An evaluation of gingival phenotype and thickness as determined by indirect and direct methods.

OBJECTIVES: To evaluate gingival phenotype (GP) and thickness (GT) using visual, probing, and ultrasound (US) methods and to assess the accuracy and consistency of clinicians to visually identify GP. MATERIALS AND METHODS: The GP and GT of maxillary and mandibular anterior teeth in 29 orthodontic patients (mean age 25 ± 7.5 years) were assessed using probing and US by a single examiner. General dentist and dental specialist assessors (n = 104) were shown intraoral photographs of the patients, including six repeated images, and asked to identify the GP via a questionnaire. RESULTS: An increasing trend in GT values of thin, medium, and thick biotype probe categories was found, though this was not statistically significant (P = .188). Comparison of probing method to determinations of GT made by US yielded slight agreement (κ = 0.12). Using the visual method, assessors' identification of the second GP determination ranged from poor to moderate agreement (κ = 0.29 to κ = 0.53). CONCLUSIONS: The probe method is sufficient in differentiating between different categories of GP. However, further research is required to assess the sensitivity of the probe method in recognizing phenotypes in the most marginal of cases. Assessors using the visual method lack the ability to identify GP accurately and consistently among themselves.

Effect of craniofacial morphology on gingival parameters of mandibular incisors.

OBJECTIVES: To investigate the association between the width of keratinized gingiva (WKG), gingival phenotype (GP), and gingival thickness (GT) with craniofacial morphology in sagittal and vertical dimensions. MATERIALS AND METHODS: WKG, GP, and GT of mandibular anterior teeth in 177 preorthodontic patients (mean age 18.38 ± 5.16 years) were assessed clinically using a periodontal probe, a Colorvue Biotype Probe, and ultrasound by a single examiner. Patients were grouped into skeletal Class I, II, and III and hyperdivergent, normodivergent, and hypodivergent based on ANB and SN-MP angles. Mandibular incisor inclination (L1-NB) was also measured. Clinical and cephalometric measurements were repeated to assess inter- and intraexaminer reproducibility. RESULTS: A significant association was found between thin GP and skeletal Classes I and III for the left mandibular central incisor (MCI; P = .0183). In skeletal Class III patients, L1-NB angle demonstrated a decreasing trend as phenotype thickness decreased. A significant association was found between thin phenotype and normodivergent and hypodivergent groups for MCIs (left: P = .0009, right: P = .00253). No significant association between WKG or GT and craniofacial morphology was found. CONCLUSIONS: Thin GP is associated with skeletal Class I and III for the left MCI. Thin GP is associated with hypodivergent and normodivergent skeletal patterns for the MCIs. There was no association between WKG and GT and craniofacial morphology in both skeletal and vertical dimensions. Dental compensations that exist due to different craniofacial morphology may influence the GP.

The Effect of Osseodensification on Ridge Expansion, Intraosseous Temperature, and Primary Implant Stability: A Pilot Study on Bovine Ribs.

Osseodensification is a novel technique based on nonsubtractive drilling to preserve and condense bone during osteotomy preparation. The aim of this ex vivo study was to compare osseodensification and conventional extraction drilling technique with regard to intraosseous temperatures, expansion of alveolar ridge width, and primary implant stability using different implant geometries: tapered and straight walled. A total of 45 implant sites were prepared in bovine ribs following osseodensification and conventional protocols. Changes in intraosseous temperatures were recorded at 3 depths using thermocouples, and ridge width was measured at 2 different depths before and after osseodensification preparations. The primary implant stability was measured using peak insertion torque and the implant stability quotient (ISQ) following placement of straight and tapered implants. A significant change in temperature was recorded during site preparation for all techniques tested but not at all depths. Osseodensification recorded higher mean temperatures (42.7°C) than conventional drilling, particularly at the midroot level. Statistically significant ridge expansion was observed at both the crestal and apical levels in the osseodensification group. The ISQ values were significantly higher only for tapered implants placed in osseodensification sites when compared with conventional drilling sites; however, there was no difference in the primary stability between tapered and straight implants within the osseodensification group. Within the limitations of the present pilot study, osseodensification was found to increase the primary stability of straight-walled implants without overheating the bone and significantly expanded the ridge width. However, further investigation is required to determine the clinical significance of the bone expansion created by this new technique.

