Exploring the effectiveness of doxycycline in restorative dentistry: a systematic review of in vitro studies.

This systematic review evaluated the efficacy of doxycycline in MMP inhibition, its antibacterial action, and other properties relevant to dental materials testing. The study protocol was registered at the Open Science Framework ( https://doi.org/10.17605/OSF.IO/ZVK2T ). Reporting was based on PRISMA statement. The search was carried out in the databases: PubMed, Scopus, Web of Science, Embase, Lilacs, and Google Scholar. Articles were restricted to Portuguese, English, and Spanish, with no date limit. In vitro studies were selected based on the following outcomes: DOX antibacterial and anti-metalloproteinase activity and its influence in physico-chemical properties. Two researchers independently selected the articles and collected the data. Of 1507 documents, 82 were fully evaluated and 21 were included. Different forms of doxycycline incorporation were found, both as free form and incorporated into carrier agents. The drug was tested as primers, incorporated in adhesive or glass ionomer cement. No studies were found that evaluated its incorporation in resin composite or resin cement. The results confirmed the therapeutic properties of the medication, with more significant results when incorporated in an adhesive. However, although promising, the use of this substance requires standardization in application methods and adopted concentrations, allowing for more direct comparisons between studies. Furthermore, long-term studies are interesting to conduct, ensuring biocompatibility and complete understanding of long-term effects on dental materials.

Bleaching effectiveness and cytotoxicity of new experimental formulation of niobium-based bleaching gel.

OBJECTIVES: The development of new bleaching agents with minimum concentration of hydrogen peroxide (HP), without adverse effects, and with bleaching effectiveness, has great clinical relevance. The aim of this study was to evaluate the bleaching efficacy and cytotoxicity of a new niobium-based bleaching gel, compared to already available HP-based gels. MATERIALS AND METHODS: For the bleaching efficacy analysis, 40 bovine incisors were randomly divided into 4 groups according to the established bleaching protocol: control, untreated; 35HP, 35% HP bleaching gel; 6HP, 6% HP bleaching gel; NbHP, niobium gel associated with 3% HP gel. The color variation was measured in a spectrophotometer and the values of ΔL, Δa, Δb, and ΔE obtained. For the cell viability assay by MTT, MC3T3 cells were exposed to bleaching gel extracts (1:500, 1:250, 1:125 dilutions; immediately and 24 h). Statistical tests were performed (P < 0.05). RESULTS: The color alteration for all bleaching gels was significant compared to control (P < 0.05), but the NbHP gel showed a significant ΔE than other gels, with expressive color alteration at 14 days (P < 0.05). The 35HP showed high cytotoxicity regarding control and the most groups in all periods and extracts analyzed (P < 0.05), while the NbHP showed greater cell viability than control in the immediate period, dilution of the 1:500 and superior to 6HP in the most extracts at 24 h. CONCLUSION: The new experimental niobium-based gel has bleaching efficacy similar to that of gels with a high concentration of HP, and it has high cytocompatibility. CLINICAL RELEVANCE: The use of this new generation of niobium-based whitening gel associated with a low concentration of hydrogen peroxide represents the possibility of a tooth whitening with lower dentin sensitivity.

Conservative approach to masking a darkened tooth with a direct composite resin restoration: a case report with 5-year follow-up.

The objective of this case report is to describe a direct conservative technique for restoring the esthetics and function of a severely discolored endodontically treated tooth. A 25-year-old man presented with an esthetic complaint about severe darkening of his endodontically treated maxillary left central incisor. The tooth had adequate sound tooth structure, so the placement of a conservative direct composite resin veneer was proposed. The preparation included minimal removal of tooth structure, and a photoactivating opacifier was placed to mask the darkened substrate prior to restoration with composite resin. The restorative composite resin was placed with an incremental layering technique, restoring form, function, and esthetics. A routine follow-up examination 5 years after placement of the veneer revealed that it still provided satisfactory function and esthetics despite slight incisal wear and loss of brightness. The placement of direct composite resin veneers in association with opacifying pigments is a simple, low-cost alternative for providing immediate esthetic restoration of teeth with severe color change without extensive removal of tooth structure.

