Salivary Metabolomic Analysis Reveals Amino Acid Metabolism Shift in SARS-CoV-2 Virus Activity and Post-Infection Condition.

The SARS-CoV-2 virus primarily infects salivary glands suggesting a change in the saliva metabolite profile; this shift may be used as a monitoring instrument during SARS-CoV-2 infection. The present study aims to determine the salivary metabolomic profile of patients with and post-SARS-CoV-19 infection. Patients were without (PCR-), with SARS-CoV-2 (PCR+), or post-SARS-CoV-2 infection. Unstimulated whole saliva was collected, and the 1H spectra were acquired in a 500 MHz Bruker nuclear magnetic resonance spectrometer at 25 °C. They were subjected to multivariate analysis using principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), as well as univariate analysis through t-tests (SPSS 20.0, IL, USA), with a significance level of p < 0.05. A distinction was found when comparing PCR- subjects to those with SARS-CoV-2 infection. When comparing the three groups, the PLS-DA cross-validation presented satisfactory accuracy (ACC = 0.69, R2 = 0.39, Q2 = 0.08). Seventeen metabolites were found in different proportions among the groups. The results suggested the downregulation of major amino acid levels, such as alanine, glutamine, histidine, leucine, lysine, phenylalanine, and proline in the PCR+ group compared to the PCR- ones. In addition, acetate, valerate, and capronic acid were higher in PCR- patients than in PCR+. Sucrose and butyrate were higher in post-SARS-CoV-2 infection compared to PCR-. In general, a reduction in amino acids was observed in subjects with and post-SARS-CoV-2 disease. The salivary metabolomic strategy NMR-based was able to differentiate between non-infected individuals and those with acute and post-SARS-CoV-19 infection.

SARS-COV-2 detection in saliva and nasopharyngeal swabs using RT-PCR was similar.

The World Health Organization has declared the widespread spread of SARS-CoV-2 and its associated disease (COVID-19) a public health emergency. The standard gold test for detecting the virus is the RT-PCR, performed from nasopharyngeal swab (NPS) samples. However, this test may be uncomfortable for the patient and requires specific training and attire from the health professional responsible for collecting the sample. Therefore, the search for alternative ways to collect samples that may be used in the diagnosis of COVID-19 is relevant. This study aimed to compare the results obtained from NPS and saliva samples. NPS and saliva samples were collected from 189 symptomatic outpatients suspected of COVID-19, who came to Piquet Carneiro Polyclinic. RNA extraction was performed using the Bio-Gene DNA/RNA Viral Extraction kit (Bioclin®). Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) reactions used the Molecular SARS-CoV-2 (E / RP) kit (Bio-Manguinhos). The results indicated that 142 showed a non-detectable result (ND), while 47 showed a detectable result (D). Among the 142 "ND", 137 (94.4%) saliva samples obtained the same result, while 5 samples (3.4%) were "D". Among the 47 "D" swab samples, 35 (74.4%) showed the same result in the saliva samples. The sensitivity of the saliva test was 0.74 and the specificity was 0.97. The positive predictive value was 0.88 while the negative predictive value was 0.92. The results showed that detection of Sars-CoV-2 using saliva samples showed high sensitivity and specificity compared to nasopharyngeal swabs.

Lateral Alveolar Ridge Augmentation with Autogenous Tooth Block Graft Compared with Autogenous Bone Block Graft: a Systematic Review.

