Effect of using the New Glass Fiber Pin in Resin Composite Restorations.

AIM: The purpose was to compare the fracture strength between restorations containing the metal pin (MP) and those containing the glass fiber pin (GFP). MATERIALS AND METHODS: Forty-five healthy bovine anterior teeth were used in this study. A preparation of 4 mm × 4 mm was created on the incisal surface of each tooth. All teeth were prepared in the same way. The teeth were randomly divided into three groups (n = 15): group I-control: teeth restored with resin composite (RC) only, without reinforcement; group II-Each tooth was restored with a MP and RC; group III-Each tooth was restored with a GFP and RC. The specimens were left in an oven at a temperature of 37°C for 24 hours before performing the fracture strength tests. The fracture strength test was performed in a universal test machine at an angle of 90°. RESULTS: The Tukey test (p ≤ 0.05) showed that for the variable maximum force (kgf), there was no statistically significant difference among the groups (p = 0.272). The chi-square test showed that groups II and III presented over 70% of cohesive-adhesive type fractures when compared with group I (over 70% of adhesive fractures), and this difference was statistically significant (p < 0.05). CONCLUSION: The pins tested did not increase the fracture resistance of the restorations (RC) in comparison with group I (without reinforcement); however, with the use of the MP and GFP, there was a predominance of cohesive-adhesive fractures (groups II and III). CLINICAL SIGNIFICANCE: Evaluate if the new GFP can generate greater resistance to fracture of RC restorations.

Use of Pindex system in fabrication of the sectional custom tray.

This article describes a new, precise, and simple method for making an impression with an individual tray for a patient with microstomia. In this method, a Pindex system on the handle of the tray was used for attaching two parts of the sectional tray.

Shear resistance of fiber-reinforced composite and metal dentin pins.

PURPOSE: To assess whether dentin pins increase shear resistance of extensive composite restorations and to compare performance of mini fiber-reinforced composite (FRC) anchors with metal dentin pins in the laboratory. METHODS: 30 extracted sound molars were randomly divided into three groups. Occlusal surfaces were ground flat with a standard surface area and resin composite restorations were made in Group A. In Groups B and C similar restorations were made, with additionally four metal pins placed in Group B and four FRC pins in Group C. Specimens were statically loaded until failure occurred. Failure modes were characterized as intact remaining tooth substrate (adhesive or cohesive failure of restoration) or fractured remaining tooth substrate. RESULTS: Mean failure stresses were 6.5 MPa (SD 3.2 MPa) for Group A, 9.7 MPa (SD 2.6 MPa) for Group B and 9.2 MPa (SD 2.6 MPa) for Group C. Difference in mean failure stresses between Group A and Groups B and C was statistically significant (P = 0.01), while the difference between Groups B and C was not (P = 0.63). Failures of the restoration without fracture of tooth substrate were seen for 80% of specimens in Group A and 20% in Groups B and C (P = 0.04).

Are dentine pins obsolete?

Dentine pins have been used in operative dentistry for many years to retain a non-adhesive restorative material (such as dental amalgam) in a cavity which has little or no inherent mechanical retention. However, dentine pin placement can be a hazardous procedure and there are a number of problems associated with their use. Alternative techniques have been described which may be utilized and are effective at retaining the restorative material without the shortcomings of dentine pins. There is a strong argument therefore that dentine pins have no place in contemporary dental practice and have consequently become obsolete.

[Clinical experience based guidelines for one-step dental implantation].

The paper presents guidelines for one-step immediate implantation with simultaneous loading by means of provisional crown and subsequent ceramic restoration placement.

The long-forgotten technique of pin retained restoration - A case report.

To restore severely damaged teeth to the greatest state for health, function, and aesthetics continues to be a challenge for all practising dental surgeons. A pin retained restoration is an intricate restoration involving the insertion of one or more pins into the dentin to provide sufficient resistance and retention. These pins help in anchoring dental amalgam or composite to the tooth structure. This auxiliary retentive means help in the restoration of mutilated teeth in young individuals whose pulp chambers are relatively large and the dentinal tubules are comparatively immature. This case study sheds insights on the successful rehabilitation of a severely damaged premolar tooth with pins and composite resin restoration.

