Periodontal and endodontic infectious/inflammatory profile in primary periodontal lesions with secondary endodontic involvement after a calcium hydroxide-based intracanal medication.

OBJECTIVE: The aim of the present study was to investigate the effects of a calcium hydroxide-based intracanal medication (ICM) on periodontal and endodontic infectious/inflammatory contents and on periodontal clinical parameters in teeth with primary periodontal lesion and secondary endodontic involvement. MATERIALS AND METHODS: Ten patients with abnormal pulp test results and deep probing depth derived from primary periodontal disease with secondary endodontic involvement were included. Samples were collected from root canals (RC) and periodontal pockets (PP) in order to investigate the microbiological status, levels of endotoxin (LPS), cytokines, and matrix metalloproteinases (MMP), before and after ICM. PCR was used for microbiological assessment. The kinetic-chromogenic LAL assay was used for LPS quantification. Quantikine ELISA kits were used for measurement of IL-1 α, IL-1 ß, TNF-α, PGE2, MMP-2, MMP-3, MMP-8, MMP-9, and MMP-13 levels. The statistical analyses were made using the Friedman and Wilcoxon tests (p < 0.05). T test was used to compare data on periodontal characteristics. RESULTS: ICM did not reduce the number of microorganisms in PP and RC, except for Fusobacterium nucleatum in RC. There was a significant reduction in LPS, MMPs, IL-1 ß, and TNF-α levels in PP after ICM. In RC, LPS, MMP13, PGE2, and IL-1ß levels remained unaltered (p > 0.05); however, the levels of the other MMPs and cytokines were reduced (p < 0.05). After 1 year of the root canal treatment, tooth mobility was significantly reduced (p ≤ 0.05). CONCLUSIONS: The use of a calcium hydroxide-based ICM showed positive effects for periodontal treatment prognosis, as it reduced LPS, cytokine, and MMP levels in periodontal pockets. CLINICAL SIGNIFICANCE: Patients presenting deep probing depth and undergoing periodontal treatment for at least 6 months, with no positive response to periodontal therapy, might benefit with the endodontic treatment.

Effect of different times of nonthermal argon plasma treatment on the microtensile bond strength of self-adhesive resin cement to yttria-stabilized tetragonal zirconia polycrystal ceramic.

STATEMENT OF PROBLEM: Nonthermal argon plasma may increase the surface energy of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) dental ceramics. However, studies that evaluated the effect of increased plasma treatment times on the bond strength of resin cements to Y-TZP ceramics are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the effect of different nonthermal argon plasma (NTAP) treatment times on the surface energy and bond strength of a self-adhesive resin cement to Y-TZP ceramic. MATERIAL AND METHODS: Forty-eighty Y-TZP plates were divided into 2 groups (n=24): as-sintered (AS) and airborne-particle abrasion (APA) with 50-µm Al2O3, which were subdivided into 4 groups (n=6) according to the time of NTAP treatment: 0, 20, 60, and 120 seconds. The surface energy was evaluated with a goniometer. Forty Y-TZP blocks submitted to the same surface treatments (8 groups; n=5) were cemented to composite resin blocks, using a self-adhesive resin cement. After storage in distilled water at 37°C for 24 hours, the Y-TZP-composite resin blocks were cut into beams and submitted to a microtensile bond strength (µTBS) test. Data were analyzed using 2-way ANOVA and the Tukey honestly significant differences test (α=.05). RESULTS: Treatment with NTAP increased the surface energy for AS and APA groups (P<.05). For both groups, the µTBS was as follows: 0 seconds < 20 seconds < 60 seconds = 120 seconds (P<.05). Only after 120 seconds of NTAP treatment was the µTBS of APA higher than that of AS (P<.05). CONCLUSIONS: Treatment with NTAP improved the surface energy and increased the µTBS of self-adhesive resin cement to Y-TZP ceramic, with higher times of plasma treatment resulting in higher bond strength.

