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BACKGROUND: The chronic systemic inflammatory response in periodontitis may be a potential risk factor for dementia, especially in adults. This study determined the association between periodontal treatment and dementia in adults and evaluated the effect of regular scaling treatment on the risk of dementia in this population. METHODS: This case-control study identified 18,930 patients with a dementia-related diagnosis from the Taiwan National Health Insurance Research Database. Scaling and periodontal emergency treatments were evaluated after 1 year and 3 years. Using multivariable logistic regression analysis to evaluate the association between periodontal emergency treatment and dementia risk. RESULTS: The results showed that scaling treatment rates were lower in the dementia cohort than the non-dementia cohort after 1 and 3 years. Patients who received periodontal emergency treatment within 3 years had a significantly increased risk of dementia. Furthermore, patients with periodontitis who did not receive scaling treatment within 3 years had a higher risk of dementia than patients without periodontitis (OR, 1.22; 95% CI, 1.10-1.35). CONCLUSION: This study demonstrated that periodontitis and dementia are associated, and that periodontitis is a risk factor for dementia in adults. The risk of dementia was dependent on the periodontal health status of adults, and our findings suggest that regular scaling can reduce the incidence of dementia in adults. Therefore, regular and routine scaling treatment is suggested for adults.
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Periodontite Crônica , Demência , Periodontite , Adulto , Humanos , Estudos de Casos e Controles , Raspagem Dentária , Periodontite/complicações , Periodontite/epidemiologia , Periodontite/terapia , Assistência Odontológica , Demência/complicações , Demência/epidemiologia , Periodontite Crônica/terapiaRESUMO
BACKGROUND/PURPOSE: The treatment effect of myofunctional appliance therapy has remained debated. The aim of this study was to evaluate the skeletal and dentoalveolar effects in class II division I pediatric patients receiving Education Fonctionnelle (EF) myofunctional appliance therapy. METHODS: Thirteen patients undergoing EF appliance treatment (9 boys and 4 girlsï¼average 9.3years old) met the inclusion criteria and 13 untreated patients (9 boys and 4 girlsï¼average 9.9 years old) served as controls. Initial and one-year follow-up lateral cephalometric measurement was used to assess skeletal and dentoalveolar changes. Gender ratio was analyzed using Chi-square test. Age and cephalometric measurement changes within and between the two groups were analyzed using Mann-Whitney U test and Wilcoxon signed rank test and Benjamini - Hochberg procedure. RESULTS: There were no significant differences in age, gender ratio, and initial cephalometric measurement data between the two groups. One-year follow-up skeletal findings revealed no significant differences between the two groups. Regarding the dentoalveolar changes, only the values of the upper incisor angle related parameters revealed significances between the two group (with adjusted p value). CONCLUSION: In this preliminary small sample size study, the EF group demonstrated significant upper incisor angle decrease, lower incisor angle increase, and lower incisor tip to mandibular plane distance decrease in comparison to the values measured in the control group. However, only the upper incisor angle changes were statistically significant after p-value adjustment. The skeletal effect of the EF appliance could not be verified in one-year follow-up of cephalometric data.
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Má Oclusão Classe II de Angle , Aparelhos Ortodônticos Funcionais , Cefalometria , Criança , Feminino , Humanos , Masculino , Má Oclusão Classe II de Angle/terapia , Mandíbula , Maxila , Resultado do TratamentoRESUMO
There are many studies and reviews of the relationship between the asthma disease in young individuals on the one hand and caries and dental erosion on the other. The causes of caries and dental erosion might be related to the asthmatic drugs, low pH and the sweeteners that the inhaled drug contains and perhaps even the lifestyle of children and adolescents with asthma. The main focus of this review is therefore to describe various preventive strategies, based on long experience of preventive dental care in Sweden. Two fact boxes are presented, one on fluoride toothpaste as a population-based intervention for different ages and one on diet counselling in children and adolescents with asthma. The most important thing is to introduce fluoride toothpaste early in the child's life and that the parents brush the child's teeth twice a day, in the morning after breakfast and at night before bedtime, up to the age of 10. Moreover, a high-risk approach with an additional fluoride supply at home is presented, together with the application of fluoride varnish at the clinic. Regarding diet counselling, it is important to make sure that the child has regular meals during the day, maximum five to six times a day, to allow the teeth to rest between meals and restrict sweets and soft drinks to once a week. It is important to identify children and adolescents with asthma as early as possible and to refer them to a dental team for preventive treatment.