Increased Levels of C5a in Gingival Crevicular Fluid and Saliva of Patients with Periodontal Disease.

C5a is a powerful complement effector molecule that is considered to be an important proinflammatory mediator in several systemic chronic inflammatory diseases. However, its levels in periodontal diseases are yet to be assessed. We aimed to analyse the secretion of C5a in gingival crevicular fluid (GCF) and saliva of patients with periodontal disease. Twenty-eight patients diagnosed with stage 3-4 periodontitis and 16 periodontally healthy subjects participated in this study. GCF was collected from sites with the deepest probing depth of each patient, and volume was measured using a Periotron 8000®. One mL of unstimulated saliva was also collected. Samples were analysed using a commercially available ELISA kit. The data were analysed using the Mann-Whitney U test, Pearson's bivariate testing, and receiver operating characteristic curve. C5a was present in GCF from patients with periodontitis (1.06 ± 0.25 ng/mL) whilst it was undetected in controls. Saliva concentration was also significantly higher in periodontitis (1.82 ± 2.31 ng/mL) than controls (0.60 ± 0.72 ng/mL, p = 0.006). C5a levels were more pronounced in periodontitis in both oral fluids assessed by the present pilot study. These results suggest that the more pronounced levels of C5a in oral fluids from periodontitis patients indicate a potential role of this molecule in this disease pathogenesis, deserving to be better explored in subsequent studies.

Success Rates and Complications Associated with Single Immediate Implants: A Systematic Review.

This study examined the success rates of single immediate implants and their associated biological, hardware and aesthetic complications. Using a developed search strategy, randomized controlled trials (RCTs) on single-unit immediate implants with at least six human participants, a minimum follow-up time of 12 months and published between January 1999 and January 2021 were identified. Data was extracted independently using pre-designed data extraction forms. Information on success rates and associated biological, hardware and aesthetic complications were obtained and assessed. Out of 191 potentially eligible studies, 26 RCTs assessing 1270 patients with a total of 1326 single implants were included and further evaluated. In this review, success rate was reported to be 96.7-100% over a total of 9 studies. However, there was a lack of consensus on a universal success criterion between authors emphasizing the need for agreement. The average follow up was 29 months and most reported complications were aesthetic (63 cases, 4.7%), whilst there were relatively fewer biological, (20 cases, 1.5%), and hardware complications (24 cases, 1.8%). Success rate is an uncommon clinical outcome with 9 out of 26 of the selected RCTs reporting it. In these studies, single immediate implants showed a high success rate with low numbers of biological and hardware complications, and high patient satisfaction with aesthetics were reported in the short-term follow-up of one year.

Prevalence of the JP2 genotype of Aggregatibacter actinomycetemcomitans in the world population: a systematic review.

PURPOSE: To investigate the global prevalence of the JP2 genotype of Aggregatibacter actinomycetemcomitans (Aa). METHODS: A comprehensive electronic search of databases, PUBMED, MEDLINE, EMBASE, BIOSIS, and SCOPUS, was conducted up to August 2021. All published articles and studies were considered, excluding animal studies, editorials, personal opinions, letters to editor, conference abstracts, posters, and those studies without full text. The primary objective of this systematic review was to determine the presence of the JP2 genotype of Aa in the world population. RESULTS: A total of 295 articles were identified, of which 62 were preselected, and 51 were finally included in this review. Due to variable study designs and high heterogeneity, a meta-analysis was not conducted. A total of 9744 subjects were screened for the presence of the JP2 genotype of Aa worldwide, and only 621 cases were found positive. CONCLUSIONS: A relatively high presence of JP2 genotype of Aa was found in subjects from South America, North America, and Africa. There were no studies estimating the presence of the JP2 genotype of Aa in the Oceania region. The heterogeneity and quality of the included publications suggest that caution should be exercised when interpreting the data and that there remains an important need for additional evidence. CLINICAL RELEVANCE: Periodontitis is a highly prevalent inflammatory oral disorder with substantial aesthetic, functional, and psychological implications for patients. The JP2 genotype of Aa is implicated in the pathogenesis of periodontitis. To the best of our knowledge, there is a lack of systematic reviews estimating the presence of the JP2 genotype of Aa in the global population. We identified a relatively high presence of the JP2 genotype of Aa in specific geographic areas of the world, and we propose that cross-sectional and longitudinal studies are lacking in the Oceania region and need to be conducted to estimate the presence of the JP2 genotype of Aa in this region.

