Lesion sterilization and tissue repair with chloramphenicol, tetracyline, zinc oxide/eugenol paste versus conventional pulpectomy: A 36-month randomized controlled trial.

BACKGROUND: Endodontic treatment of primary molars represents one of the challenges in pediatric dentistry. There is a lack of consensus in the literature about the endodontic techniques and filling paste for primary teeth with pulp necrosis. AIM: To compare the effectiveness of the LSTR technique (lesion sterilization and tissue repair) with CTZ paste (chloramphenicol, tetracycline, zinc oxide and eugenol) and pulpectomy with ZOE paste (zinc oxide and eugenol) in the treatment of primary molars with pulp necrosis. DESIGN: Eighty-eight primary molars with pulp necrosis from 70 children between the ages of 3 and 8 years were included. The teeth were randomized to the LSTR with CTZ paste group or pulpectomy with ZOE paste group. Clinical and radiographic evaluations were performed at 18, 24, 30 and 36 months. RESULTS: At 36 months, clinical success was 86.4% in LSTR with CTZ paste and 90.9% in pulpectomy with ZOE paste (p = .45). Radiographic success was 43.2% in both groups (p = 1.00). The overall success was 40.9% in LSTR with CTZ paste and 43.2% in pulpectomy with ZOE paste (p = 1.00). CONCLUSION: After 36 months of evaluation, the effectiveness of the LSTR technique with CTZ paste and pulpectomy with ZOE paste was similar for the treatment of primary molars with pulp necrosis.

LSTR Antibiotic Paste Versus Zinc Oxide and Eugenol Pulpectomy for the Treatment of Primary Molars with Pulp Necrosis: A Randomized Controlled Trial.

Purpose: The purpose of this study was to compare the effectiveness of lesion sterilization and tissue repair (LSTR) antibiotic paste comprised of chloramphenicol, tetracycline, and zinc oxide and eugenol (CTZ) versus zinc oxide eugenol (ZOE) pulpectomy in the treatment of primary molars with pulp necrosis. Methods: A total of 70 three- to eight-year-old subjects with 88 primary mandibular molars with pulp necrosis were included. The teeth were randomized to the CTZ group or ZOE group. The time taken to perform both techniques was recorded. The parents of the children and the dentist who performed clinical evaluations were blind to the group assignment, although the radiographic evaluator could see the difference in treatments. Clinical and radiographic assessments were performed at three, six, nine, and 12 months. Results: At the 12-month evaluation, the clinical success was 86.4 percent for CTZ and 90.9 percent for ZOE (P=0.50), the radiographic success was 75.0 percent for CTZ and 72.7 percent for ZOE (P=0.81), and the overall success was 70.5 percent for CTZ and 72.7 percent for ZOE (P=0.81). The mean time taken to perform was 61.4 (±20.5 standard deviation) minutes for CTZ and 145.1 (±53.2) minutes for ZOE (P<0.001). Conclusions: At 12 months, both techniques presented no significant difference in success rates for nonvital pulp therapy in primary molars with necrosis. The lesion sterilization and tissue repair procedure time using chloramphenicol, tetracycline, zinc oxide, and eugenol was significantly shorter than for a zinc oxide eugenol pulpectomy.

Clinical and radiographic evaluation of Portland cement added to radiopacifying agents in primary molar pulpotomies.

AIM: This was to evaluate the clinical and radiographic outcomes of Portland cement (PC) added to radiopacifying agents in primary molar pulpotomies. METHODS: Thirty primary mandibular molars of children aged between 5 and 9 years were randomly assigned to the following groups: PC; PC with iodoform (PC + CHI(3)); PC with zirconium oxide (PC + ZrO(2)) and treated by pulpotomy technique. Clinical and radiographic follow-up assessments were performed at 6, 12 and 24 months. Statistical analysis was performed by Fisher's exact test (P < 0.05). RESULTS: The clinical and radiographic evaluations showed 100 % success rates, and the results showed no statistically significant difference between groups. CONCLUSIONS: According to this study, PC added to radiopacifying agents exhibited satisfactory clinical and radiographic results in primary molar pulpotomies.

