Composite vs Compomer Restorative Materials: Properties, Applications, and Clinical Uses

 

Composite & Compomer Restorative Materials

Dental amalgam fillings were frequently used in paediatric dentistry due to its simple technique, moderate moisture control and low cost. (Fuks, 2002). Up until the last decade, extensive research about the hazards of the mercury content in amalgam have developed concerns about murcury toxicity. (Fuks, 2002). Those apprehensions together with advancements in tooth-colored materials raised concerns on the use of amalgam restorations in pediatric dentistry. (Fuks, 2002).

This led to changes in the utilization of amalgam in dental communities, and to the transition to use tooth-colored fillings as alternative materials for carious teeth restoration(Zwicker et al., 2014) such as dental composite, compomers, Glass Ionomer cement(GIC) and resin modified GIC. (Zwicker et al., 2014).

In this paper however we are going to focus on dental composite and compomers composition, classifications and their applications in paediatric dentistry.

HISTORY OF COMPOSITE

In 1936, the use of  poly(methylmethacrylate) (PMMA) as a denture material was first recorded. (Chan et al., 2010). In 1960s where R. L. Bowen led the invention of composites from Bis-GMA (bisphenol A-glycidyl methacrylate). (Rueggeberg, 2020).

Recently, the popularity and predictability of dental composite resin material have increased. (Velo et al., 2016). Surpassing the esthetics of other dental fillings with preservation of tooth structure in relative to indirect fillings, ability to repair and lower cost comparatively. (Fagundes et al., 2006). Made composite fillings the preffered choice of restorative material. (Fagundes et al., 2006).

COMPOSITION OF COMPOSITE

Classically, a resin composite is composed of three major parts ; resin matrix and cross-linking agents, inorganic fillers, coupling agent. (Makvandi et al., 2019). Additionally, inhibitors E.g. Butylated Hydroxytoluene are used to prevent spontaneous polymerization. (Klauer et al., 2019).  On the other hand, several initiator-activator systems are added to the composite for the polymerization reaction to take place such as Camphorquinone. (Klauer et al., 2019).

 

RESIN MATRIX

Organic resin matrix consists of the monomers that bond together to form a  solid polymer in a proccess called polymerization. (Klauer et al., 2019). It is composed of bisphenol glycidylmethacrylate(BIS-GMA) which functions as the base of the composite. (Klauer et al., 2019). Diluents such as methylmethacrylate(MMA),   bisphenol dimethacrylate(BIS-DMA)  plus urethane dimethacrylate(UDMA)  are inserted in composite to increase flow and handling characteristics of the composite. (Klauer et al., 2019). Cross link diluents like triethylene glycol dimethacrylate(TEGDMA) and ethylene glycol dimethacrylate(EGDMA) are also added to the resin matrix because it can accept pigments to form a tooth colored polymer. (Makvandi et al., 2019).Resin matrix was shown to be responsible for the setting contraction/polymerization shrinkage of composite filling material. (Makvandi et al., 2019).

In the past several decades cytotoxicity and genotoxicity of methacrylate related to methacrylate uncured monomers on the pulp tissue has been confirmed. (Zhou et al.,  2019). However, based on current evidence dental sealants or composites with low-level BPA causes no known health hazards. (American Dental Association, 2011).

 

INORGANIC FILLER

Composite fillers are found in different sizes and are made of different materials such as Silicon dioxide Colloidal silica, Quartz. (Hervás García et al., 2006). Silicate glass in composite fillers usually  contain barium, strontium, and zirconium which acts as Radio-opaquers this allow the composite to be visible under X-ray. (Hervás García et al., 2006)

Inorganic fillers function as support for the resin matrix, bringing about, increased toughness, strength, and decreased wear.(Hervás García et al., 2006). Increasing the number of fillers show decrease in polymerization contraction and decrease in thermal expansion and shrinkage. (Zhou et al., 2019). Additionally, fillers provide superior manipulation by enhancing the viscosity, decrease the water sorption and staining. (Zhou et al., 2019).

SILANE COUPLING AGENT

Silane couplng agent acts by joining the resin matrix and the inorganic fillers. (Lung & Matinlinna, 2012). This mediator bonds with methacrylate groups of the resin matrix to produce siloxane bond and hydroxyl groups of the filler. (Lung & Matinlinna, 2012).