Effect of previous irrigation with chlorhexidine on the push-out bond strength of a calcium silicate-based material.

This study evaluated the effect of previous irrigation with chlorhexidine (CHX) on the bond strength of a calcium silicate-based material, Biodentine, when used for furcal repair. Furcal perforations were produced in 30 extracted mandibular molars. Teeth were divided into 3 groups according to the irrigant used: distilled water (DW), CHX followed by DW (CHX), and CHX followed by ethylenediaminetetraacetic acid (EDTA) and DW (CHX/EDTA). Biodentine was used to repair the perforations. A push-out bond strength test was performed after 7 days, and data were statistically analyzed using Kruskal-Wallis and Dunn tests (P < 0.05). The CHX/EDTA group showed significantly lower values than the DW and CHX groups (P < 0.05). The failure mode of the DW group was mainly mixed, while that of the CHX group was cohesive. The CHX/EDTA group exhibited adhesive and mixed failures. Irrigation with CHX prior to furcation repair did not result in a statistically significant difference, compared to the use of DW, in the push-out bond strength of Biodentine.

Surface roughness of different composite resins subject to in-office bleaching.

This study used atomic force microscopy to evaluate the effects of an in-office dental bleaching protocol on the surface roughness of 3 resins: microfilled, microhybrid, and nanofilled. Two disks of each resin were prepared and evaluated. Twenty-four areas (5 x 5 µm) were scanned using an atomic force microscope. Then, each disk was treated with 35% hydrogen peroxide activated by a light emitting diode. After bleaching, the disks were scanned again. Data from the 24 areas before and after bleaching were evaluated qualitatively using topographical and 3-dimensional images, as well as profile lines. Quantitatively, roughness data (mean roughness and root mean square) were statistically evaluated using standard ANOVA and Student-Newman-Keuls tests (P < 0.05). The bleaching procedure increased roughness for each resin analyzed. Based on the results, it was concluded that in-office bleaching with 35% hydrogen peroxide-based gel significantly increased the surface roughness of microfilled, microhybrid, and nanofilled resins.

Impact of Calcium-Hydroxide, Sodium Ascorbate, and Sodium Thiosulphate on Bond Strength of Composite Restorations to Bleached Dentin.

This study evaluated the impact of using calcium-hydroxide or the antioxidant agents on the bond strength of adhesive restorations to bleached dentin. Forty teeth were prepared and allocated into 8 groups according to the surface treatment after bleaching (application or not of calcium hydroxide, 10% sodium ascorbate and 5% sodium thiosulphate for 10min), and the time of final restoration (immediate or after 7-days). Sodium perborate with 20% hydrogen peroxide was applied for 3 weeks using a developed artificial pulp chamber, with replacement every week. Composite resin restoration was performed and microtensile test was performed. Then, specimens were analyzed using a stereomicroscope and SEM. Data was submitted to Kruskal-Wallis and Dunn tests (p<0.05). The bond strength of non-bleached teeth was similar to the groups restored after 7 days of bleaching (p<0.05). The lowest values of bond strength were showed by groups restored immediately after bleaching (p<0.05). In all groups, there was a considerable predominance of adhesive fractures. Delaying the final restoration of teeth submitted to nonvital bleaching for 7 days permits an increase in bond strength. The immediate restoration of bleached teeth after the use of 10% sodium ascorbate or 5% sodium thiosulfate for 10 minutes showed unsatisfactory results. Clinical relevance Irrespective of the dentin protocol applied before adhesion, a satisfactory and an unsatisfactory result of bond strength values will be obtained delaying the final restoration or immediately performing the final restoration, respectively. Therefore, after nonvital tooth bleaching, clinicians should always delay the final restoration for a minimum period of 7 days.

Influence of age and experience with magnification on locating the second mesiobuccal canal in maxillary first molars: A preliminary study.