Evaluation of the clinical performance of GIOMERs and comparison with other conventional restorative materials in permanent teeth: a systematic review and meta-analysis.

Aim The aim of this systematic review and meta-analysis was to analyse the clinical performance of GIOMER restorative composites and compare them with other conventional restorative materials in permanent teeth.Methods Searches in PubMed, Web of Science, Scopus, Ovid and Cochrane Library were conducted. Grey literature search was also performed. Clinical trials that evaluated the clinical performance of restorations with GIOMER restorative composites in permanent teeth compared to those using composite resin, glass ionomer cement, resin-modified glass ionomer cement (RMGIC) and other GIOMERs were included. Meta-analyses comparing GIOMER restorative composites with RMGIC at 6- and 12-month follow-ups and comparing two types of GIOMER were feasible.Results Ten studies fulfilled the inclusion criteria. In these studies, GIOMER was compared to different types of dental restoration materials. Dental restorations were evaluated by United States Public Health Service criteria in all included studies. Four studies were suitable for meta-analysis, which showed significant differences between GIOMER and RMGIC surface roughness at 6-month (odds ratio [OR] = 6.56; 95% confidence interval [CI] = 2.38-18.13) and 12-month (OR = 8.76; CI = 3.19-24.07) follow-ups. No significant differences between GIOMER restorative composites and RMGIC for marginal adaptation were found at 6- and 12-month follow-ups. When comparing two GIOMERs, significant differences were seen between Beautifil II and Beautifil Flowable Plus F00 for marginal staining (OR = 2.58; CI = 1.42-23.27; I2 = 0%) and surface roughness (OR = 4.59; CI = 1.11-18.97; I2 = 0%) at the 36-month follow-up. No significant differences between Beautifil II and Beautifil Flowable Plus F00 were seen for marginal adaptation and anatomic form at 6-, 18- and 36-month follow-ups.Conclusions GIOMER restorative composites presented similar performance concerning marginal adaptation and better surface roughness when compared to RMGIC. GIOMER Beautifil II presented similar performance to GIOMER Beautifil Flow Plus F00 concerning marginal adaptation and anatomic form and worse marginal staining and surface roughness when compared to Beautifil Flowable Plus F00.

Is dental caries associated with liver transplantation? A systematic review and meta-analysis.

OBJECTIVE: The aim of this systematic review and meta-analysis was to evaluate the experience of dental caries in individuals pre- or postliver transplant. MATERIALS AND METHODS: Searches in PubMed, Scopus, Web of Science, Ovid, and Lilacs from databases' inception date up to April 2020 were undertaken. Gray literature and manual searches were also conducted. Observational studies were eligible. The retrieved references were evaluated by two independent reviewers. Meta-analysis and risk of bias assessment using the University of Adelaide tool were conducted. The strength of the evidence was assessed with GRADE. RESULTS: The search retrieved 1990 references. Twenty-four cross-sectional studies were included. One subgroup analysis demonstrated no significant difference in the number of teeth with dental caries between pre-liver transplant and healthy individuals (mean difference = 1.65, confidence interval = -0.87 to 4.17). The prevalence of dental caries among pre-liver transplant individuals was 73.82% and in the post-transplant individuals was 72.83%. In the included studies, the main concern regarding risk of bias was the absence of control for confounding variables. The strength of the evidence was very low. CONCLUSIONS: Dental caries may be a relevant issue in pre- and postliver transplant individuals. Oral health counseling should be included in the care of pre- and/or postliver transplant individuals.

Adaptable fiberglass post after 3D guided endodontic treatment: Novel approaches in restorative dentistry.

OBJECTIVE: The rehabilitation of extensively damaged teeth with great structural loss and calcified root canals represents a challenge for dentistry. Classically, this restorative procedure of endodontically treated teeth involves intraradicular post placement. Retentive function post that can closely adapt to the root canal without the excessive wear of intraradicular dentin has a fundamental importance to ensure the longevity of the restoration. CLINICAL CONSIDERATIONS: This report presents a clinical case of 3D guided access to a severely calcified pulp canal followed by the cementation of a fiberglass post that is adaptable to the root canal and prosthetic rehabilitation with full ceramic crown. CONCLUSIONS: 3D guided access allowed conservative and safe root canal treatment. The adaptable fiberglass post meets the specific needs of the described case and has a simple technique and low cost. CLINICAL SIGNIFICANCE: Guided endodontics is a minimally invasive approach for teeth with calcified root canals. The post used in this study meets the demands of teeth endodontically treated with conservative techniques. The professional should not need to adapt the anatomy of the root canal to the anatomical reality of the post. This one adapts itself to the shape of the canal.

