Abstract The aim of this study was to evaluate the quality of curved root canal preparation, torsional fatigue, and cyclic fatigue of rotary systems manufactured with different NiTi alloys. Ninety single-rooted canals with curvatures of 15° to 30o were scanned and divided into three groups according to the rotary system used: BT-Race (BTR) – 10.06, 35.00, 35.04; SequenceRotaryFile (SRF) – 15.04, 25.06, 35.04; and ProDesignLogic (PDL) – 25.01, 25.06, 35.05. Each system was used on three specimens. The teeth were prepared, scanned, and analyzed to assess increase in volume, transportation, and centering ability of the root canal. Torsional fatigue of glide path instruments (BTR 10.06, SRF 15.04 and PDL 25.01) and cyclic fatigue of the finishing instrument (BTR 35.04, SRF 35.04 and PDL 35.05) were obtained by analyzing completely new instruments (n = 10) and instruments after they had been used three times (n = 10). After the torsional and cyclic fatigue tests, the fractured surface of the new and used instruments were examined by scanning electron microscopy. Increase in volume, canal transportation, and centering ability showed no significant differences among the groups (p > 0.05). The torsional test showed that SRF 15.04 produced the highest torque values for both new and used instruments, followed by PDL 25.01 and BTR 10.06 (p < 0.05). PDL 25.01, both new and used, exhibited higher values of angular deflection followed by SRF 15.04 and BTR 10.06 (p < 0.05). As regards cyclic fatigue, use of PDL 35.05, both new and used, required a longer time and larger number of cycles than did SRF 35.04 and BTR 35.04 (p < 0.05). Clinical use affected the torsional fatigue of BTR; however, cyclic fatigue was not significantly affected (p < 0.05). All rotary systems were able to prepare the curved canals satisfactorily and were used safely on the three specimens. Relative to torsional fatigue, SRF 15.04 exhibited a higher torque, and PDL 25.01, higher angular deflection. BTR 10.06 was the most affected by clinical use. PDL 35.05 showed greater resistance to cyclic fatigue.

Resumo A resposta de defesa do hospedeiro ao desafio microbiano que emerge do sistema de canais radiculares leva à periodontite apical. Os objetivos deste estudo foram avaliar a expressão de citocinas pró e anti-inflamatórias e Óxido Nítrico (NO) por macrófagos após interação com Enterococcus faecalis no modo: planctônio e de biofilme desalojado; biofilme intacto estimulado por hidróxido de cálcio (CH), CH e clorexidina ou Pasta Tri Antibiótica (TAP). Para isto, a cultura de macrófagos originados de monócitos do sangue periférico de humanos (N=8) foi exposta aos diferentes tipos de bactéria por 24 horas. Então, a quantificação da produção de of Fator de Necrose Tumoral- alfa (TNF-α), interleucina (IL)-1β, IL-6, IL-10 e NO por macrófagos se deu por meio do Luminex xMAP e reação de Greiss, respectivamente. Além dos potenciais efeitos terapêuticos desses compostos, sua atividade antimicrobiana contra E. faecalis também foi testada através microscopia confocal. Os dados dos experimentos foram analisados através do teste de Kruskal-Wallis com Dunn`s post hoc (α < 0.05). Bactéria em modo de biofilme desalojado se mostrou mais agressivo ao sistema imune que as bactérias planctônicas e controle negativo induzindo a maior excreção de NO e TNF-α. Em relação ao biofilme intacto, a atividade antimicrobiana mais fraca ocorreu no grupo de CH. Os grupos CHX e TAP aumentaram significativamente a porcentagem de bactérias mortas na mesma extensão. Interessantemente, o biofilme por ele mesmo não induziu a liberação de citocinas pro-inflamatórias - exceto por NO - enquanto que o biofilme tratado com TAP ou pastas a base de CH aumentaram os níveis de IL-6; e TNF-α e IL-1 β respectivamente. Em contraste, os níveis da potente citocina anti-inflamatória (IL-10) foram aumentados pelo grupo TAP.