COMPOSITE CLASSIFICATION 

In this section we are going to classify composite according to filler size, curing modes and clinical applications.

COMPOSITE-FILLER SIZE

A wide range of dental composite filler sizes were developed such as Macrofill-10-50μm, Minifill-0.1-1.1μm, Microfill 0.05-0.5μm, Nanofill 0.005-0.01μm and Hybrids 10–50 μm & 10–50 nm. (Lutz & phillips, 1983).

Macrofill composite

Due to the high filler-resin ratio, with Filler loading of 70-80% by weight. (Donly & Browning, 1992). This allow macrofill composite to sustain high compressive strength and low coefficient of thermal expansion. (Donly & Browning, 1992).

Clinical considerations of using macrofill composite include polishing difficulties, rough surface that tends to stain(Donly & Browning, 1992).and poor resistance to occlusal wear due to selective wear of resin matrix. (Donly & Browning, 1992).

Microfill composite

Microfill composite was fostered to overcome rough surfaces of macrofill resin composites with two hundred to three hundred times smaller fillers than the filler in macrofill composite. (Buen et al., 2007). Smoother surface was reported thanks to Colloidal silica microfillers. (Buen et al., 2007). Better aesthetics and polish-ability was also reported as an advantage of microfill composites. (Buen et al., 2007). However, in terms of compressive and flexural strength, it shows reduced physical and mechanical qualities to conventional composites.(Zhou et al.,  2019).

 

Nanofill composite

Developed in effort to have better smoothness of surfaces and to enhance physical and mechanical qualities of traditional composites. (Rinastiti et al., 2010). Due to the fact that nanofill composite have higher filler volume, the physical and mechanical qualities are superior to traditional composite. (Rinastiti et al., 2010). it also stood out with the best aesthetics and surface smoothness in composite. (Rinastiti et al., 2010).  However, difficulty in adaptation of nanofill composite to the cavity margins were observed due to high filler content. (Rinastiti et al., 2010).

Hybrid composite

Developed in an effort to combine the properties of both macrofilled and microfilled fillers. (Rinastiti et al., 2010). Composed of 2 different sizes of fillers (0.5–1.0 μm and 10–50 nm); colloidal silica which present in concentrations of 10 – 20%  and heavy metal glasses constituting of 75%. (Zhou et al.,  2019). Hybrid composite features less thermal expansion and higher compressive strength. (Zhou et al.,  2019).

However, it presents increased polymerization contraction due to a higher content of diluent monomer which governs the handling and viscosity of resin composition. (Chan et al., 2010).  In contrast, paralleled to the inadequate range of shades of early macrofilled and microfilled composites. (Zhou et al.,  2019). Present hybrid composites with tailored opacity and translucency are idyllic for aesthetic tooth fillings of anterior teeth. (Hientze et al., 2015).

COMPOSITE ACCORDING-CURING MODES

A range of activation systems are utilized to generate a free radical that initiates the polymerization process. (Zhou et al.,  2019). Because it affects the kinetics of polymerization, they also affect the properties of the restoration. (Zhou et al.,  2019).

Composite curing is classified into; self-cured, Light-activated and Dual-cured composites. (Kwon  et al., 2015).

Chemically initiated composites contain activators for polymerization like benzoyl peroxide(BPO) and tertiary amines. (Shin & Rawls, 2009). Here hardening process of composite is activated by an oxidation–reduction initiator system at room temperature. (Shin & Rawls, 2009). On the other hand, Light-activated composites contain activators such as Camphorquinone(CQ) and amine complex initiation. (Shin & Rawls, 2009). This is initiated by either UV light or visible light absorption of energy activates the CQ and amine. (Shin & Rawls, 2009).

Curing lights

A dental curing light is a dental apparatus utilized for polymerization of light-cure resin-based composites. (Mallman et al., 2005). Light Emitting Diode (LED), Quartz-Tungsten-Halogen (QTH) and Plasma arc curing light (PAC) light are examples of different types of curing lights used in dentistry. (Mallman et al., 2005).

