Arch parameters and dental discrepancy (crowding and spacing) in a sample of an Afro-Colombian population / Parámetros de arco y discrepancia dental (apiñamiento y espaciamiento) en una muestra de población Afrocolombiana

The aim of this study was to determine the differences in arch length, inter-canine distance, inter-premolar distance, intermolar distance and arch shape between dental discrepancies (crowding and spacing) in a sample of dental casts from the Afro-Colombian population of San Basilio de Palenque. An analytical, cross-sectional study was conducted on a convenience sample of 63 subjects aged 11 to 57years, of Afro-Colombian origin, with full dentition from first molar to first molar, without extensive caries or restorations, and excluding casts with defects due to loss. The differences between arch (upper and lower) variables were analyzed according to dental discrepancies. Plaster models digitalized with a TR1OS3 Mono scanner with exactitude (6.9 ± 0.9 pm) and precision (4.5 ± 0.9 pm) were analyzed with Orthonalyzer software. Statistical analyses were done on SPSS software (Version 20 for Windows) and Real Statistics. Spacing discrepancy of68.25% was found for upper arch and 66.66% for lower arch; crowding discrepancy of 19.04% for upper arch and 20.63% for lower arch, and an adequate ratio of 12.69% for both arches. No statistically significant difference (p>0.05) was found between arch parameters except for inter-premolar distance on the lower arch. The most frequent arch shape in the population was oval for both upper arch, with 76.19%, and lower arch, with 71.42%. Tooth size was larger in males than females but the difference was not statistically significant.

El objetivo de este estudio fue determinar las diferencias en longitud de arco, distancia intercanina, interpremolar, intermolar y la forma de arco entre discrepancias dentales (apiñamiento y espaciamiento), en una muestra de modelos dentales de la población afrocolombiana de San Basilio de Palenque. Se realizó un estudio analítico transversal, en una muestra por conveniencia de 63 sujetos con un rango de edad entre 11 y 57 años, de origen afrocolombiano, quienes tuvieron dentición completa de primer molar a primer molar, sin caries extensas, ni restauraciones; se excluyeron los modelos con defectos por el vaciado. Se analizaron las diferencias entre las variables de los maxilares (superior e inferior) con las discrepancias dentales. Se utilizaron modelos de yeso que fueron digitalizados con el escánerTR1OS3 Mono con una exactitud de (6.9 ± 0.9 pm) y una precisión de (4.5 ± 0.9 pm)y analizados con el software Orthonalyzer. Los análisis estadísticos se llevaron a cabo utilizando el software SPSS (Versión 20 para Windows) y Real Statistics. Se encontró una discrepancia de espaciamiento de un 68,25% para el arco superior y 66,66% en el arco inferior; y una discrepancia de apiñamiento en el arco superior de 19,04% e inferior de 20,63% y una relación adecuada de 12,69% para los dos arcos. No se encontraron diferencias estadísticamente significativas (p>0.05) en los parámetros de arco a excepción de la distancia interpremolar del arco inferior. La forma de arco más frecuente en la población fue ovalada tanto en el arco superior con un 76,19% como en el arco inferior con un 71,42%. En cuanto al tamaño dental, se presentó mayor tamaño en los hombres que en las mujeres, pero este no fue estadísticamente significativo.

Pulp canal obliteration after traumatic injuries in permanent teeth - scientific fact or fiction?

Abstract: Pulp canal obliteration (PCO) is a frequent finding associated with pulpal revascularization after luxation injuries of young permanent teeth. The underlying mechanisms of PCO are still unclear, and no experimental scientific evidence is available, except the results of a single histopathological study. The lack of sound knowledge concerning this process gives rise to controversies, including the most suitable denomination. More than a mere semantic question, the denomination is an important issue, because it reflects the nature of this process, and directly impacts the treatment plan decision. The hypothesis that accelerated dentin deposition is related to the loss of neural control over odontoblastic secretory activity is well accepted, but demands further supportive studies. PCO is seen radiographically as a rapid narrowing of pulp canal space, whereas common clinical features are yellow crown discoloration and a lower or non-response to sensibility tests. Late development of pulp necrosis and periapical disease are rare complications after PCO, rendering prophylactic endodontic intervention useless. Indeed, yellowish or gray crown discoloration may pose a challenge to clinicians, and may demand endodontic intervention to help restore aesthetics. This literature review was conducted to discuss currently available information concerning PCO after traumatic dental injuries (TDI), and was gathered according to three topics: I) physiopathology of PCO after TDI; II) frequency and predictors of pulpal healing induced by PCO; and III) clinical findings related to PCO. Review articles, original studies and case reports were included aiming to support clinical decisions during the follow-up of teeth with PCO, and highlight future research strategies.