Objectives: The objective of the present systematic review was to evaluate the current knowledge of implant treatment outcome following lateral alveolar ridge augmentation with autogenous tooth block graft compared with autogenous bone block graft prior to implant placement. Material and Methods: MEDLINE (PubMed), Embase and Cochrane Library search in combination with hand-search of relevant journals was conducted including human studies published in English through December 20, 2021. Comparative and non-comparative studies assessing lateral alveolar ridge augmentation with autogenous tooth block graft were included. Quality and risk-of-bias assessment were evaluated by Cochrane risk of bias tool, Newcastle-Ottawa Scale and GRADE system. Results: One comparative study characterized by low grade and two non-comparative studies fulfilled the inclusion criteria. No significant difference in short-term implant survival, health status of the peri-implant tissue or frequency of complications between the two treatment modalities was observed. Postoperative dimensional changes of the alveolar ridge width were significant diminished with tooth block compared with bone block (P = 0.0029). Consequently, the gain in alveolar ridge width was significantly higher with tooth block, after 26 weeks (P = 0.014). However, a higher frequency of short-term peri-implant mucositis was observed with tooth block. Conclusions: Lateral alveolar ridge augmentation with tooth block seems to be a suitable alternative to bone block. However, results of the present systematic review are based on short-term studies involving small patient samples. Further long-term randomized controlled trials are therefore needed before definite conclusions can be provided about the beneficial use of tooth block compared with bone block.

SARS-COV-2 detection in saliva and nasopharyngeal swabs using RT-PCR was similar

Abstract The World Health Organization has declared the widespread spread of SARS-CoV-2 and its associated disease (COVID-19) a public health emergency. The standard gold test for detecting the virus is the RT-PCR, performed from nasopharyngeal swab (NPS) samples. However, this test may be uncomfortable for the patient and requires specific training and attire from the health professional responsible for collecting the sample. Therefore, the search for alternative ways to collect samples that may be used in the diagnosis of COVID-19 is relevant. This study aimed to compare the results obtained from NPS and saliva samples. NPS and saliva samples were collected from 189 symptomatic outpatients suspected of COVID-19, who came to Piquet Carneiro Polyclinic. RNA extraction was performed using the Bio-Gene DNA/RNA Viral Extraction kit (Bioclin®). Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) reactions used the Molecular SARS-CoV-2 (E / RP) kit (Bio-Manguinhos). The results indicated that 142 showed a non-detectable result (ND), while 47 showed a detectable result (D). Among the 142 "ND", 137 (94.4%) saliva samples obtained the same result, while 5 samples (3.4%) were "D". Among the 47 "D" swab samples, 35 (74.4%) showed the same result in the saliva samples. The sensitivity of the saliva test was 0.74 and the specificity was 0.97. The positive predictive value was 0.88 while the negative predictive value was 0.92. The results showed that detection of Sars-CoV-2 using saliva samples showed high sensitivity and specificity compared to nasopharyngeal swabs.

Resumo A Organização Mundial da Saúde declarou a disseminação generalizada do SARS-CoV-2 e sua doença associada (COVID-19) uma emergência de saúde pública. O teste padrão ouro para detecção do vírus é o RT-PCR, realizado a partir de amostras de swab nasofaríngeo (NPS). No entanto, esse exame pode ser desconfortável para o paciente e requer treinamento específico e vestimenta do profissional de saúde responsável pela coleta da amostra. Portanto, a busca por formas alternativas de coleta de amostras que possam ser utilizadas no diagnóstico de COVID-19 é relevante. O objetivo deste estudo foi comparar os resultados obtidos em amostras de NPS e saliva. Amostras de NPS e saliva foram coletadas de 189 pacientes ambulatoriais sintomáticos com suspeita de COVID-19, que procuraram a Policlínica Piquet Carneiro. A extração de RNA foi realizada com o kit Bio-Gene DNA / RNA Viral Extraction (Bioclin®) e as reações em tempo real da reação em cadeia da polimerase-transcriptase reversa (RT-PCR) usaram o kit Molecular SARS-CoV-2 (E / RP) (Bio-Manguinhos). Os resultados indicaram que 142 apresentaram resultado não detectável (ND), enquanto 47 apresentaram resultado detectável (D). Entre os 142 "ND", 137 (94,4%) amostras de saliva obtiveram o mesmo resultado, enquanto 5 amostras (3,4%) foram "D". Dentre as 47 amostras de swab "D", 35 (74,4%) apresentaram o mesmo resultado nas amostras de saliva. A sensibilidade do teste de saliva foi de 0,74 e a especificidade foi de 0,97. O valor preditivo positivo foi de 0,88, enquanto o valor preditivo negativo foi de 0,92. Os resultados mostraram que a detecção de Sars-CoV-2 em amostras de saliva apresentou alta sensibilidade e especificidade quando comparada com swabs nasofaríngeos.