Cicatrización y reparación ápico-periapical en endodoncia / Apical and periapical healing and repair in endodontics

El objetivo de toda preparación endodóntica es eliminar la mayor cantidad de gérmenes, detritus, restos orgánicos y material descompuesto del canal radicular. En este trabajo se presentan casos clínicos con controles a distancia que van de 9 a 33 años, de conductos tratados al mayor ensanche posible, siempre y cuando la estructura radicular lo permita, intentando no perforar, no descentralizar, no hacer escalones, no deformar, y obturando por ténica de condensación lateral a conos múltiples, con cemento sellador a base de óxido de cinc eugenol y conos de gutapercha. Todos fueron éxitos clínicos y radiográficos...

Comparison of the efficacy of nickel-titanium rotary systems with or without the retreatment instruments in the removal of gutta-percha in the apical third.

BACKGROUND: The purpose of this study was to compare the efficacy of nickel-titanium rotary systems with or without the retreatment instruments in the removal of gutta-percha from the apical third. METHODS: The systems compared were as follows: ProTaper Universal (PT), ProTaper Universal Retreatment (PTr), Mtwo (M2) and Mtwo Retreatment (M2r). Sixty extracted mandibular incisors were treated with a crown-down technique and filled with gutta-percha and sealer. The apical diameter was standardized in 0.30 mm, 1 mm from the apex. The teeth were distributed into 4 experimental groups: PT, PTr, M2 and M2r. In PTr and M2r groups, filling materials were removed by PTr/M2r followed by root canals preparation up to a PT F4/M2 40; in groups PT/M2, the filling materials were removed and the root canals were prepared by PT up to a PT F4/M2 up to a M2 40. The roots were split and photomicrographing. The percentage of clean area in the apical 5 mm was calculated using software. Data were analyzed with the Kruskal-Wallis test. RESULTS: Remaining material was found in all hemisections and there was no statistically significant difference between the groups (p = 0.09). Considering the surface of the canal walls of all teeth, the mean of the percentage of clean area was 54%. CONCLUSIONS: Considering the applied methodology, remaining filling material was found in all hemisections, regardless of the retreatment technique and PT or M2 were as effective as PTr/PT or M2r/M2.

Investigation of the effect of sealer use on the heat generated at the external root surface during root canal obturation using warm vertical compaction technique with System B heat source.

INTRODUCTION: During warm vertical compaction of gutta-percha, root canal sealers with different chemical compositions absorb the heat generated inside the root canal. The aim of this research was to assess physicochemical modifications of sealers subjected to the System B heat source (Analytic Technology, Redmond, WA) and to evaluate the effect that the use of different sealers has on the heat transfer to the external root surface. METHODS: Three proprietary brand sealers (AH Plus [Dentsply International, Addlestone, UK], Pulp Canal Sealer [Kerr Corporation, Orange, CA], MTA Fillapex [Angelus Dental Solutions, Londrina, PR, Brazil]) and a prototype sealer based on Portland cement were assessed. The heat generated on the surfaces of System pluggers and the heat dissipation at different levels (apical, midroot, and cervical) over root surface while using different sealers was assessed using thermocouples. Data were collected in 3 different environmental conditions with the tooth suspended in air, immersed in Hank's balanced salt solution, or gelatinized Hank's balanced salt solution. Chemical changes in the sealers induced by the heat were monitored by Fourier transform infrared spectroscopy. The effect of heat changes on the setting time and compressive strength of the sealers was also assessed. RESULTS: The continuous wave plugger sustained a rise in temperature at a maximum of 80°C at the instrument shank. The highest change in temperature on the external root surface was recorded after 1.5 minutes from the start of heating, and it was restored to body temperature by 6 minutes. Environmental conditions affected heat dissipation for all the sealers in the midroot and cervical regions and the highest increase in temperature (∼60°C) recorded in air. In the midroot and cervical regions, the type of sealer used did not affect the rise in temperature. In the apical region, AH Plus obturations resulted in a greater rise in temperature, and the chemical composition of this sealer was affected by high temperature; it also induced a reduction in sealer setting time and strength. CONCLUSIONS: It could be concluded that surrounding conditions, such as temperature and humidity, exerted influence on heating dissipation during the continuous wave of the condensation obturation technique and that root canal sealers presented different conductive/isolating properties. Furthermore, the physical and chemical properties of AH Plus were negatively affected by the changes in temperature.