Dental caries and developmental defects of enamel in individuals with chronic kidney disease: Systematic review and meta-analysis.

OBJECTIVE: To evaluate studies assessing the prevalence of dental caries and developmental defects of enamel (DDE) in individuals with chronic kidney disease (CKD) in comparison with individuals without CKD. MATERIALS AND METHODS: Electronic searches were performed in PubMed, Web of Science, Scopus, Medline via Ovid, and ProQuest databases from their inception date until February 2018. Two review authors independently selected the studies, extracted data, and assessed the methodological quality. Meta-analysis was performed. RESULTS: Twenty-seven studies were included in this study. For permanent teeth, 14 studies found that individuals without CKD had higher dental caries scores than those with CKD. However, only five studies presented results with a statistically significant difference between groups. Among the studies evaluating primary teeth, five showed that individuals without CKD had higher dental caries scores than those with CKD. Five studies showed that individuals with CKD had a significantly higher prevalence of DDE than individuals without CKD. The meta-analyses showed that individuals without CKD had significantly higher scores of dental caries teeth and surfaces than individuals with CKD. For DDE, no statistical difference between groups was observed. CONCLUSIONS: Individuals with CKD present lower dental caries scores and a higher prevalence of DDE in comparison with individuals without CKD.

Longevity, effectiveness, safety, and impact on quality of life of low-concentration hydrogen peroxides in-office bleaching: a randomized clinical trial.

OBJECTIVE: The study evaluated the longevity, effectiveness, safety, and impact on the oral health-related quality of life of in-office dental bleaching using low-concentration hydrogen peroxides. MATERIALS AND METHODS: Randomized, parallel, and double-blinded clinical trial was performed with 54 participants using 6% or 15% hydrogen peroxide (HP) in-office bleaching activated via hybrid LED/laser light. Tooth color was evaluated at baseline (T1), 1 week of bleaching (T2), 2 weeks of bleaching (T3) and 1 week (T4) and 6 months (T5) after finishing the bleaching using the Classical Vita™ scale and spectrophotometer. Tooth sensitivity and gingival irritation were measured with Visual Numeric Scale and Modified Gingival Index. The impact on quality of life was evaluated using the Oral Impact on Daily Performance. The data were analyzed using the Friedman, Mann-Whitney, and McNemar tests (p < 0.05). RESULTS: The group HP15% presented significant color change (ΔE) from T1 to T4 (p = 0.002) and T1 to T5 (p < 0.001). Parameters L, a*, and b* differed significantly at T3, T4, and T5 compared T1 for both groups. At 6-month follow-up, 57.1% of HP6 and 43.7% of HP15% participants migrated from B1 to a darker color. No significant differences were observed between the groups in tooth sensitivity, gingival irritation, or impact on quality of life. CONCLUSIONS: Both agents showed bleaching effectiveness, but HP15% presented greater color stability than HP6%, at 6-month follow-up. The agents showed low levels of tooth sensitivity, gingival irritation, and did not affect the oral health-related quality of life of the participants. CLINICAL RELEVANCE: Despite the greater presence of sensitivity during treatment compared with 6% hydrogen peroxide, 15% hydrogen peroxide demonstrated better bleaching effectiveness, and greater color stability at the end of bleaching and at 6-month follow-up. The use of 15% hydrogen peroxide presents more suitable results.

Viability of Bovine Teeth as a Substrate in Bond Strength Tests: A Systematic Review and Meta-analysis.

