 1 and 2. In these groups, final irrigation was conducted with 5 mL of EDTA followed by 5 mL of NaOCl in specimens in Group 1, and 5 mL of NaOCl only in specimens in Group 2. In 10 teeth the paste was not replenished at 30 days (Group 3). All specimens were returned to the containers with fresh distilled water, and the pH was recorded after another 30 days. The differences between the first (30d) and second (60d) pH readings were calculated and submitted to analysis of variance and individual comparisons using the Scheffeé''s test.

Results:

Results of mean analysis on differences of pH readings showed that greater diffusion had occurred on specimens in Group 3. Individual comparisons using Scheffeé''s test showed statistical significance between Groups 2 and 3, and equivalence between all other groups.

Conclusion:

It was concluded that the use of EDTA did not enhance diffusion of hydroxyl ions through root canal dentine.     

HISTOMICROBIOLOGIC ASPECTS OF THE ROOT CANAL SYSTEM AND PERIAPICAL LESIONS IN DOGS' TEETH AFTER ROTARY INSTRUMENTATION AND INTRACANAL DRESSING WITH Ca(OH)2 PASTES

OBJECTIVE:

The purpose of this study was to evaluate the distribution of microorganisms in the root canal system (RCS) and periapical lesions of dogs'' teeth after rotary instrumentation and placement of different calcium hydroxide [Ca(OHy-based intracanal dressings.

MATERIALS AND METHODS:

Chronic periapical lesions were experimentally induced in 80 premolar roots of four dogs. Instrumentation was undertaken using the ProFile rotary system and irrigation with 5.25% sodium hypochlorite. The following Ca(OH)₂-based pastes were applied for 21 days: group 1 - Calen (n=18); group 2 - Calen+CPMC (n=20); group 3 - Ca(OH₂ p.a. + anaesthetic solution (n=16) and group 4 - Ca(OH₂ p.a.+ 2% chlorhexidine digluconate (n=18). Eight root canals without endodontic treatment constituted the control group. Histological sections were obtained and stained with Brown & Brenn staining technique to evaluate the presence of microorganisms in the main root canal, ramifications of the apical delta and secondary canals, apical cementoplasts, dentinal tubules, areas of cemental resorption and periapical lesions. The results were analyzed statistically by the Mann-Whitney U test (p<0.05).

RESULTS:

The control group showed the highest prevalence of microorganisms in all sites evaluated. Gram-positive cocci, bacilli and filaments were the most frequent morphotypes. Similar microbial distribution patterns in the RCS and areas of cementum resorption were observed in all groups (p>0.05). The percentage of RCS sites containing microorganisms in groups 1, 2, 3, 4 and control were: 67.6%, 62.5%, 78.2%, 62.0% and 87.6%, respectively.

CONCLUSION:

In conclusion, the histomicrobiological analysis showed that the rotary instrumentation and the different calcium hydroxide pastes employed did not effectively eliminate the infection from the RCS and periapical lesions. However, several bacteria seen in the histological sections were probably dead or were inactivated by the biomechanical preparation and calcium hydroxide-based intracanal dressing.     

INFLUENCE OF SMEAR LAYER REMOVAL ON THE OBTURATION OF ROOT CANAL RAMIFICATIONS

Objective:

This study evaluated whether smear layer removal has any influence on the filling of the root canal system, by examining the obturation of lateral canals, secondary canals and apical deltas.

Material and Methods:

Eighty maxillary and mandibular canines were randomly divided into two groups, according to their irrigation regimen. Both groups were irrigated with 1% NaOCl during canal shaping, but only the teeth in Group II received a final irrigation with 17% EDTA for smear layer removal. The root canals were obturated with lateral condensation of gutta-percha and the specimens were cleared, allowing for observation under the microscope.

Results:

In Groups I and II, 42.5% and 37.5% of the teeth, respectively, presented at least one filled canal ramification. Although a larger number of obturated ramifications was found in Group I, there were no statistically significant differences between the two groups (p = 0.4957).

Conclusion:

Smear layer removal under the conditions tested in this study did not affect the obturation of root canal ramifications when lateral condensation of gutta-percha was the technique used for root canal filling.     

Evaluation of technical quality and periapical health of root-filled teeth by using cone-beam CT

Objective

This study aimed to assess the quality of root fillings, coronal restorations, complications of all root-filled teeth and their association with apical periodontitis (AP) detected by cone-beam computed tomography (CBCT) images from an adult Turkish subpopulation.

