Portland cement use in dental root perforations: a long term followup

Root canal and furcal perforations are causes of endodontic therapy failure and different materials that stimulate tissue mineralization have been proposed for perforation treatment. In the first case, a patient presented tooth 46 with unsatisfactory endodontic treatment and a periapical radiographic lesion. A radiolucent area compatible with a perforating internal resorption cavity was found in the mesial root. The granulation tissue was removed, and root canals were prepared. The intracanal medication was composed of calcium hydroxide and the perforation cavity was filled with Portland cement. The 11-year followup showed radiographic repair of the tissue adjacent to the perforation and absence of clinical signs and symptoms or periapical lesion. In the second case, a patient presented with edema on the buccal surface of tooth 46. The examination showed a radiolucent area in the furcation region compatible with an iatrogenic perforation cavity. The mesial root canals were calcified, and only the distal root canal was prepared. The cavity was filled with a calcium hydroxide-based paste and the distal root canal was obturated. In sequence, the perforation cavity was filled with Portland cement. The 9-year followup showed the tooth in masticatory function with radiographic and clinical aspects compatible with normality.

The effect of the angle of instrumentation of the piezoelectric ultrasonic scaler on root surfaces

To evaluate the influence of variations in the working angle of the piezoelectric ultrasonic scaler (PUS) on root surfaces. Material and methods Fifty-five uniradicular bovine teeth were used, of which 25 teeth were used for the analysis of the roughness and root wear, while the remaining 30 teeth were used for the analysis of morphology (MRS) and the attachment of blood components (ABC). The teeth were randomly divided into five groups according to the type of treatment (G1-G5: piezoelectric ultrasonic scaler; G6: manual curette) and to the PUS working angle applied (G1: 0°; G2: 30°; G3: 45°; G4: 60°; G5: 90°). For statistical analysis, the data describing the MRS and ABC were analysed by the Kruskal–Wallis and Dunn's tests, and the data describing the roughness and tooth wear were analysed by anova and Tukey's tests at the significance level of 5%. Results Manual curette (MC) promoted a smoother root surface than the application of the PUS. The PUS used at the angles of 30° and 45° resulted in a high level of ABC that was comparable to that obtained by MC. Additionally, the group in which the PUS was applied at an angle of 45° exhibited less tooth wear than the other groups. Conclusions Changes in the working angle of the PUS influenced the characteristics of root surfaces after instrumentation.

Healing process of dogs' pulpless teeth after apicoectomy and root canal filling at different levels

Dogs' teeth with infected root canals, were submitted to apicoectomy and the root canals were filled flush or 2 mm short. In a third group the canals were left unfilled and only the access openings were closed. One hundred and eighty days after the treatment, the animals were killed and the specimens prepared for histological analysis. Repair was not observed in the teeth with unfilled root canals. The healing observed in the teeth with root canals filled flush was less complete than the healing observed when the root canals were filled 2 mm short.

Effect of root canal status on periodontal healing after surgical injury in dogs.

This study was carried out to observe if the status of the root canal might influence the healing process of surgically prepared experimental periodontal lesions. Forty tooth roots from four dogs were divided into four different groups: a) root canals with vital pulps, b) root canals open to the oral environment, c) root canals infected and filled with zinc oxide eugenol cement, and d) root canals infected and filled with calcium hydroxide. By means of a surgical intervention, a cavity was prepared in the medium portion of the roots. Six months later, the specimens were removed and prepared for histological analysis. The results, which were submitted to statistical analysis, showed that the status of the root canals influenced the healing process of the experimental periodontal lesions. In the groups where the root canals were filled, calcium hydroxide gave the best results. In the group with root canals left open to the oral environment, resorption of the dentin of the experimental cavities, was the most obvious observation. However, it did not prevent the repair process, only slowed it down.