The aim was to evaluate the effectiveness of clinical methods in identifying the presence of second mesiobuccal canal in maxillary first molars. The influence of age and experience with microscopy was also assessed. Sixty six teeth were selected and the mesiobuccal canal was confirmed in all of the samples by Cone-Beam Computed Tomography. After endodontic cavity access, teeth were evaluated through direct visual; dental loupe and operating microscope. None of the methods was successful in finding the mesiobuccal canal in all samples. Professionals <40, the magnification did not influence the location. Professionals >40, the magnification significantly influenced the location. In the direct vision, professionals >40 years located fewer canals than those <40 years of age with experience. In conclusion, these preliminary findings showed that when the microscope was used, the professionals with experience, regardless of age, found a higher number of canals. The use of the microscope was significant for professionals >40 years.

Do non-clinical subjective factors influence the treatment decisionmaking of Brazilian dentists?

The literature contains little information on several non-clinical factors such as the association between graduate residency programs and the application of minimally invasive dentistry, or on dentists' clinical decision-making processes for replacing restorations for esthetic reasons. This study evaluated whether non-clinical subjective factors influence the treatment decisions made by Brazilian dentists regarding technical and esthetic matters. Dentists were invited to participate in a cross-sectional survey by answering an electronic questionnaire containing clinical cases, regarding what treatment they would select for: T1 - a molar tooth with significant crown destruction and spontaneous pain, and T2 - premolar teeth with extensive amalgam restorations and no carious lesion or associated complaint. The survey also included questions about subjective variants (sociodemographic and professional). Chi Square test and Fischer's Exact test were used toanalyzetheanswers to T1, and one-factor analysis of variance and post-hoc Tamhane were applied to T2. The significance level was set at 5% for all analyses. A total 302 professionals participated in the study. For T1, it was found that clinical decision-making was influenced by the Brazilian region of clinical practice (p=0.005). For T2, a significant association was found between increased loss of patient tooth tissues and whether the professional had completed a residency program in Operative Dentistry (p=0.035), worked in a private practice (p=0.033), or if most of his/her patients belonged to a high estimated socioeconomic level (household income above $4350) (p=0.002). In conclusion, the clinical decision-making of Brazilian dentists varies according to professional profile, mainly with relation to the replacement of restorations due to esthetic concerns.

Vários fatores não clínicos, como a associação entre programas de especialização e a aplicação da odontologia minimamente invasiva, ainda são escassos na literatura. Outro aspecto relevante é a tomada de decisão clínica do dentista quanto à substituição de restaurações em função da aparência estética. Este estudo avaliou se fatores subjetivos não clínicos influenciam na tomada de decisão clínica de dentistas brasileiros com base em questões técnicas e estéticas. Foi realizado um estudo transversal com um questionário eletrônico contendo casos clínicos que foram apresentados a uma lista de profissionais. No questionário, interrogou-se o tratamento proposto para um dente molar com destruição coronária significativa e dor espontânea (T1). Também foi questionado o tratamento proposto para dentes prémolares com extensas restaurações de amálgama e sem lesão cariosa ou queixas associadas (T2). Em seguida, foram questionadas as variantessubjetivas(sociodemográfica eprofissional). Na análise de T1, foram utilizados os testes Qui Quadrado e Exato de Fischer. Em T2, foi aplicada a análise de variância de um fator e post-hoc Tamhane. Para todas as análises, o nível de significância foi estabelecido em 5%. Um total de 302 profissionais participaram deste estudo. A tomada de decisão clínica para T1 foi influenciada pela região brasileira de prática clínica (p = 0,005). Em T2, realizar especialização em Dentística Operatória (p = 0,035), trabalhar em consultório particular (p = 0,033) e a maioria dos pacientes apresentar nível socioeconômico estimado elevado (renda familiar acima de R$10.000,00) (p = 0,002) aumentou significativamente a perda de tecidos dentários. Em conclusão, a tomada de decisão clínica dos dentistas brasileiros varia de acordo com o perfil dos profissionais, principalmente no que se refere à substituição de restaurações por questões estéticas.

Age and experience with dental operating microscope: Do these factors influence on the post space preparation and adhesion of glass fiber posts?