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BACKGROUND/PURPOSE: The efficient rapid sintering technique has employed to dental zirconia ceramics for shortening the fabrication time of zirconia restorations. The purpose was to compare the optical properties of two generations of rapid sintered translucent zirconia using two dental colorimeters. MATERIALS AND METHODS: Two generations of translucent zirconia ceramics, 3 mol% yttria-tetragonal zirconia polycrystal (3Y-TZP): Copran Zr-i Ultra-T (UT) and Cercon HT (HT), and 5 mol% yttria-tetragonal zirconia polycrystal (5Y-TZP): Cercon xt (XT), of different thicknesses (0.5, 0.8, and 1.2 mm; n = 5) underwent rapid sintering (RS) or conventional sintering (CS). The CIELAB values were measured on the white and black backgrounds, respectively, by digital colorimeters, shadepilot, DeguDent (DD) and Easyshade V, Vita (Vita). Translucency parameter (TP), color difference (ΔE), surface morphology, and surface roughness were evaluated. RESULTS: RS resulted in reduced lightness, except in the XT group. The chromaticity increased slightly after RS. Translucency decreased with increasing material thickness. ΔE values differed between both sintering processes but were clinically acceptable (ΔE < 5). Grain size of XT decreased after RS. RS did not affect the surface roughness. CONCLUSION: RS is a feasible method for shortening the manufacturing time of zirconia restorations. A significant difference in TP value was only in the XT group between both sintering methods as measured on DD. Color differences in rapid sintered translucent zirconia materials are imperceptible and acceptable. The specimen thickness affected more in the TP values of Vita than DD. DD has higher sensitivity to translucency and color compared with Vita.
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Background/purpose: The bond strength and durability of highly translucent zirconia ceramics to dentin is still unclear. The purpose of this study was to investigate the effect of various surface treatments on the bond strength of self-adhesive resin cements to high-translucent zirconia crowns and dentin. Materials and methods: A high-transparent zirconia and three self-adhesive resin cements (G-CEM LinkAce (GCL), RelyX U200 (RXU) and TotalCem (TTC)) were used. The zirconia surface was sandblasted with 50 µm alumina particles or coated with an SR Link primer, while a dentin primer (Tetric N-Bond Universal, TBU) was applied to the surface of the dentin. By using three self-adhesive resin cements, zirconia samples were bonded to the dentin surfaces of human teeth. The shear strength of the specimens was measured before and after 10,000-cycle thermocycling or 90-day aging. Results: When using GCL to bond with the untreated dentin and various zirconia surfaces, the shear bond strength of the sandblasted (ZSB) and RS Link primer-coated (ZLK) groups was significantly higher than that of the untreated control group (Zc). However, in the case of TBU-treated dentin, the shear strength of the ZSB + LK + DTBU group was significantly higher than that of the other groups. After thermocycling and aging, the shear strength of the ZSB + LK + DTBU group using GCL and RXU cements decreased slightly, while the TTC showed no impact. Conclusion: The zirconia surface pretreated by sandblasting and bonding agent, which was sequentially bonded with a primer-treated dentin by using resin cements, can provide excellent shear bond strength and anti-aging performance.