Tungsten-Halogen light curing unit were stumbled on as a more reliable method for polymerization. (Dunn & Bush, 2002), with wider emission spectrum and cure different photo-initiators. However, they produce loud noises because of the cooling fans, additionally, they have high start-up cost. (Mallman et al., 2005).

LED require less power to operate curing units because of their unfiltered, narrow emission spectrum. (Yoshikawa et al., 2001).Consequently, they may be powered with rechargeable batteries, making them available in lightweight and cheaper cost. (Yoshikawa et al., 2001).

Depth of cure and exposure time

Degree of conversion and power density is governed by the light absorption and scattering of light in resin composite. Consequently 1-2mm depth of curing is a standard for adequate curing intensity. (Yoshikawa et al., 2001). Light rarefication differs depending on opacity, filler size, filler concentration and pigment shade. (Yoshikawa et al., 2001). Darker shades require longer curing time. (Alpino et al., 2006). Curing light intensity can vary drastically, depending on quality and age of light source, light tip orientation and direction, distance between light tip and tooth, lastly, presence of contamination on the light source. (Alpino et al., 2006).

In spite of the many pros of light cured resins, self-cured resin composites can be used with consistent results as luting agent under metallic restorations. (Alpino et al., 2006).

Polymerization Shrinkage

Gab formation between the tooth surface and composite bonded interface caused by shrinkage stresses. (Davidson & Feilzer, 1997). This subsequently leads to marginal staining, postoperative sensitivity, secondary caries and finally restoration failure(Davidson & Feilzer, 1997). Composite resin exhibit shrinkage while hardening with average of 2% to 6% at 30 min. (Kleverlaan & Feilzer, 2005). Factors affecting polymerization shrinkage include ; the volume of filler content,Intensity of curing light, thickness of composite resin, shade, and opacity of composite. (Kleverlaan & Feilzer, 2005). Shrinkage is highest with ramp curing modes and high intensity modes, whereas it is lesser with step‑curing and low intensity modes. However, the most important factor regarding the effects of polymerization shrinkage is the C-factor. (Watts & Satterthwaite, 2008).

C-factor stands for the ratio of bonded to unbonded or free surfaces of the composite restoration to the tooth surface. (Watts & Satterthwaite, 2008).

This is calculated as bonded walls divided by unbonded walls. The higher the c-factor the more the susceptibility of the restoration for polymerization shrinkage. (Watts & Satterthwaite, 2008).

Class IV restoration is reported as the low-risk filling for polymerization shrinkage with c-factor of 0.2. On the other hand, Class I with C-factor 5 is at a comparatively high risk. (Van Dijken, 2010).

Longitevity of composite filling.

Multiple factors such as the size of the resin composite filling, tooth number/position and patient risk assessment for caries have been shown to affect the longevity of composite fillings.(Bohaty et al, 2013). In addition, properties of the material used, adequacy of the bond to the tooth surface and experience of the operator can determine the quality of the seal at the composite-tooth interface.(Bohaty et al, 2013).As a whole the general findings advocate that at least 60% of resin composite fillings will be sustained for more than 10 years when material and technique is used correctly. (Kubo, 2011).

COMPOSITE-CLINICAL APPLICATION

In this section we are going to classify composite according to their clinical use in different clinical scenarios.

Flowable Composite

Flowable composite was introduced in dentistry for the first time in 1996. (Garcia  et al., 2006). The reduced filler loading from 50–70% by volume to 37–53% (volume)(Baroudi & Rodrigues, 2015) allow decreased viscosity and increased flowability of the composite. (Baroudi & Rodrigues, 2015). Flowable composite can go in minute spaces or areas of a restorative cavity by an injection syringe, thus increase the operation simplicity and shorten the working time. (Baroudi & Rodrigues, 2015).

First-generation flowable  resin composites, were only applied as a cavity liner or pits and fissure sealants owing to its lower filler volume and its modulus of elasticity (Boruziniat et al., 2016).

Newer generations retain a broader range of purposes such as, preventive resin restoration(PRR), minimally invasive class III & class V restorations and abfraction lesions. (Baroudi & Rodrigues, 2015). However, flowable composites are suggested to be operated only in low-stress bearing fillings due to its low compressive and flexural strength compared to conventional composite. (Zhou et al., 2019).

Bulk-Fill Composites.

