Clinical and radiographic outcomes of a two-piece ceramic implant: one year results from a prospective clinical trial.

OBJECTIVE: To describe the clinical and radiographic performance and survival rate of a new two-piece ceramic implant system after at least 12 months of follow-up. MATERIALS AND METHODS: Sixty-five implants were placed and followed up for at least 12 months (12.3 ± 1.5), in 50 patients. The implants were installed both in fresh extraction sockets and in healed sites and received provisional restoration when the clinical insertion torque was greater than 35Ncm. The primary results describe the survival rate of these implants. Clinical performance was evaluated through the evaluation of the Pink Esthetic Score (PES) and the degree of satisfaction of the patients. Bone loss was measured through radiographic measurements of the marginal bone loss in the mesial (MBLM) and distal (MBLD) sites. RESULTS: The survival rate was 98.5%. The average MBLM was 0.24 mm (± 0.53) and the MBLD was 0.27 mm (± 0.57). A statistical difference was observed only when comparing immediate implants with delayed ones (MBLM - p = 0.046 and MBLD - p = 0.028) and when they received immediate provisionalization or not (MBLM - p = 0.009 and MBLD - p = 0.040). The PES before the intervention (T0) was 13.4 (± 0.8) and the PES at T2 (12-month follow-up) was 12.9 (± 1.5) (p = 1.14). CONCLUSION: The new two-piece ceramic implant used in the present study showed predictable and reliable results, similar to those found with titanium implants after one year of follow-up. CLINICAL RELEVANCE: These implants can be used as an alternative to titanium implants in terms of the marginal bone loss and the degree of patient satisfaction.

Development of clinical criteria for the evaluation of indirect restorations.

OBJECTIVE: To propose the development and validation of criteria for evaluating the clinical performance of indirect restorations, considering the variables related to the operator, material, and/or patient. MATERIALS AND METHODS: The experimental design of this study was divided into three stages. Stage 1: development of the new criteria items by specialists in Prosthodontics. Step 2: creation of the criteria, named UERJ criteria, with the description of the parameters that indicate the quality of the restoration, the possible associated complications, and a detailed description of each classification. As well as the development of a form of variables. Step 3: validation of the UERJ criteria. RESULTS: Cohen's Kappa statistic registered for both intra- and inter-examiner agreements a coefficient >0.91 with a p-value <0.0001. The validity of the UERJ criteria was evaluated by tests of sensitivity (0.96) and specificity (0.91) and had a satisfactory accuracy (92.7%), a positive (10.99), and negative (0.05) likelihood ratio and high values predictive variables, with positive (PPV) 0.84 (high specificity) and negative (VPN) 0.98 (high sensitivity), with a confidence interval of 95%. CONCLUSION: The UERJ criteria is a valid instrument for evaluating the clinical performance of indirect restorations. CLINICAL SIGNIFICANCE: The UERJ criteria, developed exclusively for the analysis of indirect restorations, elucidates the details necessary to identify the causes of failures and complications of these restorations.

Filling Materials Efficacy on Preventing Biofilm Formation Inside Screw Access Channels of Implant Abutments.

The choice of the material used to fill screw access channels in implant-supported prostheses depends, in most cases, on operator's preference, without considering the susceptibility of biofilm colonization. Therefore, the aim of this study was to determine and compare the total amount of biofilm formed on different materials used to fill screw access channels in implant abutments. For this propose, titanium implant analogs were attached on abutments and divided into 5 groups: positive control (no filling material); negative control (closed with resin); and filled with cotton, gutta-percha, or polytetrafluoroethylene (PTFE). The analogs with attached abutments were then immersed in a brain heart infusion medium containing Candida albicans (strain 10231 from American Type Culture Collection [ATCC]) and incubated aerobically at 37°C with gentle agitation. After 15 days, materials were removed, and total viable biofilm on each material was quantified by methyl tetrazolium reduction assay at 490 nm. All experiments were performed in triplicate. Data were processed by IBM SPSS Statistic software using 1-way analysis of variance and Bonferroni post hoc tests to analyze differences between groups, with an overall significance level of P < .001. A significant difference was observed between cotton and gutta-percha (P < .017) and between cotton and PTFE (P < .025). However, there was no statistical difference between gutta-percha and PTFE (P > .050). Thus, this in vitro experiment showed that gutta-percha and PTFE presented lower biofilm formation compared with cotton when used to fill screw access channels. These results can provide a basis for future clinical studies that can be a guide to decreasing the occurrence of gaps and bacterial growth inside the implant/abutment attachment site. In addition, controlled in vivo studies are necessary to confirm the clinical viability of findings of this study.