PURPOSE: To assess whether bovine teeth can be used as viable alternatives for human teeth in tensile and shear bond strength testing. MATERIALS AND METHODS: Articles were selected from Web of Science, PubMed, Scopus, LILACS-Bireme, and BBO electronic databases using keywords obtained from Medical Subject Headings (MeSH). Of 1540 potentially eligible studies, 157 were selected for full text analysis. Five independent reviewers (Kappa = 0.89) selected the studies, abstracted information, and assessed quality based on standardized scales. After the analysis, 78 studies comparing bovine teeth to human teeth were found. Only 18 studies comparing bovine and human substrates in bond strength tests were included in the systematic review and 13 in the meta-analysis. Two authors independently selected the studies, extracted the data and assessed the risk of bias. Mean differences were obtained by comparing tensile and shear bond strengths between human and bovine teeth (permanent and deciduous) and considering enamel and dentin separately (subgroup analysis). Statistical analysis was performed using RevMan5.1, with a random-effect model, at a 5% significance level. RESULTS: No significant difference was found between human and bovine teeth in tensile tests (p = 0.41) for dentin (p = 0.86), but there was a difference for enamel (p = 0.01). Regarding shear bond strength, no significant difference was found between human and bovine teeth (p = 0.16) either for enamel (p = 0.07) or dentin (p = 0.68). Regarding shear bond strength on deciduous teeth, no significant difference was found between human and bovine substrates (p = 0.54), either for enamel (p = 0.42) or dentin (p = 0.05). Most studies were at high (low or unclear) risk of bias. CONCLUSIONS: In shear bond strength testing, bovine teeth can be a suitable alternative for permanent and deciduous human teeth, for both enamel and dentin substrates. However, they may not be suitable for enamel tensile bond strength testing. The findings are based on low quality studies (considerable heterogeneity) and should be interpreted with caution.

Intraoral Excision of a Huge Cheek Lipoma.

Lipomas are benign tumors of mature adipocytes unusual in the oral and maxillofacial region. The average size of cheek lipomas in the literature ranges from 1.5 to 2.5 cm, with the maximum size of 5 cm. Their etiology remains unclear. Lipomas present, clinically, as well circumscribed, slow growing, painless masses, usually treated by complete excision. The aim of this paper is to present a 78-year-old Caucasian male patient with a huge cheek lipoma compromising facial esthetics and treated through an intraoral excision. Postoperative period was uneventful with no signs of recurrence. Concluding, the intraoral approach is a relatively simple technique that should be taken into account when considering the surgical removal of cheek lipomas.

Biomechanical Behavior of Tooth-Implant Supported Prostheses With Different Implant Connections: A Nonlinear Finite Element Analysis.

PURPOSE: Biomechanical behavior of tooth-implant-supported prostheses (TISPs) with external and internal implants was compared. MATERIALS AND METHODS: Two 3-D models of TISP were designed by varying the implant: external (Model EH) and internal hexagons (Model IH). After loading, von Mises stresses were obtained in implants, abutments, and screws. Principal maximum (σmax) and minimum (σmin) stresses were analyzed in periodontal ligament (PL), alveolar bone, and periimplant bone. RESULTS: Model IH showed lower stress peaks in axial loading in the implant and in the screw but higher in abutment. In oblique loading, Model IH had lower stresses in the implant, but higher in the abutment and in the screw. In the σmax analysis for axial and oblique loads, stress peaks in Model IH were lower in PL, alveolar bone, and periimplant bone. In the σmin analysis for axial load, stress peaks in Model IH were lower in PL, but higher in alveolar bone and in periimplant bone. In oblique load, Model IH showed lower stress peaks in PL and alveolar bone, but higher stress peaks in periimplant bone. CONCLUSIONS: TISPs with IH implants do present lower risk of biomechanical failure.

Comparison of different criteria for periodontitis case definition in head and neck cancer individuals.