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BACKGROUND: Adverse pregnancy outcomes (APOs) are associated with periodontal disease owing to the induction of a chronic systemic inflammatory response. Hence, knowledge of periodontal status during pregnancy is important in order to reduce the risk of APOs. The aim of this study was to compare the risk of APOs in women with and without periodontal disease to ascertain whether regular scaling performed prior to pregnancy improves the risk of APOs. METHOD: This case-control study enrolled1,386,887 pregnant women from the National Health Insurance Research Database who gave birth to their first child between 1 January 2004 and 31 December 2014. The study population included mothers who gave birth to low birth weight (LBW) and non-LBW newborns, totaling 86,958 and 1,299,929, respectively. Scaling and periodontal emergency treatment during and before pregnancy were assessed. Univariable and multivariable logistic regression analyses were performed to identify the associations between periodontal treatment and LBW risk. RESULTS: Compared with the comparison cohort, the pregnant women who didnot have periodontal emergency treatment or scaling treatment during pregnancy exhibited a significantly increased risk of LBW than those who had treatment. Women who underwent scaling within the2 years before pregnancy or during pregnancy had a lower risk of delivering a LBW baby (odds ratio (OR), 0.93; 95% confidence interval (CI), 0.91-0.94). In the normal group, the mothers who had periodontal emergency treatment within the2 years before pregnancy or during pregnancy had a higher risk of delivering a LBW baby (OR, 1.05; 95% CI, 1.02-1.08). In those who had scaling treatment, a lower risk of delivering a LBW baby was noted (OR, 0.95; 95% CI, 0.93-0.97). CONCLUSION: The risk of LBW was significantly increased in women who underwent periodontal treatment, and our findings suggested that periodontal disease is an important risk factor for preterm LBW babies in an East Asian population.
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BACKGROUND/PURPOSE: This study aimed to determine the correlation between the occurrence of three-rooted deciduous mandibular second molars and three-rooted permanent mandibular first molars in children. MATERIALS AND METHODS: Orthopantograms (nâ¯=â¯977) obtained from August 2008 to December 2010 were retrospectively screened and examined. Among the 977 orthopantograms, those of 591 participants (314 boys and 277 girls; mean age, 8.7 years) with bilateral deciduous mandibular second molars and permanent mandibular first molars were studied. The gender predilection and prevalence of three-rooted mandibular molars were assessed, and the pattern of concurrence was investigated. RESULTS: The prevalence of three roots were 28.4% and 27.6% in the deciduous mandibular second molars and permanent mandibular first molars, respectively. Bilateral occurrence of three-rooted mandibular molars was almost 60% for both deciduous and permanent molars. There was a significantly greater prevalence of three-rooted mandibular molars on the right side of the mandible than that on the left side. CONCLUSION: Deciduous and permanent molars show a similar prevalence of three roots. The presence of three-rooted deciduous mandibular second molar can strongly predict the possibility of three roots in permanent mandibular first molar.
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BACKGROUND/PURPOSE: Ceramic restorations have been increasingly applied over recent years. But the performance of cement is still unknown after cementation. This study was aimed to compare the compressive strength and the performances of three different types of composite resin after lithium disilicate inlay cementation. MATERIALS AND METHODS: Twenty-four human maxillary premolars were embedded in resin blocks, finished a MOD inlay preparation and scanned with an extraoral scanner. Lithium disilicate ceramic inlays (IPS e.max, Ivoclar Vivadent, Liechtenstein) were fabricated according to the scanner's model. All the specimens were then etched, bonded, and cemented with three different composite resins. Right after 5000 thermal cyclings, the specimens were accepted compressive tests to evaluate the compressive strength and failure types. Moreover, the fracture fragments of the specimens were examined using scanning electron microscopy (SEM) to verify the fracture type. RESULTS: Dual-cured resin cement (Rely X Ultimate) showed the highest compressive strength (1002⯱â¯508â¯N), followed by the light-cured flowable resin (Z350 XT) (971⯱â¯209â¯N) and light-cured bulkfill (Filtek Bulkfill) resin (581⯱â¯191â¯N). Type IV (root fracture) failures in the dual-cured resin cement group was 25%, and light-cured flowable resin was 37.5%. But none of type IV fracture was found in the light-cured bulkfill flowable group. CONCLUSION: Dual-cured resin cement demonstrates the highest compressive strength after ceramic inlay cementation. Light-cured bulkfill resin shows the lowest compressive strength, but catastrophic failure is absent in this group.
