Maria Cristina Teixeira Cangussu

A fluorose dentária no Brasil: uma revisão crítica

This paper discusses dental fluorosis as a relevant public health problem, using a review of epidemiological studies published in the last 10 years on the diseases prevalence, severity, and risk factors. The results suggest that there are already more cases than expected, although few studies refer to major severity. Thus, measures are needed for the prevention and surveillance of dental fluorosis.

Analysis of magnetic resonance imaging characteristics and pain in temporomandibular joints with and without degenerative changes of the condyle

The aim of this study was to investigate temporomandibular joint (TMJ) pain and magnetic resonance imaging characteristics in 104 TMJs with and 58 without degenerative changes of the condyle, such as osteophytes, erosion, avascular necrosis, subcondral cyst and intra-articular loose bodies. TMJ images were also assessed for flattening, retropositioning and hypomobility of condyle and disc displacement. Comparison of the TMJ side-related data showed a significant relationship between disc displacement without reduction (DDwoR) and the presence of degenerative bony changes (p=0.00). Flattening, retropositioning and hypomobility of condyle showed no significant difference in relation to the presence or absence of degenerative bony changes. Retropositioning of the condyle was significantly associated to disc displacement with reduction (DDwR) (p=0.00), while condylar hypomobility was significantly more frequent in TMJ with DDwoR (p<0.05). Independent of the presence or type of DD, TMJ pain was more frequent in the presence of degenerative bony changes. When considering only DDwR, TMJ pain was significantly associated to a degenerative condition (p=0.03). When there were no degenerative bony changes, TMJ pain was significantly more frequent in DDwoR (p=0.04). Despite the present findings, the absence of symptoms in some patients with condylar bony changes suggests that the diagnosis of osteoarthritis should be established by evaluation of magnetic resonance images in association with clinical examination.

Laser-Induced Alveolar Bone Changes During Orthodontic Movement: A Histological Study on Rodents

OBJECTIVE The aim of this study was to assess by light microscopy changes in alveolar bone during orthodontic movement in rats. BACKGROUND Orthodontic movement causes both removal and deposition of bone tissue. The use of laser phototherapy (LPT) is considered an enhancement factor for bone repair. METHODS Thirty Wistar rats were divided into two groups (n = 15) and subdivided according to animal death (7,13, and 19 days). Half of the animals in each group were treated with LPT during orthodontic movement. After animal death, specimens were processed and underwent histological and semi-quantitative analyses (HE and Sirius red). RESULTS LPT-irradiated specimens showed significantly higher numbers of osteoclasts when compared with controls at both 7 (p = 0.015) and 19 (p = 0.007) days, as well as significant increases in the number of osteoblasts (p = 0.015) between days 7 and 13. The amount of collagen matrix was significantly reduced between days 7 and 13 at both pressure and tension sites in controls (p = 0.015) but not in LPT-treated animals. LPT-treated subjects showed significantly greater deposition of collagen matrix at the pressure site at both the thirteenth (p = 0.007) and nineteenth days (p = 0.001). At the tension site, a significant increase in the amount of collagen matrix was observed in non-irradiated specimens (p = 0.048) between days 7 and 19. CONCLUSIONS LPT caused significant histological changes in the alveolar bone during induced tooth movement, including alterations in the number of both osteoclasts and osteoblasts and in collagen deposition in both pressure and tension areas.

Effect of LED Phototherapy of Three Distinct Wavelengths on Fibroblasts on Wound Healing: A Histological Study in a Rodent Model

AIM The aim of the present investigation was to evaluate histologically fibroblastic proliferation on dorsal cutaneous wounds in a rodent model treated or not with light-emitting diodes (LEDs) of three wavelengths. BACKGROUND Fibroblasts secrete substances essential for wound healing. There are few reports of LED phototherapy on fibroblast proliferation, mainly in vivo. ANIMALS AND METHODS Following approval by the Animal Experimentation Committee of the School of Dentistry of the Federal University of Bahia, we obtained 16 young adult male Wistar rats weighing between 200 and 250 g. Under general anesthesia, one excisional wound was created on the dorsum of each animal; they were then randomly distributed into four groups of four animals each: G0, untreated control; G1, red LED (700 +/- 20 nm, 15 mW, 10 J/cm(2)); G2, green LED (530 +/- 20 nm, 8 mW, 10 J/cm(2)); and G3, blue LED (460 +/- 20 nm, 22 mW, 10 J/cm(2)). The irradiation started immediately after surgery and was repeated every other day for 7 days. Animals were killed 8 days after surgery. The specimens were removed, routinely processed to wax, cut, and stained with hematoxylin/eosin (HE). Fibroblasts were scored by measuring the percentage of these cells occupying the area corresponding to wound healing on stained sections. RESULTS The quantitative results showed that red LED (700 +/- 20 nm) and green LED (530 +/- 20 nm) showed a significant increase in fibroblast numbers (p < 0.01 and p = 0.02) when compared with the control group. CONCLUSION The use of green and red LED light is effective in increasing fibroblastic proliferation on rodents.

