Brazilian Oral Research

Erratum
[This corrects the article doi: 10.1590/1807-3107bor-2023.vol37.0119].
Erratum
[This corrects the article doi: 10.1590/1807-3107bor-2024.vol38.0091].
Dental appointments in the primary health care setting for users with toothache: a longitudinal analysis
Diniz FC, Senna MIB, Silva ÉT, Silva LA, Alencar GP, Pinheiro EL, Chalub LLFH and Ferreira RC
This study aimed to estimate the morbidity associated with toothache treated in the primary health care (PHC) setting, stratified by the population size of Brazilian municipalities, from 2018 to 2022. This longitudinal ecological study was based on public national data from routine public dental service utilization records within the Health Information System for Primary Care. These data were employed to compute the rate of dental appointments for users with toothache (per 1,000 users) within each municipality throughout 15 four-month periods (P1-2018 to P3-2022), classified by population size. We integrated the databases for population size, denominator, and numerators. A longitudinal data regression model was used to estimate the four-monthly variation before and after P2-2020. Records from 5,332 municipalities (95.72%) were analyzed. The average rate of dental appointments for users with toothache (per 1,000 users) ranged from 9.65 (P2-2020) to 27.24 (P1-2018). Throughout the period, larger municipalities showed the lowest rates. Before P2-2020, the average rate in municipalities with >100,000 inhabitants fell by an average of 20.56% every four months, higher than the 7.25% variation in municipalities with < 5,000 inhabitants. After P2-2020, the rate in municipalities with < 5,000 inhabitants rose by 2.27%, a value lower than the variation in larger municipalities. The rates of dental appointments for users with toothache in the PHC setting indicate the persistent severity of dental conditions among public health service users, with variations across different regions of the country. The COVID-19 pandemic has affected the rate of dental appointments for users with toothache, underscoring the need for dental services to enhance their adaptability and responsiveness to such crises.
Perceptions of research integrity and open science practices: a survey of Brazilian dental researchers
Cenci J, Franco MC, Pereira-Cenci T, Correa MB, Helal L, Moher D, Bouter L, Huysmans MC and Cenci MS
The objective of this study was to evaluate Brazilian dental researchers' perceptions of research integrity and open science practices, as well as their perceptions of the way researchers are evaluated for promotion, hiring, and receiving grants. In a self-administered online survey, the respondents were presented with 3 questions on researcher evaluation in Brazil. Additionally, for 25 academic activities or characteristics, researchers rated their perceived importance for a) career advancement, b) science advancement, c) personal satisfaction, and d) social impact. The questionnaire was sent to a total of 2,179 dental researchers working in graduate programs in dentistry in Brazil. Multilevel regressions were performed to statistically confirm the differences between the predefined subgroups. Three hundred and fifty-five (16%) researchers completed the survey. Most respondents (96.1%) considered the current evaluation system to be flawed and indicated the need for improvement. Non-traditional activities were considered more important than traditional ones for science advancement (p < 0.01), and social impact (p < 0.01), whereas traditional activities were perceived to be more important only for career advancement (p < 0.01). Although Brazilian dental researchers recognize the value of open science and research integrity practices for science advancement and impact on society, they perceive that the current evaluation system emphasizes traditional activities, such as publishing many papers in well-recognized journals as criteria for advancing their careers.
Physicochemical properties of silicate tricalcium-based cement for use as pulp capping or repair material
Luna-Cruz SM, Aguiar BA, Fechine PBA, Duarte MAH, Vasconcelos BC and Mendonça JS
This study evaluated some physicochemical properties of an experimental tricalcium silicate-based cement (ETSC) indicated for use as pulp capping or endodontic repair material; Biodentine (BD) and White MTA-Angelus (MTA) cements served as comparators. Setting time, radiopacity, sorption, and solubility were determined according to ISO 6876/2012 and compressive strength according to ISO 9917-1/2019. pH and calcium ion release capacity were also assessed. Data were analyzed using ANOVA and Tukey tests or Kruskal-Wallis and Dunn tests with α = 0.05. BD (15') and ETSC (17.3') exhibited the shortest initial setting times, with BD (29') having the shortest final setting time; MTA showed longer times in both analyses (p < 0.05). ETSC and MTA showed the highest radiopacity (6.1 mm Al and 5.7 mm Al), while BD showed the lowest (3.0 mm Al) (p < 0.05). BD exhibited the highest compressive strength (88.8 MPa), significantly higher than the others (p < 0.05). BD presented the lowest values for sorption, 0.12% (24 h) and 0.48% (28 d), which differed significantly from MTA (p < 0.05). The lowest values for solubility were shown for ETSC, 0.26% (24 h), and BD, 0.52% (28 d), which differed significantly from MTA (p<0.05). ETSC showed the highest pH throughout all periods; significant differences were observed for MTA (3 h) and BD (24 h) (p<0.05). In the Ca2+ analysis, BD provided the highest values in all periods; differences were only significant compared to MTA (3h/24h) (p <0 .05). Considering the study conditions, it can be concluded that ETSC exhibited characteristics similar or better properties than the commercial cements tested, except for compressive strength.