Efeito de diferentes sistemas de obturação na resistência à fratura de raízes tratadas endodonticamente / The Influence of different obturation systems on the fracture resistance of endodontically treated roots

Objective: This study aimed to compare the fracture resistance of endodontically treated roots filled by different obturation systems. Material and methods: Ninety-six maxillary central incisors were used and decoronated, retaining 12 mm of the roots. On the basis of obturation systems, the roots were randomly divided into 4 groups (n=24): Group1 (COGR): control group (unprepared, unfilled), Group 2 (AVGR): ActiV GP points/ActiV GP sealer, Group 3 (GPGR): Gutta percha points / AH plus sealer, and Group4 (GAGR): Gutta percha points/ActiV GP sealer. The last three groups were obturated with the single cone technique. The roots were then stored in 100% relative humidity at 37 °C for 2 weeks. A vertical compressive force was exerted in a universal testing machine until fracture occurred. Data were statistically analyzed using one-way ANOVA. Results: Mean (SD) failure loads for groups ranged from 920.51 ± 210.37 to 1113.44 ± 489.42 N. The fracture resistance between the different study groups indicated no statistical difference (p>0.05). Conclusions: ActiV GP system did not exert a significant effect on the fracture resistance of endodontically treated teeth.(AU)

Objective: Comparar a resistência à fratura de raízes tratadas endodonticamente obturadas através de diferentes sistemas. Materiais e Métodos: Noventa e seis incisivos centrais superiores foram utilizados, tiveram as coroas removidas, restando 12 mm de raíz. De acordo com o sistema de obturação, as raízes foram divididas em 4 grupos (n=24): Grupo1 (COGR): grupo controle (sem preparo, sem preenchimento), Grupo2 (AVGR): cones ActiV GP / cimento ActiV GP, Grupo3 (GPGR): cones de guta percha / cimento AH plus, e Grupo4 (GAGR): cones de guta percha / cimento ActiV GP. Os últimos três grupos foram obturados através da técnica de cone único. As raízes foram armazenadas em 100% de umidade relativa a 37 °C durante 2 semanas. Uma força compressiva vertical foi aplicada através de uma máquina de ensaio universal até ocorrer fratura. Os dados foram analisados estatisticamente através de ANOVA ­ 1 fator. Resultados: A carga média (SD) obtida no momento da falha variou entre 920.51 ± 210.37 até 1113.44 ± 489.42 N. A resistência à fratura entre os diferentes grupos estudados não indicaram diferença estatística. Conclusão: O sistema ActiV GP não exerceu um efeito significante na resistência à fratura em dentes tratados endodonticamente.(AU)

Evaluation of the vertical alterations of the upper second molars after the alignment and leveling phase using the MBT technique

OBJECTIVE: This study aimed at comparing the distocervical angulations of upper second molars crowns of groups with normal occlusion and with Angle Class I and II malocclusions. Additionally, it aimed to analyze the changes occurring after alignment and leveling performed with MBT technique. METHODS: The sample of normal occlusions comprised 32 lateral teleradiographs, while the sample of malocclusions comprised 38 initial and post-leveling lateral teleradiographs. RESULTS: The results did not show statistically significant differences between morphological characteristics of the normal occlusion group and the malocclusion group. On the other hand, after alignment and leveling, statistically significant reduction was observed in distocervical inclinations with extrusion of the distal portion of upper second molars.

OBJETIVO: a proposta do presente trabalho foi comparar as angulações distocervicais das coroas dos segundos molares superiores de um grupo com oclusão normal e outro composto de más oclusões de Classes I e II de Angle, e analisar as modificações ocorridas após o alinhamento e nivelamento com a técnica MBT. MÉTODOS: a amostra de oclusão normal foi composta por 32 telerradiografias laterais; e a amostra de má oclusão constituiu-se de 38 telerradiografias laterais iniciais e pós-nivelamento. RESULTADOS: os resultados não mostraram diferença estatisticamente significativa entre as características morfológicas dos grupos com oclusão normal e com má oclusão; porém, após o alinhamento e nivelamento, observamos redução estatisticamente significativa nas inclinações distocervicais, com extrusão da porção distal dos segundos molares superiores.