Material and Methods

The sample for this study consisted of 242 patients (aging from 15 to 72 years) with 522 endodontically treated teeth that were assessed for technical quality of the root canal filling and periapical status of the teeth. Additionally, the apical status of each root-filled tooth was assessed according to the gender, dental arch, tooth type and age classification, undetected canals, instrument fracture, root fracture, apical resorption, apical lesion, furcation lesion and type and quality of the coronal structure. Statistical analysis was performed using percentages and chi-square test.

Results

The success rate of the root canal treatment was of 54.4%. The success rates of adequate and inadequate root canal treatment were not significantly different (p>0.05). Apical periodontitis was found in 228 (45.6%) teeth treated for root canals. Higher prevalence of AP was found in patients aging from 20 to 29 years [64 (27%) teeth] and in anterior (canines and incisors) teeth [97 (41%) teeth].

Conclusions

The technical quality of root canal filling performed by dental practitioners in a Turkish subpopulation was consistent with a high prevalence of AP. The probable reasons for this failure are multifactorial, and there may be a need for improved undergraduate education and postgraduate courses to improve the clinical skills of dental practitioners in endodontics.     

Mesiodistal root angulation of permanent teeth in children with mixed dentition and normal occlusion

Objective

There is little information regarding the mesiodistal angulation of permanent teeth in mixed dentition. The aim of this study was to evaluate mesiodistal root angulation of permanent incisors, canines and first molars of 100 Brazilian children, using a new horizontal reference plane based on the midpoint of the intercuspation of primary canines and permanent first molars in panoramic radiographs during the mixed-dentition phase.

Material and methods

Children were equally divided between the genders with a mean age of 8.9 years (SD=0.76), normal occlusion and no eruptive disturbances.

Results

The angulation of the permanent maxillary first molars was close to the vertical, whereas the mandibular molars presented approximately 25 degrees of distal root angulation. The maxillary canines were the most distally angulated teeth, whereas the permanent mandibular canines were vertically positioned. The evaluation of the anterior maxillary area showed vertical position of permanent lateral, and central incisors with a slight distal angulation, whereas the permanent mandibular incisors tended to a mesial radicular convergence.

Conclusions

The proposed reference line could be useful in mixed dentition root angulation evaluation; there was a slight asymmetry in the mesiodistal angulation among homologous teeth, and also a small variation between the male and the female groups, but no difference between 8-and 10-year-old children.     

Effect of MTA-based sealer on the healing of periapical lesions

Some manufacturers have recently added specific components to improve the ease of handling and insertion material properties of MTA in order to create MTA-based sealers.

Objective:

The aim of this study was to evaluate the healing of periapical lesions in canine teeth after a single session of endodontic treatment with MTA Fillapex^® compared with Sealapex or Endo-CPM-Sealer^®.

Material and Methods:

Sixty-two root canals were performed on two 1-year-old male dogs. After coronal access and pulp extirpation, the canals were exposed to the oral cavity for 6 months in order to induce periapical lesions. The root canals were prepared, irrigated with a solution of 2.5% sodium hypochlorite and filled with gutta-percha and different sealers, according to the following groups: 1) Sealapex; 2) Endo-CPM-Sealer^®; and 3) MTA Fillapex. Some teeth with periapical lesions were left untreated for use as positive controls. Healthy teeth were used as negative controls. After 6 months, the animals were sacrificed and serial sections from the roots were prepared for histomorphologic analysis and stained with hematoxylin and eosin and the Brown and Brenn technique. The lesions were scored according to pre-established histomorphologic parameters and the scores statistically analyzed using the Kruskal-Wallis test.

Results:

All 3 materials produced similar patterns of healing (p>0.05); in particular, persistent inflammation and absence of complete periapical tissue healing were consistently noted.

Conclusions:

Preparation of the infected root canals followed by filling with the materials studied was insufficient to provide complete healing of the periapical tissues.     

FRACTURE RESISTANCE AND FAILURE PATTERN OF TEETH SUBMITTED TO INTERNAL BLEACHING WITH 37% CARBAMIDE PEROXIDE,WITH APPLICATION OF DIFFERENT RESTORATIVE PROCEDURES

Objective.

This study investigated the compressive fracture strength and failure pattern in premolars submitted to endodontic treatment and internal bleaching with 37% carbamide peroxide for 21 days, with application of different restorative procedures.

Material and methods.