This study evaluated the influence of operator's age and experience with dental operating microscope (DOM) on the cleaning of post space walls and on bond strength of glass fiber posts associated with self-adhesive resin cement. Sixty bovine roots were selected. Root canal preparation was performed and roots were filled using gutta-percha/AH Plus. For post space preparation, specimens were divided into four groups (n = 15), according to operator's age and the use of DOM: (1) ≥40 years; (2) ≥40 years with magnification; (3) <40 years; (4) <40 years with magnification. Next, a high-speed bur of the post system and torque-controlled round burs were used for cleaning of post space. Five roots in each group were evaluated for the degree of cleanliness under a stereo microscope using a scoring system. In the remaining 10 specimens from each group, glass fiber posts were cemented with RelyX U200. Two slices (1 ± 0.1 mm) prepared on each root third of all specimens were evaluated by push-out analysis. The scoring system was analyzed using Kruskal-Wallis and push-out data using ANOVA. Significance level was set at 5%. No significant difference was observed in cleaning scores among groups (p > .05). There was no significant difference when comparing the groups and the root thirds (p > .05). The adhesive failure between dentin, cement, and post predominated in all groups. Operator's age and experience with DOM did not influence the cleanliness of root canal walls or the bond strength of glass fiber posts associated with self-adhesive resin cement for post space preparation. RESEARCH HIGHLIGHTS: Although magnification is considered part of Endodontics, little is known about the variables associated. Operator's age and experience with microscope on cleaning of canals and on push-out of posts with self-adhesive resin cement were evaluated.

Effects of Two In-Office Bleaching Agents with Different Compositions on the Bond Strength to Enamel.

This study evaluates the effect of two in-office bleaching agents with different compositions on the bond strength to enamel surface. Fifty bovine teeth were divided into five groups (n = 10 teeth per group), according to the bleaching agent used and the time elapsed to perform the restorative procedures: restorative procedures performed without bleaching (control group); bleaching with 35% hydrogen peroxide (HP), with restorative procedures 24 hours or 7 days after bleaching (HP/24h and HP/7d groups, respectively); and bleaching with 35% HP with calcium compost, with restorative procedures 24 hours or 7 days after bleaching (HP AutoMixx/24h and HP AutoMixx/7d groups, respectively). The specimens were stored at 37°C in artificial saliva. Restored teeth were submitted to a micro-shear bond strength test. The specimens were analyzed using a stereoscope to determine the fracture pattern, classified as adhesive, cohesive, or mixed. The results of the bond strength test were evaluated by analysis of variance, with significance set at P < .05. The groups showed similar bond strength values without significant difference among them (P > .05). There was a predominance of the adhesive-type fracture pattern in all groups. The bleaching agents with different compositions showed similar bond strength values when the restoration was performed 24 hours and 7 days after bleaching, and the results were similar to the control group.

A second attempt at pulp revascularisation on an immature traumatised anterior tooth: a case report with two-year follow-up.

This report describes the second attempt at pulp revascularisation, using an association between 2% chlorhexidine (CHX) and calcium hydroxide (CH) as intracanal dressing, in an immature traumatised anterior tooth with pulp necrosis. A 21-year-old woman complained of pain and dental crown darkening of a permanent maxillary right central incisor. Her medical records presented a history of dental trauma, and at age 15, the first attempt at revascularisation was performed, using triple antibiotic paste (TAP) as the intracanal dressing. Recent radiographs then showed a periapical lesion associated with an immature root, which demonstrated the failure of the first attempt. The second pulp revascularisation was performed, using an association between CHX and CH as intracanal medication. The case was followed up for 24 months. Observations showed evidence of root development, dentinal wall thickening and periapical healing. In this case, the association between CHX and CH showed favourable results as an intracanal medication.

Micro-computed tomographic evaluation of smear layer and accumulated hard tissue debris removal.