Applicability of Tanaka and Johnston mixed dentition analysis in a contemproary Pakistani population

Mixed dentition analysis is carried out to predict the size of unerupted canine and premolar in the developing occlusion. The aim of this study was to assess the applicability of Tanaka and Johnston method of mixed dentition analysis in predicting the size of permanent canines and premolars in patients visiting Islamic International Dental Hospital, Islamabad. The sample consisted of 80 dental casts [40 male and 40 female], obtained from patients reporting at the department of orthodontics, Islamic International Dental College, Islamabad with the age range between 12 to 21 years. Mesiodistal tooth widths were measured with a digital vernier caliper. A paired student t test was used to compare the predicted and actual sum of the maxillary [PUCPM and AUCPM] and mandibular permanent Canines and Premolars [PLCM and ALCPM] for both genders combined and separately. Significant difference was found between PUCPM and AUCPM in maxilla for both male and female together [M + F: 0.000] and when both genders were compared separately [M: 0.032, F: 0.001]. Tanaka and Johnston method was only applicable in predicting the space for unerupted canine and premolars in mandible in both male and female sample

Effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors

The purpose of this study was to compare the effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors during leveling phase. Twenty-three subjects with Class I and Class II malocclusion were treated with first premolars extraction using preadjusted appliances (MBT 0.022-inch brackets). The leveling phase was performed with stainless steel archwires only. The sample was divided into 2 groups: 14 subjects received active lacebacks (Group 1) and 9 subjects received passive lacebacks (Group 2). Lacebacks were made from 0.008-inch ligature wire. Lateral cephalometric radiographs were taken pre- and post-leveling phase. Student's t-test was applied to determine the differences between pre- and post-leveling mean values and to determine the mean differences between groups. In Group I, the first molars showed a significant mesial movement, whereas no change was observed in Group 2. In both groups, maxillary central incisor crowns moved to lingual side. In conclusion, active laceback produced anchorage loss of maxillary first molars whereas passive laceback did not affect the position of these teeth. Active and passive lacebacks were effective in preventing central incisor proclination.

O objetivo deste estudo foi comparar os efeitos dos lacebacks ativos e passivos na posição ântero-posterior dos primeiros molares e dos incisivos centrais superiores durante a fase de nivelamento. Vinte e três indivíduos com má oclusão de Classes I e II foram tratados com extrações dos primeiros pré-molares utilizando aparelhos fixos pré-ajustados (bráquetes MBT 0,022"). A fase de nivelamento foi realizada somente com arcos de aço inoxidável. A amostra foi dividida em 2 grupos: 14 pacientes receberam lacebacks ativos (Grupo 1) e 9 pacientes receberam lacebacks passivos (Grupo 2). Os lacebacks foram feitos com fio de ligadura de 0,008" (0,20 mm). Telerradiografias laterais foram realizadas antes e após a fase de nivelamento. O teste t de Student foi aplicado para determinar as diferenças entre as médias de deslocamento entre os períodos pré e pós-nivelamento e para determinar as diferenças entre os grupos. No Grupo 1, o primeiro molar mostrou uma movimentação mesial significativa enquanto nenhuma alteração foi observada no Grupo 2. Em ambos os grupos, os incisivos centrais superiores foram lingualizados. Em conclusão, os lacebacks ativos produziram perda de ancoragem nos primeiros molares superiores enquanto que os lacebacks passivos não afetaram a posição destes dentes. Lacebacks ativos e passivos foram efetivos para prevenir a vestibularização dos incisivos centrais superiores.

Pericoronaritis aguda en adolescentes y adultos jóvenes de un consultorio estomatológico del municipio venezolano de Valencia / Acute pericoronitis in adolescents and young adults in a dentist's office from the Venezuelan municipality of Valencia