Human leukocyte antigen-G polymorphisms in periodontitis.

Objective: This study evaluated human leucocyte antigen-G gene polymorphisms in patients with periodontitis and healthy controls.Material and methods: The insertion/deletion polymorphism of 14 bp and a single nucleotide polymorphism (SNP) C > G on the position +3142 of the 3' untranslated region of the gene were analyzed in chronic periodontitis (n = 62), aggressive periodontitis (n = 24) patients and healthy individuals (n = 47).Results: Considering the 14 bp insertion/deletion, a significant deviation from Hardy-Weinberg expectations in the chronic periodontitis group was observed, but not in the other groups. No significant deviations were observed in patients and control groups considering the +3142 C > G SNP. A significant increased frequency of homozygotes for the 14 bp deletion allele was observed in the chronic periodontitis group as compared to controls. This group also presented a higher frequency of the deletion allele, which was marginally not significant. Concerning this polymorphism, no significant differences were observed between the aggressive periodontitis and healthy control groups. In addition, no significant differences were seen amongst patients and controls when considering the +3142 C > G frequencies.Conclusion: No differences were found amongst patients and controls when considering the +3142 C > G SNP haplotypes frequencies, but a significant increased frequency of homozygotes for the 14 bp deletion allele was observed in chronic periodontitis patients compared to healthy controls, suggesting a susceptibility role of this polymorphism in the pathogenesis of this condition.

Plasma cytokines levels in aggressive and chronic periodontitis.

OBJECTIVE: The present study evaluated the Th1/Th2 cytokine profile in plasma from healthy controls and different types of periodontitis patients. MATERIALS AND METHODS: The concentration of IL-2, IL-4, IL-5, IL-10, TNF-α and IFN-γ was determined in healthy controls (n = 18) and patients with chronic (n = 19) and aggressive periodontitis (n = 19) using a flow cytometric multiplex immunoassay. Means and standard deviations were calculated and compared using Kruskal-Wallis test. Spearman rho coefficient was used to correlate cytokines in the studied groups. RESULTS: Although there was no significant difference in the concentration of cytokines between groups, there was a tendency to lower levels of IL-5 and IL-10 in the aggressive periodontitis group. Stronger correlations were observed between IL-2/IL-4 and IL-2/IL-10 in healthy controls (0.938 and 0.669, respectively) compared with chronic (0.746 and 0.532) and aggressive periodontitis groups (0.395 and 0.266). When compared to healthy (0.812) and chronic periodontitis (0.845) groups, the correlation of IL-4/IL-5 was weaker in the aggressive group (0.459). CONCLUSION: No difference between systemic levels of Th1/Th2 was observed. In aggressive periodontitis patients, nevertheless, a trend towards low levels of Th2 cytokines could suggest a contribution to the development of such an exacerbated manifestation of this disease.

Periodontal conditions of individuals with Sjögren's syndrome.