Reducing the viral load of SARS-CoV-2 in the saliva of patients with COVID-19.

OBJECTIVE: To evaluate the reduction in the salivary viral load using oral antiseptic mouthwashes in patients testing positive for COVID-19. METHODS: Sixty-three individuals were recruited after testing positive for COVID-19 by real-time RT-PCR assay and divided into 5 groups. Group 1 received sterile water, group 2 received 1.5% hydrogen peroxide solution (HP), group 3 received 0.12% chlorhexidine (CHX), group 4 received 0.1% sodium hypochlorite solution (NaClO), and group 5 received sequential rinses using CHX and HP. After collecting the initial saliva sample, individuals were asked to use the designated mouthwash for 1 min. Additional saliva samples were collected immediately after rinsing, 15, and 30 min after rinsing. Real-time RT-PCR assays for RNA detection of SARS-CoV-2 were performed on the saliva samples. RESULTS: There were no significant differences among the experimental groups and the control group in any period. Compared to the baseline values, there was a significant reduction in the number of copies of SARS-CoV-2 after 30 min in group 2 and immediately after the initial mouthwash in group 4. CONCLUSIONS: No experimental group demonstrated a significant reduction in the viral load compared to the control group.

Morphological alterations in tongue epithelial cells infected by SARS-CoV-2: A case-control study.

OBJECTIVE: The aim of the present case-control study was to evaluate the morphological aspects of the epithelial cells from the dorsum of the tongue and the expression of the SARS-CoV-2 Spike protein in these cells, in patients with and without COVID-19 infection. METHODS: 24 individuals with at least one symptom of COVID-19 were recruited among inpatients from Hospital Universitário Pedro Ernesto (Rio de Janeiro, Brazil). 14 patients who tested positive for COVID-19 by RT-PCR were included in the case group, and 10 patients who tested negative were included in the control group. Cytological smears from the dorsum of the tongue were obtained from all patients and analyzed using immunohistochemistry directed against SARS-CoV-2-Spike protein. Morphological changes in epithelial cells were analyzed using light microscopy. RESULTS: Immunohistochemistry showed that 71% of the COVID-19 patients presented epithelial cells positive for the presence of the SARS-CoV-2 Spike protein, and all cells coming from patients in the control group were negative. Cytological analysis showed significant differences when comparing epithelial cells from COVID-19-positive and COVID-19-negative patients. CONCLUSION: COVID-19 may generate dimensional changes in tongue epithelial cells; however, further studies are necessary to understand how this happens.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Compared with a Composite Grafting Material or Bone Substitute Alone: a Systematic Review and Meta-Analysis Assessing Volumetric Stability of the Grafting Material.

OBJECTIVES: Test the hypothesis of no difference in the volumetric stability of the grafting material following maxillary sinus floor augmentation with autogenous bone graft compared with composite grafting material or bone substitute alone applying the lateral window technique. MATERIAL AND METHODS: MEDLINE (PubMed), Embase, Cochrane library and hand-search of relevant journals were conducted. Human studies published in English until the 9th of October 2020 were included. Outcome measures included three-dimensional volumetric changes of the grafting material and potential predictive parameters. Volumetric changes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval. RESULTS: Electronic search and hand-searching resulted in 102 entries. Four randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. The volumetric stability of the grafting material was significantly improved by mixing autogenous bone graft with a non-resorbable xenograft compared with autogenous bone graft. Meta-analyses assessing absolute and relative volumetric changes demonstrated no significant differences between autogenous bone graft compared with allogeneic bone graft, synthetic biomaterials combined with autogenous bone graft or used alone. Association between volumetric changes of the grafting material and potential predictive parameters were not assessed in the included studies. CONCLUSIONS: Volumetric reduction of the augmented area seems inevitable following maxillary sinus floor augmentation regardless of the grafting material. The volumetric stability of autogenous bone graft is improved with addition of xenograft compared with autogenous bone graft. However, conclusions drawn from this systematic review should be interpreted with caution since only four studies using three-dimensional radiographic measurements were included.