BACKGROUND: The isthmus and irregularities present in the root canal system are potential areas for debris accumulation areas and therefore the seach for devices and solutions to improve cleaning of these areas is of utmust importance. This study evaluated, by micro-computed tomography, the efficiency of 37% phosphoric acid solution with that of 17% EDTA in the removal of smear layer and accumulated hard tissue debris (AHTD) after canal preparation. METHODS AND MATERIALS: Twenty-six mesial roots of mandibular molars were subjected to microtomographic scanning using the SkyScan 1173 X-ray microtomograph at a resolution of 14,97 µm. The canals were prepared using Reciproc R40 instruments, 6% NaOCl and EndoVac System® to irrigation/aspiration. After instrumentation, the specimens were divided into two groups: 37% phosphoric acid solution or 17% EDTA. RESULTS: The results demonstrated that 37% phosphoric acid was significantly more effective in removing smear layer and AHTD than 17% EDTA (Mann-Whitney, P <0.05). It was shown that both 37% phosphoric acid and 17% EDTA are effective agents in the removal of smear layer and debris, but better results were obtained with the use of 37% phosphoric acid. CONCLUSION: The results suggest that this solution can be a potential alternative to remove smear layer after root canal preparation.

Corn starch films as a long-term drug delivery system for chlorhexidine gluconate.

The present study describes the development of a chlorhexidine long-term drug delivery system using starch as a biodegradable polymer base. Three batches of thermoplastic starch films, containing starch particles/nanoparticles and chlorhexidine (CHX), were manufactured by casting. Morphological characterization showed an irregular surface with particles incorporated with chlorhexidine agglomerated in a starch matrix. Nanoindentation showed that the control film (without chlorhexidine) presented a more plastic and rigid behavior in relation to the films containing CHX. CHX was partially bounded to starch and prevented starch crystallization. Starch nanoparticles formed by precipitation were observed through transmission electron microscopy. By incorporating CHX into the solution, the nanoparticles presented different morphology, suggesting absorption of the drug. In vitro drug release was observed for 21 days by UV-vis spectrophotometry and released CHX amounted up to 19 mg/100 ml. Films presented microbiological potential for inhibiting Staphylococcus aureus growth as evaluated by the disk diffusion test in agar. It has been concluded that the developed film met the main requirements for a drug delivery system and that it is possible to be produced from a simple, cheap and reproduceable process.

Evaluation of root canal morphology of maxillary premolars: a cone-beam computed tomography study.

The aim of this study was to evaluate the root canal configuration of maxillary premolars using cone-beam computed tomography (CBCT). CBCT images of 999 maxillary premolars from a database were analysed to determine the frequency of the number of roots, root canals and Vertucci's classification. The associations among these variables were evaluated by Chi-square test (P < 0.05). In the first premolars, 42.2% of single-rooted teeth had a type II configuration, whereas 98.7% of 2-rooted teeth showed type IV. In the second premolars, type I was the most prevalent (49.9%). The presence of two roots was more prevalent in first premolars, and the presence of one root was more prevalent in second premolars (P < 0.05). Male patients had a higher percentage of two roots compared with female patients (P < 0.05). Type IV and I was more prevalent in first and second premolars respectively (P < 0.05). There was a high frequency of 2-rooted and single-rooted teeth among maxillary first and second premolars respectively.

Satisfaction Survey of Patients Using the Brazilian Version of Dental Patient Feedback on Consultation Questionnaire / Pesquisa de Satisfação de Pacientes Utilizando a Versão Brasileira do Questionário Dental Patient Feedback on Consultation skills