Peri-Implant Surgical Treatment Downregulates the Expression of sTREM-1 and MMP-8 in Patients with Peri-Implantitis: A Prospective Study.

sTREM-1 and its ligand PGLYRP1 play an essential role in the inflammatory process around teeth and implants. In this study, we aimed to evaluate the impact of peri-implant treatment on the salivary levels of the sTREM-1/PGLYRP-1/MMP-8 axis after 3 months. A total of 42 participants (with a mean age of 61 years old ± 7.3) were enrolled in this longitudinal study, 24 having peri-implant mucositis (MU) and 18 having peri-implantitis (PI). Clinical peri-implant parameters, such as probing pocket depth (PPD), % of plaque, and bleeding on probing (BOP), and the whole unstimulated saliva samples were evaluated at baseline and 3 months after treatment. The MU group received nonsurgical peri-implant treatment, while the PI group received open-flap procedures. The levels of sTREM-1, PGLYRP-1, MMP-8, and TIMP-1 were analyzed using enzyme-linked immunosorbent assays. BOP, plaque levels, and PPD significantly reduced after treatment in both groups. A significant decrease in the salivary levels of sTREM-1, MMP-8, and TIMP-1 in the PI group and PGLYRP1 and TIMP-1 in the MU group were observed. Salivary levels of sTREM-1 were significantly reduced in patients with PI but not with MU. Additionally, peri-implant treatment had a significantly higher impact on MMP-8 reduction in patients with PI than in those with MU.

Color change, tooth sensitivity, aesthetic self-perceptions and quality of life after at-home dental bleaching / Mudança de cor, sensibilidade dental, autopercepção estética e qualidade de vida após clareamento dental caseiro

Objective: The aim of this study was to determine the color change, tooth sensitivity, aesthetic self-perception and quality of life after at-home dental bleaching. Material and Methods: Dental examination was performed and the initial color of the upper right incisor was recorded using a spectrophotometer (Easyshade Compact, Vita Zahnfabrik) and CIELab parameters. Individual vinyl trays were delivered to the patients (n=37) who were instructed to use the carbamide peroxide 16% (Total Blanc Home C16%, DFL) for 2 hours daily for 2 weeks. One-week after the end of treatment, measurements were repeated to calculate color (ΔEab,ΔE00) and whiteness index (ΔWID) variations. Oral Health Impact Profile (OHIP) and Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) questionnaires were applied before and 30 days after treatment. Tooth sensitivity was by checked by visual analogue scale (VAS). Spearnan's correlation tests were used to verify the possible relation between color change parameters and sensitivity. The Wilcoxon test was applied for results obtained by OHIP and PIDAQ questionnaires. Results: Significant color change was observed after 14 days, regardless of the considered parameter. There was no significant correlation between sensitivity and color change. The dental self-confidence domain increased after bleaching (p = 0.029) and the psychological impact decreased (p = 0.001). Conclusion:At-home dental bleaching was effective on the overall whitening and the color change was not related to tooth sensitivity. The bleaching treatment had a positive impact on the quality of life, reducing psychological discomfort and improving dental self-confidence and aesthetic self-perception. (AU)