Resistance of composite and amalgam core foundations retained with and without pins and bonding agents.

To compare the resistance of different amalgam and composite core foundations retained by pins, bonding agents, or both, 100 molars were mounted in acrylic resin and their occlusal surfaces were reduced to expose dentin. Pins were inserted at the four line angles of the teeth and matrices were placed. Bonding agents were applied according to the manufacturers' instructions. Amalgam was handcondensed and composite was incrementally added and photocured. Restorations were adjusted to produce specimens (n = 10) 5 mm in height with a 1 mm bevel at the axial-occlusal surface. After immersion in deionized water for 24 hours, specimens were loaded at a 45 degree angle on their beveled surfaces in a Universal Testing Machine at a crosshead speed of 0.02 in./minute. ANOVA and Tukey's tests indicated that FluoroCore 2 (with or without pins) was statistically stronger than all other combinations (p < 0.05).

Conservative and esthetic cast gold fixed partial dentures-inlay, onlay, and partial veneer retainers, custom composite pontics, and stress breakers: part II: utilization of additional retentive features and fabrication of custom pontic facings.

Although in today's dental world implant restorations are considered the standard of care in the replacement of missing teeth, clinical contraindications and patient nonacceptance of implant placement can be encountered. Several scenarios are discussed here in which a single missing tooth can be restored with conservative fixed partial dentures (FPD) that employ cast gold retainers; each with a customized design in order to preserve tooth structure, maintain esthetics, and provide a long-term prognosis. The abutment teeth are prepared for conservative partial coverage restorations by using Brasseler burs (Brasseler USA, Savannah, GA, USA). Impressions are taken of the preparations, along with any retentive features, utilizing either the Vented Pin Channel technique or the Shooshan Plastic Pin technique. The latter technique utilizes Kodex twist drills and corresponding impression pins (Coltene Whaledent Inc., Mahwah, NJ, USA). The conservative FPD with non-rigid connectors is fabricated by using type III gold alloy. The pontic cage portion is chemically prepared utilizing the Panavia F2.0 cement kit (Kuraray America Inc., Houston, TX, USA) or other dual-polymerizing resin cement and restored with any type of direct composite resin material. A palette of opaquers and tints are used for chairside characterization of the esthetic pontic facing. The final polish of the pontic is completed by using FlexiDisc and FlexiBuff discs (Cosmedent Inc., Chicago, IL, USA). CLINICAL SIGNIFICANCE In cases where an implant restoration is contraindicated for replacement of a single tooth, a semi-precision FPD is a conservative, functional, and esthetic alternative.

Clinical longevity of metallic versus fiberglass intraradicular posts: a systematic review / Longevidade clínica de pinos intraradiculares metálicos versus de fibra de vidro: uma revisão sistemática

Objective: This systematic review aims to compare the clinical longevity of metallic and fiberglass intraradicular posts in teeth with severely compromised crowns, utilizing randomized clinical trials and case reports published in the last eleven years. Material and Methods: The research was conducted on PubMed, Medline, Lilacs, and BBO databases using the first search strategy with the descriptors 'dental posts,' 'longevity,' 'fiberglass-reinforced posts' or 'metallic posts.' The second search strategy involved analyzing the references of articles identified by the first search. Both studies were carried out with stringent inclusion and exclusion criteria. Results: No statistically significant and clinically relevant differences in longevity were observed between metallic and fiberglass posts. Conclusion: The clinical success and durability of the restorative procedure using intraradicular posts primarily depend on the remaining amount around the post (ferrule), the type and position of the tooth in the arch (impacting the masticatory forces exerted on the restored tooth), and the correct application of the cementation technique. It is noteworthy that fiberglass posts offer substantial advantages by presenting a modulus of elasticity similar to dental structure, ensuring a more homogeneous distribution of masticatory forces and reducing the risk of fractures. These findings have practical implications for material selection in restorative procedures involving intraradicular posts.(AU)