The aim of this study was to measure the satisfaction of patients treated in a dental hospital using a validated questionnaire on patient-dentist communication and investigate factors associated with satisfaction. Patients in the dental clinic answered 2 questionnaires: Dental Patient Feedback on Consultation (DPFC) and another regarding their oral health perceptions using a visual analog scale (VAS) and sociodemographic backgrounds. The correlation between patient's satisfaction and other numerical variables was determined using Spearman's test. The KruskalWallis and Mann-Whitney tests were used to compare the patient's satisfaction scores and the categories of the independent variables (p≤0.05). The median DPFC score was 2.9. All participants were very satisfied considering the active dentist listening (Q3) and the dental treatment advices (Q16). The lowest score was observed about family habits and medical history in oral health (Q9:2.0). With respect to their oral health perceptions, the majority of the participants demonstrated satisfaction with their chewing, smile and dental aesthetics. Being younger than 40 years influenced the satisfaction with oral health satisfaction when the VAS score was analyzed. The skin colour (p=0.001 and p=0.005) and the marital status (p=0.001 and p=0.006) of the participants also demonstrated a statistically positive signiticant correlation between DPFC and VAS scores, respectively. There was a high level of patient's satisfaction with the ability of the dentist to communicate in the dental hospital analyzed. Age, color skin, and the marital status of patients interfered in the satisfaction about patient-dentist communication and their oral health perception.(AU)

O objetivo deste estudo foi mensurar a safisfação de pacientes tratados em um hospital utilizando um questionário validado baseado na comunicação dentista-paciente e investigar os fatores associados a esta satisfação. Os pacientes da clínica responderam 2 questionários: Dental Patient Feedback on Consultation (DPFC) e outro a respeito das percepções relacionadas a saúde utilizando uma Escala Visual Analógica (EVA) e dados sociodemográficos. A correlação entre a satisfação dos pacientes e outras variáveis numéricas foi determinada através do teste de Spearman. Os testes de Kruskal-Wallis e Mann-Whitney foram usados para os escores de satisfação dos pacientes e as variáveis categóricas independents (p≤0,05). O escore mediano do DPFC foi de 2,9. Todos os participantes estavam muito satisfeitos considerando a escuta ativa do dentista (Q3) e as recomendações sobre o tratamento dentário (Q16). O escore mais baixo foi relacionado aos hábitos familiares e história médica relacionada a saúde bucal (Q9:2.0). Em relação as percepções a saúde bucal, a maioria dos participantes demonstrou satisfação com a mastigação, sorrisco e estética dental. Ter menos de 40 anos influenciou a satisfação com a saúde bucal quando a escala EVA foi utilizada. A cor da pele (p=0,001 e p=0,005) e a relação conjugal (p=0,001 e p=0,006) também demonstraram uma significância estatística positiva entre o DPFC e a escala EVA, respectivamente. Foi observado um alto nível de satisfação dos pacientes em relação a habilidade de comunicação do dentista no hospital analisado. Idade, cor da pele e a relação conjugal dos pacientes interferiu na satisfação relacionada a comunicação do dentista-paciente e a percepção de saúde bucal.(AU)

Is YouTubeTM a reliable source of information regarding ultra-thin ceramic laminates?

An aesthetic smile is usually associated with healthy appearance and success in many areas of life. Currently, individuals access the internet and social media in search of health information. The aim of this study was to analyse the quality and reliability of information in videos available on the YouTubeTM platform about ultra-thin ceramic laminates. Methods: YouTubeTM was searched using the therms "dental ceramic laminates" and "dental contact lens" for videos uploaded on ultra-thin ceramic laminates. The first 100 videos in Portuguese were selected and rated for quality and reliability. The content and source of videos were also noted. The quality of the videos was determined by evaluating the presence or absence of reliable information and distributed into seven domains. To compare the distributions of quantitative variables between the classifications of source, content, and quality, the Kruskal-Wallis and Dunn's post-hoc tests were performed. Results: Seventy-two videos were included for qualitative analysis. Regarding quality rating, most videos were rated with poor quality. The reliability of the evaluated videos was low. Conclusion: YouTubeTM showed a large number of videos with many views on the topic, but it does not contribute with good quality and reliable information to the population

Effect of photodynamic therapy and non-thermal plasma on root canal filling: analysis of adhesion and sealer penetration.