Histologic study of a human immature permanent premolar with chronic apical abscess after revascularization/revitalization.

INTRODUCTION: Histologic studies of teeth from animal models of revascularization/revitalization are available; however, specimens from human studies are lacking. The nature of tissues formed in the canal of human revascularized/revitalized teeth was not well established. METHODS: An immature mandibular premolar with infected necrotic pulp and a chronic apical abscess was treated with revascularization/revitalization procedures. At both the 18-month and 2-year follow-up visits, radiographic examination showed complete resolution of the periapical lesion, narrowing of the root apex without root lengthening, and minimal thickening of the canal walls. The revascularized/revitalized tooth was removed because of orthodontic treatment and processed for histologic examination. RESULTS: The large canal space of revascularized/revitalized tooth was not empty and filled with fibrous connective tissue. The apical closure was caused by cementum deposition without dentin. Some cementum-like tissue was formed on the canal dentin walls. Inflammatory cells were observed in the coronal and middle third of revascularized/revitalized tissue. CONCLUSIONS: In the present case, the tissue formed in the canal of a human revascularized/revitalized tooth was soft connective tissue similar to that in the periodontal ligament and cementum-like or bone-like hard tissue, which is comparable with the histology observed in the canals of teeth from animal models of revascularization/revitalization.

Clinical and SEM characterization of prolonged retention of a primary tooth with pulpectomy.

Root canal filling with zinc oxide-eugenol (ZOE) paste following primary tooth pulpectomy is a common practice in pediatric dentistry. This material offers high clinical and radiographic success rates. In some cases, however, it is not resorbed along with the root of the primary tooth. The aim of this study was to describe a case of prolonged retention of a primary maxillary incisor that was subjected to pulpectomy and filled with ZOE paste in order to characterize the aspects of root resorption using scanning electron microscopy.

One- versus two-visit endodontic treatment of teeth with apical periodontitis: a histobacteriologic study.

INTRODUCTION: This study analyzed the in vivo microbiological status of the root canal systems of mesial roots of mandibular molars with primary apical periodontitis after 1- or 2-visit endodontic treatment. METHODS: Mesial root canals were instrumented by using either a combination of K3 and LightSpeed instruments (mesiobuccal canals) or the ProTaper system (mesiolingual canals), with 5% NaOCl irrigation. Patency files were used. Smear layer was removed, and a final rinse with 5 mL of 2% chlorhexidine was performed. In the 2-visit group (7 roots, 14 canals), canals were medicated with calcium hydroxide for 1 week and then obturated by using the continuous wave of compaction technique. In the 1-visit group (6 roots, 12 canals), canals were immediately obturated after chemomechanical procedures. Teeth were extracted 1 week after root canal instrumentation and processed for histobacteriologic analysis. RESULTS: In the 1-visit group, no case was completely free of bacteria; residual bacteria occurred in the main root canal (5 of 6 cases), isthmus (5 of 6), apical ramifications (4 of 6), and dentinal tubules (5 of 6). In the 2-visit group, 2 cases were rendered bacteria-free; residual bacteria were found in the main canal only in 2 cases (none of them with persistent dentinal tubule infection), in the isthmus (4 of 7 cases), and in ramifications (2 of 7). The 2 instrumentation techniques performed similarly. When filling material was observed in ramifications, it was usually intermixed with necrotic tissue, debris, and bacteria. CONCLUSIONS: The 2-visit protocol by using an interappointment medication with calcium hydroxide resulted in improved microbiological status of the root canal system when compared with the 1-visit protocol. Residual bacteria were more frequent and abundant in ramifications, isthmuses, and dentinal tubules when root canals were treated without an interappointment medication. Apical ramifications and isthmuses were never completely filled. The use of an antibacterial interappointment agent is necessary to maximize bacterial reduction before filling.