Mouthguard use and attitudes regarding dental trauma among elite cross-country mountain biking and field hockey athletes.

BACKGROUND/AIMS: Cross-country mountain biking and field hockey are two Olympic sports that pose a potential risk for dentofacial trauma. However, mouthguard use is not mandatory in either of these sports and knowledge about tooth rescue among athletes is often neglected. The aim of this cross-sectional epidemiological survey was to evaluate the prevalence of sports-related dentofacial injuries, mouthguard use, and attitudes regarding tooth rescue among cross-country mountain biking and field hockey athletes participating at pre-Olympic competitions held in Rio de Janeiro, Brazil. MATERIALS AND METHODS: A convenience sample of 217 athletes from 33 countries participating in cross-country mountain biking (n = 82; mean age = 30.96 ± 8.52 years) and field hockey (n = 135; mean age = 19.72 ± 2.46 years) pre-Olympic competitions were examined clinically, and they answered a questionnaire regarding previous history of sports-related dentofacial injuries, attitudes toward mouthguard use, and tooth rescue. RESULTS: There were 120 (55.30%) males and 97 (44.70%) females who participated in the study. The prevalence of facial trauma was higher in mountain biking (54.88%) than in field hockey (26.66%, P < .001). Fracture was the most prevalent facial injury in mountain biking (80%), while laceration was the most prevalent in field hockey (30.55%). Extensive dental injuries occurred more often in mountain biking (47.37%) than in hockey (12.50%). The teeth most often affected were the maxillary central incisors in both mountain biking (57.89%) and field hockey (93.75%). Mouthguard use was more frequent among field hockey athletes (41.48%) than in mountain biking (1.22%, P < .001). The overall knowledge about tooth rescue was low, and most of the athletes in both sports did not know what to do in case of an avulsed tooth. CONCLUSIONS: Prevalence of dentofacial injuries among XCO-MTB and field hockey athletes participating at this pre-Olympic event was high. The majority of the athletes in this study did not use mouthguards and were unaware of recommendations in the case of an avulsed tooth.

Harvesting of Autogenous Bone Graft from the Ascending Mandibular Ramus Compared with the Chin Region: a Systematic Review and Meta-Analysis Focusing on Complications and Donor Site Morbidity.

OBJECTIVES: The aim of this systematic review was to test the hypothesis of no difference in complications and donor site morbidity following harvesting of autogenous bone graft from the ascending mandibular ramus compared with the chin region. MATERIAL AND METHODS: MEDLINE (PubMed), Embase and Cochrane Library search in combination with a hand-search of relevant journals was conducted including human studies published in English through June 26, 2020. Randomized and controlled trials were included. Outcome measures included pain, infection, mucosal dehiscence, altered sensation or vitality of adjacent tooth/teeth, neurosensory disturbances and patient-reported outcome measures. Risk of bias was assessed by Cochrane risk of bias tool and Newcastle-Ottawa Scale. RESULTS: Ten controlled trials of high-quality fulfilled inclusion criteria. Risk of infection and mucosal dehiscence seems to be comparable with the two treatment modalities. However, harvesting from the chin seems to be associated with increased risk of pain, altered sensation or loss of tooth vitality, and neurosensory disturbances. Willingness to undergo the same treatment again was reported with both treatment modalities, but significant higher satisfaction, lower discomfort and acceptance of the surgical procedure was reported following harvesting from the ascending mandibular ramus. CONCLUSIONS: The hypothesis was rejected due to higher prevalence and severity of complications and donor site morbidity following harvesting of autogenous bone graft from the chin region. Dissimilar evaluation methods and various methodological confounding factors posed serious restrictions for literature review in a quantitative systematic manner. Conclusions drawn from results of this systematic review should therefore be interpreted with caution.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Alone Compared with Alternate Grafting Materials: a Systematic Review and Meta-Analysis Focusing on Histomorphometric Outcome.