Fiberglass posts reduced fractures in endodontically treated teeth restored with veneers: a case-control study
Coelho-DE-Souza FH, Conceição AAB, Erhardt MCG and Gonçalves LS
This study aimed to evaluate the effects of fiberglass posts on fracture behavior in endodontically treated teeth (ETT) restored with composite veneers. Adult patients who had endodontically treated anterior teeth restored with composite veneers, with or without fiberglass posts, were divided into the case (with fractured teeth) and control (without fractured teeth) groups. All fracture patterns were sorted by a 6-point scoring system: 0, no fracture; 1, veneer buccal fracture; 2, incisal edge fracture; 3, coronal middle-third fracture; 4, coronal cervical fracture; 5, coronal and root fracture; and 6, root fracture. The odds ratio was calculated concerning the outcome (fracture) and exposed factor (post presence). Fracture patterns were analyzed by the Mann-Whitney and Fisher exact tests, with a significance level of 95%. Of the 89 ETT restored with composite veneers (31 with posts; 58 without posts), 30 were fractured. The odds ratio revealed a reduction in fracture risk to 34% compared with ETT without posts. Teeth without posts fractured more frequently, showing more complex fracture patterns. In conclusion, fiberglass posts decreased the risk of fractures in ETT restored with composite veneers.
Surface roughness of composite resins subjected to brushing with whitening toothpastes: an in vitro study
Ferreira NMR, Lippert VF, Heck ABDS, Spohr AM, Kunrath MF, Feldens CA and Kramer PF
The emergence of toothpastes containing different abrasive and whitening substances has been a constant concern among dental professionals. The aim of the present study was to perform an in vitro assessment of the surface topography of nanoparticle composite resins subjected to simulated brushing with dentifrices. Test samples were prepared with Filtek Universal (3M ESPE), Filtek Bulkfill (3M ESPE) and Z350 (3M ESPE), with 24 samples per resin. A testing machine was used to simulate brushing with the dentifrices Colgate Total 12, Oral B 100% and Oral B Gengiva Detox Gentle Whitening (8 samples per group). The constant speed of the machine was 250 cycles per minute, and 20.000 cycles were carried out, which corresponds to 24 months (1 hour and 20 minutes). Roughness features and qualitative surface topography were investigated. Statistical analysis involved the Kruskal-Wallis, Wilcoxon and Mann-Whitney tests. A significant increase in surface roughness was found for all the resins (p < 0.05). However, no significant difference was found among the resins in terms of final roughness values (p = 0.690). In contrast, a significant difference among dentifrices was found with respect to roughness measurements (p < 0.001). The qualitative analysis revealed an increase in surface roughness in all the samples and differences in the abrasive potential of the dentifrices. In conclusion, brushing with dentifrices increases the surface roughness parameters of composite resin restorations. Moreover, the differences in the abrasive effects of the dentifrices indicate a need for further studies to establish efficacy and safety criteria.