Objetivo: O objetivo deste estudo foi determinar a mudança de cor, sensibilidade dental, autopercepção estética e qualidade de vida após clareamento dental caseiro. Material e Métodos: Uma consulta inicial foi realizada e a cor inicial do incisivo superior direito foi registrada usando um espectrofotômetro (Easyshade Compact, Vita Zahnfabrik) e parâmetros CIELab. Moldeiras individuais confeccionadas em vinil foram entregues aos pacientes participantes (n = 37), que foram instruídos a usar o gel à base de peróxido de carbamida 16% (Total Blanc Home C16%, DFL) durante 2 horas diárias durante 2 semanas. Uma semana após o término do tratamento, as medidas foram repetidas para calcular a variação de cor (ΔEab, ΔE00) e o índice de brancura (ΔWID). Os questionários OHIP (Oral Health Impact Profile) e PIDAQ (Psychosocial Impact of Dental Aesthetics Questionnaire) foram aplicados antes e 30 dias após o tratamento. A sensibilidade dental foi verificada por meio da escala visual análoga (VAS). Os testes de correlação de Spearnan foram utilizados para verificar a possível relação entre os parâmetros de mudança de cor e sensibilidade. O teste Wilcoxon foi aplicado para os resultados obtidos pelos questionários OHIP e PIDAQ. Resultados: Mudança de cor significativa foi observada após 14 dias, independentemente do parâmetro considerado. Não houve correlação significativa entre a sensibilidade e a mudança de cor. O domínio da autoconfiança dental aumentou após o branqueamento (p = 0,029) e o impacto psicológico diminuiu (p = 0,001). Conclusão: O clareamento dental caseiro foi eficaz no branqueamento geral e a mudança de cor não estava relacionada à sensibilidade dental. O tratamento clareador teve um impacto positivo na qualidade de vida, reduzindo o desconforto psicológico e melhorando a autoconfiança dental e a autopercepção estética.(AU)

In vitro evaluation of physicochemical properties of soft lining resins after incorporation of chlorhexidine.

STATEMENT OF PROBLEM: Incorporating chlorhexidine into soft lining materials has been suggested to reduce biofilm development on the material surface and treat denture stomatitis. However, evaluation of the physicochemical properties of this material is necessary. PURPOSE: The purpose of this in vitro study was to evaluate the physicochemical properties of resin-based denture soft lining materials modified with chlorhexidine diacetate (CDA). MATERIAL AND METHODS: Two soft lining resins were tested, one based on polymethyl methacrylate (PMMA) and the other on polyethyl methacrylate (PEMA), into which 0.5%, 1.0%, or 2.0% of CDA was incorporated; the control group had no CDA. The specimens were stored for 2 hours, 48 hours, 7, 14, 21, and 28 days and then analyzed for polymer crystallinity, Shore A hardness, degree of monomer conversion, residual monomer leaching, and CDA release. Data were analyzed by using a 3-way ANOVA and the Tukey HSD test (α=.05). RESULTS: The polymer crystallinity of PEMA and PMMA did not change after CDA incorporation. Shore A hardness increased over time, but not for any CDA concentrations tested after 28 days (P>.05). Considering the degree of conversion, PMMA-based resin showed no statistically significant difference (P>.05). However, PEMA-based resin showed a significant decrease (P<.05), which was reflected in a significant increase in residual monomer leaching from PEMA-based resin with the incorporation of 0.5% and 1.0% CDA (P<.05), mainly in the first 48 hours. PMMA-based resin showed no change in monomer leaching (P>.05). For both resins, the CDA release kinetics were related to monomer leaching; for PEMA-based resin, the values were significantly higher in the first 48 hours (P<.05), and for PMMA-based resin, the values were more sustained up to the last day of analysis. CONCLUSIONS: The incorporation of CDA did not affect the physicochemical properties of soft resins. The properties of PMMA were better than those of PEMA.

Evaluation of the physical and antifungal effects of chlorhexidine diacetate incorporated into polymethyl methacrylate.