OBJECTIVES: The objective of present systematic review was to test the hypothesis of no difference in histomorphometric outcome after maxillary sinus floor augmentation with autogenous bone graft alone compared with alternate grafting materials applying the lateral window technique. MATERIAL AND METHODS: MEDLINE (PubMed), Embase and Cochrane library search in combination with hand-search of relevant journals were conducted. Human studies published in English until the 25th of March, 2020 were included. Histomorphometric outcomes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval (CI). RESULTS: Electronic search and hand-searching resulted in 1902 entries. Sixteen randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. Descriptive statistics showed comparable or improved histomorphometric outcomes with autogenous bone graft. Meta-analysis revealed a mean difference of -7.1% (CI = -11.0 to -3.2) indicating a significant higher amount of bone after maxillary sinus floor augmentation with autogenous bone graft compared with alternate grafting materials. Subgroup analysis demonstrated a non-significantly differences of -3.7% (CI = -10.9 to 3.4), -11.5% (CI = -25.9 to 2.8), 2.2% (CI = -16.9 to 21.3), and -4.6% (CI = -14.4 to 5.2), when autogenous bone graft was compared with allogeneic bone graft, xenograft, composite grafting materials involving xenograft or synthetic biomaterial mixed with autogenous bone graft, respectively. CONCLUSIONS: Maxillary sinus floor augmentation with autogenous bone graft seems to facilitate improved histomorphometric outcomes compared with alternate grafting materials. However, the included studies were characterised by an unclear risk of bias and various methodological confounding factors. Hence, the conclusions drawn from the results of present study should be interpreted with caution.

Intrasocket interventions to prevent alveolar osteitis after mandibular third molar surgery: A systematic review and network meta-analysis.

A systematic review and network meta-analysis was carried out to assess the efficacy of different intrasocket interventions immediately after mandibular third molar surgery to prevent alveolar osteitis (AO). An electronic search was undertaken using EMBASE, Cochrane Library, MEDLINE/PubMed, Web of Science, Scopus, LILACS, and grey literature. We reviewed studies published up to September 2019 and included 37 randomized controlled trials (6175 mandibular third molar surgeries in 4716 patients). The pairwise meta-analysis showed that the incidence of AO decreased significantly when an intrasocket intervention was performed (risk ratio 0.39 [0.30, 0.52]; p < 0.0001). Platelet-rich fibrin (odds ratio 0.28; 95% CI [0.10, 0.71]), chlorhexidine gel 0.2% (0.52 [0.32, 0.95]), eugenol paste (0.06 [0.00, 0.77]), recombinant bovine growth factor (0.07 [0.00, 0.97]), colloidal silver gelatin sponge (0.05 [0.00, 0.74]), and acellular dermal matrix (0.04 [0.00, 0.74]) were significantly more effective than the placebo. Platelet-rich fibrin and chlorhexidine 0.2% gel had a large number of included studies and patients per comparison. Overall, there was moderate evidence to support the use of platelet-rich fibrin or chlorhexidine 0.2% gel in the socket for the prevention of AO after mandibular third molar surgery.

Horizontal Alveolar Ridge Augmentation with Allogeneic Bone Block Graft Compared with Autogenous Bone Block Graft: a Systematic Review.

OBJECTIVES: The objective of the present systematic review was to test the hypothesis of no difference in implant treatment outcome after horizontal ridge augmentation with allogeneic bone block compared with autogenous bone block. MATERIAL AND METHODS: A MEDLINE (PubMed), Embase and Cochrane Library search in combination with a hand-search of relevant journals was conducted including human studies published in English through March 13, 2019. Comparative and non-comparative studies evaluating horizontal ridge augmentation with allogeneic bone block were included. Cochrane risk of bias tool and Newcastle-Ottawa Scale were used to evaluate risk of bias. RESULTS: One comparative study with high quality and 12 non-comparative studies fulfilled the inclusion criteria. Considerable heterogeneity prevented meta-analysis from being performed. The comparative retrospective short-term study demonstrated no significant difference in implant treatment outcome between the two treatment modalities. Non-comparative long-term studies revealed high implant survival, gain in alveolar ridge width and bone regeneration with allogeneic bone block. However, non-comparative studies disclosed high incidence of complications including dehiscence, exposure of allogeneic bone block and partial or total loss of the grafts. CONCLUSIONS: There seemed to be no difference in implant treatment outcome after horizontal ridge augmentation with allogeneic bone block compared with autogenous bone block. However, increased risk of complications was frequently reported with allogeneic bone block.