Orthodontic extrusion as treatment option for crown-root fracture: literature review with systematic criteria

To review the literature searching for a consensus for the choice of orthodontic extrusion as treatment for crown-root fracture. An electronic search was performed in the databases PubMed, Cochrane Central Register of Controlled Trials and Scopus and a manual search of the Journal Dental Traumatology. Forty articles were found in PubMed and 38 in Scopus and after removal of duplicate sample 51 contained articles. Of these, 48 were excluded for not having orthodontic treatment, no follow-up or follow-up less than 6 months, or not report the presence of crown-root fracture. In manual search in Dental Traumatology 20 articles were found, but none of them met the prerequisites established. So, three articles formed the basis of the study. The choice of how to treat orthodontic extrusion of crown-root fracture was effective and stable, without root and periodontal changes. Factors, such as root formation and presence of pulp vitality were decisive for determining the stages of treatment, however, there is no consensus based on scientific evidence about these protocols.

Immediate tooth replantation in rats: effect of systemic antibiotic therapy with amoxicillin and tetracycline

The aim of this study was to evaluate the influence of systemic administration of antibiotics (amoxicillin and tetracycline) at the different phases of the repair process (7, 15, 30 days) in immediate rat tooth replantation. Ninety rats had their incisors extracted and stored in saline for 5 min. Next, the teeth were replanted, and the animals were assigned to three groups according to the antibiotic administered by oral gavage: control group, amoxycillin group, and tetracycline group. Euthanasia was performed at 7, 15, and 30 days after replantation. Regardless of the evaluation period, the connective tissue underlying the epithelial attachment and the periodontal ligament showed statistically significant difference relative to the acute inflammatory infiltrate, which was more intense in the control group followed by the tetracycline group. These results point to the fact that systemic antibiotic therapy (SAT) in immediate tooth replantation is beneficial to pulpal and periodontal ligament repair and that amoxycillin is an excellent option. There is a lack of randomized studies assessing how the use of systemic antibiotics could influence tooth healing after immediate replantation.

Delayed tooth replantation in rats: effect of systemic antibiotic therapy with amoxicillin and tetracycline

Systemic antibiotic therapy (SAT) has usually been recommended after tooth replantation, but its actual value has been questioned. As there are no reports in the literature about its influence on tooth replantation, the aim of this study was to evaluate the influence of systemic administration of antibiotics (amoxicillin and tetracycline) at the different phases of the repair process (7, 15, 30 days) in delayed rat tooth replantation. Ninety Wistar rats (Rattus norvegicus albinus) had their maxillary right incisors extracted and bench-dried for 60 min. The dental papilla, enamel organ, pulp tissue, and root surface-adhered periodontal ligament were removed, and the teeth were replanted. The animals received no antibiotics (n = 30) or were medicated systemically with amoxicillin (n = 30) and tetracycline (n = 30), and were euthanized after 7, 15, and 30 days. Regardless of the evaluation period, the acute inflammatory infiltrate was less intense and root resorption presented smaller extent and depth in the group treated with amoxicillin. The results suggest that SAT has a positive influence on the repair process in delayed tooth replantation and that amoxicillin is an excellent treatment option.

Delayed tooth replantation after treatment of necrotic periodontal ligament with citric acid

Objective: to evaluated the effect of treating root-adhered necrotic periodontal ligament (PDL) with citric acid on the healing process in delayed rat tooth replantation. Material and Methods: Forty Wistar rats, assigned to 4 groups (n=10), had their upper right incisor extracted and kept dry on a workbench. For Group I (control), the teeth were replanted after a 5 min extra-alveolar time. For the other groups, replantation was hydroxide-based paste and the teeth were replanted with no root surface treatment. In Group III, the teeth were immersed in citric acid (pH 1) for replanted. In Group IV, instead of the immersion, the roots were scrubbed with gauze soaked in citric acid and the teeth were replanted. The animals difference (p > 0.05) was found among the groups regarding the areas difference (p < 0.05) between the control group and Group IV regarding ankylosis. The control group showed the least replacement resorption percent means compared to the other groups (p < 0.05). The root structure was more affected by replacement resorption and ankylosis in Group IV statistically (p > 0.05). Conclusion: the treatment of root surface-adhered necrotic periodontal ligament with citric acid was not able to prevent the delayed rat tooth replantation.