Cárie dentária em escolares de 12 e 15 anos de escolas públicas e privadas de Salvador, Bahia, Brasil, em 2001

The aim of this paper was to assess the caries experience of 12- and 15-year-old schoolchildren from public and private schools in Salvador, Bahia, Brazil, and to identify the access of children to dental services and the coverage of such services, which might be related to differences between the groups. Cross-sectional data were obtained from 3,313 clinical exams, which followed the WHO (1997) criteria for the diagnosis of dental caries. The analysis was carried out by means of the Students t test, the chi-square test and analysis of covariance. There were no differences regarding DMFT and frequency of caries-free individuals between public and private schools. However, while F (filled teeth) was the most prevalent component of the index in subjects from private schools, M (missing teeth) was the most common in those from public schools. The access to dental services in the last year was the only variable associated to the differences between both groups. Thus, the importance of access to dental services and social benefits must be pointed out in order to guarantee equity in oral health.

Effects of laser photherapy on bone defects grafted with mineral trioxide aggregate, bone morphogenetic proteins, and guided bone regeneration: A Raman spectroscopic study

We have used Raman analysis to assess bone healing on different models. Benefits on the isolated or combined use of mineral trioxide aggregate, bone morphogenetic proteins, guided bone regeneration and laser on bone repair have been reported, but not their combination. We studied peaks of hydroxyapatite and CH groups on defects grafted with MTA, treated or not with laser, BMPs, and GBR. Ninety rats were divided in 10 groups each, subdivided into three subgroups. Laser (λ850 nm) was applied at every other day for 2 weeks. Raman readings were taken at the surface of the defect. Statistical analysis (CHA) showed significant differences between all groups (p = 0.001) and between Group II and all other (p < 0.001), but not with Group X (p = 0.09). At day 21 differences were seen between all groups (p = 0.031) and between Groups VIII and X when compared with Groups VI (p = 0.03), V (p < 0.001), IV (p < 0.001), and IX (p = 0.04). At the end of the experimental period no significant differences were seen. On regards CH, significant differences were seen at the 15(th) day (p = 0.002) and between Group II and all other groups (p < 0.0001) but not with control. Advanced maturation on irradiated bone is because of increased secretion of calcium hydroxyapatite (CHA) that is indicative of greater calcification and resistance of the bone. We conclude that the association of the MTA with laser phototherapy (LPT) and/or not with GBR resulted in a better bone repair. The use of the MTA associated to IR LPT resulted in a more advanced and quality bone repair.

The effect of the association of near infrared laser therapy, bone morphogenetic proteins, and guided bone regeneration on tibial fractures treated with internal rigid fixation: a Raman spectroscopic study

Fractures have different etiology and treatment and may be associated or not to bone losses. Laser light has been shown to improve bone healing. We aimed to assess, through Raman spectroscopy, the level of CHA (approximately 958 cm(-1)) on complete fractures animals treated with IRF treated or not with Low Level Laser Therapy-LLLT and associated or not to BMPs and GBR. Complete tibial fractures were created on 15 animals that were divided into five groups. LLLT (Laser Unit, Kondortech, São Carlos, SP, Brazil, lambda790 nm, 4 J/cm(2)/point, 40 mW, phi approximately 0.5 cm(2), 16 J/cm(2) session) started immediately after surgery and repeated at 48 h interval (2 weeks). Animal death occurred after 30 days. Raman spectroscopy was performed at the surface of the fracture. Our results showed significant differences between the groups IRF + BL /IRF_NBL (p = 0.05); between all experimental groups and untreated bone; bone/IRF + BL; IRF + BL + Bio + GBR; IRF + BL + LLLT; IRF + BL + Bio + GBR + LLLT; IRF_NBL (p < 0.001, all); IRF_NBL/IRF + BL + LLLT (p = 0.03); IRF_NBL/IRF + BL + Bio + GBR + LLLT (p = 0.02); IRF + BL/IRF + BL + LLLT (p = 0.04); IRF + BL/IRF + BL + Bio + GBR + LLLT (p = 0.002); IRF + BL + Bio + GBR/IRF + BL + Bio + GBR + LLLT (p = 0.05). It is concluded that the use of NIR LLLT associated to BMPs and GBR was effective in improving bone healing on fractured bones due to increased levels of CHA.

Maternal breastfeeding, parafunctional oral habits and malocclusion in adolescents: a multivariate analysis.