Roughness profile and surface roughness after toothbrushing and degree of conversion of bulk-fill resins
Terada RSS, Fronza BM, Faraoni JJ, Hoshino LVC, Sato F, Palma-Dibb RG, Scheffel DLS and Giannini M
The aim of this study was to assess roughness profile and surface roughness after simulated toothbrushing cycles, as well as the degree of conversion (DC) of bulk-fill resin composites at different depths. Forty nine composite discs were made from three low-viscosity bulk-fill resins (Filtek Bulk-Fill Flowable/3M Oral Care - FBF, Beautifil-Bulk Flowable/Shofu Inc. - BBF and Surefill SDR Flow/Dentsply Caulk - SDR), three high-viscosity bulk-fill resin composites (Filtek Bulk-Fill Restorative/3M Oral Care - FBR, Beautifil-Bulk Restorative/Shofu Inc. - BBR and Tetric EvoCeram Bulk Fill/Ivoclar Vivadent - TEB) and one conventional composite (Filtek Supreme Ultra/3M Oral Care - FSU) (n=7), using addition silicon molds (2 mm thick x 10 mm diameter). The roughness profile (Rv) and surface roughness (Sa) were analyzed after 30,000 brushing cycles using confocal laser scanning microscopy. Five samples (4 mm thick x 2 mm diameter) were produced per resin composite and light-cured for 20 seconds using a LED-curing unit. After 24 hours at 37oC, DC of samples was evaluated at four depths, using a confocal Raman microscope. The data were analyzed by ANOVA and Tukey post hoc multiple-comparison tests (α = 0.05). The Rv values of FSU were lower than those obtained for BBR and BBF. The toothbrushing significantly decreased the Sa for all composites. The DC was significantly reduced at 4 mm depth. Toothbrushing changed composite surface of all materials, especially for BBR and BBF. Composites were not able to maintain the DC values shown at the top compared with those at the bottom (4 mm depth).
Thermogenic preworkout supplement induces alveolar bone loss in a rat model of tooth movement via RANK/RANKL/OPG pathway
Cavalcante GRG, Moreno MC, Pirih FQ, Soares VP, Silveira ÉJDD, Silva JSPD, Pereira HSG, Klein KP, Lopes MLDS, Araujo AA, Martins AA and Lins RDAU
The aim of this study was to investigate the effect of thermogenic supplementation on the bone tissue of rats subjected to orthodontic movement. A total of 38 male Wistar rats underwent orthodontic movement of the left permanent maxillary first molars for 21 days. The rats were assigned to three groups: Control group: water; Thermogenic 1: C4 Beta Pump thermogenic; or Thermogenic 2: PRE-HD/Pre-workout. Micro-computed tomography (micro-CT) was used to investigate the dynamic changes in the microstructure of alveolar bone during orthodontic tooth movement in rats. Histopathologic analysis was performed by hematoxylin and eosin (H&E) staining, whereas tartrate-resistant acid phosphatase (TRAP) was employed for osteoclast count. Maxillary tissue was collected and evaluated by immunohistochemistry for receptor activator of NF-κB (RANK), receptor activator of NF-κB ligand (RANKL), and osteoprotegerin (OPG). The Thermogenic 2 group exhibited a significantly lower percentage of bone volume fraction (BV/TV) (68.21% ± 17.70%) compared to the control (86.84% + 12.91%) and Thermogenic 1 groups (86.84% + 15.94%) (p < 0.05). The control group had a significantly higher mean orthodontic movement in the mesial direction (0.2143 mm + 0.1513 mm) than the Thermogenic 2 group (0.0420 mm + 0.05215 mm) (p < 0.05). The Thermogenic 2 and Thermogenic 1 groups showed a stronger immunostaining for RANKL when compared to the control group (p < 0.05). The supplementation used in the Thermogenic 2 group (PRE-HD/Pre-workout) induced alveolar bone loss in rats subjected to orthodontic movement, which can be related to the regulation of the RANK/RANKL/OPG signaling pathway. This suggests the influence of thermogenic supplements on bone metabolism seems to depend on their composition.
The influence of social networks on finding and selecting healthcare professionals
Gasparoni LM, Marcos VN, Pannuti CM and Pereira SMM
Social networks consist of a group of individuals connected by family, work, or other interests and facilitated by an online structure or platform. They are also a relatively recent and widely used marketing phenomenon that is constantly evolving. The healthcare field includes professions such as social work, biology, biomedicine, physical education, nursing, pharmacy, physiotherapy, speech therapy, medicine, veterinary medicine, nutrition, dentistry, psychology, and occupational therapy. The present study aimed to analyze the influence of social networks in the process of finding and selecting healthcare professionals. The methodology was a survey using a structured questionnaire created on Google Forms. Descriptive research was carried out with non-probabilistic convenience and snowball sampling, followed by quantitative data analysis. A total of 268 participants who signed the informed consent were included in the study. The findings revealed that the most common way to find healthcare professionals is through recommendations from friends/relatives and other professionals, followed by the use of social networks. The majority of participants used social networks to search for healthcare professionals, with Instagram being the most widely used platform. Sponsored advertisements can be an effective way to reach potential new patients. The most valued characteristics in healthcare content creators were reliability, expertise, and the ability to convey messages, with health-related explanations in an easily understandable manner being the preferred type of content. Therefore, this study revealed that social networks can influence the search for and selection of healthcare professionals.