Six groups were employed (n = 10): 1) non-bleached teeth and pulp chamber sealed with IRM; 2) bleached teeth and pulp chamber sealed with IRM; 3) bleached teeth and pulp chamber filled with light cured composite resin; 4) bleached teeth, root canals prepared at 10mm, filling of the root canal and pulp chamber with IRM; 5) bleached teeth, root canals prepared at 10mm, luting of prefabricated metallic post with zinc phosphate and pulp chamber sealed with composite resin; 6) bleached teeth, root canals prepared at 10mm, luting of glass fiber post with resin cement and pulp chamber sealed with composite resin. After 24-hour storage in distilled water, the specimens were submitted to compressive fracture strength testing in a universal testing machine.

Results.

The following values were found: Group 1 – 56.23kgf; Group 2 – 48.96kgf; Group 3 – 53.99kgf; Group 4 – 45.72kgf; Group 5 – 54.22kgf; Group 6 – 60.12kgf. The analysis of variance did not reveal statistically significant difference between groups (p<0.05), suggesting that internal bleaching with 37% carbamide peroxide did not weaken the dental tissues. The largest number of unfavorable fractures was observed for Groups 2 (50%), 4 (40%), and 5 (30%). Group 6 exhibited the most favorable failure pattern.

Conclusions.

The results suggest that internal bleaching with 37% carbamide peroxide did not significantly weaken the teeth. Among the bleached teeth, those with temporary IRM restorations or metallic posts demonstrated the most unfavorable fracture pattern, whereas the most favorable fracture pattern occurred in teeth restored with composite resin and glass fiber posts.     

Detection of Bacterial Flora in Orofacial Space Infections and Their Antibiotic Sensitivity Profile

Introduction

Most odontogenic infections arise as a sequel of pulp necrosis caused by caries, trauma, periodontitis, etc. They range from periapical abscesses to superficial and deep infections in neck. Some resolve with little consequence and some lead to severe infections of head and neck region. The purpose of this study was to identify microbial flora present in orofacial space infection of odontogenic origin and thereby provide better perspective in management of odontogenic infection.

Materials and Methods

Twenty-six patients with space infection of odontogenic origin were selected irrespective of their age and gender. Pus samples were collected and processed in the microbiology laboratory for the growth of anaerobic and aerobic bacteria and antibiotic sensitivity profile.

Results

Demographic profile of the patients showed that male patients were more commonly involved and most patients fell in to the third and fourth decade of age groups. Most common site of involvement was submandibular space. Alpha hemolytic streptococci were the frequent aerobic bacterial isolate and among anaerobes, anaerobic streptococci followed by bacteroids were the major pathogens. Clindamycin, Gentamycin, Linezolid, Imipenam were the most effective antibiotics. 20 % of the aerobes were resistant to penicillin.

Conclusion

Streptococcus species are still the commonest pathogen in orofacial infections of odontogenic origin. Administration of amoxicillin clavulanic acid combination and metronidazole followed by surgical drainage of abscess and extraction of infected teeth, yielded satisfactory resolution of infection.     

COMPARISON OF THE FRACTURE RESISTANCE OF ENDODONTICALLY TREATED TEETH RESTORED WITH PREFABRICATED POSTS AND COMPOSITE RESIN CORES WITH DIFFERENT POST LENGTHS

Objective:

This study evaluated the fracture strengths of endodontically treated teeth restored with prefabricated posts with different post lengths.

Material and methods:

Thirty freshly extracted canines were endodontically treated. They were randomly divided into groups of 10 teeth and prepared according to 3 experimental protocols, as follows; Group 1/3 PP: teeth restored with prefabricated post and composite resin core (Z250) with post length of 5.0mm; Group 1/2 PP and Group 2/3 PP: teeth restored with prefabricated post and composite resin core (Z250) with different combinations of post length of 7.5mm and 10mm, respectively. All teeth were restored with full metal crowns. The fracture resistance (N) was measured in a universal testing machine (crosshead speed 0.5mm/min) at 45 degrees to the tooth long axis until failure. Data were analyzed by one-way analysis of variance (α=.05).

Results:

The one-way analysis of variance demonstrated no significant difference among the different post lengths (P>.05) (Groups 1/3 PP = 405.4 N, 1/2 PP = 395.6 N, 2/3 PP = 393.8 N). Failures occurred mainly due to core fracture.

Conclusion:

The results of this study showed that an increased post length in teeth restored with prefabricated posts did not significantly increase the fracture resistance of endodontically treated teeth.     