OBJECTIVE Malocclusion may result in esthetic impairment and functional disorders such as bad chewing, speech and swallowing, with a negative impact on quality of life. There is uncertainty regarding the effects of breastfeeding on dentofacial malocclusions. The purpose of the study was to evaluate the relationship between maternal breastfeeding and dental malocclusions and facial characteristics in adolescents with permanent dentition. METHODS Probabilistic sampling of 2060 12- to 15-year-old students in a cross-sectional study was used. Malocclusion, as defined by Angle, and facial characteristics were the dependent variables. The duration of breastfeeding was the main independent variable. Other covariates were tested as effect modifiers or confounders. The associations were estimated using the odds ratio (OR) in multinomial logistic regression analysis (α=5%). RESULTS There was an association between a short duration of breastfeeding (less than 6 months) and Angle class II (OR=3.14; 95% CI: 1.28-7.66) and class III (OR=2.78; 95% CI: 1.21-6.36) malocclusion only in students with a prolonged history of bruxism. A higher occurrence of severe convex profile (OR=3.4; 95% CI: 0.63-18.26) and a lower occurrence of cancave profile (OR=0.43; 95% CI: 0.21-0.88) were also observed only among adolescents who had been breastfed for a short period and exposed to a long periods of mouth breathing. CONCLUSIONS These findings support the hypothesis that breastfeeding alone seems not to be directly associated with malocclusions, but it may have a synergetic effect with parafunctional oral habits on the development of occlusofacial problems. It is recommended that deleterious oral habits be avoided, especially by children who were breast-fed for less than 6 months.

Influence of the Combination of Infrared and Red Laser Light on the Healing of Cutaneous Wounds Infected by Staphylococcus aureus

AIM We aimed to assess the use of two wavelengths on the healing of infected wounds. BACKGROUND Infection is the most significant cause of impaired wound repair or healing. Several therapeutic approaches are used for improving wound healing including the use of different light sources, such as the laser. Some wavelengths yield positive photobiological effects on the healing process. MATERIAL AND METHODS The backs of 24 young adult male Wistar rats under general anesthesia were shaved and cleaned, and a 1 by 1 cm cutaneous wound was created with a scalpel and left untreated. The wounds were infected with Staphylococcus aureus, and the rats were randomly divided into two sets of four subgroups with three animals in each subgroup: control, red laser light, infrared laser light, and red + infrared laser light. Laser phototherapy was carried out with a diode [λ680 nm/790 nm, power (P) = 30 mW/40 mW, continuous wave laser, Ø = 3 mm, power density (P) = 424 and 566 mW/cm(2), time = 11.8/8.8 sec, E = 0.35 J] and started immediately after surgery and repeated every other day for 7 d. Laser light was applied on four points around the wounded area (5 J/cm(2)). The animals were killed either 8 or 15 d after contamination. Specimens were taken, embedded in paraffin, and sectioned and stained for histological analysis. RESULTS Histological analysis showed that control subjects had a lower amount of blood vessels when compared with irradiated subjects. Irradiated subjects had more advanced resolution of inflammation compared with controls. Irradiated subjects also showed a more intense expression of the collagen matrix. The collagen fibers were mostly mature and well organized in these subjects at the end of the experimental time especially when both wavelengths were used. CONCLUSION The results of the present study indicate that laser phototherapy has a positive effect on the healing of infected wounds, particularly with the association of λ680 + λ790 nm.

Malocclusion and deleterious oral habits among adolescents in a developing area in northeastern Brazil

Although malocclusions represent a serious public health issue, there is insufficient information about this problem in adolescents in Brazil, especially in poorer areas. The purpose of this cross-sectional study was to estimate the prevalence of facial alterations, dental malocclusions, and deleterious oral habits (DOH) among adolescents in a developing area in northeastern Brazil and to test the hypothesis that the occurrence of DOH in infancy is associated with DOH during adolescence. The study included a probabilistic population-based sample of 2,060 Brazilian students aged 12-15 years. Facial characteristics (type of facial profile, facial symmetry, and passive lip sealing) and malocclusions (Angle and Dental Aesthetic Index, DAI) were evaluated. DOH in infancy and adolescence were evaluated by interviews with the parents and adolescents. Most adolescents presented with normal facial characteristics. The malocclusion prevalence (Angle) was 83%. The DAI ranged from 13 to 69 (mean ± SD: 25.9 ± 7.7). Orthodontic treatment was necessary in 45.1% of the sample. The most prevalent DOH in adolescents were nail biting, object biting, cheek/lip biting, and bruxism, which were associated with finger sucking during infancy (P < 0.05). We conclude that malocclusions and DOH are common among Brazilian adolescents and that finger sucking during infancy may be a good predictor of DOH occurrence during adolescence.