BACKGROUND: Sjögren's syndrome (SjS) is a systemic autoimmune disease that might lead to hyposalivation and negatively affect the oral environment. The evidence with regard to the periodontal conditions in this group of subjects is still controversial. This study aimed to evaluate the periodontal clinical conditions and inflammatory markers in gingival crevicular fluid (GCF) from patients with primary Sjögren's syndrome (SjS [P]) or secondary Sjögren's syndrome (SjS [S]) compared to a control group. METHODS: Nineteen individuals with SjS (11 SjS [P] and eight SjS [S]) and 19 controls, matched for gender, age, and tobacco exposure, were selected from two private clinics and a hospital. The groups were compared for stimulated whole saliva (SWS) flow rate, plaque index (PI), gingival index (GI), probing depth (PD), bleeding on probing (BOP), clinical attachment level (CAL), and total amount of interleukin (IL)-1beta and total elastase activity in the GCF. Generalized estimating equations were used for data analysis. RESULTS: Individuals with SjS had a significantly lower SWS flow rate and higher mean PI, GI, PD, CAL, and BOP than controls. After adjustment for plaque, GI remained significantly higher in patients with SjS. Patients with SjS (S) had significantly higher mean CAL and PD than patients with SjS (P), and CAL and BOP remained significantly higher in this subgroup after adjustment. No differences were observed with regard to the GCF inflammatory markers. After adjusting for PD, subjects with SjS (P) showed lower levels of IL-1beta compared to controls. CONCLUSION: SjS seemed to negatively affect the periodontal condition because gingival inflammation was more evident in the individuals with SjS, particularly those with SjS (S).

A participação das células T Helper na periodontite crônica / T helper cells participation on chronic periodontitis?

As células T auxiliares ou helper (Th) são classificadas, baseadas no padrão de citocinas que produzem, em Th1 (IFN-γ), Th2 (IL-4, IL-10 e IL-13) e, mais recentemente, um novo grupo foi identificado, as células Th17 (IL-1β, IL-17,TNF-α). A resposta imune pode exibir uma característica Th1, que consiste principalmente de uma resposta imune celular pró-inflamatória, uma característica Th2, com aspecto antiinflamatório e de resposta imune humoral, ou ainda polarização Th17, com ação efetora da imunidade inata. Têm-se sugerido que a destruição dos tecidos na periodontite pode ser resultante de um desequilíbrio na regulação da resposta imune sob controle dos linfócitos Th. Alguns estudos encontraram uma polarização Th1, outros uma polarização Th2. Entretanto, há estudos que não mostraram polarização de resposta Th1 ou Th2. Ainda, evidências recentes têm colocado uma possível polarização de resposta Th17 nas lesões periodontais. Permanece incerto se há uma polarização de resposta T helper na periodontite crônica, sendo necessária a elaboração de mais estudos para que se obtenha respostas claras sobre esta questão.

T helper cells are classified based on the pattern of cytokine production in Th1-type (IL-2, IFN-γ) or Th2-type (IL-4, IL-10 and IL-13) and, more recently a new group has been identified, the Th17 cell type (IL-1β, IL17, TNF-α). The immuneresponse can exhibits a Th1 profile, consisting mainly in apro-inflammatory immune cellular response, a Th2-type, with anti-inflammatory and humoral immune response aspects, or still a Th17-type polarization, with innate immunity effectors action. It has been speculated that periodontal destruction on periodontitis might be the result of an imbalance in immune regulation under Th lymphocytes control. Some studies found a Th1 polarization in periodontitis lesions, others encountered a Th2 polarization. However, there are studies that have observed neither a Th1 nor a Th2 polarization. Moreover, recent evidence has speculated a possible Th17 dominance on periodontal tissues. It remains uncertain if there is any T helper polarization response on chronic periodontitis, reinforcing the need of more studies to reach a clearer answer about this issue.

Use of the limits of agreement approach in periodontology.