Se realizó una investigación prospectiva longitudinal para describir la pericoronaritis en 150 pacientes de 15 a 26 años, seleccionados de forma intencional de 200 que asistieron al consultorio Adaca, del área de salud integral comunitaria Socorro del municipio venezolano de Valencia, estado de Carabobo, desde septiembre de 2009 hasta febrero 2010. La casuística fue distribuida en: grupo I, constituido por 75 individuos con diagnóstico de dientes retenidos o semirretenidos; y grupo II, conformado por igual número, pero sin esa condición en las piezas dentarias. Para relacionar las variables entre sí se utilizó la distribución probabilística de Ji al cuadrado, con un nivel de asociación de a=0,05; y para determinar el riesgo estimado se empleó la razón de productos cruzados, además de calcularse los intervalos de confianza al 95 por ciento . En la serie predominaron los pacientes de 15-20 años y del sexo masculino; la pericoronaritis se halló en 24,0 por ciento del total, con una asociación de riesgo más elevada en el grupo I, en la mayoría de cuyos integrantes se observaron ambas formas agudas de la inflamación: congestiva o serosa y supurada. El tercer molar fue el más afectado en ambos grupos.

A longitudinal prospective study was carried out to describe pericoronitis in 150 patients from 15 to 26 years, intentionally selected from over 200 who attended Adaca dentist's office from Socorro community comprehensive health area in the Venezuelan municipality of Valencia, Carabobo State, from September 2009 to February 2010. Our cases were distributed into group I consisting of 75 individuals with diagnosis of retained or semi-retained teeth, and group II with the same number of people but without that condition in the teeth. To relate the variables each chi-square probability distribution was used with a level of association=0,05, and to determine the estimated risk odds ratio was used and 95 percent confidence intervals were calculated. Male patients of 15-20 years prevailed in the series, and pericoronitis was found in 24,0 percent of the total with a higher risk association in the group I, in most of whom both acute forms of congestive or serous and suppurative inflammation were observed. The third molar was the most affected in both groups.

Restoration of posterior teeth using occlusal matrix technique.

This article describes a technique for duplicating occlusal surface anatomy using the Biteperf device. Duplication requires an intact occlusal enamel surface and is only indicated when caries lesions are hidden. The occlusal matrix technique allows for preservation of all anatomic details. When the last layer of composite has been placed, the occlusal matrix is forced into the uncured composite to replicate the original occlusal surface, instead of performing manual curing and shaping as in the standard approach. It is technically possible to achieve this effect with any material that is able to copy anatomic details. The main benefits of the occlusal matrix technique, more precisely the Biteperf, are the technical ease of use due to its simplicity and its high accuracy in reconstructing occlusal morphology.

Microbiological and microscopic analysis of the pulp of non-vital traumatized teeth with intact crowns

OBJECTIVE: This study evaluated the presence of microorganisms and analyzed microscopically the pulp of 20 traumatized human teeth with intact crowns and clinical diagnosis of pulp necrosis, based on the association of at least three of the clinical criteria: crown discoloration, negative response to thermal and electric pulp vitality tests, positive response to vertical and horizontal percussion, pain on palpation or mobility. MATERIAL AND METHODS: Microbiological collection was performed from the root canals to evaluate the presence of microorganisms. The pulp samples were stained with hematoxylin and eosin (H.E.) for histological evaluation of possible morphological alterations. RESULTS: Analysis of results was performed by statistical tests (linear regression test and diagnostic analysis) and subjective analysis of the sections stained with H.E. and revealed that only 15 percent of the sample did not exhibit microbial development. The time elapsed between dental trauma and onset of endodontic intervention ranged from 15 days to 31 months; the percussion test presented high sensitivity (80 percent) for detection of microorganisms in the root canal of traumatized teeth; 3 teeth (15 percent) did not present pulp tissue, being characterized as complete autolysis; analysis of pulp samples was performed on the other 17 cases, among which 3 (15 percent) exhibited partial necrosis without possibility of repair and 14 presented complete necrosis; none of the clinical criteria employed for the diagnosis of pulp necrosis in traumatized teeth was pathognomonic. CONCLUSIONS: The present results allowed the following conclusions: with regard to microbiological findings, 85 percent of teeth presented microorganisms in the root canal, despite the presence of an intact crown. Concerning the microscopic findings, 100 percent of traumatized teeth presented pulp necrosis; the pulp vitality tests based on pulp response to heat, cold and vertical percussion ...

Multiple dental anomalies and aggressive periodontitis: A coincidence or an association.

Aggressive periodontitis (AgP) comprises a group of rare, often severe, rapidly progressive forms of periodontitis mostly characterized by an early age of clinical manifestation and a distinctive tendency for cases to aggregate in families. Abnormal dental morphology and position have been associated with severe periodontal diseases. The purpose of this paper is to report a case of multiple dental anomalies associated with AgP. This paper reports a case of unusual association of multiple dental anomalies to AgP. Clinical findings and history led to the diagnosis of localized AgP, and radiologically. It was associated with multiple dental anomalies, especially supernumerary roots. Thus, the present case represents a very interesting demonstration of AgP association with supernumerary roots and the nature of this association merits further investigations.