Periapical Status Related to the Quality of Coronal Restorations and Root Fillings in a Korean Population

Introduction

The purpose of this study was to assess the prevalence of apical periodontitis in root canal–treated teeth from the Korean population and to evaluate the relationship between the quality of root canal fillings and coronal restorations and the periapical status of these teeth.

Methods

Full-mouth periapical radiographs at the Dental Hospital of Yonsei University, Seoul, South Korea, were examined. A total of 1030 endodontically treated teeth restored with full veneer crown–type restorations were evaluated by 2 independent examiners. Teeth were classified as healthy or diseased according to the periapical status. The quality of endodontic treatment and coronal restorations were also classified via radiographic and clinical evaluation. The data were analyzed using the chi-square test and logistic regression.

Results

Forty-one percent of all endodontically treated teeth were classified as diseased. Approximately 35.6% of the teeth had endodontic treatments that were rated as adequate. The diseased teeth rate for cases with adequate endodontic treatment was 24.5%, which was significantly lower when compared with teeth with inadequate endodontic treatment (49.9%). The number of teeth with adequate coronal restorations was 706 (68.5%). Teeth with adequate coronal restorations had a significantly decreased prevalence of diseased teeth (34.7%) compared with teeth with inadequate coronal restorations (54.3%). Teeth with both adequate root fillings and restorations showed a significantly better outcome (82.3%) than the others, and teeth with both inadequate root fillings and restorations showed a significantly worse outcome (41.2%) than the others.

Conclusions

Data from this Korean population showed a relatively high prevalence of apical periodontitis. The quality of endodontic treatment and coronal restorations were of equal importance and were strong independent predictors of the periapical status.     

Interference of partial visual analysis of root filling quality and apical status on retreatment decisions

Objective

The presence of periapical radiolucency has been used as a criterion for endodontic treatment failure. However, in addition to the inherent limitations of radiographic examinations, radiographic interpretations are extremely subjective. Thus, this study investigated the effect of partial analysis of root filling quality and periapical status on retreatment decisions by general dentists.

Material and Methods

Twelve digitalized periapical radiographs were analyzed by 10 observers. The study was conducted at three time points at 1-week intervals. Radiographs edited with the Adobe Photoshop CS4 software were analyzed at three time points: first, only root filling quality was analyzed; second, only the periapical areas of the teeth under study were visualized; finally, observers analyzed the unedited radiographic image. Spearman''s coefficient was used to analyze the correlations between the scores assigned when the periapical area was not visible and when the unedited radiograph was analyzed, as well as between the scores assigned when root fillings where not visible and when the unedited radiograph was analyzed. Sensitivity, specificity, positive and negative predictive values between partial images and unedited radiographs were also used to analyze retreatment decisions. The level of significance was set at 5%.

Results

The visualization of the root filling on the unedited radiograph affected the interpretation of the periapical status and the technical quality of the fillings has a greater influence on the general dentist''s decision to prescribe endodontic retreatment than the periapical condition.

Conclusion

In order to make endodontic diagnosis, radiographic interpretation process should not only emphasize technical aspects, but also consider biological factors.     

IN VITRO STUDY OF THE EFFECT OF ER:YAG LASER IRRADIATION ON THE APICAL SEALING OF DIFFERENT ROOT CANAL SEALERS

Objectives:

The aim of this study was to determine the effect of Er:YAG laser irradiation used to clean dentinal walls on the apical sealing of root canals filled with different types of sealers.

Background Data:

Laser application to the dentinal walls removed debris, rendering the root canals free of smear layers and leaving the dentinal canaliculi open.

Methods:

Sixty-four maxillary canines obtained from laboratory files were instrumented with K-files (Dentsply, Maillefer, Ballaigues, Switzerland) using the crown-down technique, and irrigated with a 0.5% sodium hypochlorite solution. The specimens were divided into two groups of 32 teeth each. In group I, the teeth were instrumented and irrigated with sodium hypochlorite solution, and divided into four subgroups to be sealed with the different materials (Endofill, N-Rickert, Sealapex and Sealer 26). In group II, the root canals were subjected to Er:YAG laser irradiation (200 mJ, 7 Hz and 60 J total energy), followed by root canal sealing as in group I.