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BACKGROUND/PURPOSE: Knowledge of root canal anatomy is important for dental practice and for identifying features of anthropological significance. Three-rooted permanent mandibular molars are considered an anatomical variant of the Mongoloid race. This study aimed to determine the prevalence of three-rooted primary mandibular first molars in Taiwanese subjects. METHODS: Vertical bite-wing radiographs of 227 subjects, which had been obtained previously in the Department of Pediatric Dentistry, Taichung Veterans General Hospital, Taichung, Taiwan, from January 2004 to December 2007, were screened retrospectively. Images of 121 subjects [54 boys and 67 girls; mean age (range), 5.8 (2.4-10.4) years] who had bilateral primary mandibular first molars were studied. The sex, symmetry and frequency of occurrence of three-rooted primary mandibular first molars were recorded and statistically analyzed. RESULTS: The overall prevalence of subjects with three-rooted primary mandibular first molars was 5.0% (6/121), and 83.0% of the molars were unilateral. The prevalence of teeth that showed an extra root among all teeth examined was 2.9% (7/242). Such prevalence did not differ significantly between the right and left sides of the mandible, bilateral and unilateral, or with sex. CONCLUSION: The data presented here indicate that approximately 5% of Taiwanese subjects had a threerooted mandibular primary first molar and 80% of such teeth occurred unilaterally. Dentists should take into account the prevalence of these three-rooted variants in primary mandibular first molars among Taiwanese patients during their daily endodontic and exodontic procedures.
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Dente Molar/anatomia & histologia , Raiz Dentária/anatomia & histologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Mandíbula , Dente Molar/diagnóstico por imagem , Prevalência , Radiografia Interproximal , Estudos Retrospectivos , Fatores Sexuais , Taiwan/epidemiologia , Raiz Dentária/diagnóstico por imagemRESUMO
PURPOSE: The purpose of this study was to determine the prevalence of 3-rooted primary mandibular second molar teeth in Chinese patients via vertical bitewing radiography. METHODS: Vertical bitewing radiographs of 227 patients previously obtained from the Department of Pediatric Dentistry, Taichung Veterans General Hospital, Taichung City, Taiwan, from June 2004 to July 2007 were retrospectively screened and examined. Images of 185 patients (92 boys and 93 girls; mean age=5.6 [range=2.5-11.9] years old) with bilateral primary mandibular second molars were studied. The gender, symmetry, and frequencies of occurrence of 3-rooted primary mandibular second molars were compared. RESULTS: Eighteen (9%) 3-rooted primary mandibular second molars were found in the 185 patients, with a bilateral incidence of a symmetrical distribution of 28% (5/18). The prevalence of 3-rooted primary second molars did not differ significantly between the mandible's right and left sides (P<.41), or with gender (P<.31). CONCLUSIONS: The data presented here indicate that approximately one tenth of Chinese individuals have a 3-rooted primary mandibular second molar and that this condition is bilaterally symmetric in approximately one third of such individuals in a Taiwan hospital.
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Dente Molar/anormalidades , Raiz Dentária/anormalidades , Dente Decíduo/anormalidades , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Masculino , Mandíbula , Prevalência , Radiografia Interproximal/estatística & dados numéricos , Estudos Retrospectivos , Fatores SexuaisRESUMO
BACKGROUND/PURPOSE: Diode laser is widely used in dentistry, especially on treating soft tissues. Currently neither the effect of diode laser pulpotomy nor its comparison with formocresol (FC) pulpotomy has been fully investigated. Therefore the purpose of this study was to investigate the clinical and radiographic outcomes of diode laser pulpotomy and formocresol pulpotomy on human primary molars. MATERIALS AND METHODS: Healthy two-to eight-year-olds were treated with pulpotomies on primary molars as part of their regular dental treatment. The pulpotomy teeth were randomly assigned into one of two groups. The experimental group was treated with diode laser; the control group was treated with 1:5 dilution FC. RESULTS: Forty-five teeth with diode laser and 45 teeth with FC in 70 healthy children were studied. In 12 months follow-up, the clinical success rates were 92.9%, and 90.9% for laser and FC respectively, and the radiographic success rates were 78.6%, and 72.7% for laser and FC respectively. Conclusion: There is no significant difference of clinical and radiographic success rate between diode laser and FC pulpotomy in human primary molars followed for 12 months.