OBJECTIVE: This study aimed to evaluate the physical properties and antifungal activities of polymethyl methacrylate (PMMA) acrylic resins after the incorporation of chlorhexidine diacetate salt (CDA). METHODOLOGY: First, acrylic resin specimens were fabricated with Vipi Cor® and DuraLay® resins with and without the incorporation of 0.5%, 1.0% or 2.0% CDA. The residual monomer and CDA release were measured at intervals ranging from 2 hours to 28 days using ultraviolet spectrometry combined with high-performance liquid chromatography. The antifungal activity against C. albicans was evaluated with the agar diffusion method. Fourier transform infrared spectroscopy was used to analyze the degree of resin conversion. Finally, the water sorption values of the resins were also measured. RESULTS: The incorporated CDA concentration significantly changed the rate of CDA release (p<0.0001); however, the brand of the material appeared to have no significant influence on drug release. Subsequently, the inhibition zones were compared between the tested groups and within the same brand, and only the comparisons between the CDA 2% and CDA 1% groups and between the CDA 1% and CDA 0.5% groups failed to yield significant differences. Regarding the degrees of conversion, the differences were not significant and were lower only in the CDA 2% groups. Water sorption was significantly increased at the 1.0% and 2.0% concentrations. CONCLUSIONS: We concluded that the incorporation of CDA into PMMA-based resins enabled the inhibition of C. albicans growth rate, did not alter the degrees of conversion of the tested resins and did not change the release of residual monomers.

The modulation of the TREM-1/PGLYRP1/MMP-8 axis in peri-implant diseases.

OBJECTIVES: The aim of this study is to investigate the expression of sTREM-1 and its ligand PGLYRP1, as well as the expression of MMP-8 and its inhibitor TIMP-1, in peri-implant diseases. As a secondary aim, we analyzed the influence of the concomitant existence of periodontitis in the expression of these biomarkers. MATERIALS AND METHODS: This study included 77 patients (29 males and 48 females; mean age 55.0 ± 11.5), 18 having gingivitis, 16 having periodontitis, 20 having mucositis, and 23 having peri-implantitis. Patients were clinically examined, and unstimulated whole saliva was collected. sTREM-1, PGLYRP1, MMP-8, TIMP-1, and MMP-8/TIMP1 ratio were determined by ELISA. RESULTS: The periodontitis group presented higher probing depth (PD) mean, and higher clinical attachment loss, compared with the other groups. The peri-implantitis group presented higher PD mean in implants compared to the mucositis group. Patients with PD ≥ 6 mm showed significantly higher levels of PGLYRP1, MMP-8, and MMP-8/TIMP-1 ratio than patients with PD < 6 mm. When all four markers were assessed, there were no significant differences between mucositis and peri-implantitis groups. Concomitant periodontitis resulted in higher significant levels of MMP-8 in patients with peri-implant disease. CONCLUSION: We did not observe significant differences in the levels of the sTREM-1/PGLYRP1/MMP-8 axis between patients with periodontal and peri-implant diseases, suggesting that these markers are also involved in the inflammatory process around implants. Besides, the presence of periodontitis may affect the levels of MMP-8 in patients with peri-implant disease. CLINICAL RELEVANCE: The sTREM-1/PGLYRP1/MMP-8 axis could be useful as potent markers in periodontal and peri-implant diseases.

Self-cured resin modified by quaternary ammonium methacrylates and chlorhexidine: Cytotoxicity, antimicrobial, physical, and mechanical properties.