Abstract The host defense response to microbial challenge emerging from the root canal system leads to apical periodontitis. The aim of this study was to evaluate the expression of inflammatory cytokines and Nitric Oxide (NO) by macrophages after interaction with Enterococcus faecalis in the: plankton and dislodged biofilm mode; intact biofilm mode stimulated by calcium hydroxide (CH), CH and chlorhexidine (CHX) or Triple Antibiotic Paste (TAP). For this purpose, culture of macrophages from monocytes in human peripheral blood (N=8) were exposed to the different modes of bacteria for 24 hours. Subsequently, the cytokines, such as, Tumor Necrotic Factor- alfa (TNF-α), interleukin (IL)-1β, IL-6, IL-10; and NO were quantified by Luminex xMAP and Greiss reaction, respectively. In addition to the potential therapeutic effects of the intracanal medication, their antimicrobial activity against Enterococcus faecalis biofilm were also tested in vitro by confocal microscopy. The experiments` data were analyzed by the Kruskal-Wallis test with the Dunn post hoc test (α < 0.05). Bacteria in dislodged biofilm mode were shown to be more aggressive to the immune system than bacteria in plankton mode and negative control, inducing greater expression of NO and TNF-α. Relative to bacteria in intact biofilm mode, the weakest antimicrobial activity occurred in Group CH. In Groups CH/CHX and TAP the percentage of dead bacteria was significantly increased to the same extent. Interestingly, the biofilm itself did not induce the release of pro-inflammatory cytokines - except for NO - while the biofilm treated with TAP and CH based pastes enhanced the levels of IL-6 and TNF-α; and IL-1 β, respectively. In contrast, the levels of a potent anti-inflammatory (IL-10) were increased in Group TAP.

OBJECTIVES: This study aims to evaluate the self-perception of oral health according to the physical, psychosocial and pain/discomfort dimensions related to clinical conditions and orofacial pain of elderly people living in three different environments. METHODS: This was an observational, cross-sectional, quantitative study with a population-based approach and nonprobabilistic convenience sampling that included 81 elderly people: 27 resided in institutional homes for elderly individuals, 27 resided in an urban area and 27 resided in a rural area in the interior of Paraíba (PB) in northeastern Brazil. RESULTS: The Geriatric Oral Health Assessment Index (GOHAI) was used to assess self-perception of oral health, while the Questionnaire for Screening of Patients with Temporomandibular Disorders (QST/TMD) was used to assess the influences of orofacial pain and the biofilm indexes of teeth and prostheses. There was a statistically significant difference in the GOHAI scores among the places of residence, with the worst values associated with the rural area. According to the QST/TMD, the majority of individuals were affected by TMDs, with statistical differences for both sex and income. CONCLUSION: The biofilm analysis showed a higher incidence of clinical conditions in the rural population. The place of residence also influenced self-perception and the clinical oral health condition of elderly people; the rural population presented the worst results.

Abstract Objective This study aimed to evaluate the influence of the NiTi wire in Conventional NiTi (ProTaper Universal PTU) and Controlled Memory NiTi (ProTaper Gold PTG) instrument systems on the quality of root canal preparation. Material and Methods Twelve mandibular molars with separate mesial canals were scanned using a high-definition microcomputed tomography system. The PTU and PTG instruments were used to shape twelve mesial canals each. The canals were scanned after preparation with F2 and F3 instruments of the PTU and PTG systems. The analyzed parameters included the remaining dentin thickness at the apical and cervical levels, root canal volume and untouched canal walls. Data was analyzed for statistical significance by the Friedman and Dunn’s tests. For the comparison of data between groups, the Mann-Whitney test was used. Results In the pre-operative analysis, there were no statistically significant differences between the groups in terms of the area and volume of root canals (P>.05). There was also no statistically significant difference between the systems with respect to root canal volume after use of the F2 and F3 instruments. There was no statistical difference in the dentin thickness at the first apical level between, before and after instrumentation for both systems. At the 3 cervical levels, the PTG maintained centralization of the preparation on the transition between the F2 and F3 instruments, which did not occur with the PTU. Conclusion The Conventional NiTi (PTU) and Controlled Memory NiTi (PTG) instruments displayed comparable capabilities for shaping the straight mesial root canals of mandibular molars, although the PTG was better than the PTU at maintaining the centralization of the shape in the cervical portion.