PURPOSE: To discuss the statistical approaches that have been traditionally used to compare measures in periodontal research, highlighting its strengths and weaknesses and, finally, to suggest the use of the limits of agreement method of Altman and Bland (1983) as an alternative method to address this question. MATERIALS AND METHODS: Using a sample dataset of clinical periodontal measures as a background, the different possible approaches for agreement assessment are discussed and statistical and clinical points are considered. Eight hundred and forty repeated measures, belonging to the training phase of a clinical study, were performed in five individuals presenting different severities of periodontal conditions. The use of correlation coefficient, comparison of means, linear regression technique, Kappa coefficient, intra-class correlation coefficient and means versus differences plot is demonstrated. RESULTS: Most of the methods are applied without the appropriate care, resulting in misleading interpretations. The information that arises from some of the methods used so far is poorly informative and adds little understanding to the operational characteristics of the raters or instruments. Some of the resulting information from the correlation coefficient and kappa coefficient may even be false or not applicable for the entire range of possible values. CONCLUSIONS: The graphical approach that plots differences against means, including the 95% limits of agreement estimated by the mean difference +/- 1.96 standard deviation of the differences is the most informative approach and its application should be considered for continuous clinical periodontal measures.

Artrite crônica e periodontite / Chronic arthritis and periodontitis

Como parecem existir similaridades entre os mecanismos patogenéticos de doenças reumatológicas, como a artrite reumatóide e a artrite idiopática juvenil com a periodontite, alguns estudos têm sido publicados com o objetivo de levantar evidências de uma possível inter-relação entre essas condições. A artrite reumatóide parece modular a resposta imune do hospedeiro, podendo aumentar a suscetibilidade à doença periodontal destrutiva em adultos. Recentemente, evidenciou-se que também pacientes com artrite idiopática juvenil possuíam maior suscetibilidade à doença periodontal destrutiva comparados a indivíduos saudáveis da mesma idade. No entanto, ainda se desconhecem os mecanismos que justificariam uma hipótese de associação entre essas condições crônicas inflamatórias. Sendo assim, o objetivo deste trabalho foi promover uma revisão da literatura sobre uma possível relação entre artrite crônica e periodontite.

As similarities between pathogenetic mechanisms concerning rheumatic diseases, such as rheumatoid arthritis and juvenile idiopathic arthritis, with periodontitis may exhist, some studies have been published with the objective of showing evidences of a possible relationship between these conditions. Rheumatoid arthritis seems to modulate the host's immune mechanisms and may increase the susceptibility of adults to destructive periodontal disease. Recently evidences showed that also patients with juvenile idiopathic arthritis had an increased susceptibility to destructive periodontal disease compared to healthy individuals of the same age. Nevertheless the mechanisms of association of these chronic inflammatory conditions remain unclear. So, this study aims to review literature concerning a possible relationship between chronic arthritis and periodontitis.

Periodontite crônica em paciente adulto jovem: relato de caso clínico / Chronic periodontitis in young adult patient: a case report

A diferenciação entre as formas de periodontite é importante, pois suas características podem determinar a abordagem em relação ao tratamento e prognóstico destas doenças, como por exemplo, a inclusão de terapia antimicrobiana na forma de coadjuvante da terapia mecânica, a determinação do tempo de avaliação da cicatrização pós-tratamento, da freqüência das consultas de manutenção e na necessidade de exame de familiares. Com este preceito, o objetivo deste estudo é apresentar o processo de diagnóstico de periodontite crônica em um paciente adulto jovem, o qual envolveu exames clínicos radiográficos e de familiares, assim como a seqüência de tratamento periodontal em duas fases: supra e subgengival. O resultado do tratamento em curto prazo (150 dias) mostra os excelentes resultados obtidos com relação aos parâmetros supra e subgengivais.

A resin-modified glass ionomer cement barrier for treating degree II furcation defects: a pilot study in dogs.