OBJECTIVE: To evaluate the addition of dimethylaminohexadecyl methacrylate (DMAHDM) and chlorhexidine diacetate on cytotoxicity, antimicrobial activity, physical, and mechanical properties of a self-cured resin. METHODS: 132 disk-shaped and 48 rectangular specimens were divided into four experimental groups as described: Control Group (CG - no addition), dCHX (1%), DMAHDM (5%), and DMAHDM+dCHX (5%+1%). The biofilm viability, flexural strength (FS - ISO 20795-1:2013), surface roughness (SR), and color stability (ΔE) were analyzed after being stored for 4 weeks in distilled water and immersed for 72h in coffee. Cytotoxicity was measured after 24h, 3, and 7 days of elution using an MTT test on L929 cells (ISO 10993-5:2009). SR and ΔE were measured by a contact profilometer and a spectrophotometer using the CIELab parameter. Data were submitted to ANOVA and Bonferroni's/Tukey's tests (p≤0.05). RESULTS: Significant antimicrobial activity against Streptococcus mutans and Candida albicans was detected in all groups when compared to the CG (p<0.05). Only the dCHX group, in 24h of elution, demonstrated no cytotoxicity effects. There was a statistical difference for FS on the tested groups (p<0.05). No differences were detected in the initial roughness' measurements among the groups (p>0.05). However, after storage and immersion in coffee, the groups containing DMAHDM presented with rougher surfaces and significantly lower color stability compared to the control (p<0.05). SIGNIFICANCE: The addition of dCHX and DMAHDM in self-cured resin presented antimicrobial properties; however, cytotoxicity, physical, and mechanical properties were compromised.

Evaluation of the physical and antifungal effects of chlorhexidine diacetate incorporated into polymethyl methacrylate

Abstract This study aimed to evaluate the physical properties and antifungal activities of polymethyl methacrylate (PMMA) acrylic resins after the incorporation of chlorhexidine diacetate salt (CDA). Methodology: First, acrylic resin specimens were fabricated with Vipi Cor® and DuraLay® resins with and without the incorporation of 0.5%, 1.0% or 2.0% CDA. The residual monomer and CDA release were measured at intervals ranging from 2 hours to 28 days using ultraviolet spectrometry combined with high-performance liquid chromatography. The antifungal activity against C. albicans was evaluated with the agar diffusion method. Fourier transform infrared spectroscopy was used to analyze the degree of resin conversion. Finally, the water sorption values of the resins were also measured. Results: The incorporated CDA concentration significantly changed the rate of CDA release (p<0.0001); however, the brand of the material appeared to have no significant influence on drug release. Subsequently, the inhibition zones were compared between the tested groups and within the same brand, and only the comparisons between the CDA 2% and CDA 1% groups and between the CDA 1% and CDA 0.5% groups failed to yield significant differences. Regarding the degrees of conversion, the differences were not significant and were lower only in the CDA 2% groups. Water sorption was significantly increased at the 1.0% and 2.0% concentrations. Conclusions: We concluded that the incorporation of CDA into PMMA-based resins enabled the inhibition of C. albicans growth rate, did not alter the degrees of conversion of the tested resins and did not change the release of residual monomers.

Bacterial Profile and Radiographic Analysis Around Osseointegrated Implants With Morse Taper and External Hexagon Connections: Split-Mouth Model.

The aim of this clinical study was to evaluate bacterial colonization, marginal bone loss, and optical alveolar density in implants with Morse taper (MT) and external hexagon (EH) connections. Thirty-five implants were installed in 7 patients (mean age: 65.8 ± 6.7 years). Implants were divided into 2 groups, according to platform design: G1 - MT, installed 2mm infra-osseous and G2 - EH, positioned according to Branemark protocol. Patients were evaluated at baseline (T0), 21 days (T1), 3 months (T2), 6 months (T3), and 12 months (T4) after installations. Bone loss and alveolar density were evaluated by standardized periapical radiographs and bacterial profile with checkerboard DNA-DNA hybridization. Statistical analyses were performed using SPSS 23.0. To present the results, boxplots and a line graph of mean were used. P-values ≤ .05 were statistically significant. After 3 months, alveolar bone loss was significantly higher in the G2 (T2-T0: P = .006; T3-T0: P = .003; and T4-T0: P = .005). No significant differences between G1 and G2 groups were observed for optical alveolar density. Microbiological analysis showed similar profiles between studied groups; however, there were significantly higher counts of Tannerella forsythia (P = .048), Campylobacter showae (P = .038), and Actinomyces naeslundii (P = .027) in G1 after 12 months. Based on the results of this study, it can be concluded that there was less peri-implant bone loss in MT compared to EH connections, but microbiological profile did not seem to influence bone changes.

Risk factors for implant failure: a retrospective study in an educational institution using GEE analyses.