Objetivo: Esta revisão sistemática visa comparar a longevidade clínica de pinos intrarradiculares metálicos e de fibra de vidro em dentes com coroas severamente comprometidas, através de estudos clínicos randomizados e relatos de casos, publicados nos últimos onze anos. Material e Métodos: A pesquisa foi conduzida nas bases de dados PubMed, Medline, Lilacs e BBO, utilizando a primeira estratégia de busca com os s 'pinos dentais' e 'longevidade' e 'pinos reforçados com fibra de vidro' ou 'pinos metálicos'. A segunda estratégia de busca consistiu na análise das referências dos artigos identificados pela primeira estratégia. Ambos os estudos foram delineados com critérios rigorosos de inclusão e exclusão. Resultados: Não se constataram diferenças estatisticamente significativas e clinicamente relevantes na longevidade entre pinos metálicos e de fibra de vidro. Conclusão: O êxito clínico e a durabilidade do procedimento restaurador empregando pinos intrarradiculares dependem primordialmente da quantidade de remanescente ao redor do pino (férula), do tipo e posição do dente na arcada (o que impacta nas forças mastigatórias exercidas sobre o dente restaurado) e da aplicação correta da técnica de cimentação.Destaca-se que o pino de fibra de vidro oferece vantagens substanciais ao apresentar módulo de elasticidade similar à estrutura dentária, assegurando uma distribuição mais homogênea das forças mastigatórias e reduzindo o risco de fraturas (AU)

Fracture resistance of extensive amalgam restorations retained by pins, amalgapins and amalgam bonding agents.

This in-vitro study compared the resistance of extensive amalgam restorations retained by either four Regular TMS Link Plus pins, four amalgapins, Amalgambond Plus, Amalgambond Plus with HPA, Scotchbond Multi-Purpose Plus, PQ Amalgam, Panavia F 2.0, All-Bond 2 or Resinomer. Ninety caries-free third molars were embedded in acrylic resin and their occlusal surfaces reduced to within 2 mm of their CEJ. Tytin amalgam alloy was hand-condensed into copper band matrices reinforced with modeling compound after placement of mechanical retention or application of the amalgam bonding agents. Modeling compound and copper bands were removed after 24 hours, and the restorations were adjusted to produce specimens 5 mm in height with a 1 mm bevel on the occlusal-axial surface. The specimens were stored in 100% humidity for one month followed by immersion in de-ionized water for 24 hours at 37 degrees C. The specimens were loaded in compression at a 45 degrees angle in an Instron Universal Testing Machine at a crosshead speed of 0.02 inches/minute. The mean failure loads and standard deviations recorded in Newtons were as follows: Amalgambond Plus with HPA 2160N (380), Scotchbond Multi-Purpose Plus 1900N (380), four Amalgapins 1770N (340), PQAmalgam 1660N (270), Panavia F 2.0 1620N (440), Amalgambond Plus 1570N (390), four Regular TMS Link Plus Pins 1325N (406), All-Bond 2 1300N (390) and Resinomer 1245N (310). A one-way ANOVA and Tukey post hoc analysis indicated all amalgam bonding agents were statistically equal to either four Regular TMS Link Plus pins orfour amalgapins.

Radiological location monitoring in skeletal anchorage: introduction of a positioning guide.

BACKGROUND AND OBJECTIVE: As the insertion of miniscrews necessarily involves the risk of damaging the hard and soft tissues, particular attention must be paid to the diagnostics carried out prior to surgery, which include checking the insertion site radiologically by applying positioning devices. The placement of many common radiological positioning guides is difficult and time-consuming, and some varieties must be specially constructed at great cost, which led us to develop in this study a simple and easily applicable X-ray aid offering the mandatory safety features in terms of reliability and forensics. We aimed to design a device as small as possible to avoid as many falsely-positive and falsely-negative findings as possible with not-100% orthoradial dental films. We also wanted the device to be applicable in all potential insertion areas. MATERIALS AND METHODS: We initially performed a thorough literature research for suggestions for radiological positioning guides in pre-operative diagnostics. Based on those descriptions, we fabricated two common positioning devices, which we then applied and tested clinically regarding their handling, general applicability, and quality. To meet the stringent demands made of pre-operative radiological diagnostics, we developed a positioning guide with probing function ("X-ray pin"). Its applicability and diagnostic value were examined in a clinical study of prospective design. RESULTS AND CONCLUSIONS: Our radiological positioning device has a total length of 3.5 mm and has a ball on its end, thus resembling conventional pins in principle. Due to its conical form, the device can be easily placed in the mucosa at the designated insertion site. The X-ray pin is reliably stable in position, guaranteeing an accurate assessment of the designated miniscrew position. There is no need for advance bending; or for later adjustment and attachment attempts. The pin can be inserted in all regions, including the palatal area. Our X-ray pin proved to be an easily affordable, clinically simple, and safe-to-apply alternative.