Resumo O objetivo deste estudo foi avaliar a influência de diferentes protocolos de irrigação ultrassônica passiva na remoção de detritos em sulcos artificialmente criados nos terços radiculares cervical, médio e apical. Quarenta raízes de incisivos bovinos extraídos foram instrumentadas a 1 mm do ápice radicular com um instrumento R50 Reciproc e irrigadas com hipoclorito de sódio a 2,5%. As raízes foram então inseridas numa mufla e clivadas em duas hemisecções. Sulcos (3 mm de comprimento) foram feitos a 2, 7 e 12 mm do ápice radicular em uma hemisecção e preenchidos com detritos dentinários. As hemisecções foram reagrupadas na mufla e divididas em 4 grupos (n = 10) de acordo com o protocolo de irrigação final: Grupo controle: 3x20 s usando agulha de calibre #30 sem agitação da solução irrigadora; Grupo PUI-s (static passive ultrasonic irrigation): 3x20 s de irrigação ultra-sônica passiva com a ponta do inserto mantida estática no terço apical; Grupo PUI-t (Irrigação ultrassônica passiva por terço): 20 s de PUI em cada terço; Grupo PUI-d (Irrigação ultrassônica dinâmica): 3x20 s de PUI movendo dinamicamente o inserto em toda extensão do canal radicular. Em todos os grupos, foi utilizado um total de 6 mL de hipoclorito de sódio a 2,5% como irrigante. Após estes procedimentos, os sulcos foram analisadas com um estereomicroscópio e pontuações foram atribuídas quanto à remoção dos detritos. Os dados foram analisados estatisticamente (a=0.05). Os resultados mostraram uma melhor limpeza em todos os grupos onde a solução de irrigação foi agitada com dispositivo ultrassônico do que no grupo controle (p<0,05). No terço apical, o PUI-d e o PUI-s apresentaram performance semelhantes (p>0,05) e melhor limpeza do que o PUI-t (p<0,05). Os métodos dinâmico e estático de agitação da solução de irrigação proporcionaram uma limpeza mais eficaz. O PUID promoveu os sulcos mais completamente limpos sugerindo que seu uso é o mais adequado em casos de dentes com anatomia de canal complexa.

Abstract The aim of this study was to evaluate the influence of different passive ultrasonic irrigation protocols on the removal of debris in artificially created grooves in the cervical, middle and apical root thirds. Forty extracted bovine incisor roots were instrumented to 1 mm of the root apex with a R50 Reciproc instrument and irrigated with 2.5% sodium hypochlorite. The roots were then inserted in a muffle and cleaved into two hemisections. Grooves (3-mm long) were done at 2, 7 and 12 mm from the root apex in one hemisection and filled with dentinal debris. The hemisections were regrouped into the muffle and divided into 4 groups (n=10) according to the final irrigation protocol: Control group: 3x20 s using a #30 gauge needle without agitation of the irrigating solution; Group PUI-s (static passive ultrasonic irrigation): 3x20 s of passive ultrasonic irrigation with the tip of the insert maintained static on the apical third; Group PUI-t (passive ultrasonic irrigation per third): 20 s of PUI in each third; Group PUI-d (passive dynamic ultrasonic irrigation): 3x20 s of PUI dynamically moving the insert in the whole extent of the root canal. In all groups, was used a total of 6 mL of 2.5% sodium hypochlorite as irrigant. After these procedures, the grooves were analyzed with a stereomicroscope and assigned scores as regards removal of the debris. The data were analyzed statistically (a=0.05). The results showed a better cleaning in all the groups where the irrigating solution was agitated with ultrasonic device than in the control group (p<0.05). In the apical third, the PUI-d and PUI-s showed similar performance (p>0.05) and a better cleanness than PUI-t (p<0.05). The dynamic and static methods of agitation of the irrigating solution provided more effective cleaning. PUI-d provided the most completely clean grooves suggesting that its use is the most adequate in cases of teeth with complex canal anatomy.