This study aimed to evaluate dental implant outcomes and to identify risk factors associated with implant failure over 12 years via dental records of patients attending an educational institution. Dental records of 202 patients receiving 774 dental implants from 2002 to 2014 were analyzed by adopting a more reliable statistical method to evaluate risk factors with patients as the unit [generalized estimating equation (GEE)]. Information regarding patient age at implantation, sex, use of tobacco, and history of systemic diseases was collected. Information about implant location in the arch region and implant length, diameter, and placement in a grafted area was evaluated after 2 years under load. Systemic and local risk factors for early and late implant failure were studied. A total of 18 patients experienced 25 implant failures, resulting in an overall survival rate of 96.8% (2.84% and 0.38% early and late implant failures, respectively). The patient-based survival rate was 91.8%. GEE univariate and multivariate analyses revealed that a significant risk factor for implant failure was the maxillary implant (p = 0.006 and p = 0.014, respectively). Bone grafting appeared to be a risk factor for implant failure (p = 0.054). According to GEE analyses, maxillary implants had significantly worse outcomes in this population and were considered to be a risk factor for implant failure. Our results suggested that implants placed in a bone augmentation area had a tendency to fail.

Th17-related cytokines in mucositis: is there any difference between peri-implantitis and periodontitis patients?

OBJECTIVE: This study aimed to compare Th17-related cytokines named IL-1ß, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, sCD40L and TNF-α in peri-implant fluid (PIF) from mucositis sites in patients having either peri-implantitis, periodontitis or without interproximal alveolar bone loss. MATERIAL AND METHODS: Thirty-three patients diagnosed with peri-implant mucositis were divided into three groups: individuals with peri-implant mucositis but without any signs of interproximal alveolar bone loss (group 1, n = 10), individuals with peri-implantitis (group 2, n = 14) and individuals with periodontitis (group 3, n = 9). Probing depth (PD), clinical attachment level (CAL), visible plaque index and bleeding on probing were measured. PIF was collected from mucositis sites in patients from the three groups and from peri-implantitis (group 2) and periodontitis sites (group 3). Cytokines were measured by a bead-based multiplex assay. RESULTS: Probing depth was significantly lower in group 1 when compared to both groups 2 and 3 (P < 0.001 and P = 0.01, respectively). There was no significant difference in cytokine levels in mucositis sites among the three groups. In group 2, IL-21 level was significantly higher in mucositis compared to peri-implantitis sites (P = 0.04). CONCLUSION: The expression of Th17-related cytokines in PIF from mucositis sites seems to be similar regardless the presence or not of alveolar bone loss around implants or teeth.

Risk factors for implant failure: a retrospective study in an educational institution using GEE analyses

Abstract This study aimed to evaluate dental implant outcomes and to identify risk factors associated with implant failure over 12 years via dental records of patients attending an educational institution. Dental records of 202 patients receiving 774 dental implants from 2002 to 2014 were analyzed by adopting a more reliable statistical method to evaluate risk factors with patients as the unit [generalized estimating equation (GEE)]. Information regarding patient age at implantation, sex, use of tobacco, and history of systemic diseases was collected. Information about implant location in the arch region and implant length, diameter, and placement in a grafted area was evaluated after 2 years under load. Systemic and local risk factors for early and late implant failure were studied. A total of 18 patients experienced 25 implant failures, resulting in an overall survival rate of 96.8% (2.84% and 0.38% early and late implant failures, respectively). The patient-based survival rate was 91.8%. GEE univariate and multivariate analyses revealed that a significant risk factor for implant failure was the maxillary implant (p = 0.006 and p = 0.014, respectively). Bone grafting appeared to be a risk factor for implant failure (p = 0.054). According to GEE analyses, maxillary implants had significantly worse outcomes in this population and were considered to be a risk factor for implant failure. Our results suggested that implants placed in a bone augmentation area had a tendency to fail.

Edentulism in Brazil: trends, projections and expectations until 2040.