OBJECTIVE: The aim of this study was to evaluate the effect of photodynamic therapy (PDT) and non-thermal plasma (NTP) on adhesion and sealer penetration in root canals. MATERIAL AND METHODS: Sixty single-rooted premolars were used. The teeth were prepared using a crown-down technique. NaOCl and EDTA were used for irrigation and smear layer removal, respectively. The root canals were divided into three groups: control, PDT, and NTP. After treatments, the roots were filled using gutta-percha and either AH Plus (AHP) or MTA Fillapex (MTAF) sealers. Samples were sectioned at 4, 8, and 12 mm from the apex (1-mm slices)and analyzed by the push-out bond strength test (adhesion) and confocal laser scanning microscopy (sealer penetration). Data were statistically evaluated using Kruskal-Wallis, Dunn's, and Spearman's tests. RESULTS: Regarding AHP, bond strength was similar in the NTP group and in the control group, but significantly lower in the PDT group. As to MTAF, both therapies showed lower values than the control group. In the confocal analysis of AHP, maximum and mean penetration, and penetrated area were statistically higher in the control group than in the PDT and NTP groups. Penetrated perimeter was similar among groups. Regarding MTAF, all parameters yielded better results in the NTP than in the control group. The PDT and control groups showed similar results except for penetrated area. CONCLUSION: PDT and plasma therapy affected the adhesion and sealer penetration of root canals filled with AH Plus and MTA Fillapex and there is no positive correlation between adhesion and sealer penetration.

Correlation between Endodontic Infection and Periodontal Disease and Their Association with Chronic Sinusitis: A Clinical-tomographic Study.

INTRODUCTION: The proximity of the roots of maxillary posterior teeth to the maxillary sinus floor can be associated with the development of chronic maxillary sinusitis (CMS). Therefore, this study evaluated the correlation between the presence of endodontic infection and periodontal disease in maxillary posterior teeth and the presence of CMS. METHODS: A total of 83 patients (159 maxillary sinuses) were selected and underwent clinical dental examination to assess tooth mobility and pulp condition. In addition, cone-beam computed tomography was performed to evaluate the presence of periapical lesion and periodontal bone loss, and measure the distance from the root apex to the cortical of the maxillary sinus. The maxillary sinuses were divided into 2 groups: CMS and no maxillary sinusitis. Data were analyzed using χ2 test and binary logistic regression analysis (P < .05). RESULTS: Periodontal disease was positively associated with CMS, leading to a 3.45-fold higher association between these disorders (P < .05). CMS was significantly more common in patients with periodontal disease or endodontic infection in close proximity with the maxillary sinus. Periodontal disease or endodontic infection that was more distant from the maxillary sinus was more common in patients with no maxillary sinusitis (P < .05). To the extent that the tooth is more distant from the maxillary sinus floor, the chance of presenting CMS is reduced up to 2.5-fold (P < .05). CONCLUSION: Periodontal disease and proximity to the maxillary sinus are more common in cases of CMS, requiring a dental assessment and cone-beam computed tomography evaluation in patients with CMS with ineffective treatment.

The use of auxiliary devices during irrigation to increase the cleaning ability of a chelating agent.

OBJECTIVES: This study investigated the cleaning ability of ultrasonically activated irrigation (UAI) and a novel activation system with reciprocating motion (EC, EasyClean, Easy Equipamentos Odontológicos) when used with a relatively new chelating agent (QMix, Dentsply). In addition, the effect of QMix solution when used for a shorter (1 minute) and a longer application time (3 minutes) was investigated. MATERIALS AND METHODS: Fifty permanent human teeth were prepared with K3 rotary system and 6% sodium hypochlorite. Samples were randomly assigned to five groups (n = 10) according to the final irrigation protocol: G1, negative control (distilled water); G2, positive control (QMix 1 minute); G3, QMix 1 minute/UAI; G4, QMix 1 minute/EC; G5, QMix 3 minutes. Subsequently the teeth were prepared and three photomicrographs were obtained in each root third of root walls, by scanning electron microscopy. Two blinded and pre-calibrated examiners evaluated the images using a four-category scoring system. Data were statistically analyzed using Kruskal-Wallis and Dunn tests (p < 0.05). RESULTS: There were differences among groups (p < 0.05). UAI showed better cleaning ability than EC (p < 0.05). There were improvements when QMix was used with auxiliary devices in comparison with conventional irrigation (p < 0.05). Conventional irrigation for 3 minutes presented significantly better results than its use for 1 minute (p < 0.05). CONCLUSIONS: QMix should be used for 1 minute when it is used with UAI, since this final irrigation protocol showed the best performance and also allowed clinical optimization of this procedure.