The relative diagnostic yields of clinical, FOTI and radiographic examinations for the detection of approximal caries in youngsters.

Background: The detection of carious lesions in the initial stages of development is very important in order to prevent the occurrence of cavitation. Aims and Objectives: The aim of the present study was to compare three methods-visual examination, FOTI, and bitewing radiographic examination-for the detection of noncavitated and cavitated approximal carious lesions. Materials and Methods: Seventy students (mean age 14 years) with low caries prevalence were examined by three examiners. The tooth surfaces judged as having caries by at least one examiner or one diagnostic method were scheduled for tooth separation. Results: The results showed that the incorporation of FOTI and radiographic examination represented an additional diagnostic yield of 50% and about 110%, respectively, compared to clinical examination alone. Conclusion: We conclude that FOTI or radiographic examination, or both, used as adjuncts to clinical examination, could improve the detection of noncavitated and cavitated approximal carious lesions. Although FOTI should not replace bitewing radiographic examination, it does seem to have additional value for the detection of carious lesions on approximal surfaces of the posterior teeth in school children with low caries prevalence.

Influence of intraradicular post and crown ferrule on the fracture strength of endodontically treated teeth

The aim of this study was to investigate the fracture strength of endodontically treated teeth restored with different posts and variable ferrule heights. Sixty freshly extracted human canines were treated endodontically and randomly assigned to 6 groups (n=10), being restored with custom-made cast post-and-core (CP0 and CP3 groups), prefabricated post and composite resin core (PF0 and PF3 groups), and composite resin (CR0 and CR3 groups). The CP0, PF0 and CR0 groups presented no ferrule and the CP3, PF3 and CR3 presented 3 mm of coronal structure. All teeth were restored with full metal crowns. The fracture strength was measured in a universal testing machine at 45o to the long axis of the tooth until failure. Data were analyzed statistically by 2-way ANOVA and Tukey's test (?=0.05). When the mean fracture strength values were compared (CP0 group - 820.20 N, CP3 group - 1179.12 N; PF0 group - 561.05 N; PF3 group - 906.79 N; CR0 group - 297.84 N; and CR3 group - 1135.15 N) there was statistically significant among the groups (p<0.05), except for the three groups with 3 mm of coronal remaining, which were similar to each other. The results of this study showed that the ferrule in crowns promoted significantly higher fracture strength in the endodontically treated teeth.

O objetivo neste estudo foi avaliar a resistência à fratura de dentes tratados endodonticamente restaurados com diferentes pinos e diferentes alturas de remanescente dentinário da coroa. Sessenta caninos recém-extraídos foram tratados endodonticamente, separados em 6 grupos (n=10) e restaurados com núcleo metálico fundido (CP0 e CP3), pino pré-fabricado e núcleo em resina composta (PF0 e PF3) ou resina composta (CR0 e CR3). Os grupos CP0, PF0 e CR0 não possuíam férula e os grupos CP3, PF3 e CR3 apresentaram 3 mm de remanescente coronário. Todos os dentes foram restaurados com coroas totais metálicas. A resistência à fratura foi medida em máquina universal de ensaios com o longo eixo do dente posicionado a 45 graus em relação ao carregamento axial, até que ocorresse fratura. A análise de variância 2 critérios (?=0,05) mostrou diferença estatisticamente significativa entre os grupos. Quando as médias das forças para fratura foram comparadas (CP0 = 820,0 N; CP3= 1179,12 N; PF0 = 561,05 N; PF3 = 906,79 N; CR0 = 297,84 N; e CR3 = 1135,15 N) não foram observadas diferenças significativas entre os 3 grupos com 3 mm de remanescente coronal. Os resultados mostraram que a presença de férula em coroas aumenta significantemente a resistência à fratura de dentes tratados endodonticamente.

A comparative study of the efficacy of four different bristle designs of tooth brushes in plaque removal.