Clinical effect of Lactobacillus on the treatment of severe periodontitis and halitosis: A double-blinded, placebo-controlled, randomized clinical trial.

PURPOSE: To evaluate the clinical association between Lactobacillus and the efficacy of adjuvant treatment of severe periodontitis, periodontal parameters, and halitosis. METHODS: 60 healthy volunteers with severe periodontitis were randomized into two groups to receive periodontal therapy in a single session and lactobacillus or a placebo for 90 days. The test group received Lactobacillus reuteri, salivarius and acidophilus, and the control group received placebo with xylitol. RESULTS: There was a reduction in the depth levels of the probing pocket and the level of relative attachment after 90 days (P< 0.01). Regarding bleeding after pocket probing, the full-mouth with lactobacillus groups also showed more reduction than the placebo group (P< 0.01). The same results were observed with the halitosis parameters (P< 0.01). Oral administration of lactobacillus reduced periodontal parameters and halitosis and could contribute to the beneficial effects on periodontal conditions and halitosis. CLINICAL SIGNIFICANCE: Oral administration of lactobacillus reduced periodontal parameters and halitosis. At the dental office, dentists can consider using the beneficial effects of the probiotics on periodontal conditions and halitosis.

Maxillary Sinus Floor Augmentation With or Without Barrier Membrane Coverage of the Lateral Window: a Systematic Review and Meta-Analysis.

OBJECTIVES: Test the hypothesis of no difference in implant treatment outcomes after maxillary sinus floor augmentation with or without barrier membrane coverage of the lateral window. MATERIAL AND METHODS: A MEDLINE (PubMed), Embase and Cochrane library search in combination with a hand-search of relevant journals was conducted. Human studies published in English until the 5th of July, 2019 were included. Randomised controlled trials and controlled trials with an observation period of minimum six months were included. Primary outcomes included survival of suprastructures and implants. Secondary outcomes included implant stability quotient, peri-implant marginal bone loss, bone regeneration, patient-reported outcome measures, biologic and mechanical complications. RESULTS: The electronic search and hand-searching resulted in 1068 entries. Six randomised controlled trials characterised by low to high risk of bias and one controlled trial with high risk of bias fulfilled the inclusion criteria. High implant survival rate was reported with both treatment modalities. Meta-analyses disclosed a mean difference of newly formed bone of 6.4% (confidence interval = 0 to 12.9) and non-mineralised tissue of -1.1% (confidence interval = -2.7 to 0.5), indicating more newly formed bone and diminished non-mineralised with barrier membrane coverage. CONCLUSIONS: There seem to be no statistically significant differences in implant treatment outcomes after maxillary sinus floor augmentation with or without barrier membrane coverage of the lateral window. However, barrier membrane coverage increases percentage of newly formed bone and diminishes proliferation of non-mineralised tissue. Thus, barrier membrane coverage seems to be beneficial and also preventing displacement of the grafting material.

Histologic and Tomographic Findings of Bone Block Allografts in a 4 Years Follow-up: A Case Series.

The aim of this paper is to report histologic and tomographic findings of fresh frozen bone block allografts bearing dental implants in functional occlusion in a long-term follow-up. Four patients with implants functionally loaded for 4 years on augmented ridges requiring additional mucogingival surgery or implant placement were included in this case series. Cone-beam tomography scans were compared volumetrically between the baseline (first implant placement) and current images. Biopsies of the grafts were retrieved and sent to histological analysis. Volumetric reduction of the grafts varied from 2.1 to 7.7%. Histological evaluation demonstrated well-incorporated grafts with different degrees of remodeling. While data presented in this report are from a small sample size and do not allow definitive conclusions, the biopsies of the grafted sites were very similar to the host's native bone. Remodeling of the cortical portion of the allografts seems to take longer than the cancellous portion. The presence of unincorporated graft remains did not impair the implant success or the health of the surrounding tissues. This is the first time histologic and tomographic long term data of bone allograft have been made available in dentistry.