Resin pins: a novel composite resin concept for treatment of posterior teeth--technical presentation.

With the evolution of bonding systems, various techniques have been proposed to reduce polymerization shrinkage and postoperative sensitivity in posterior direct resin restorations. It has been noted that the result could be improved using various layers, due to the contractions that occur proportionally to the quantity of material and the intensity of the curing light during polymerization. This article reviews the use of small, prepolymerized composite resin pearls or inserts compressed against the surface of the tooth wall to reduce the volume to be polymerized. The use of resin pins enables superior bonding to the dental structure, incrementing the marginal adaptation and reducing postoperative sensitivity.

The effects of TiO2 nanotubes on bond strength and radiopacity of a self-adhesive resin cement in self-curing mode / Os efeitos de nanotubos de TiO2 na resistência de união e radiopacidade de um cimento resinoso auto-adesivo no modo auto-polimerizável

Objective: The aim of this in vitro study w as t o analyze the influence of the titanium dioxide nanotubes i n a self-cure mode polymerization of a dual resin luting agent through push out bond strength and radiopacity tests. Material and Methods: After mixed with a commercial du al self-adhesive resin cement, three concentrations o f tit anium dioxide nanotubes (0.3, 0.6, and 0.9% by weight) we re analyzed in self-curing mode. T he bond strength to bovine root dentin and fi berglass posts was assessed with the push out bond str ength t est and was evaluated in three thirds (cervical, middle and apical) (n=10), followed by failure mode analysis (SEM), and the ISO standard 9917-2 was followed for radiopacity test (n=10). Data were statistically analyzed by one-way ANOVA test, followed by Tukey's test (α=0.05). Results: Reinforced self-adhesive resin cement with 0.6% titanium dioxide nanotubes showed significant difference compared to the control gr oup for push out test (p=0.00158). The modified groups did not s how significant difference among thirds (p=0.782). Radiopacity sh owed higher value for group w ith 0.9% titanium dioxide nanotubes in comparison w ith control group (p<0.001). Conclusion: The addition of titanium dioxide nanotubes to a self-adhesive resin cement increased the bond strength to dentin and radiopacity values in the self-cure polymerization mode (AU)

Objetivo: O objetivo deste estudo in vitro foi analisar a influência de nanotubos de dióxido de titânio na polimerização química de um agente cimentante resinoso dual através de testes de resistência à união e radiopacidade. Material e Métodos: Após misturado com um cimento resinoso auto-adesivo comercial, três concentrações de nanotubos de dióxido de titânio (0,3, 0,6 e 0,9% em peso) foram analisadas. A resistência da união para a dentina da raiz bovina e os pinos de fibra de vidro foi avaliada pelo teste de push-out e avaliada em três terços (cervical, médio e apical) (n = 10), seguido pelo análise de modo de falha (MEV) e a norma ISO 9917-2 foi seguido para teste de radiopacidade (n = 10). Os dados foram analisados estatisticamente pelo teste ANOVA um fator seguido do teste de Tukey (α = 0,05). Resultados: O cimento resinoso auto-adesivo reforçado com nanotubos de dióxido de titânio a 0,6% mostrou diferença significativa em comparação com o grupo controle para teste de push-out (p=0,00158). Os grupos modificados não mostraram diferença significativa entre os terços (p=0,782). A radiopacidade mostrou maior valor para o grupo com nanotubos de dióxido de titânio 0,9% em comparação com o grupo controle (p<0,001). Conclusão: A adição de nanotubos de dióxido de titânio a um cimento resinoso auto-adesivo aumentou a os valores de resistência de união à dentina e radiopacidade no modo de polimerização química do agente cimentante (AU)

In vitro fracture resistance of endodontically-treated maxillary premolars.