BACKGROUND: The aim of the study was to compare the efficacy of four most commonly used bristle designs of toothbrushes in plaque removal. MATERIALS AND METHODS: The study was a randomized 4 cell, examiner blind cross-over design assessing the plaque removal efficacy of all four brushes on a single occasion. Sixteen subjects aged 14-15 years participated in the study. On day 1 of each test period, the subjects were rendered plaque free and were asked to suspend oral hygiene practices for 24 hours. On day 2, the subjects were scored for plaque prior to brushing using the Turesky-Gilmore modification of Quigley-Hein plaque index. The subjects then brushed with the allocated toothbrush for 2 minutes and the post-brushing plaque scores were assessed. A wash-out period of 4 days was allowed between the test periods. RESULTS : All the brushes showed a significant reduction in the post-brushing plaque scores ( p < 0.001). The mean reduction in the plaque scores for all the brushes was around 53%. The percentage plaque reduction was greater in the anterior surface than the posterior surface (59.6 +/- 7.45% vs. 49.83 +/- 4.35%). The percentage plaque reductions in the upper, lower, buccal and lingual surfaces were similar. No significant difference in the reduction of plaque scores between the four brushes was seen. CONCLUSION: The data derived from the study supports the contention of many researchers that there is no single superior design of manual toothbrush. Though minor and some site differences in favor of the brushes were seen, they were not statistically significant.

Tooth structure and fracture strength of cavities

This study evaluated, in vitro, the loss of tooth substance after cavity preparation for direct and indirect restorations and its relationship with fracture strength of the prepared teeth. Sixty sound human maxillary first premolars were assigned to 6 groups (n=10). MOD direct composite cavities (Groups I, II and III) and indirect inlay cavities (Groups IV, V and VI) were prepared maintaining standardized dimensions: 2-mm deep pulpal floors, 1.5-mm wide gingival walls and 2-mm high axial walls. Buccolingual width of the occlusal box was established at 1/4 (Groups I and IV), 1/3 (Groups II and V) or 1/2 (Groups III and VI) of the intercuspal distance. Teeth were weighed (digital balance accurate to 0.001 g) before and after preparation to record tooth substance mass lost during cavity preparation. The prepared teeth were submitted to occlusal loading to determine their fracture strength using a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed by two-way ANOVA and Tukey test (alpha= 0.05). 1/4-inlay cavities had higher percent mean mass loss (9.71 percent) than composite resin cavities with the same width (7.07 percent). 1/3-inlay preparations also produced higher percent mean mass loss (13.91 percent) than composite resin preparations with the same width (10.02 percent). 1/2-inlay cavities had 21.34 percent of mass loss versus 16.19 percent for the 1/2-composite resin cavities. Fracture strength means (in kgf) were: GI = 187.65; GII = 143.62; GIII = 74.10; GIV = 164.22; GV = 101.92; GVI = 50.35. Statistically significant difference (p<0.05) were observed between Groups I and IV, II and V, III and VI. Higher tooth structure loss and lower fracture strength were recorded after preparation of inlay cavities, regardless of the width of the occlusal box, compared to the direct composite resin cavities.

O objetivo deste estudo foi avaliar, in vitro, a perda de estrutura dentária após o preparo cavitário para restaurações diretas e indiretas e sua relação com a resistência à fratura do dente. 60 pré-molares superiores humanos foram divididos em 6 grupos (n=10). Cavidades MOD para resina composta direta (Grupos I, II e III) e cavidades "inlay" (Grupos IV, V e VI) foram preparadas mantendo dimensões padronizadas. A extensão vestíbulo-lingual da caixa oclusal foi estabelecida em 1/4 (Grupos I e IV), 1/3 (Grupos II e V) ou 1/2 (Grupos III e VI) da distância intercuspídea. Os dentes foram pesados, em uma balança de precisão, antes e após o preparo cavitário para aferir a perda de massa dentária. Os dentes preparados foram submetidos à força de compressão para determinar a resistência à fratura em uma máquina universal de ensaios sob uma velocidade de 0.5 mm/min. Os dados foram submetidos à análise de variância a dois critérios e ao teste de Tukey (alfa = 0.05). As cavidades do tipo "1/4-inlay" apresentaram maior percentual de perda de massa (9.71 por cento) em relação às cavidades para resina composta com mesma extensão (7.07 por cento). As cavidades do tipo "1/3-inlay" também apresentaram maior percentual de perda de massa (13.91 por cento) quando comparada às cavidades para resina composta com a mesma extensão (10.02 por cento). As cavidades do tipo "1/2-inlay" apresentaram 21.34 por cento de perda de massa, enquanto as cavidades com extensão de 1/2 para resina composta apresentaram uma perda de 16.19 por cento. As médias de resistência à fratura (em kgf) foram: GI = 187.65; GII = 143.62; GIII = 74.10; GIV = 164.22; GV = 101.92; GVI = 50.35. Diferenças estatisticamente significantes (p<0.5) foram observadas entre os Grupos I e IV, II e V, III e VI. Maior perda de estrutura dentária e menor resistência à fratura foram verificadas após os preparos do tipo "inlay" quando comparados aos preparos para resina composta direta.