PURPOSE: Different periodontitis case definitions have been used in clinical research and epidemiology. The aim of this study was to determine more accurate criterion for the definition of mild and moderate periodontitis case to be applied to head and neck cancer individuals before radiotherapy. METHODS: The frequency of periodontitis in a sample of 84 individuals was determined according to different diagnostic criteria: (1) Lopez et al. (2002);(2) Hujoel et al. (2006); (3) Beck et al. (1990); (4) Machtei et al. (1992); (5) Tonetti and Claffey (2005); (6) and Page and Eke (2007). All diagnosis were based on the clinical parameters obtained by a single calibrated examiner (Kw = 0.71). The individuals were evaluated before radiotherapy. They received oral hygiene instructions, and the cases diagnosed with periodontitis (Page and Eke 2007) were treated. The gold standard was the definition 6, and the others were compared by means of agreement, sensitivity (SS), specificity (SP), and the area under ROC curve. The kappa test evaluated the agreement between definitions. RESULTS: The frequency of periodontitis at baseline was 53.6 % (definition 1), 81.0 % (definition 2), 40.5 % (definition 3), 26.2 % (definition 4), 13.1 % (definition 5), and 70.2 % (definition 6). The kappa test showed a moderate agreement between definitions 6 and 2 (59.0 %) and definitions 6 and 1 (56.0 %). The criterion with higher SS (0.92) and SP (0.73) was definition 1. CONCLUSION: Definition 1 was the most accurate criterion to case periodontitis definition to be applied to head and neck cancer individuals.

Effects of Screw- and Cement-Retained Implant-Supported Prostheses on Bone: A Nonlinear 3-D Finite Element Analysis.

PURPOSE: To compare the stresses and displacements on perimplant bone generated by screw- and cement-retained prostheses using the finite element method. MATERIALS AND METHODS: Two models were constructed: partial fixed implant-supported prostheses with three elements retained by screws (SFP) or cement (CFP). Vertical and oblique loads of 100 N were applied on the models. Bone was analyzed by the principal stresses σ1 and σ3. The displacement between the implant and the bone was identified by the penetration and gap. RESULTS: Results showed a similar pattern in the distribution of the principal stresses between both prostheses. Under the σ1 stresses, the SFP showed similar values in the bone compared with the CFP. The analysis of the σ3 showed stress peaks 28% higher in the SFP, considering vertical and oblique loads. Displacement analysis showed a similar pattern and similar values between the prostheses for penetration and gap under both loads. CONCLUSIONS: There were no important differences in the σ1 analysis and the displacement between the SFP and CFP. The differences in marginal bone level reported between SFP and CFP in some clinical studies may not be related to a mechanical factor.

Two-year clinical performance of dimethacrylatebased composite restorations repaired with a silorane-based composite.

PURPOSE: To investigate the clinical performance of a silorane-based composite resin used for repairing dimethacrylate- based composite restorations. MATERIALS AND METHODS: One operator repaired defective dimethacrylate-based resin restorations that were randomly assigned to one of two treatment groups: control (n=50), repaired with Adper SE Plus and Filtek P60 Posterior Restorative (3M ESPE); or test (n=50), repaired with P90 System Adhesive Self-Etch Primer and Bond and Filtek P90 Low Shrink Posterior Restorative (3M ESPE). After 1 week, restorations were finished and polished. Two calibrated examiners (weighted Kappa≥0.78) evaluated the repaired restorations, blindly and independently, at baseline, after 6 months, 1 and 2 years. The parameters examined were marginal adaptation, anatomic form, surface roughness, marginal discoloration, postoperative sensitivity, and secondary caries. The restorations were classified as Alfa, Bravo, or Charlie, according to modified US Public Health Service criteria. Variation in the levels of clinical parameters over time was evaluated by Friedman's ANOVA (α=0.05). The Mann-Whitney test assessed the differences between the materials for all clinical criteria at baseline, 6-month, 1- and 2-year recalls (α=0.05). The Wilcoxon test compared each composite resin for all clinical criteria at the same recalls (α=0.05). RESULTS: After two years, 79 repaired restorations were re-examined. No statistically significant differences were found between the materials at baseline or at the 2-year recall (p>0.05). Comparing baseline and 2-year recall, there was a statistically significant difference for marginal discoloration (p=0.029) in silorane-based composite restorations. CONCLUSION: After two years, the clinical performance of the silorane-based composite was similar to that of the dimethacrylate-based composite when used to make repairs.

Biomechanical evaluation of screw- and cement-retained implant-supported prostheses: a nonlinear finite element analysis.