Multidisciplinary approach for crown-root fracture treatment after trauma: case report

The development of an accurate diagnosis and appropriate treatment plan can be a complex task, especially in cases of dentoalveolar trauma. The authors present a case report of crown-root fracture caused by trauma and highlight the importance of a multidisciplinary approach for the treatment. An eighteen year-old boy had a bicycle accident resulting in dental trauma. The upper right first molar showed a complicated crownroot fracture and the lower left second pre-molar showed an uncomplicated crown-root fracture. Endodontic treatment, controlled tooth extrusion, periodontal surgery for recovery of biological width, and porcelain crown and onlay restorations were performed. Esthetic and functional results were achieved. At the two-year follow-up it was observed that the tooth/onlay interface of the upper right first molar was stained and the onlay of the left lower second pre-molar was fractured. Therefore, the interface stained was repaired and a porcelain crown was made for the lower second premolar. The clinical case presented herein leads to the conclusion that a multidisciplinary treatment plan is extremely important for a proper resolution in cases of dentoalveolar trauma.

Delayed tooth repalantetion after treatment of necrotic periodontal ligament with citric acid

Objective: to evaluated the effect of treating root-adhered necrotic periodontal ligament (PDL) with citric acid on the healing process in delayed rat tooth replantation. Material and Methods: Forty Wistar rats, assigned to 4 groups (n=10), had their upper right incisor extracted and kept dry on a workbench. For Group I (control), the teeth were replanted after a 5 min extra-alveolar time. For the other groups, replantation was done after 60 min. In Group II, the root canals were filled with a calcium hydroxide-based paste and the teeth were replanted with no root surface treatment. In Group III, the teeth were immersed in citric acid (pH 1) for 3 min, the canals were filled with calcium hydroxide and the teeth were replanted. In Group IV, instead of the immersion, the roots were scrubbed with gauze soaked in citric acid and the teeth were replanted. The animals were sacrificed 60 days postoperatively. Results: Regarding replacement resorption, there was statistically significant difference (p < 0.05) between the control group and the other three groups. No statistically significant difference (p > 0.05) was found among the groups regarding the areas of inflammatory resorption. There was also a statistically significant difference (p < 0.05) between the control group and Group IV regarding ankylosis. The control group showed the least replacement resorption percent means compared to the other groups (p < 0.05). The root structure was more affected by replacement resorption and ankylosis in Group IV compared to the Groups II and III, but this difference was not significant statistically (p > 0.05). Conclusion: the treatment of root surface-adhered necrotic periodontal ligament with citric acid was not able to prevent the occurrence of ankylosis, root resorption and inflammatory resorption in delayed rat tooth replantation.

Root reconstructed with mineral trioxide aggregate and guided tissue regeneration in apical surgery: a 5-year follow-up

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Qualitative SEM/EDS analysis of microleakage and apical gap formation of adhesive root-filling materials

Objective: The aim of this study was to compare the correspondence between gap formation and apical microleakage in root canals filled with epoxy resin-based (AH Plus) combined or not with resinous primer or with a dimethacrylate-based root canal sealer (Epiphany). Material and Methods: Thirty-nine lower single-rooted human premolars were filled by the lateral condensation technique (LC) and immersed in a 50-wt% aqueous silver nitrate solution at 37 degrees C (24 h). After longitudinal sectioning, epoxy resin replicas were made from the tooth specimens. Both the replicas and the specimens were prepared for scanning electron microscopy (SEM). The gaps were observed in the replicas. Apical microleakage was detected in the specimens by SEM/energy dispersive spectroscopy (SEM/EDS). The data were analyzed statistically using an Ordinal Logistic Regression model and Analysis of Correspondence (alpha=0.05). Results: Epiphany presented more regions containing gaps between dentin and sealer (p<0.05). There was correspondence between the presence of gaps and microleakage (p<0.05). Microleakage was similar among the root-filling materials (p>0.05). Conclusions: The resinous primer did not improve the sealing ability of AH Plus sealer and the presence of gaps had an effect on apical microleakage for all materials.