Effects of elevated temperatures on various restorative materials: an in vitro study.

In cases of mass disasters associated with fire, identification of the burnt victims can be a real challenge to the forensic team. Teeth and their restorations play a significant role to aid in the identification process, as various restorative materials have varying resistance to high temperatures. A study was undertaken to evaluate the changes taking place on teeth restored with amalgam, composites, glass ionomers, heat cure acrylic, and ceramics. The specimens were placed in a furnace and heated to predetermined temperatures of 200, 400, 600, 800, and 1000 degrees C and the changes were examined using a digital camera and stereomicroscope. Our observations show that while some restorations were able to withstand elevated temperatures, others were reduced to an unrecognizable mass at relatively low temperatures.

Biologic restoration of primary anterior teeth: a case report.

Restoration of primary maxillary incisors, severely destroyed by trauma or caries is a commonly faced problem in a Pediatric dental clinic. Most cases are observed in children with early childhood caries. In the past, the only option would have been to extract the affected teeth and replace them with prosthetic substitutes. However, the availability of natural crowns and roots would allow the use of biologic restorations to preserve the integrity of patient's natural dentition as presented in this case report.

Natal and neonatal teeth: a case report.

A case of natal and neonatal teeth in a 25 days old infant and its management is reported.

Reconstruçäo das paredes perdidas do dente com resina composta fotopolimerizável em isolamento absoluto / Rebuilding the entire crown partially destroyed of teeth with activated resin in absolute isolation

A finalidade do presente trabalho é mostrar uma técnica simples e fácil de reconstruir a coroa total ou parcialmente destruída de dentes que iräo receber tratamento endodôntico. A colocaçäo do isolamento absoluto é um passo fundamental para o sucesso do tratamento endodôntico. O dique de borracha proporciona o afastamento dos tecidos moles da boca, levando a uma melhor visäo do campo operatório; protege o paciente e o profissional e principalmente, impede a penetraçäo de saliva, mantendo meio asséptico para o tratamento do sistema de canais radiculares. O material escolhido para a reconstruçäo provisória das paredes perdidas dos dentes foi a resina composta fotopolimerizável, precedida do condicionamento das estruturas dentárias remanescentes com ácido fosfórico a 37 por cento, aplicaçäo do primer e do agente de uniäo. A reconstruçäo permite a colocaçäo do grampo para isolamento absoluto, sem deslocar a restauraçäo provisória. Se o tratamento endodôntico for realizado em mais de uma sessäo, a restauraçäo provisória permanece no lugar, favorecendo o próximo isolamento absoluto, além de estabilizar o curativo de demora, mantendo as condiçöes assépticas até aqui conseguidas

Radiolucência intracoronária em molares permanentes näo-erupcionados: relato de dois casos / Intracoronal radiolucencies in unerupted permanent molars: report of two cases

Reabsorçäo intracoronária pré-eruptiva é uma condiçäo rara, de etiologia idiopática e comumente diagnosticada no exame radiográfico rotineiro ou com fins ortodônticos. O tratamento proposto é o acompanhamento radiográfico até que o elemento erupcione para que entäo seja feita a intervençäo. Entretanto, na presença de sintomatologia dolorosa ou progressäo da lesäo, recomenda-se a exposiçäo cirúrgica do elemento afetado, colocaçäo de hidróxido de cálcio e curativo de óxido de zinco e eugenol para posterior restauraçäo. O objetivo deste trabalho é relatar dois casos sobre reabsorçäo intracornária em molares permanentes

Restaurações indiretas: técnica alternativa na reabilitação bucal em odontopediatria / Indirect restorative technique: an alternative in oral rehabilitation in pediatric dentistry

Este artigo tem por finalidade principal, oferecer uma contribuição ao clínico-geral e ao odontopediatra para a restauração de molares decíduos com grande destruição coronária