STATEMENT OF PROBLEM: The mechanical stability of the prosthetic components in the implant-prosthesis complex is essential to the long-term success of the restorations. However, little is known about the differences in the biomechanical behavior of screw- and cement-retained prostheses. PURPOSE: The purpose of this study was to compare the preload maintenance, stresses, and displacements of prosthetic components of screw- and cement-retained implant-supported prostheses by using the finite element method in a nonlinear analysis. MATERIAL AND METHODS: Two 3-dimensional models were constructed: implant-supported fixed partial prostheses with 3 elements retained either by screws (SFP) or cement (CFP). After the simulation of screw tightening, the preload was calculated for both prostheses. Then vertical and oblique loads (100 N) were applied on the models. The preload was identified, the maximum von Mises equivalent stresses (SEQV) were obtained on the screws, and the displacement among the abutment, the implant, and screw was identified by observing the penetration and gap in the contact interfaces. RESULTS: Under vertical load, there was a higher decrease in the preload and in the SEQV on the screw in the SFP. Under oblique load, the SEQV was 24% higher on the screw of the SFP. In the displacement analysis under vertical load, penetration was concentrated in the threads of the screw in the SFP and between the abutment and implant in the CFP. The gap was 118% greater for the SFP and was concentrated on the abutment extension. Under oblique load, the displacement pattern was similar for both prostheses, but with values 66% higher for penetration and 96% higher for gap for the SFP. CONCLUSIONS: The SFP showed a higher biomechanical risk of failure than the CFP.

Primary Stability and Fracture Resistance of Zirconia and Titanium Implants: A Paired Comparative In Vitro Study.

PURPOSE: Compare Neodent Zi® zirconia implants' insertion torque (IT) and removal torque (RT) with Neodent Alvim® titanium. Measure the maximum torque supported by the zirconia implant until its fracture (MT) and the maximum torque sustained by the assembler of this implant (MTA) until its fracture. MATERIAL AND METHODS: In this in-vitro study twenty four implants were used. Two groups of implants with the same macrogeometry and from the same manufacturer were compared, Zirconia (n=12) and Titanium (n=12). Implant bed preparations were completed in bovine ribs following a standardized drilling protocol. Then, the insertion torque (IT), removal torque (RT), maximum torque to fracture (MT) and maximum torque to fracture of the assembler (MTA) were completed using a calibrated torque meter. Data was presented using descriptive statistics including means, standard deviations (SD), medians, and quartiles. The Shapiro-Wilk test was used to verify data normality and the Wilcoxon test was used to evaluate differences between groups. Statistical significance was established as p < 0.05. RESULTS: Zirconia implants showed: IT 89.33 ± 31.18 Ncm and RT 84.89 ± 32.92 Ncm. Titanium implants showed: IT 77.58 ± 28.96 Ncm and RT 76.75 ± 31.29 Ncm without significant differences (p>0.05). In relation to fracture under rotational force, the zirconia implants fractured at 106.17 ± 22.54 Ncm, and the implant assembly fractured at 84.00 ±13.14 Ncm. CONCLUSION: Neodent Zi® implants showed stability but lower fracture torque than Alvim® titanium. As the fracture values of the assembler were significantly lower than the fracture values of the zirconia implants, it can be stated that, as recommended by the manufacturer, they act as a safety measure during installation.

Salivary factors associated with noncarious cervical lesions: A systematic review.

OBJECTIVE: This study aimed to carry out a systematic review of observational studies searching the association between salivary factors (amount and quality of saliva) and noncarious cervical lesions (NCCL) in individuals with permanent dentition. DESIGN: Cross-sectional, case-control, and cohort studies performed in humans with permanent dentition (population) and considering noncarious cervical lesions (outcome) in association with salivary characteristics (exposure) were included. PubMed, Web of Science, Cochrane, LILACS/BBO, Scopus, Embase, IBCT, NICE, OpenGrey, and Google Scholar were searched, with no language or date restrictions. Of 6561 potentially eligible studies, 142 were selected for full-text analysis. Three reviewers independently selected the studies, performed data extraction, and quality analysis through the Newcastle-Ottawa Scale. RESULTS: Finally, ten references were included in the review, four case-control and six cross-sectional studies. Several salivary parameters were evaluated. Some parameters were considered associated with the presence of noncarious cervical lesions: salivary buffering capacity, salivary pH, citric acid, and calcium and potassium levels. The methodological quality varied across studies, with high heterogeneity among them. CONCLUSIONS: Some associations between saliva and NCCL suggesting protective factors and others risk factors were found. However, the evidence is sparse and comes from a few studies with great heterogeneity. New scientific evidence, with standardized methods, should be encouraged. Understanding salivary parameters that influence the occurrence of NCCL is important to guide dentists in relation to etiological factors that could potentially be neglected. The results may help in the development of new and early diagnostic methods and treatments for noncarious cervical lesions.

