4 research outputs found
Restauração directa de classes II em pré-molares com compósitos: estudos comparativos, in vivo e in vitro, de duas técnicas restauradoras
Tese de Doutoramento apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Doutor em em Biotecnologia e Saúde,
Epidemiologia e Saúde Pública.A restauração de dentes posteriores deve basear-se na evidência científica. A
investigação in vitro indica as probabilidades de excelência duma técnica ou possibilita
a certificação dos materiais para uso clínico. As restaurações devem ser avaliadas, in
vivo, pelo menos durante 2 anos previamente à comercialização dos materiais
restauradores. Este trabalho de investigação avaliou e comparou, clínica
(comportamento clínico) e laboratorialmente (microinfiltração), a eficácia de duas
técnicas de restauração (incremental oblíqua (TIO) e incremental modificada (TIM)) e
de dois tipos de compósitos, de alta (microhíbrido, condensável) e de média
viscosidades (nanohíbrido), em restaurações de classes II (ocluso-mesial e/ou oclusodistal)
em dentes pré-molares. Conforme a técnica/viscosidade da resina composta
constituíram-se três grupos, o A (TIO com nanohíbrido), o B (TIM com nanohíbrido e
condensável) e o C (TIO com condensável). A amostra in vivo contou com 105
restaurações. No ensaio in vitro foram efectuados 4 microcortes no sentido mésio-distal
de 30 pré-molares com restaurações mésio e disto-oclusais, obtendo-se uma amostra de
720 superfícies. A avaliação in vivo foi efectuada semestralmente, até aos 24 meses, por
inspecção clínica directa e indirecta de fotografias (critérios de Ryge modificados),
radiografias e modelos (Hickel et al. 2007). No ensaio in vitro a microinfiltração foi
quantificada pelo índice e nível de infiltração, e analisada a influência da
presença/ausência e espessura de esmalte. In vivo, todos os grupos evidenciaram um
bom comportamento estético, funcional e biológico das restaurações. Aos 12 meses, a
eficácia foi maior no grupo A (A>C>B; p>0,05). A TIM e a TIO mostraram taxas de
sucesso estético e funcional máximos mas, apresentaram fracasso de causa biológica
num parâmetro (p>0,05). Aos 24 meses, o grupo C foi mais eficaz (C>A>B; p<0,05). A
TIM mostrou menor taxa de sucesso geral que a TIO (Estético: TIMTIO, p>0,05; Biológico: TIM0,05). No ensaio in vitro, o
grupo B foi o mais eficaz (B>C>A; p<0,05) por registo de menor frequência e
gravidade de infiltração. A TIM foi mais eficaz que a TIO (p<0,05).
Posterior teeth restoration must be based on scientific evidence. In vitro studies point
out the probability of excellence of a technique or the accomplishment of the
certification of materials for clinical use. The restorations must be evaluated, in vivo, at
least during 2 years previously to the commercialisation of the restoring materials. This
research evaluated and compared, in vivo (clinical performance) and in vitro
(microleakage), the effectiveness of two restoration techniques (oblique incremental
(OIT) and modified incremental (MIT)) and two types of resin based composites, a high
(microhybrid, packable) and an average (nanohybrid) viscosities of class II (occlusalmesial
and/or occlusal-distal) restorations in premolar teeth. Three groups were
constituted according to the technique/composite viscosities, A (nanohybrid with OIT),
B (nanohyrid and packable with MIT) and C (packable with OIT) groups. The in vivo
sample size comprised 105 restorations. For the in vitro study 30 premolar teeth, with
mesial and distal-occlusal restorations, were longitudinally sectioned with a diamond
saw: 4 sections per tooth provided 720 surfaces for evaluation. The in vivo evaluation
was done each six month up to 24 months, by direct clinical inspection and indirectly
using photographs (Ryge modified criteria), x-rays and casts (Hickel et al. 2007). In the
in vitro study microleakage was quantified by means of a leakage index and levels of
leakage and the analysis of the influence of the presence/absence of enamel and of its
thickness. In vivo, all restorations groups showed good aesthetic, functional and
biological behaviour. At 12 months the effectiveness was higher in the A group
(A>C>B; p>0.05). The MIT and the OIT showed maximum clinical aesthetic and
functional success but presented biological failure in one parameter (p>0.05). At 24
months C group was the most efficient (C>A>B; p<0.05). The MIT showed lower
general success than the OIT (Aesthetic: TIMTIO,p>0.05; Biological: TIM0.05). In the in vitro study, B group was the most
efficient (B>C>A; p<0.05) as it showed lower microleakeage frequency and severity
degree. The MIT was more efficient than the OIT (p<0.05).