The aim of this study was to examine the edentulism rates in Brazil and make projections for the next years. Data were collected from three national oral health surveys. The percentage of edentulous jaws was calculated. Projections were made for the years 2020, 2030 and 2040, assuming that edentulism follows a logistic function. Population projections were also performed. Annual change in proportion of edentulous jaws was -0.04% for teenagers, -0.96% for adults and 0.76% for the elderly. By 2040, edentulous jaws will be virtually zero among teenagers, 1.77% among adults and 85.96% among the elderly. Teenagers will slightly decrease in number; adults will increase and subsequently decrease; the elderly will continue to increase. In teenagers and adults, the number of edentulous jaws will decrease, being approximately 616,000 in 2040. In the elderly, it will increase alarmingly, reaching over 64 million in 2040. Edentulism is declining in Brazil among teenagers and middle-aged adults, but is still increasing and will continue to increase for the next decades among the elderly.

Edentulism in Brazil: trends, projections and expectations until 2040 / Edentulismo no Brasil: tendências, projeções e expectativas até 2040

Abstract The aim of this study was to examine the edentulism rates in Brazil and make projections for the next years. Data were collected from three national oral health surveys. The percentage of edentulous jaws was calculated. Projections were made for the years 2020, 2030 and 2040, assuming that edentulism follows a logistic function. Population projections were also performed. Annual change in proportion of edentulous jaws was -0.04% for teenagers, -0.96% for adults and 0.76% for the elderly. By 2040, edentulous jaws will be virtually zero among teenagers, 1.77% among adults and 85.96% among the elderly. Teenagers will slightly decrease in number; adults will increase and subsequently decrease; the elderly will continue to increase. In teenagers and adults, the number of edentulous jaws will decrease, being approximately 616,000 in 2040. In the elderly, it will increase alarmingly, reaching over 64 million in 2040. Edentulism is declining in Brazil among teenagers and middle-aged adults, but is still increasing and will continue to increase for the next decades among the elderly.

Resumo O objetivo deste estudo foi examinar as taxas de edentulismo no Brasil e fazer projeções para os próximos anos. Os dados foram coletados de três censos nacionais de saúde bucal. O percentual de arcadas edêntulas foi calculado. Foram feitas projeções para 2020, 2030 e 2040, assumindo que o edentulismo segue uma função logística. Também foram realizadas projeções populacionais. A variação anual da proporção de arcadas edêntulas foi de -0,04% para jovens, -0,96% para adultos e 0,76% para idosos. Até 2040, o percentual de arcadas edêntulas será virtualmente zero entre jovens, 1,77% entre adultos e 85,96% entre idosos. O número de jovens vai diminuir levemente; o de adultos vai aumentar e depois diminuir; e o de idosos vai continuar aumentando. Para jovens e adultos, o número de arcadas edêntulas vai diminuir, aproximando-se de 616.000 em 2040. Para os idosos, este número vai aumentar alarmantemente, alcançando mais de 64 milhões em 2040. O edentulismo está diminuindo no Brasil entre jovens e adultos, mas está aumentando e continuará a aumentar nas próximas décadas entre os idosos.

Osseointegrated implants placed at supracrestal level may harbour higher counts of A. gerencseriae and S. constellatus - a randomized, controlled pilot study.

PURPOSE: This study aimed at evaluating the bacterial colonization in dental implants inserted in the crestal or supracrestal position and correlated it to radiographic bone measurements. METHODS: Thirty-five implants with regular platform in nine patients (mean age 62.4±11.2 years) were inserted either at the bone crest level (control group) or at a suprecrestal level (test group). Radiographic examination was performed at baseline (implant installation) and after 6 months. Clinical and microbiological data were collected after 6 months. Digital radiography was used to assess bone remodeling (marginal bone loss and optical alveolar density). Bacterial profile was analyzed by checkerboard DNA-DNA hybridization, including a panel of 40 bacterial species. RESULTS: After 6 months, there were significantly higher counts of Actinomyces gerencseriae (p=0.009) and Streptococcus constellatus (p=0.05) in the test group. No significant differences between test and control groups were observed for marginal bone loss (p=0.725) and optical alveolar density (p=0.975). Probing depth was similar in both groups. CONCLUSION: Significantly higher counts of A. gerencseriae and S. constellatus were found in implants placed at the supracrestal level compared to the ones placed at the bone level. No relation was found between the installation level of dental implants and peri-implant bone remodeling.