Periodontal care in patients undergoing radiotherapy for head and neck cancer.

PURPOSE: The aim of this study was to evaluate periodontal changes after periodontal treatment and control in patients with malignant tumors of the upper aerodigestive tract who were submitted to radiotherapy with or without chemotherapy. METHODS: We included all patients attending the Oncology Clinic of the Federal University of Minas Gerais, School of Dentistry. Clinical periodontal parameters obtained by a single calibrated examiner were evaluated at baseline, 10 days after radiotherapy, and 180 days after radiotherapy. Patients were grouped into healthy or periodontally diseased individuals. All patients received oral hygiene instructions, and the diseased patients received periodontal therapy at baseline. Comparisons between the groups were performed via the McNemar and Wilcoxon tests using SPSS v. 17.0. RESULTS: A total of 28 patients were examined at baseline, of which 27 were examined 10 days after radiotherapy and 25 were examined 180 days after radiotherapy. The prevalence of periodontal disease at baseline was 67.9 % and did not decrease over time (p = 1.0). There was a significant reduction in probing depth (PD), plaque index (PI), and bleeding on probing between baseline and follow-up, which was not observed in the attachment level (AL). CONCLUSIONS: Periodontal therapy was effective in reducing PI and improving periodontal status, as evidenced by the decreases in PD and the maintenance of AL.

A method for obtaining a three-dimensional geometric model of dental implants for analysis via the finite element method.

PURPOSE: The aim of the study was to present a methodology of development of a virtual 3-dimensional dental implant model for analyses via the finite element method. MATERIALS AND METHODS: A set, consisting of a dental implant and abutment, was embedded in acrylic resin for subsequent metallographic grinding and polishing. After the evidentiation of the internal geometry of the implant, the specimen was treated in a sputter for observation using scanning electron microscopy (SEM). The SEM image was transported to computer-aided design software by which all details of the implant were measured. With the measures obtained, the geometry was reproduced with 3-dimensional modeling software. Finally, the model was imported into finite element method analysis software with which it was discretized, generating a mesh. RESULTS: A model with the accurate geometry of the implant was developed. A mesh of 297,600 elements and 490,045 nodes was generated. An aleatory acceleration simulation was performed to test the mesh, and no errors were identified. CONCLUSION: The developed methodology generated a precise dental implant model, which can be applied in different finite element method simulations.

Caries experience in a sample of adolescents and young adults with cleft lip and palate in Brazil.

Objective : To compare the caries experience of adolescents and young adults with cleft lip and/or palate (CL/P) with a noncleft control group. Design : Thirty CL/P subjects and 30 controls were clinically examined to obtain the decayed, missing and filled teeth (DMFT) and the decayed, missing and filled surfaces (DMFS) indices, gingival bleeding index, plaque index, and active caries lesions. Data concerning oral hygiene, access to fluoridated water, mother's education level, and family income were also collected. Setting : Pro-Smile Center, a reference center for the treatment of facial deformities, Alfenas, Minas Gerais, Brazil. Subjects : Subjects aged 12 to 21 years with CL/P and without associated syndromes were matched to noncleft controls by sex, age, living habits, and use of orthodontic devices. Null Hypothesis Formulated Prior to Data Collection : Caries experience in CL/P adolescents and young adults is similar to that observed in noncleft controls. Statistical Analysis : Data were analyzed using SPSS 17.0 software for Windows Data Editor. The CL/P and control groups were compared using the McNemar test, paired t test and Wilcoxon test. A significance level of 5% was adopted for all tests. Results : There were no significant differences between the groups for oral hygiene and contact with fluoride. Significant differences were found in per capita income, presence of active caries, decayed surfaces, plaque index, and gingival bleeding. Conclusions : The caries experience of CL/P subjects was higher than that of the noncleft individuals.