The effects of non-thermal plasma and conventional treatments on the bond strength of fiber posts to resin cement.

OBJECTIVES: This study compared the effect of hexamethyldisiloxane (HMDSO) and ammonia (NH3) plasmas on the bond strength of resin cement to fiber posts with conventional treatments. MATERIALS AND METHODS: Sixty-five fiber posts were divided into 5 groups: Control (no surface treatment); H2O2 (24% hydrogen peroxide for 1 min); Blasting (blasting with aluminum oxide for 30 sec); NH3 (NH3 plasma treatment for 3 min); HMDSO (HMDSO plasma treatment for 15 min). After the treatments, the Ambar adhesive (FGM Dental Products) was applied to the post surface (n = 10). The fiber post was inserted into a silicon matrix that was filled with the conventional resin cement Allcem Core (FGM). Afterwards, the post/cement specimens were cut into discs and subjected to a push-out bond strength (POBS) test. Additionally, 3 posts in each group were evaluated using scanning electron microscopy. The POBS data were analyzed by one-way analysis of variance and the Tukey's honest significant difference post hoc test (α = 0.05). RESULTS: The Blasting and NH3 groups showed the highest POBS values. The HMDSO group showed intermediate POBS values, whereas the Control and H2O2 groups showed the lowest POBS values. CONCLUSION: Blasting and NH3 plasma treatments were associated with stronger bonding of the conventional resin cement Allcem to fiber posts, in a procedure in which the Ambar adhesive was used.

Evaluation of different surface treatments on fiber post cemented with a self-adhesive system.

Surface treatment of fiber-reinforced posts can increase adhesion, especially on the post/resin cement interface. The purpose of this in vitro study was to evaluate the effect of different surface treatments on fiber post cemented with a self-adhesive system. Sixty fiberglass epoxy resin posts were cleaned, dried and divided into 6 groups (n=10): Control (no surface treatment), silane (silane coupling agent was applied homogeneously on surface), 24% hydrogen peroxide (H2O2) (immersion during 1min), blasting (blasting with aluminum oxide for 30s), NH3 plasma (plasma treatment for 3min) and HMDSO plasma (plasma treatment for 15min). After the treatments, posts were inserted into a silicon matrix that was filled with the resin cement RelyX U200. Afterwards, the post/cement specimens were cut perpendicularly to the long axis of the posts into six 1.0mm thick discs and submitted to a push-out bond strength (POBS) test. Failure pattern was classified in 5 types: type I: cohesive in post; type II: cohesive in cement; type III: cohesive post and cement; type IV: adhesive post/cement; and type V: mixed (association between cohesive and adhesive). Data were analyzed by one-way ANOVA and Tukey HSD post hoc test (α=0.05). Silane (15.94±6.5), blasting (13.13±3.6), NH3 plasma (14.44±4.0) and HMDSO plasma (13.23±5.3) showed higher POBS when compared to control (p<0.05) and similar among them. H2O2 (9.40±4.0) treatment showed POBS values statistically similar to control (9.65±3.6). Failures were predominantly cohesive post and cement, type III, in all groups. In conclusion, surface treatments influenced in the adhesion of fiberglass post with the self-adhesive cement RelyX U200. Silane, blasting with aluminum oxide and plasmas (NH3 and HMDSO) showed results superior to 24% hydrogen peroxide.