OBJECTIVE: The aim of this study was to evaluate in an animal model the healing of degree II furcation defects treated with: an experimental barrier of resin-modified glass-ionomer cement (GIC), a polylactic acid barrier (GUI), and flap surgery (CTR). MATERIAL AND METHODS: In 3 beagles, 18 class II furcation defects were surgically produced in mandibular and maxillary premolars and exposed to plaque accumulation for 21 days. Following a full flap, notches were made at the base to the bone defect. GIC barriers were prepared immediately before use from a commercial product and fit to place with the same product. The GIC barriers were removed after 30 days and the dogs euthanized after 120 days. Histologic sections were analyzed in a computer-assisted microscope. Epithelium, new cementum with inserting fibers, and connective tissue lining the root surface in-between notches were measured and medians of percentage values calculated. RESULTS: In the GIC, epithelium constituted 3.5% (median values) of the notch-to-notch root area; new cementum was 83.6% and connective tissue 12.9%. These values were 0%, 73.6%, and 26.4% for the GUI group and 35.6%, 43.2%, and 0% for the CTR group. Bone fill median values were 54.3% for GIC, 20.6% for GUI, and 24.6% for CTR. CONCLUSION: GIC and GUI prevented epithelial migration and promoted the formation of new periodontal tissues in experimentally induced class II furcation defects in dogs.

Clinical and histologic evaluation of the periodontal response to restorative procedures in the dog.

This study evaluated, in the dog, the periodontal response to resin-modified glass-ionomer cement or amalgam restorations placed in surgical windows and left for 124 days. Plaque control was performed in half of the sites. Histologic analyses showed that sites restored with amalgam were consistently more inflamed than sites restored with resin-modified glass-ionomer. Plaque control was associated with less inflammation in both cases. Some sites restored with resin-modified glass-ionomer presented bone repair and a connective tissue lining. The inflammatory response of the periodontium to resin-modified glass-ionomer restorations is less pronounced than that associated with amalgam restorations.

Condições periodontais em adolescentes com artrite idiopática juvenil / Periodontal conditions in adolescents with juvenile idiopathic arthritis

Periodontite e artrite reumatóide (AR) apresentam processos de destruição tecidual semelhantes. Estudos recentes têm demonstrado uma pior condição periodontal em adultos com AR em comparação a controles. Pouca evidência é disponível sobre as possíveis relações entre as doenças periodontais e as formas de artrite que afetam crianças e adolescentes, conhecida como artrite idiopática juvenil (AIJ). Esta tese é baseada na hipótese de que adolescentes com AIJ podem apresentar condições periodontais diferenciadas devido a mecanismos inflamatórios e destrutivos alterados em comum. Dessa forma, os objetivos foram: (1) avaliar as condições clínicas periodontais de um grupo de adolescentes com AIJ e de um grupo de controles saudáveis sistemicamente; (2) verificar a atividade neutrofílica (elastase) e os níveis de IL-1beta e IL-18; (3) avaliar a microbiota subgengival destes indivíduos...

Fluoride release from restorative materials coated with an adhesive

A retenção aos tecidos dentais, tanto de resinas fluoretadas, quanto de cimentos de iônomero de vidro modificados por resina, pode ser melhorada pela associação de um sistema adesivo, promovendo a formação de camada híbrida. Esta técnica traria vantagens desde que a presença do adesivo, sendo parte da camada híbrida, não funcionasse como uma barreira contra a passagem de íons flúor até a superfície dental próxima às restaurações. O objeitvo do presente estudo foi avaliar a liberação de flúor dos materiais restauradores Vitremer (3M) e Heliomolar (Vivadent), tendo como controle a resina composta Z100 (3M), através de uma aplicação de um adesivo (Scotch Bond Multi Purpose Plus - 3M). Dez discos de cada material foram preparados: 5 foram cobertos com adesivo, enquanto os demais não. Os discos foram imersos em frascos separados contendo saliva artificial, sendo esta trocada diariamente. As medidas de liberação de flúor foram feitas nos dias 1, 5, 10, 15, e 20 por um eletrodo combinado de flúor (9609 BN-Orion) coplado a um analisador de íons (A-720 Procyon). Testes ANOVA de uma via e SNK foram aplicados aos resultados para comparar os perfis de cada material. Os resultados mostraram que, com a metodologia empregada, o uso de um adesivo dental foi capaz de reduzir significantemente a liberação de flúor do material Vitremer e reduzir a níveis não detectßveis o flúor liberado pela resina fluoretada.

Fluoride release from restorative materials coated with an adhesive.