Analysis of root canal treated primary incisor after trauma: two year outcomes.

BACKGROUND: The low number of clinical studies of traumatized teeth submitted to root canal treatment is completely out of proportion to the seriousness that dental trauma imposes on children in early years. AIM: This study evaluates the outcomes of root canal treatment (RCT) in traumatized primary incisors and identifies the predisposing factors associated with therapy success. METHODS: This is a retrospective study conducted with all dental records of 704 patients who had one or more teeth with traumatic injuries. Patients with irreversible pulp changes in primary teeth leading to RCT with a 24 month follow-up met the inclusion criteria. RESULTS: Twenty-five maxillary incisors of 17 children were evaluated. The children's age at the time of therapy ranged from 24 to 72 months (mean 47.3). Pulp necrosis was the most common disorder (84.0%) and pre-operative periapical lesions were observed in 52.0%. Coronal discoloration was found in 48.0%. The roots were filled with ZOE paste (68.0%) or Guedes-Pinto paste (32.0%). Overall RCT success rate was 68.0%. The absence of pre-operative periapical lesions (p = 0.02) and pathological root resorption (p = 0.02) presented positive association with therapy success. Success was not associated to filling paste (p = 0.49), filling extent (p = 0.44), of discoloration (p = 0.39) nor the patients' age (p = 0.59). CONCLUSIONS: RCT was considered successful in 68.0% of the cases at the 24 month follow-up. Failure of RCT in traumatized primary incisors was associated with pre-operatory periapical lesions and pathological root resorption. The filling paste, the filling extent and the patient's age were unrelated with therapy success.

Incomplete caries removal in deep lesions: a 10-year prospective study.

PURPOSE: To follow-up teeth with deep caries lesions submitted to incomplete caries removal over a 10-year period. METHODS: 27 subjects (32 permanent posterior teeth) with deep caries lesions composed the sample. In this single-arm long-term prospective study, the inclusion criteria were risk of pulp exposure during caries excavation, positive response to the cold test, absence of spontaneous pain or sensitivity during percussion, and radiographic absence of a periapical lesion. Subjects were submitted to the following procedures: complete caries removal from the surrounding cavity walls, incomplete caries removal from the pulpal wall, capping with a calcium hydroxide cement, and sealing with a modified zinc oxide-eugenol cement. After 6-7 months, the temporary sealing was removed for methodological purposes (no further excavation was performed), and teeth were capped with a calcium hydroxide cement and filled with resin composite. Clinical and radiographic assessments were conducted after 6-7 months, 1.5, 3, 5 and 10 years. Success was defined as clinical and radiographic signs and symptoms of pulp sensitivity while failure was defined as endodontic treatment need. RESULTS: Over 10 years, one tooth was excluded from the sample (pulp exposure during treatment), five were lost to recall, 10 had therapy failure (five fractures and four necroses leading to endodontic treatment need, and one extraction) and 16 had therapy success (pulp sensitivity). Overall survival rates were 97%, 90%, 82% and 63% at 1.5-, 3-, 5- and 10-year follow-ups, respectively. Teeth with two or more restored surfaces failed significantly more than teeth with one restored surface (P= 0.01).

Ectopic eruption of permanent incisors after predecessor pulpectomy: five cases.

Pulpectomy in primary teeth is a common technique that preserves teeth in the oral environment and maintains or recovers periapical tissues to a healthy condition. This article describes the ectopic eruption of permanent incisors whose primary predecessors underwent pulpectomy using ZOE filler paste. In a group of 135 teeth that received pulpectomy therapy due to caries, 10 primary maxillary incisors had overretention and were followed for at least 3.5 years (mean time of 4.2 years), both clinically and radiographically, until the permanent teeth erupted. The proposed treatment included extraction of the overretained primary incisors based on permanent successor eruption chronology and contralateral eruption. Seven permanent teeth erupted ectopically. Autocorrection of the permanent tooth positions was observed in five cases. It can be concluded that periodic clinical and radiographic assessments are essential to verify radicular and filling paste resorptions and to avoid overretention and any subsequent malocclusion.