Results:

The data showed lower levels of apical microleakage in the teeth filled with N-Rickert, Sealapex and Sealer 26 cements than in those sealed with Endofill (p < 0.01). No significant difference in microleakage was observed between teeth irrigated only with 0.5% sodium hypochlorite and those submitted to Er:YAG laser application (p > 0.05).

Conclusions:

The Er:YAG laser irradiation applied to the root canal walls was not able to prevent apical microleakage.     

A QUANTITATIVE ANALYSIS OF ROTARY,ULTRASONIC AND MANUAL TECHNIQUES TO TREAT PROXIMALLY FLATTENED ROOT CANALS

Objective:

The efficiency of rotary, manual and ultrasonic root canal instrumentation techniques was investigated in proximally flattened root canals.

Material and Methods:

Forty human mandibular left and right central incisors, lateral incisors and premolars were used. The pulp tissue was removed and the root canals were filled with red die. Teeth were instrumented using three techniques: (i) K3 and ProTaper rotary systems; (ii) ultrasonic crown-down technique; and (iii) progressive manual technique. Roots were bisected longitudinally in a buccolingual direction. The instrumented canal walls were digitally captured and the images obtained were analyzed using the Sigma Scan software. Canal walls were evaluated for total canal wall area versus noninstrumented area on which dye remained.

Results:

No statistically significant difference was found between the instrumentation techniques studied (p<0.05).

Conclusion:

The findings of this study showed that no instrumentation technique was 100% efficient to remove the dye.     

MARGINAL ADAPTATION AND PERFORMANCE OF BIOACTIVE DENTAL RESTORATIVE MATERIALS IN DECIDUOUS AND YOUNG PERMANENT TEETH

Objective:

The aim of this study was to investigate the adaptation of different types of restorations towards deciduous and young permanent teeth.

Materials and Methods:

Class V cavities were prepared in deciduous and young permanent teeth and filled with different materials (a conventional glass-ionomer, a resin-modified glass-ionomer, a poly-acid-modified composite resin and a conventional composite resin). Specimens were aged in artificial saliva for 1, 6, 12 and 18 months, then examined by SEM.

Results:

The composite resin and the polyacid-modified composite had better marginal adaptation than the glass-ionomers, though microcracks developed in the enamel of the tooth. The glass-ionomers showed inferior marginal quality and durability, but no microcracking of the enamel. The margins of the resin-modified glass-ionomer were slightly superior to the conventional glass-ionomer. Conditioning improved the adaptation of the composite resin, but the type of tooth made little or no difference to the performance of the restorative material. All materials were associated with the formation of crystals in the gaps between the filling and the tooth; the quantity and shape of these crystals varied with the material.

Conclusions:

Resin-based materials are generally better at forming sound, durable margins in deciduous and young permanent teeth than cements, but are associated with microcracks in the enamel. All fluoride-releasing materials give rise to crystalline deposits.     

FRACTURE RESISTANCE OF WEAKENED TEETH RESTORED WITH CONDENSABLE RESIN WITH AND WITHOUT CUSP COVERAGE

Objectives:

This in vitro study evaluated the fracture resistance of weakened human premolars (MOD cavity preparation and pulp chamber roof removal) restored with condensable resin composite with and without cusp coverage.

Material and Methods:

Thirty human maxillary premolars were divided into three groups: Group A (control), sound teeth; Group B, wide MOD cavities prepared and the pulp chamber roof removed and restored with resin composite without cusp coverage; Group C, same as Group B with 2.0 mm of buccal and palatal cusps reduced and restored with the same resin. The teeth were included in metal rings with self-curing acrylic resin, stored in water for 24 h and thereafter subjected to a compressive axial load in a universal testing machine at 0.5 mm/min.

Results:

The mean fracture resistance values ± standart deviation (kgf) were: group A: 151.40 ± 55.32, group B: 60.54 ± 12.61, group C: 141.90 ± 30.82. Statistically significant differences were found only between Group B and the other groups (p<0.05). The condensable resin restoration of weakened human premolars with cusp coverage significantly increased the fracture resistance of the teeth as compared to teeth restored without cusp coverage.

Conclusion:

The results showed that cusp coverage with condensable resin might be a safe option for restoring weakened endodontically treated teeth.     

Removal efficiency of propolis paste dressing from the root canal

Objetives

The aim of this study was to investigate through scanning electron microscopy (SEM) the cleaning of root canal walls after the use of experimental propolis or calcium hydroxide root canal dressings.