Bond strength to eroded dentin as per chlorhexidine use for controlling erosive wear or interface aging: an 18-month assay
Farias-Neto AM, Landmayer K, Liberatti GA, Shimokawa CAK, Wang L, Honório HM, Matos AB and Francisconi-Dos-Rios LF
The aim of this study was to assess the effect of a chlorhexidine digluconate solution (CHX) applied as an antiproteolytic agent for controlling erosive tooth wear or as part of the adhesive treatment on long-term bond strength to eroded dentin. Dentin specimens were abraded with a 600-grit silicon carbide (SiC) paper for 1 min (sound dentin - S), subsequently treated with 2% CHX for 1 min (with excess removed, followed by a 6-hour rest), and eroded by exposure to Coca-Cola for 5 min, three times a day, for 5 days (CHX-treated and eroded dentin - CHXE), or only eroded (eroded dentin - E). The specimens were acid-etched (15 s), rinsed (30 s), dried (15 s), and rehydrated with 1.5 μL of distilled water for 1 min, with excess removed (control - S.C/CHXE.C/E.C) or 2% CHX (S.CHX/CHXE.CHX/E.CHX). Adper Single Bond 2 was scrubbed twice on the surface for 15 s each and then light-cured for 10 s, and resin composite cores were built up. Specimens were sectioned into beams and microtensile bond strength was tested (μTBS; 0.5 mm/min) immediately or after 18-month aging. Failure modes were analyzed using a digital microscope. Data (μTBS/MPa) were analyzed by three-way ANOVA, followed by Tukey's test (α = 0.05). μTBS to E and CHXE, irrespective of the rehydration solution and aging period, were equivalent to each other and lower than that to S. CHX as the rehydration solution reduced immediate and long-term µTBS to S. Aging reduced μTBS. By controlling tooth wear or interface aging, CHX could not influence long-term bonding to eroded dentin.
Unilateral cleft lip and palate patients present cranial base modifications: a cross-sectional study
Villoria EM, Souki BQ, Assis MAL, Oliveira DD, Azeredo TL and Soares RV
The aim of this cross-sectional study was to perform a three-dimensional (3D) assessment of the cranial base of patients with unilateral cleft lip and palate (UCLP). Cone-beam computed tomography (CBCT) scans of 52 UCLP patients (21 females and 31 males; mean age, 10.0 ± 2.12 years) were compared with the scans of 72 individuals (24 females and 48 males; mean age, 11.0 ± 2.11 years) without CLP, matched by gender and age (control group, CG). The 3D Euclidean distances of anterior cranial base (N-S), posterior cranial base (S-Ba), total cranial base (N-Ba) lengths, cranial base width (Po-Po), as well as the cranial base flexure (NSBa), were measured using open-source software ITK-SNAP and 3D Slicer. Statistical analyses were carried out with the Student's t-test at a significance level of 5%. UCLP demonstrated shorter 3D distances than CG in the N-S, S-Ba, and N-Ba cranial base lengths (p < 0.001). In comparison with female CG, female UCLP had a smaller cranial base flexure (NSBa; p = 0.020). No statistically significant differences between UCLP and CG were found for the cranial base width (Po-Po). UCLP patients presented distinct morphological cranial base characteristics in comparison with CG. These results indicate that morphological and positioning changes in the maxillary bones are not solely attributable to the cleft and/or surgical procedures.