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BACKGROUND/PURPOSE: Asthma is a common, chronic disease that causes respiratory symptoms in children. Dental caries is also a common chronic disease in the pediatric population. Therefore, the aim of the present study was to investigate the correlation between asthma medications and dental caries among children in Taiwan. MATERIALS AND METHODS: The Taiwan National Health Insurance Research Database was used in this retrospective cohort study to analyze the correlation between asthma and dental caries in children. The prevalence and severity of caries were compared between children with and without asthma. The effects of different asthma medications on dental caries were also compared. RESULTS: A total of 4601 children with asthma and 4589 children without asthma were included in this study. The caries prevalence of children without asthma was 85.2%, and that of children with asthma was 90.0%. The prevalence of caries in children with asthma was significantly higher than that in children without asthma (Pâ¯<â¯0.001). The caries status was categorized into mild, moderate and severe dental caries. The rate of mild dental caries was higher in the children without asthma (35.1%) than in the children with asthma (29.8%). The rate of severe caries was significantly higher in children with asthma (34.3%) than in those without asthma (30.7%). Also, children with asthma using bronchodilators had a higher rate of severe dental caries (39%) than in children without asthma (30.7%). CONCLUSION: Children receiving asthma medications had higher dental caries prevalence and higher rate of severe caries than children without asthma.
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BACKGROUND/PURPOSE: Mutans streptococci (MS) and lactobacilli (LB) are associated with dental caries, but the acquisition of these organisms in young children with early childhood caries (ECC) and severe early childhood caries (S-ECC) has only been partly described. The purpose of this study was to evaluate the salivary MS and LB levels of preschool children with ECC and S-ECC, and the correlation of MS, LB levels with caries severity. MATERIALS AND METHODS: The study population was comprised of children from 3 to 6 years of age who visited the Pediatric Dental clinic of TCVGH. Oral examinations were performed, and whole unstimulated salivary samples were collected for buffer capacity, MS and LB counts by using commercially available diagnostic kits (CRT bacteria kit). The participants were divided into mild (dmftâ¯<â¯6), moderate (dmft:6-9) and severe caries (dmftâ¯>â¯9) groups; the salivary microbiological tests and buffer capacity were compared. RESULTS: A total of 72 children with a mean age of 4.5 years participated in this study. The salivary test showed that the higher the salivary MS level the more severe the caries status in children (Pâ¯=â¯0.001). There was also a tendency toward a higher salivary LB level in children with more severe caries, but the difference was not significant (Pâ¯=â¯0.088). There was no significant correlation between buffer capacity and caries status. CONCLUSION: The salivary MS level in preschool children was significantly correlated with the severity of early childhood caries.
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Ti-24Nb-4Zr-8Sn (Ti2448), a new ß-type Ti alloy, consists of nontoxic elements and exhibits a low uniaxial tensile elastic modulus of approximately 45 GPa for biomedical implant applications. Nevertheless, the bio-corrosion resistance and biocompatibility of Ti2448 alloys must be improved for long-term clinical use. In this study, a rapid electrochemical anodization treatment was used on Ti2448 alloys to enhance the bio-corrosion resistance and bone cell responses by altering the surface characteristics. The proposed anodization process produces a unique hybrid oxide layer (thickness 50-120 nm) comprising a mesoporous outer section and a dense inner section. Experiment results show that the dense inner section enhances the bio-corrosion resistance. Moreover, the mesoporous surface topography, which is on a similar scale as various biological species, improves the wettability, protein adsorption, focal adhesion complex formation and bone cell differentiation. Outside-in signals can be triggered through the interaction of integrins with the mesoporous topography to form the focal adhesion complex and to further induce osteogenic differentiation pathway. These results demonstrate that the proposed electrochemical anodization process for Ti2448 alloys with a low uniaxial tensile elastic modulus has the potential for biomedical implant applications.
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Ligas , Fenômenos Bioquímicos , Materiais Biocompatíveis/química , Corrosão , Osteócitos/fisiologia , Adsorção , Ligas/análise , Ligas/química , Materiais Biocompatíveis/análise , Adesão Celular , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Proteínas/química , Propriedades de SuperfícieRESUMO
The purpose of this study was to compare the effects of Nd:YAG laser pulpotomy to formocresol pulpotomy on human primary teeth. Patients with a primary tooth that required pulpotomy because of pulpal exposure to caries, were selected for this study. After removal of coronal pulpal tissue, Nd:YAG laser at 2 W, 20 Hz, 100 mJ or a 1:5 dilution of formocresol was introduced into the canal orifice for complete hemostasis. IRM paste was then placed over the pulp stump, and the tooth was restored either with composite resin or stainless steel crown. Sixty-eight teeth were treated with Nd:YAG laser and followed up for 6 to 64 months. Clinical success was achieved in 66 out of the 68 teeth (97 %), and 94.1 % were radiographically successful. In the control group, 69 primary molars were treated with formocresol and followed up for 9 to 66 months; 85.5 and 78.3% achieved clinical and radiographic success, respectively. The success rate of Nd:YAG laser pulpotomy was significantly higher than that of formocresol pulpotomy. The permanent successors of the laser-treated teeth erupted without any complications.