La restauration de dents postérieures doit être basée sur la preuve scientifique. Les
études in vitro indiquent la probabilité d'une technique d’excellence ou possibilitent la
certification de matériaux pour l'usage clinique. Les restaurations doivent être évaluées,
in vivo, au moins pendant 2 ans avant la commercialisation des matériaux de
restauration. Cette recherche a évalué et comparé, in vivo (exécution clinique) et in vitro
(microinfiltration), l'efficacité de deux techniques de restauration (accroissement
oblique (TAO) et accroissement modifié (TAM)) et de deux types de composés a base
de résine, a haute (microhybride, condensable) et moyenne viscosité (nanohybride) en
restaurations (occlusif-mesial et/ou occlusif-distales) de la classe II en dents
prémolaires. Selon la technique et la viscosité des composés, trois groupes ont été
constitués, A (nanohybride avec TAO), B (nanohyride et condensable avec le TAM) et
C (condensable avec TAO). L'échantillon in vivo était composé par 105 restaurations.
Pour 'étude in vitro, 30 dents prémolaires, avec des restaurations mesial et distalocclusives,
ont été longitudinalement sectionnées avec une scie de diamant: 4 sections
par dent ont fourni 720 surfaces pour l'évaluation. L'évaluation in vivo a été faite chaque
six mois, jusqu'aux 24 mois, par inspection clinique directe et indirectement de
photographies (critères modifiés par Ryge), de radiographies et de moules (Hickel et
autres, 2007). Dans l'étude in vitro, le micro infiltration a été mesuré par l'index et le
niveau de fuite et par l’influence de la présence/absence et de l'épaisseur d'émail. Tous
les groupes ont démontré un bon comportement esthétique, fonctionnel et biologique
des restaurations. Après 12 mois, l'efficacité a été supérieure dans le groupe A (A>C>B;
p>0.05). La TAM et la TAO ont eu un succès esthétique et fonctionnel élevé et un
échec biologique (p>0.05). Après 24 mois, le groupe C a été le plus efficace (C>A>B;
pTAO, p>0.05 ; Biologique: TAM<TAO;
p>0.05). À l'étude in vitro, le groupe B a été le plus efficace (B>C>A; p<0.05)
démontrant une fréquence et sévérité de micro infiltration inférieures. La TAM a été
plus efficace que la TAO (p<0.05)
Fracture Resistance of Fiber-Reinforced Composite Restorations: A Systematic Review and Meta-Analysis
Composite resin is universally used for posterior teeth restorations. Fibers have been suggested for the mechanical improvement of the restorations. This study assessed the fracture resistance of class II fiber-reinforced composite restorations and compared it with the fracture resistance of three control groups: (1) healthy teeth, (2) non-fiber-reinforced restorations and (3) unrestored cavities. A search was performed using PubMed, Web of Science and Google Scholar from 15 May to 12 June 2023. Only in vitro studies from the last 10 years were included for this systematic analysis. This study was registered in the PROSPERO database, it followed PRISMA guidelines and the risk of bias was assessed using the QUIN tool. Fracture resistance median values, in Newtons (N), were calculated for the experimental and control groups (95% confidence interval). For pairwise comparison, nonparametric tests (p p p = 0.048) but higher values than non-fiber-reinforced restorations (771.0 N; p = 0.008) and unrestored cavities (386.6 N; p < 0.001). In vitro systematic outcomes evidenced that glass and/or polyethylene fibers improved the fracture resistance of composite restorations