Structural analysis of socioeconomic factors and school jet lag in traumatic dental injury among children
Bernardino VMM, Lima LCM, Neves ÉTB, Perazzo MF, Paiva SM and Granville-Garcia AF
The objective of this study was to analyze the directions by which school jet lag is associated with traumatic dental injury in children, evaluating direct and indirect effects of socioeconomic factors and sleep. A representative, population-based, cross-sectional study was conducted with 739 schoolchildren eight to ten years of age. Parents/guardians answered a sociodemographic questionnaire, the Sleep Disturbance Scale for Children and the Circadian Energy Scale. Four examiners underwent training and calibration exercises for the diagnosis of traumatic dental injury (K > 0.80) using the criteria proposed by Andreasen (2007). Descriptive analysis was followed by structural equation modeling to determine direct and indirect associations between the variables incorporated into the theoretical model. School jet lag [standardized coefficient (SC): -0.238, 95%CI: -0.390-0.087], income (SC: -0.151, 95%CI: 0.0010-0.292), and number of residents in the home (SC: -0.109, 95%CI: -0.212-0.007) were directly associated with traumatic dental injury, whereas sleep disturbances and schooling of the parents/guardians exerted an indirect effect. Sociodemographic factors and school jet lag were associated with traumatic dental injury in children eight to ten years of age.
Brazilian version of the OHIP 14 Periodontal Disease Questionnaire: cross cultural adaptation and validation
Martins-Cruz TM, Soares KH, Leal JHG, Flecha OD, Douglas-DE-Oliveira DW and Gonçalves PF
Although it is recognized that periodontal disease negatively impacts quality of life, there is no validated instrument to assess this impact in Brazil. This study aimed to translate, cross-culturally adapt, and validate the OHIP 14 PD (Oral Health Impact Profile Applied to Periodontal Diseases) for application among Brazilian patients. The original instrument was translated and validated into Brazilian Portuguese in a cross-sectional study with 110 participants recruited from a Dental School clinic. The sample was divided into two groups: 55 with periodontal disease and 55 without periodontal disease. The instrument was self-administered twice within an interval of 7 to 10 days for patients with periodontal disease. The psychometric properties of the Brazilian version were verified using internal consistency (Cronbach's α) and the reliability through the test-retest method (ICC, intraclass correlation coefficient), convergent validity (Spearman correlation), and discriminant validity (Mann-Whitney test), with p <0.05. Most of the sample consisted of women (n=69; ±40.65 years). The OHIP 14 DP - Br showed excellent internal consistency (α=0.997) and outstanding reliability using the test-retest method (ICC=0.945, p<0.001). There was a significant correlation between the scores obtained in all seven domains between this questionnaire and self-perceived gingival health (p=0.023). This study provides psychometric evidence supporting the cross-cultural validity of the OHIP 14 DP - Br version for use in Brazil.
Efficacy of in vitro antimicrobial intracanal medicaments against C. albicans and E. faecalis in primary teeth
Rêgo EF, Rosário YMRV, Gleiser R, Ferreira-Pereira A, Portela MB and Primo LG
To exclusively evaluate, in vitro, the efficacy of five intracanal medicaments against Candida albicans and Enterococcus faecalis in infected single-rooted primary teeth. Forty-three teeth were selected, out of which 42 were simultaneously contaminated with C. albicans and E. faecalis, verified by measuring the initial quantification (IQ), whereas one tooth was used as sterile control. Forty-two teeth were then randomly assigned to six groups (n = 7 teeth in each); one was the control group, while the others received calcium hydroxide (CH), camphorated paramonochlorophenol (CMCP), CH/CMCP, chlorhexidine (CHX), or iodoform paste (IP). Two samples from each group were then randomly selected and evaluated under a scanning electron microscope along with the sterile control (n = 1) for qualitative analyses (n = 13). The remaining samples (n = 30) were collected after 7 days of intracanal medicaments (final quantification - FQ) and 7 days after medicament removal (residual quantification - RQ). ANOVA and Tukey's and c2 tests (p £ 0.05) were performed for the statistical analysis. All the medicaments, except CMCP, significantly reduced the levels of C. albicans from IQ to FQ (p = 0.046). Only CHX (p = 0.000) and IP (p = 0.007) showed a significant reduction from IQ to FQ against E. faecalis. The 2% CHX and IP demonstrated a favorable performance as an intracanal medicament, with a good antimicrobial activity against C. albicans and E. faecalis.