Histologic and Tomographic Findings of Bone Block Allografts in a 4 Years Follow-up: A Case Series

Abstract The aim of this paper is to report histologic and tomographic findings of fresh frozen bone block allografts bearing dental implants in functional occlusion in a long-term follow-up. Four patients with implants functionally loaded for 4 years on augmented ridges requiring additional mucogingival surgery or implant placement were included in this case series. Cone-beam tomography scans were compared volumetrically between the baseline (first implant placement) and current images. Biopsies of the grafts were retrieved and sent to histological analysis. Volumetric reduction of the grafts varied from 2.1 to 7.7%. Histological evaluation demonstrated well-incorporated grafts with different degrees of remodeling. While data presented in this report are from a small sample size and do not allow definitive conclusions, the biopsies of the grafted sites were very similar to the host's native bone. Remodeling of the cortical portion of the allografts seems to take longer than the cancellous portion. The presence of unincorporated graft remains did not impair the implant success or the health of the surrounding tissues. This is the first time histologic and tomographic long term data of bone allograft have been made available in dentistry.

Resumo O objetivo deste artigo é relatar achados histológicos e tomográficos de aloenxertos ósseos em bloco com implantes dentários em oclusão funcional em um acompanhamento de longo prazo. Quatro pacientes com implantes funcionalmente carregados por 4 anos em rebordos alveolares enxertados, que necessitaram de cirurgia mucogengival ou instalação de implantes adicionais foram incluídos nesta série de casos. Imagens de tomografia cone-beam foram comparados volumetricamente entre o momento inicial (instalação do implante original) e imagens atuais. Biópsias dos enxertos foram coletadas e enviadas para análise histológica. A redução volumétrica dos enxertos variou entre 2,1-7,7%. A avaliação histológica demonstrou enxertos bem incorporados com diferentes graus de remodelação. Embora os dados apresentados neste relato sejam de uma amostra pequena e não permitam conclusões definitivas, as biópsias dos sítios enxertados apresentaram características muito similares ao osso nativo. A remodelação da porção cortical dos aloenxertos parece levar mais tempo do que a porção esponjosa. A presença de remanescentes do enxerto não incorporado não demonstrou impacto no sucesso dos implantes ou na saúde dos tecidos circunjacentes. Este é o primeiro relato com dados histológicos e tomográficos em longo prazo de enxertos ósseos alógenos disponível na odontologia.

Bending Resistance and Cyclic Fatigue Life of a new Single-File Reciprocating Instrument Waveone Gold.

OBJECTIVE: The present study aimed to evaluate the bending resistance and cyclic fatigue fracture resistance of a new single-file reciprocating instrument called WaveOne Gold. Reciproc and WaveOne instruments were used as references for comparison. METHODS: Sixty 25-mm NiTi instruments (Reciproc R25, WaveOne Primary and WaveOne Gold Primary) were tested. Flexibility was determined by applying 45° bending tests using a universal testing machine (n=10). A custom-made device was used during cyclic fatigue test (n=10), comprising a stainless steel artificial canal measuring 1.4 mm in diameter, 19 mm in total length with an 86° angle and 6 mm radius of curvature. Possible deformations at the helical shaft and mode of fracture were evaluated using scanning electron microscopy analysis. Statistical analysis was performed using one-way analysis of variance. Post hoc pair-wise comparisons were performed using Tukey's test for multiple comparisons (P<0.05). RESULTS: WaveOne presented significantly higher bending resistance than the other tested systems (P<0.05), whereas Reciproc presented the lowest bending resistance (P<0.05). Reciproc revealed a significantly longer cyclic fatigue fracture resistance than the other systems (P<0.05). CONCLUSION: Although WaveOne Gold presented higher flexibility than WaveOne, no differences in the resistance to fatigue were observed between both systems. The Reciproc files were more flexible and resistant to fatigue for the angle of curvature of 86° and 6 mm radius than WaveOne and WaveOne Gold files.

Epidemiological evaluation of apical periodontitis prevalence in an urban Brazilian population.