Material and Methods

Twenty single-rooted teeth were used. After conventional cleaning and shaping procedures and removal of the smear layer with 17% EDTA, the teeth were divided into four groups according to the medication used (N=5): Group I (control) - No drug, Group II - Calcium hydroxide dressing, Group III - Propolis paste A70D and Group IV - Propolis paste D70D. The medications were introduced into the root canals and maintained for 7 days, then removed with a K-file and 5 mL of 1% sodium hypochlorite irrigation. Finally, the canals were flushed with 2 mL of 17% EDTA for 3 min. For SEM analysis, the roots were cleaved and microphotographs from the middle third of the root canal were taken at 750x. The cleaning of the root canal walls was determined by the number of open dentinal tubules as verified with the software Image Tool 3.1. The statistical analysis was performed by ANOVA and Tukey''s test (p<0.05).

Results

The results showed no statistically significant difference between the calcium hydroxide and propolis groups.

Conclusions

The experimental propolis pastes presented acceptable physical characteristics to be used as intracanal medicaments.     

Cone beam computed tomography study of apical root resorption induced by Herbst appliance

Objective

This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT).

Material and Methods

The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years) with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0) and after Herbst treatment (T1). All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates’ correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%.

Results

Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders.

Conclusion

CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance.     

Prognostic factors on periapical surgery: A systematic review

Background

Analyze the most important prognostic factors when performing periapical surgery and compare the success rates of distinct authors.

Introduction

Periapical surgery is an approach to treat non-healing periapical lesions and it should be viewed as an extension of endodontic treatment and not as a separate entity.

Material and Methods

A search of articles published in Cochrane, PubMed (MEDLINE) and Scopus was conducted with the key words “prognostic factors”, “prognosis”, “periapical surgery”, “endodontic surgery” and “surgical endodontic treatment”. The inclusion criteria were articles including at least 10 patients, published in English, for the last 10 years. The exclusion criteria were nonhuman studies and case reports.

Results

33 articles were selected from 321 initially found. Ten articles from 33 were excluded and finally the systematic review included 23 articles: 1 metaanalysis, 1 systematic review, 2 randomized clinical trials, 6 reviews, 12 prospective studies and 1 retrospective study. They were stratified according to their level of scientific evidence using the SORT criteria.

Conclusions

Factors associated with a better outcome of periapical surgery are patients ≤45 years old, upper anterior or premolar teeth, ≤10 sized lesions, non cystic lesions, absence of preoperative signs and symptoms, lesions without periodontal involvement, teeth with an adequate root-filling length, MTA as root-end filling material, uniradicular teeth, absence of perforating lesions, apical resection < 3 mm, teeth not associated to an oroantral fistula and teeth with only one periapical surgery. Key words:Prognostic factors, prognosis, periapical surgery, endodontic surgery and surgical endodontic treatment.     

Cone beam computed tomographic analysis of maxillary premolars and molars to detect the relationship between periapical and marginal bone loss and mucosal thickness of maxillary sinus

Background

This study assessed the relationship between mucosal thickness (MT) of the maxillary sinus and periodontal bone loss (PBL) and periapical condition of related teeth. We also aimed to identify the association between root apices and the inferior wall of the maxillary sinus using Cone beam computed tomography (CBCT).

Material and Methods

In this study, CBCT images of 205 patients with 410 maxillary sinuses were examined, retrospectively. A total of 582 maxillary molars and 587 premolars were observed. The relationship of each root with maxillary sinus and apical lesions of these roots were classified, PBL was examined and the situations of adjacent teeth were estimated. The effect of these conditions on sinus mucosal thickness (MT) was evaluated.

Results

There was a significant correlation between MT of maxillary sinus and both PBL and age (r = 0.52, p=0.000 and r = 0.111, p= 0.002, respectively). The frequency of MT increased as the severity of apical lesion enlarged. A positive correlation was found between MT and degree of PBL and periapical lesions. To reveal the association between MT and pulpoperiapical condition bivariate correlation was done and a significant relationship between the pulpoperiapical condition and MT was found (r = 0.17, p=0.000).

Conclusions

This retrospective study showed that MT of the maxillary sinus was common among patients with PBL and MT was significantly associated with PBL and apical lesions. The relationship of maxillary sinus to adjacent teeth had also positive correlation with MT. CBCT imaging enabled better evaluation of maxillary sinus, posterior teeth and surrounding structures compared to other imaging tools. Key words:Maxillary sinus mucosal thickness, apical periodontitis, periodontal bone loss, CBCT.