The retention of both fluoride resins and resin-modified glass ionomer cements to dental tissues can be improved by the association of an adhesive system which promotes the bonding between the resin component and dentin, forming a hybrid layer. The purpose of this investigation was to evaluate if the presence of the adhesive, being part of the hybrid layer composition, interfered with the fluoride released to tooth tissues. The restorative materials studied were: Vitremer (3M), Heliomolar (Vivadent) and Z100 (3M) using an adhesive application (Scotch Bond MultiPurpose Plus--3M). Ten discs of each material were prepared: 5 were covered with the adhesive and 5 were not. The discs were immersed in individual flasks containing artificial saliva which was changed daily. Fluoride release was measured at days 1, 5, 10, 15 and 20 by a fluoride combined electrode (9609 BN--Orion) coupled to an ion analyzer (SA-720 Procyon). One-way ANOVA and the Student-Newman-Keuls test were applied to compare the materials. The results showed that the use of a dental adhesive significantly decreased the fluoride release of Vitremer and reduced the fluoride release of Heliomolar to undetectable levels with the methodology used.

Fluoride release and uptake from glass ionomer cements and composite resins / Liberação e absorção de flúor de cimentos de ionômero de vidro e resinas compostas

O objetivo desta investigação foi avaliar a liberação e absorção de flúor de 4 cimentos de ionômero de vidro (CIVs)- Vitremer (VIT), Fuji II LC (FII LC), Fuji IX (FIX), Chelon Fill (CHE)- e duas resinas compostas (RCs)- Heliomolar (H) e Zeta-100 (Z-100). Foram confeccionados 8 discos (8 mm x 2 mm) de cada material e armazenados em recipientes plásticos contendo saliva artificial a 37°C. No grupo 1 (N = 3), os espécimes foram imersos em saliva artificial, a qual foi trocada diariamente durante 25 dias. No grupo 2 (N = 5), além de receber o mesmo tratamento dispensado ao grupo 1, os espécimes foram imersos, após 24 horas, em solução fluoretada (NaF a 1 por cento) durante 1 minuto previamente à troca diária de saliva artificial. A quantidade de flúor liberada nos dias 1, 2, 5, 10, 15, 20 e 25 foi acessada através de um eletrodo específico para flúor (9609 BN-Orion) conectado a um analisador de íons (SA-720 Procyon). Os dados foram analisados através de ANOVA de duas vias e do teste de Friedman. Os CIVs liberaram maior quantidade de flúor nas primeiras 24 horas. Após esse período, a quantidade média de flúor liberada decresceu. A resina composta H liberou flúor apenas durante as primeiras 24 horas, enquanto que a Z-100 não liberou flúor. Com relação ao tratamento com solução fluoretada, as RCs não absorveram flúor, ao contrário dos CIVs (VIT=FII LC=CHE>FIX)

Abertura coronária: guias de orientaçäo / Root canal access: guidelines

O presente estudo propöe-se a fornecer guias que orientem a localizaçäo dos canais a partir de dentes extraídos. Foram radiografados 10 incisivos centrais superiores, 10 molares superiores e 10 molares inferiores, e traçadas linhas nas radiografias tomando como ponto de referência a entrada do canal radicular e um ponto médio situado na incisal ou face oclusal. As linhas foram transferidas para a face vestibular dos dentes extraídos e a abertura coronária foi realizada com brocas da série 700, posicionados paralelamente à linha traçada. Verificou-se em todos os espécimes a coincidência da linha traçada com a entrada dos canais radiculares. Nos molares superiores o ângulo formado pelas duas linhas traçadas mediu em média 16,4º e nos molares inferiores 28,05º. A distância média da entrada do canal MV e parede externa mesial situou-se a 2,78 mm nos molares superiores e 2,63 mm nos molares inferiores. O comprimento da linha traçada nos molares superiores foi, em média, 8,8 mm, nos molares inferiores 9,15 mm e nos incisivos centrais 10,8 mm. Esses achados servem de guias para as etapas de penetraçäo da broca, localizaçäo dos canais e desgaste compensatório durante a abertura coronária