The present study aimed to assess the prevalence of apical periodontitis (AP) in an urban Brazilian population according to gender, age group and tooth type. Data were collected from clinical files containing the medical and dental histories and periapical radiographs of 1,126 patients treated at the School of Dentistry at Universidade do Estado do Rio de Janeiro between March 2000 and December 2010. A total of 15,724 periapical radiographs were evaluated. All the radiographs were evaluated by two independent, previously calibrated endodontists (kappa = 0.88). Periapical areas on the radiographs were classified as N (normal) or AR (apical radiolucency). The frequency of AP and the 95% Confidence Interval (95%CI) were calculated according to gender, age group and tooth type. Differences between groups were calculated using the Z-test at a significance level of 5% (p < 0.05). AP was present in 7.87% of the samples, with 16.70% occurring on previously endodontically treated teeth and 44.65% occurring on teeth referred for endodontic treatment (TR-RCT). The frequency of AP was higher among females (64%) than among males (35%). The central and lateral maxillary incisors were the most frequently affected teeth. The frequency of AP was higher among individuals between 30 and 49 years of age. In this population, AP was more prevalent among females and among individuals between 30 and 49 years of age, and the central and lateral maxillary incisors were the most frequently affected teeth.

Time-dependent changes in fresh-frozen bone block grafts: tomographic, histologic, and histomorphometric findings.

BACKGROUND: Bone allografts have shown satisfactory clinical results in alveolar ridge reconstructions. However, the process of incorporation and the resorption rates of these grafts are not yet fully understood. PURPOSE: The aim of this study was to use computed tomography (CT), histology, and histomorphometry to assess the time-dependent rates of resorption and incorporation of fresh-frozen bone allografts. MATERIALS AND METHODS: Twenty-four patients underwent alveolar ridge reconstruction with bone block allografts and were randomly allocated to three groups with different graft healing periods (4, 6, or 8 months) before implant placement. To assess the resorption rates, CT scans were acquired within 7 days after bone graft surgery and at the end of the period. Graft samples were collected and sent for histological and histomorphometric analyses. RESULTS: The graft resorption mean rates were 50.78% ± 10.43, 32.77% ± 7.84, and 13.02% ± 3.86 for the 4-, 6-, and 8-month groups, respectively, and were significantly different among the three groups. Newly formed bone with osteocytes near the grafted bone was observed in all three groups. The number of osteocytes was significantly lower at 4 months. Grafted bone remains were significantly higher in the shortest period of time. All of the grafts showed large amounts of calcified tissue. CONCLUSIONS: All three groups showed new bone formation and different bone resorption rates. Graft healing periods of 4 months showed less graft resorption and seemed to be the most favorable for implant placement. Healing periods of 8 months showed the largest rate of graft resorption, which could render the grafts unfavorable for implant placement.

Epidemiological evaluation of apical periodontitis prevalence in an urban Brazilian population

The present study aimed to assess the prevalence of apical periodontitis (AP) in an urban Brazilian population according to gender, age group and tooth type. Data were collected from clinical files containing the medical and dental histories and periapical radiographs of 1,126 patients treated at the School of Dentistry at Universidade do Estado do Rio de Janeiro between March 2000 and December 2010. A total of 15,724 periapical radiographs were evaluated. All the radiographs were evaluated by two independent, previously calibrated endodontists (kappa = 0.88). Periapical areas on the radiographs were classified as N (normal) or AR (apical radiolucency). The frequency of AP and the 95% Confidence Interval (95%CI) were calculated according to gender, age group and tooth type. Differences between groups were calculated using the Z-test at a significance level of 5% (p < 0.05). AP was present in 7.87% of the samples, with 16.70% occurring on previously endodontically treated teeth and 44.65% occurring on teeth referred for endodontic treatment (TR-RCT). The frequency of AP was higher among females (64%) than among males (35%). The central and lateral maxillary incisors were the most frequently affected teeth. The frequency of AP was higher among individuals between 30 and 49 years of age. In this population, AP was more prevalent among females and among individuals between 30 and 49 years of age, and the central and lateral maxillary incisors were the most frequently affected teeth.