Prevalence and Characterization of External Cervical Resorption Using Cone Beam Computed Tomography.

INTRODUCTION: The aim of this study was to assess the prevalence of external cervical resorption (ECR) and characterize the cases of ECR using cone beam computed tomography (CBCT). METHODS: High-resolution CBCT scans of 6216 patients (2280 males and 3936 females), consecutively acquired during the period July 2021 to March 2022, were analyzed. Identified cases of ECR were characterized by 3 evaluators regarding lesion height, circumferential spread, portal of entry proximity to root canal, stage, location, and width. RESULTS: In a total of 38 patients and 40 teeth, ECR cases demonstrated an incidence of 0.61%. The median age of the patients was 39 years. Prevalence of ERC was 0.78% among males and 0.50% among females. The most affected teeth were the maxillary incisors and canines. The most frequent characteristics of the lesion were: extension up to the cervical third (47.5%), more than 270° circumferential spread (42.55%), probable pulpal involvement (57.5%), progressive stage (65%), supracrestal (52.1%) and mesial (34.7%) localization of >1 mm in size (52.1%) portals of entry. Cases with greater longitudinal involvement also showed greater circumferential progression (P = .008). There was no association between portal of entry location and bone crest or ECR reparative phase (P = .42). Inter-rater agreement ranged from good to very good. No association between portal of entry and ECR progression was observed. CONCLUSIONS: ECR showed low prevalence in the Brazilian population, affecting mostly anterior maxillary teeth of patients within a wide age range. CBCT allowed characterization of ECR lesions with good interobserver agreement.

Influence of calcium hydroxide intracanal medication on bond strength of two endodontic resin-based sealers assessed by micropush-out test.

AIM: To evaluate the influence of calcium hydroxide (CH) paste used as intracanal medication on the bond strength of AH Plus (AH) and Epiphany (EP) sealers to root dentin. METHODOLOGY: Sixty palatal canals were prepared in human maxillary first molars, using a rotary system. Half of the specimens received distilled water, and the other ones received intracanal medication with CH for 14 days. Thereafter, the CH was removed and both groups were further divided into two subgroups, filled with either AH or EP. The test specimens were submitted to the micropush-out test at a speed of 0.5 mm min(-1) . Results were statistically analyzed with anova and Tukey's test at a 95% confidence level. RESULTS: The use of CH had statistically significant (P < 0.05) influence on AH only, increasing its bond strength from 19.7 ± 4.5 to 23.8 ± 2.5 (mean ± SD in MPa). In both EP groups, with (1.8 ± 0.5 MPa) and without (1.5 ± 0.9 MPa) CH, the bond strength values were statistically significantly lower than in either of the AH groups (P < 0.05). CONCLUSION: Calcium hydroxide used as intracanal medication for 14 days had a positive influence on the bond strength of AH to root dentin whereas the effect on EP was insignificant. Regardless of the intracanal medication used, AH showed considerably higher bond strength values compared with EP sealer.

Influence of dentin on pH of 2% chlorhexidine gel and calcium hydroxide alone or in combination.

The aims of endodontic treatment in cases of apical periodontitis are to reduce as much as possible the number of microorganisms inside the root canal system and to inactivate toxins produced by them. Most of the times, these objectives are not achieved solely by chemomechanical preparation, and intracanal dressing may be necessary. In these cases, calcium hydroxide is used as a root canal dressing due to its well-known and recognized antimicrobial activity. Chlorhexidine has a wide spectrum of antimicrobial activity and its association with calcium hydroxide has been recommended in an attempt to amplify antimicrobial effects of calcium hydroxide. It is also known that dentin exerts a buffering effect under wide pH variations, and may be responsible for decreasing the antimicrobial activity of drugs inside the root canal. The objectives of this study were to assess the pH of 2% chlorhexidine gel and calcium hydroxide alone or in combination, as well as the influence of dentin on the pH of these compounds. Dentin powder was obtained from bovine teeth and added as 1.8% to the volume of the medications. All substances were individually stored in plastic flasks, in triplicate. A pH meter was used at five different moments to assess pH in viscous medium: immediately after preparation and after 24 h, and 7, 14, and 21 days. Results were analyzed by paired Student's t-test. Statistically significant differences were observed in the 2% chlorhexidine gel group alone or associated with calcium hydroxide and added of dentin powder (P < 0.05). Mean pH values indicated the influence of dentin powder because of a significant increase in pH. Calcium hydroxide with propylene glycol as the vehicle always showed high pH, demonstrating that this compound was not affected by the presence of dentin.

Horizontal root fractures: a case report.

This case report describes the treatment of an upper right central incisor with an intra-alveolar horizontal root fracture at the level of the middle third and an upper left central incisor with the horizontal root fracture in the cervical third. The root fractures were reduced and rigidly splinted for 4 months. The endodontic therapy was instituted in the upper left central incisor because there was no possibility of fracture repair due to the proximity of the fracture and the gingival sulcus. As soon as the diagnosis of pulp necrosis was established in the upper left lateral incisor, the endodontic treatment was performed. After 3 years and 9 months check-up appointments showed healing in the middle root third of the upper right central incisor and it responded within normal limits to pulp testing. Thus, there is no need for endodontic therapy on this tooth.

Detecção de microrganismos oportunistas em pacientes soropositivos para o HIV e portadores de infecção endodôntica primária / Detection of opportunistic microorganisms in HIV-infected subjects associated with primary endodontic infections

O presente estudo teve por objetivo detectar espécies de enterococos, leveduras e enterobactérias, em diferentes fases da terapia endodôntica, em pacientes soropositivos para o vírus da imunodeficiência humana e portadores de infecção endodôntica primária. Os valores de células T CD4+ e carga viral foram registrados. Quinze dentes humanos unirradiculares, com diagnóstico clínico correspondente à polpa mortificada em fase crônica, com câmara pulpar fechada e que apresentavam, radiograficamente, área de rarefação óssea periapical, foram microbiologicamente analisados. As amostras foram coletadas do interior dos canais radiculares com cones de papel absorventes esterilizados e imediatamente transferidos para o meio de transporte pré-reduzido (VMGA III). Cada amostra foi diluída em água peptonada e semeada em meios seletivos e não seletivos ao desenvolvimento dos microrganismos-alvo. Os diferentes tipos morfológicos, que expressaram crescimento nos meios seletivos aos oportunistas pesquisados, foram identificados baseados no perfil bioquímico apresentado pelas amostras após semeadura em testes específicos. Durante a 1ª coleta, microrganismos foram detectados em 86,7 por cento (13:15) dos canais radiculares. Em nenhum deles, leveduras, enterococos ou enterobactérias foram isoladas. Após o preparo químico-cirúrgico, a 2ª coleta detectou microrganismos em somente 1 canal radicular (1:15 - 6,7 por cento). Após 7 dias com medicação intracanal (PRP - 2,0 g paramonoclorofenol, Rinossoro© e polietilenoglicol 400 em partes iguais para 100 mL), a 3ª coleta foi realizada e 8 canais albergavam microrganismos (8:15 - 53,3 por cento). Dentre esses, em um canal foi isolado Enterococcus avium e em dois outros leveduras, sendo identificadas como Candida albicans e Candida famata