Cytokines expression in saliva and peri-implant crevicular fluid of patients with peri-implant disease.

OBJECTIVE: This study aimed to measure the levels of GM-CSF, IL-1ß, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IFN-γ and TNF-α in peri-implant crevicular fluid (PICF) and saliva from patients with peri-implant disease. METHODS: Twenty two total edentulous patients were divided into two groups: Mucositis (MU) patients with bone loss around the implants until the first thread and pocket depth ≤3 mm, and Peri-implantitis (PI) patients with at least one implant with bone loss around two or more threads and pocket depth ≥4 mm. The clinical parameters evaluated were probing pocket depth, bleeding on probing, and percentage of plaque. PICF samples were collected from MU sites, and from shallow (SPI) and deep (DPI) sites in PI. Unstimulated whole and parotid duct saliva was collected from all patients. The cytokines were measured by a multiplexed immunoassay. RESULTS: PI patients had a higher percentage of plaque compared with MU (P = 0.02). MU sites had lower pocket depth compared to SPI (P = 0.001) and to DPI (P ≤ 0.001). In PICF, the levels of IL-1ß were significantly higher in SPI sites compared to MU (P = 0.03). In the saliva from parotid, IL-8 and IL-12 were significantly higher in patients with PI (P = 0.04). CONCLUSION: Elevated levels of IL-1ß in PICF seem to be a characteristic trait of patients with peri-implantitis. The parotid duct saliva showed a significant increase in expression of IL-8, which might be related to a systemic response.

Five-year follow-up of modified implant-supported overdenture in an iliac crest autograft failure: clinical report.

The treatment of extensive pathologic lesions in the jaw, most of the time, can generate rehabilitation problems to the patient. The solid ameloblastoma is a locally invasive odontogenic tumor with a high recurrence rate. Its treatment is aggressive and accomplished through resection with safety margin. The criterion standard for reconstruction is autogenous bone, but it can provide a high degree of resorption, causing inconvenience to the patient because of lack of rehabilitative option. This study aimed to describe a patient with ameloblastoma treated through resection and reconstruction with autogenous bone graft, in which, after an extensive resorption of the graft was made, a modified bar was applied to support a prosthetic implant overdenture.

Torque removal evaluation of prosthetic screws after tightening and loosening cycles: an in vitro study.

OBJECTIVES: The aim of this study was to evaluate the variation in removal torque of implant prosthetic abutment screws after successive tightening and loosening cycles, in addition to evaluating the influence of the hexagon at the abutment base on screw removal torque. MATERIAL AND METHODS: Twenty hexagonal abutments were tightened to 20 regular external hex implants with a titanium alloy screw, with an insertion torque of 32 N cm, measured with a digital torque gauge. The implant/abutment/screw assemblies were divided into two groups: (1) abutments without hexagon at the base and (2) abutments with a hexagon at the base. Each assembly received a provisional restoration and was submitted to mechanical loading cycles. After this, the screws were removed and the removal torque was measured. This sequence was repeated 10 times, then the screw was replaced by a new one, and another cycle was performed. Linear regression analysis was performed. RESULTS: Removal torque values tended to decrease as the number of insertion/removal cycles increased, for both groups. Comparisons of the slopes and the intercepts between groups showed no statistical difference. There was no significant difference between the mean values of last five cycles and the 11th cycle. Within the limitations of this in vitro study, it was concluded that (1) repeated insertion/removal cycles promoted gradual reduction in removal torque of screws, (2) replacing the screw with a new one after 10 cycles did not increase resistance to loosening, and (3) removal of the hexagon from the abutment base had no effect on the removal torque of the screws.