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Terapia a Laser , Pulpotomia/métodos , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Falha de Restauração Dentária , Formocresóis , Humanos , Metilmetacrilatos , Dente Molar , Neodímio , Materiais Restauradores do Canal Radicular , Análise de Sobrevida , Dente Decíduo , Resultado do Tratamento , Cimento de Óxido de Zinco e EugenolRESUMO
OBJECTIVES: The purpose of this study was to identify the optimal laser energy range of Er:YAG laser irradiation for laser-induced caries prevention (LICP). METHODS: Twenty-one human non-carious molars were selected. The teeth were covered with nail varnish, except two 4 mm x 1 mm windows on both the buccal and lingual surfaces. The windows were randomly assigned to groups A, B, C and D, receiving no irradiation, 100, 200 and 300 mJ irradiation, respectively. The pulse width 10 pps (pulse per second) with a 1.0 mm spot size was used. After the laser treatment, each tooth was cut into two halves longitudinally. Then a two-day pH-cycling was performed, with an 18-hour demineralization followed by a 6-hour remineralization. Sections of 120 +/- 20 microm in thickness were obtained from each window. Lesion depth was measured using polarized light microscope coupled with an image analysis software. One-way ANOVA and post-hoc Tukey tests were used for evaluation of treatment effects. RESULTS: The laser treatments of 100 and 200 mJ have demonstrated significant protection of enamel demineralization (p = 0.01 and 0.001, respectively), but not the treatment with 300 mJ (p = 0.106). A smaller lesion depth was observed for the 200 mJ group (97.1 microm) than that of the 100 mJ group (105.6 microm). Compared with the control, a lesion reduction of 32.78 and 26.93% for the 200 mJ group and the 100 mJ group were obtained, respectively. CONCLUSION: Caries prevention may be achieved by using Er:YAG laser treatment if the optimal range of laser parameters for LICP can be employed.
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Esmalte Dentário/efeitos da radiação , Terapia a Laser , Desmineralização do Dente/prevenção & controle , Alumínio , Análise de Variância , Humanos , Desmineralização do Dente/radioterapia , ÍtrioRESUMO
OBJECTIVE: To evaluate the clinical efficiency and patient acceptance during cavity preparation in children, a direct comparison was made between Er:YAG laser preparation and conventional mechanical preparation of caries using a split-mouth design. BACKGROUND DATA: The Er:YAG laser system was developed for cutting dental hard tissue and has been approved as a useful alternative method for cavity preparation. METHODS: Children with previously unrestored and matched carious cavities in non-pulpally involved anterior teeth were selected, and the sequential order of treatment was randomized. In total, 40 children from 4 to 12 years old took part in the study. Two teeth each in the 40 patients were prepared without anesthesia and restored with a light-cured compomer following application of a bonding agent. The time spent on cavity preparation and the behavior of the patients during cavity preparation were recorded; finally, a modified face scale was used for pain assessment. In addition, the children were asked to indicate whether they found the laser or the mechanical approach more uncomfortable, and their preferred treatment when undergoing future caries therapy. RESULTS: The analysis of pain indicated that 82.5% of children felt no pain at all with the laser preparation, and they also showed much more body and head movement with the conventional mechanical preparation. Although the Er:YAG laser took about 2.35 times longer to prepare the same type of cavity, 92% of the children said that they would prefer laser preparation for further caries therapy. CONCLUSION: Cavity preparation with the Er:YAG laser would seem to be an option for fearful children, since it produces less pain and has acceptable efficiency compared to the conventional mechanical preparation.