UNLABELLED: Many endodontically-treated teeth require quick, simple, low-cost restorations. This study evaluated the effect of horizontal pins and flowable composites on the fracture resistance of endodontically-treated maxillary premolars directly restored with resin composite. In this in vitro study, 64 intact human maxillary premolars, extracted for orthodontic reasons, were randomly divided into four groups of 16. Standard access cavities were prepared in such a way that the buccal cusp had a buccolingual thickness of 3 mm measured at the height of contour. The palatal cusp was reduced to 1.5 mm coronal to CEJ. The specimens were prepared as follows: Group 1: resin composite restoration without horizontal self-threading pins or flowable composite (control group). Group 2: resin composite restoration without horizontal self-threading pins but with a 2 mm thickness of the flowable composite. Group 3: resin composite restoration with two horizontal self-threading pins in the buccal cusp but without flowable composite. Group 4: resin composite restoration with two horizontal self-threading pins in the buccal cusp and flowable composite with a thickness of 2 mm. Subsequent to thermocycling, all specimens were loaded to failure. The data were analyzed using a two-factor ANOVA test (alpha = 0.05). The maximum mean of fracture resistance was in Group 1 (632.86 +/- 119.46 N), and the minimum value was related to Group 3 (533.49 +/- 168.07 N). There was not a statistically significant difference between the groups (p > 0.05). CONCLUSION: Neither horizontal pin placement nor flowable composite had a significant effect on increasing the fracture resistance of endodontically-treated maxillary premolars restored with composite.

Mechanical versus chemical retention for restoring complex restorations: what is the evidence?

This article reports the findings from a study conducted to answer this research question: can adhesive resin liners provide retention that is the same as dentinal pins or pots and slots when restoring complex amalgam restorations? The study methodology consisted of two components: a review of the literature and a survey to assess methods and materials that general practitioners use in their clinical practice for restoring complex amalgam restorations. Even though a vast majority of the general practitioners surveyed reported using dentinal pins or pots and slots, the occurrence or frequency of use was under 50 percent. It was also reported from the survey that over half the respondents are using adhesive resin liners exclusively when restoring complex restorations. New and improved materials allow general practitioners to restore complex restorations without the risks associated with the placement of pins or pots and slots. A review of the available literature indicates that adhesive resin liners may be used as an alternative or adjunct to mechanical retention. Because of the improvements of bonding strength of adhesive resin liners, dentinal pins and pots and slots should not be the only methods considered when faculty assist students in the development of treatment plans for patients who need complex amalgam restorations.

The vented cast gold crown.

Excellence in clinical restorative dentistry may be defined in many ways. Occlusion, esthetics, and morphology are important but none of these factors is more important than longevity. Not all of us will enjoy the clinical success that Dr. Tucker did but the time-tested technique of venting is one way to help prolong the life of a full cast crown.

Use of a pin and bar-retained composite bridge in anterior tooth loss: a case report.

A pin and bar-retained composite bridge can be used to replace missing teeth in cases when minimal tooth reduction is desired and patients refuse implant surgery for psychological reasons. This case report describes the clinical procedure for a pin and bar-retained composite bridge as a conservative solution for replacing missing teeth. The location and width of the toothless region, the patient's occlusion state, and poor oral habits may significantly affect the success of this alternative treatment. Compared with other restorative systems, this conservative approach is a minimally invasive technique that has a minimal effect on adjacent teeth.

Mandibular fracture repair in a harbor seal.

A 30-year-old captive female harbor seal (Phoca vitulina) bit down upon a metal ring within a hoop-net normally used to assist in securing the seal for routine physical examination. Radiographic examination performed under general anesthesia revealed a unilateral closed fracture of the rostral left mandible between the first and second premolar teeth. The rostral fragment was displaced ventrally and slight laxity of the mandibular symphysis was noted. The fracture was repaired surgically using an oral dental acrylic splint incorporating circumferential mandibular cerclage wire. The mandibular symphysis was stabilized using interdental wire between the right and left canine teeth. The fixation device was removed following evaluation of radiographs that showed signs of bony union 12-months postoperatively.