ZOE paste pulpectomies outcome in primary teeth: a systematic review.

OBJECTIVE: To perform a systematic review in which the clinical research question for primary teeth with irreversible pulpal pathosis was "how pulpectomies with zinc oxide eugenol (ZOE) paste performed compared to other materials in their clinical and radiographic outcomes after twelve months or more follow-up period. STUDY DESIGN: A literature survey of the electronic database (1950-2010) used the Medical Subject Headings and free text terms. Forty three references were retrieved and inclusion criteria were applied; 15 articles remained for full-text evaluation. From these, two were selected for data extraction regarding quality characteristics and results. RESULTS: Selected studies showed moderate or high risk of bias. The overall success of pulpectomy was 80.0% (Calcicur), 60.0% (Sealapex) and varied from 85.0% to 100.0% (ZOE) and 89.0% to 100.0% (Vitapex). Solely Calcicur presented success rate significantly lower when compared to ZOE and Vitapex. These pastes lead to overfilled canals and particles of extruded ZOE were still evident even after the evaluation period. Resorption of Vitapex, Calcicur and Sealapex within the root canal was also reported. CONCLUSIONS: In primary teeth with irreversible pulpal changes ZOE pulpectomies yielded similar outcome than Vitapex and Sealapex, although there was no agreement with regard to filling materials' resorption.

Eighteen-month clinical and radiographic evaluation of two root canal-filling materials in primary teeth with pulp necrosis secondary to trauma.

AIM: This study compared clinically and radiographically the use of zinc oxide and eugenol cement (ZOE) and a commercial calcium hydroxide and polyethylene glycol-based paste (Calen(®) ) thickened with zinc oxide as root canal-filling materials for primary teeth with pulp necrosis secondary to trauma within 18months of follow up. MATERIAL AND METHODS: Eligible patients of both genders aged 2years and 6months to 5years and 10months who had been referred for dental treatment at a pediatric dental trauma service and presented at least one anterior primary tooth (central and/or lateral incisor) with pulp necrosis secondary to traumatic injury were selected. Twenty-six children (n=31 teeth) with mean age of 3.4years met the inclusion criteria and were enrolled after parental written consent. The root canals were instrumented and filled with either ZOE (group I; n=15 teeth) or Calen(®) paste [composition: 2.5g calcium hydroxide, 0.5g zinc oxide, 0.05g colophony, and 1.75ml polyethylene glycol 400 (vehicle)] thickened with zinc oxide (Calen(®) /ZO; group II; n=16 teeth). ZO was added to the Calen(®) paste for slowing paste resorption, which should ideally occur simultaneously with the physiologic resorption of primary tooth roots. Clinical success after 18months of follow up was considered as absence of pain, tooth mobility or fistula, and radiographic success as the partial or total remission of apical periodontitis, absence of pathological root resorption or presence of new bone formation. RESULTS: Eighteen months after treatment, the teeth obturated with ZOE and Calen(®) /ZO presented statistically similar (Fisher's exact test; P >0.05) success rates of 93.3% and 87.5%, respectively. CONCLUSION: Our results showed the clinical and radiographic outcomes for Calen(®) /ZO to be equal to those for ZOE after 18months, suggesting that both materials can be indicated for obturating primary teeth with pulp necrosis after trauma.

Comparison of GPX with or without solvent and hand files in removing filling materials from root canals--an ex vivo study.

OBJECTIVE: The aim of this study was to compare GPX instruments and hand files for gutta-percha removal. STUDY DESIGN: Fifty maxillary central incisors with a single straight canal were instrumented and filled. The teeth were divided into 5 groups of 10 specimens each, according to the gutta-percha removal techniques: group 1: GPX (21-mm-long teeth); group 2: GPX and xylol as solvent (21-mm-long teeth); group 3: GPX (25-mm-long teeth); group 4: GPX and xylol as solvent (25-mm-long teeth); and group 5: hand files and xylol as solvent. The amount of time for gutta-percha removal and the number of fractured instruments were evaluated. Radiographs were taken, and the teeth were grooved longitudinally and split. The area of residual debris was measured using Sigma Scan software. RESULTS: The time for filling material removal was significantly shorter when GPX was used (P < .05). Overall, hand files and solvent produced fewer remnants of filling materials (P < .05). In the GPX 25 mm-long teeth group, the filling material was not removed in the apical third. CONCLUSIONS: Under the experimental conditions, the GPX instruments proved to be faster than hand instruments in removing root filling materials; however, hand instruments left a smaller amount of residual filling materials on the canal walls. The GPX instruments did not pull the gutta-percha beyond its tip.