Temporal epidemiological profile of oral potentially malignant disorders in southern Brazil
Santos NSD, Rodrigues AZ, Ferri CA, Lima TB, Laureano NK, Rados PV, Carrard VC, Hildebrand LC and Visioli F
The study aimed to investigate oral potentially malignant disorders (OPMDs) diagnosed in an Oral Pathology service in southern Brazil over a span of 56 years and to assess the factors influencing their severity and outcomes. A retrospective analysis of histopathological records from 1965 to 2021 was performed. Lesions diagnosed as leukoplakia, erythroplakia, leukoerythroplakia, or actinic cheilitis were included. Data on age, sex, race, tobacco smoking, alcohol drinking, clinical characteristics, biopsy type, and histopathological diagnosis were collected. Among 32.698 histopathological reports, 2.10% were classified as OPMD. The study included 689 specimens from 602 patients, with a predominance of cases affecting men aged over 51 years, particularly in anatomical sites considered of low risk. White lesions, with leukoplakia as the most common clinical diagnosis were observed. Over time, there was an increase in the incidence of OPMDs among females and in high-risk anatomical sites. The mean follow-up period was 30.28 ± 29.86 months, during which 9.6% of cases exhibited malignant transformation. Lesions diagnosed as leukoerythroplakia and those presenting epithelial dysplasia exhibited a higher risk of malignant transformation, particularly when located in high-risk sites. This underscores the importance of identifying clinical and microscopic features, as well as lesion's anatomical location, as crucial factors in determining the risk of malignant transformation. These findings provide valuable insights for clinicians managing OPMDs and contribute to the improvement of oral cancer prevention.
Biomimetic and protective effects of bioactive toothpastes on eroded enamel surfaces
Oliveira AFB, Nunes VRR, Cunha JLD, Forte AG, Andrade AFB, Fernandes NLS, Pereira AMBC, D'Alpino PHP and Sampaio FC
This study aimed to evaluate the effectiveness of bioactive toothpastes in remineralizing eroded enamel surfaces in vitro. Bovine enamel blocks (n = 48) were obtained and classified into untreated, demineralized, and treated areas. Specimens were randomly classified into six groups (n = 8 each): fluoride-free toothpaste (NCT), Colgate Total 12 (PCT), Sensodyne Repair and Protect (SRP), Sensodyne Pronamel (SPE), Regenerador + Sensitive (RGS), and RGS/calcium booster (RCB). The specimens were subjected to erosive pH cycling for 5 days for 4 times/day (90 s) and treated with toothpaste slurries (1:3) for 1 min. The Vickers hardness (50 g/10 s) and percentage surface hardness recovery (%SMHR) were calculated. Furthermore, the topography and roughness (Ra) of the enamel surface were evaluated using a 3D non-contact optical profilometer, along with the tooth surface loss (TSL). Data were statistically analyzed using analysis of variance or Tukey's test (significance: 5%). The %SMHR of the SRP and NCT groups were significantly lower than those of the other groups (p < 0.05). Ra was higher when the eroded area was treated with SRP and SPE (p < 0.05). Treatment with RGS, PCT, and SPE favored the recovery of the enamel surface compared with the NCT group (p < 0.05). The best TSL results were obtained with treatment with RGS, followed by PCT and SPE (p < 0.05). The RCB group showed statistically equivalent results for surface hardness recovery and TSL (p > 0.05). Conclusively, PCT and RGS toothpastes were more effective in remineralizing the enamel surface.
Oral cancer immunology: state of the art and future perspectives
Girardi FM, Schuch LF and Martins MD
Oral cancer is a multifactorial disease involving genetic, epigenetic, and environmental factors. The literature indicates that inflammatory cells at the advancing front of the tumor induce a host immune response, preventing the spread of the tumor. However, cancer cells adopt various continued strategies to circumvent this immune surveillance. The complexity of immune mechanisms suggests that there must be virtually individual patterns of anti-tumor immune responses. Due to this important interaction of cancer with the immune system, the objective of the present study was to provide an up-to-date overview of immuno-oncology focused on oral cancer, summarizing the basic immunology, the classic risk factors, immunotherapy, and future treatment and prognostic perspectives.