Association analysis of clinical aspects and vitamin D receptor gene polymorphism with external apical root resorption in orthodontic patients

Introduction: Vitamin D is responsible for the regulation of certain genes at the transcription level, via interaction with the vitamin D receptor, and influences host immune responses and aspects of bone development, growth, and homeostasis. Our aim was to investigate the association of TaqI vitamin D receptor gene polymorphism with external apical root resorption during orthodontic treatment. Methods: Our subjects were 377 patients with Class II Division 1 malocclusion, divided into 3 groups: (1) 160 with external apical root resorption <= 1.43 mm, (2) 179 with external apical root resorption >1.43 mm), and (3) 38 untreated subjects. External apical root resorption of the maxillary incisors was evaluated on periapical radiographs taken before and after 6 months of treatment. After DNA collection and purification, vitamin D receptor TaqI polymorphism analysis was performed by polymerase chain reaction-restriction fragment length polymorphism. Univariate and multivariate analyses were performed to verify the association of clinical and genetic variables with external apical root resorption (P <0.05). Results: There was a higher proportion of external apical root resorption in orthodontically treated patients compared with the untreated subjects. In patients orthodontically treated, age higher than 14 years old, initial size of the maxillary incisor root superior to 30 mm, and premolar extraction were associated with increased external apical root resorption. Genotypes containing the C allele were weakly associated with protection against external apical root resorption (CC + CT x TT [odds ratio, 0.29; 95% confidence interval, 0.07-1.23; P = 0.091]) when treated orthodontic patients were compared to untreated individuals. Conclusions: Clinical factors and vitamin D receptor TaqI polymorphism were associated with external apical root resorption in orthodontic patients. (Am J Orthod Dentofacial Orthop 2012; 142: 339-47)

Comparative study of cone beam computed tomography and intraoral periapical radiographs in diagnosis of lingual-simulated external root resorptions

Background: Owing to a lack of symptoms and difficult visualization in routine intraoral radiographs, diagnosis of external root resorptions can be challenging. Aim: The goal of this study was to compare two image acquisition methods, intraoral radiographs and cone beam computed tomography (CBCT), in the diagnosis of external resorption. Material and Methods: Thirty-four maxillary and mandibular bicuspids were divided into three groups. Perforations measuring 0.3 and 0.6 mm in diameter and 0.15 and 0.3 mm in depth, respectively, were made on the lingual root surfaces in thirty teeth, and four were used as controls. Next, teeth were mounted on an apparatus and radiographed at mesial, distal, and orthoradial angulations. CBCT images were also taken. The analysis of the intraoral radiographic and tomographic images was carried out by two experts using standardized scores. Data were then compared statistically. Results: A strong agreement between the examiners was observed in both diagnosis methods, the intraoral radiographic (r = 0.93) and the tomographic analysis (r = 1.0). Tomography had higher statistically significant detection values than intraoral radiography (P < 0.05). In intraoral radiographs, the detection was significantly greater (P < 0.05) in the mandibular bicuspids, compared with their maxillary counterparts. The ability to detect 0.6-mm perforations by intraoral radiography was significantly higher than that of 0.3-mm perforations (P < 0.05). Conclusion: Cone beam computed tomography showed better diagnostic ability compared with intraoral radiography, regardless of the tooth or the dimensions of the resorption evaluated.

Experimental model of tooth movement in mice: A standardized protocol for studying bone remodeling under compression and tensile strains

During orthodontic tooth movement (OTM), alveolar bone is resorbed by osteoclasts in compression sites (CS) and is deposited by osteoblasts in tension sites (TS). The aim of this study was to develop a standardized OTM protocol in mice and to investigate the expression of bone resorption and deposition markers in CS and TS. An orthodontic appliance was placed in C57BL6/J mice. To define the ideal orthodontic force, the molars of the mice were subjected to forces of 0.1 N, 0.25 N, 0.35 N and 0.5 N. The expression of mediators that are involved in bone remodeling at CS and TS was analyzed using a Real-Time PCR. The data revealed that a force of 0.35 N promoted optimal OTM and osteoclast recruitment without root resorption. The levels of TNF-alpha, RANKL, MMP13 and OPG were all altered in CS and TS. Whereas TNF-a and Cathepsin K exhibited elevated levels in CS. RUNX2 and OCN levels were higher in TS. Our results suggest that 0.35 N is the ideal force for OTM in mice and has no side effects. Moreover, the expression of bone remodeling markers differed between the compression and the tension areas, potentially explaining the distinct cellular migration and differentiation patterns in each of these sites. (C) 2012 Elsevier Ltd. All rights reserved.