Histopathological evaluation of root canal filling materials for primary teeth.

This study aimed to assess the response of apical and periapical tissues of dogs' teeth after root canal filling with different materials. Forty roots from dogs' premolars were prepared biomechanically and assigned to 4 groups filled with: Group I: commercial calcium hydroxide and polyethylene glycol-based paste (Calen) thickened with zinc oxide; Group II: paste composed of iodoform, Rifocort and camphorated paramonochlorophenol; Group III: zinc oxide-eugenol cement; Group IV: sterile saline. After 30 days, the samples were subjected to histological processing. The histopathological findings revealed that in Groups I and IV the apical and periapical regions exhibited normal appearance, with large number of fibers and cells and no resorption of mineralized tissues. In Group II, mild inflammatory infiltrate and mild edema were observed, with discrete fibrogenesis and bone resorption. Group III showed altered periapical region and thickened periodontal ligament with presence of inflammatory cells and edema. It may be concluded that the Calen paste thickened with zinc oxide yielded the best tissue response, being the most indicated material for root canal filling of primary teeth with pulp vitality.

Qualitative and quantitative radiographic assessment of sealed carious dentin: a 10-year prospective study.

OBJECTIVE: The objective of this study was to assess radiographic outcomes after partial carious dentin removal performed in deep caries lesions over a 10-year period. STUDY DESIGN: Baseline image was compared to 3 follow-up radiographs (at 6-7 months, 3 years, and 10 years). Tertiary dentin deposition and lesion depth were qualitatively assessed. Radiographic density changes in the radiolucent zone (RZ) beneath the restoration were quantitatively compared to the control areas (CA) using digital subtraction radiography (Friedman repeated-measures analysis of variance). RESULTS: A total of 13 teeth were evaluated. In most cases, lesion depth remained unchanged or decreased (12/13) and tertiary dentin formation was observed (10/13) after the 10-year follow-up. Differences between RZ and CA at the 6- to 7-month and 3-year follow-up periods were similar but significantly lower than those at the 10-year assessment. CONCLUSIONS: Sealing of carious dentin arrested the caries process, promoted deposition of tertiary dentin, and induced mineral gain in the radiolucent zone.

Periapical repair in dog teeth: root canal adhesive filling by using the Resilon System.

INTRODUCTION: New filling biomaterials with better physicochemical properties would create a favorable biologic environment for the healing of periapical tissues. The aim of this study was to evaluate periapical repair after biomechanical preparation and root filling with an adhesive system compared with the gold standard material (gutta-percha+sealer) in dog teeth. METHODS: The pulp of 25 root canals was removed. The apical cementum layer was perforated, and the root canals were prepared up to size #60 K-file followed by step-back shaping with the #90 K-file and filled by the lateral condensation technique. In the experimental group (n=15), the Resilon System (Pentron Clinical Technologies, Wallingford, CT) was used. As a control material (n=10), gutta-percha cones and pulp canal sealer were used. After 60 days, the animals were killed, and 10 histologic parameters were evaluated. Differences among the groups were analyzed by using the Mann-Whitney and Fisher exact tests. RESULTS: In radiographic and histologic evaluations, most fillings were slightly short of the apex. Progressive regenerative stages were observed; however, there was a reduced prevalence of biologic foraminal closure. No significant differences were observed between the 2 biomaterials with regard to any of the parameters evaluated (P>.05). CONCLUSIONS: The Resilon System shows periapical biocompatibility equivalent to the gold standard material.