Comparative analysis of clinicopathological characteristics in young and elderly patients with oral squamous cell carcinoma: a retrospective study in Northeastern Brazil
Curioso PAB, Correia Neto IJ, Souza LL, Santos EM, Santos-Silva AR, Vargas PA and Lopes MA
The aim of this study was to perform a clinicopathological analysis of oral squamous cell carcinoma (OSCC) in young patients from the northeast of Brazil and compare with elderly individuals. This retrospective study reviewed 104 OSCC cases from 2000 to 2015, focusing on patients under 40 and over 60 at diagnosis. Forty-two patients under 40 years old (40.38%) and 62 patients over 60 years old (59.62%) were analyzed using descriptive statistics, chi-square, and Fisher's exact tests for clinicopathological factors, and Kaplan-Meier and Cox models for survival and prognostics. Most of the patients were male, with younger patients having lower rates of smoking (45.24%) and alcohol use (28.57%) compared to older patients (82.30% and 40.32%, respectively). Younger patients had a higher prevalence of tongue cancer and smaller tumors but faced more compromised surgical margins, perineural invasion, local recurrence, regional metastasis, distant metastasis, and second primary tumors. Statistical findings highlighted age-related differences in clinicopathological features and indicated that despite similar overall survival rates, younger patients had a poorer prognosis related to local recurrences, regional recurrences, and second tumors. Perineural invasion emerged as an independent prognostic factor. The study suggests that younger OSCC patients require personalized management strategies to address their higher risk of adverse outcomes, with an emphasis on the prognostic significance of perineural invasion.
Crystallization by microwave energy: Effects on the survival probability of lithia-based glass ceramics
Diamantino PS, Rodrigues CDS, Carvalho ABG, Tribst JPM, Riquieri H, Ramos NC, Viegas DMDCCP, Bergamo ETP, Bonfante EA and Saavedra GSFA
This study evaluated the survival probabilities of two lithia-based glass-ceramics after final crystallization in a microwave furnace using conventional crystallization as a reference. Disc-shaped samples of a lithium silicate (LS, Celtra Duo) and a lithium disilicate (LD, e.max CAD) were prepared and divided into two groups according to the crystallization method (n = 30): microwave (M) or conventional furnaces (C). The biaxial flexural strength test was used to determine the fatigue test profile and its parameters. Then, specimens were submitted to an accelerated life test (step stress) using three profile levels - mild, moderate, and aggressive - varying the load increments and the number of cycles until fracture (4 Hz). Survival data were used to calculate Weibull's beta (β) value and reliability of the assigned missions. Scanning electron microscopy was employed to analyze surface morphology, fracture characteristics, and failure patterns. Beta (β) values for the LS-C, LS-M, LD-C, and LD-M groups were 2.65, 0.25, 0.62, and 0.3, respectively. Similar reliability was observed in all groups after 50,000 cycles at 100 and 150 Mpa. At 200 Mpa, the crystallization method did not affect the reliability within LS or LD. However, LD showed greater reliability than LS when crystallized by microwave energy. Thus, microwave energy can be suggested as an alternative to the process of conventional lithia-based glass-ceramics crystallization without damaging their survival probabilities.
A 4-year follow-up of the need for orthodontic treatment using the Dental Aesthetic Index-DAI: an exploratory analysis
Vedovello SAS, Carvalho ALM, Carneiro DPA and Meneghim MC
This study aim was to evaluate the need for orthodontic treatment of mixed to permanent dentition using the Dental Aesthetic Index (DAI) in a 4-year follow-up. A longitudinal study was conducted with 353 children in the stages from mixed (T1) to permanent (T2) dentition. The need for orthodontic treatment was assessed using the DAI categorized into: DAI 1 (absence of malocclusion and orthodontic treatment need; DAI ≤ 25); DAI 2 (malocclusion is defined and elective orthodontic treatment is needed; DAI = 26 to 30); DAI 3 (severe malocclusion and a desirable orthodontic treatment need; DAI = 31 to 35) and DAI 4 (severe malocclusion and a mandatory orthodontic treatment need; DAI ≥ 36). The Bowker symmetry test was used to determine agreement in the categorization of DAI at T1 and T2, with a significance level of 5%. The results showed a significant disagreement in the need for orthodontic treatment between T1 and T2 (p<0.05). In 34.6% of children evaluated in T1, the same need for orthodontic treatment was maintained in T2. According to the DAI, in 60.8% of the children, the need decreased, and in 39.2% their need for orthodontic treatment increased. This preliminary longitudinal study using DAI, showed a decrease in malocclusion and need for orthodontic treatment as the dentition transitioned from mixed to permanent occurred. This finding has valuable implications for epidemiological data in orthodontics.