Conventional composite is classically cured every 1 mm increment, This type of composite was created to reduce the time consuming drawback of incremental technique in cavity filling. (Kim et al., 2015). Bulk-fill composites allow depth of polymerization to be sufficient for 4 mm increments by utilizing high translucent shades. (Zorzin et al., 2014) Complex activator systems are used to shorten the light curing time. (Orłowski et al., 2015). A study by Al-Harbi et al. (2015) found that bulk-fill composites offer improved cervical contact and comparable marginal quality of bulk-fill restoration versus incremental-fill class-II fillings.

Compomers - Polyacid modified resin composites

A combination of composite and glass ionomer cement(polyalkenoate acid and glass components). Compomers possess a dual-setting mechanism, of which the major setting reaction is the resin photopolymerization, then the acid–alkali reaction takes place in presence of water. (Pummer et al., 2020). Developed in faith of conveying the favourable qualities of resin composites and GIC. (Pummer et al., 2020). As a result of its ease of handling and fluoride release, compomers transpired quickly and received acceptability by the dental communities. (Ruse, 1999). However, compomers convey a number of drawbacks like brittleness, lower compressive strength, longer curing time, and water sensitivity. (Mousavinasab & Meyers, 2009). Compomers were also reported to have a high polymerization shrinkage(Mousavinasab & Meyers, 2009). A study by Moodley & Grobler (2003) found that resin modified GIC released larger volume of fluoride compared to compomers. When compomers were used as fissure sealants, compomer sealant showed a lower retention rate than conventional sealants.(Ram et al., 2005). Therefore, it was appropriate as a temporary sealant for molar teeth. (Ram et al., 2005).

Flowable compomer E.g. Dyract Flow are easily adapted to the cavity walls, are indicated for minimal invasive restorations and are used in marginal repair of resin restorations. (Ehlers et al., 2019).

In class I & II restorations, high success rates of 91.2% and 94% for Dyract compomer were achieved after 3 years. Class III restorations were also reported successful. (Ehlers et al., 2019). However, high fracture rate and its inferior aesthetics to composite discouraged its use in class IV restorations. (Ehlers et al., 2019).

Clinically, failure of compomers is related to poor moisture control, retention loss and secondary caries. (Kramer & Frankenberfer, 2015). However, under a correct application protocol like moisture control and compliance of the patient compomers demonstrated high success rates. (Kramer & Frankenberfer, 2015). Therefore, the patients must be judged individually specially in the deciduous dentition, according to the patient’s caries risk, tooth location and cavity shape. (Campagna et al., 2018).

 

DENTAL COMPOSITE IN PAEDIATRIC DENTISTRY

This section is going to talk about the procedure, relation and applications of composite in the paediatric dentistry.

Clinical procedure

Enamel cleaning

This is done by removing only the deposits on enamel surface such as, surface cuticle and stained pellicle. (Welbury et al., 2018). Cleaning can be done with multiple techniques like using prophy pastes, pumice slurry, grain diamond or sandblast discs. (AAPD, 2019)

According to the American Academy of Pediatric Dentistry (2019), rotating prophylaxis brush with fine grain paste is recommended preceding enamel etching. However, it is suggested that fluoride containing pastes must be contraindicated, as they lead to enamel surface further resist etching. (Kakaboura & Papagiannoulis, 2005). Furthermore, grinding of enamel is avoided because it can lead to superficial enamel (Aprismatic) removal. (Kakaboura & Papagiannoulis, 2005).This can compromise etching with scratch marks, debris, irregular etch pattern or coarse abrading effect on enamel surface. (Kakaboura & Papagiannoulis, 2005).

Enamel conditioning/etching

Etching patterns and itching times affects the resin bond strength. (Moore, 2019). trivial structural changes on the enamel surface were shown when exceeding 30 seconds of etching time. (Moore, 2019). Therefore, 37% phosphoric acid used for 15 sec on dentin and 30s on enamel (Selective etching) is recommended. (AAPD, 2019). Following etching, over-drying the tooth surface increased the risk of collagen fibrils collapse and lead to desiccating of the dentin. (AAPD, 2019). Thus, its only recommended to dry gently for 5 seconds. (Lenzi et al., 2017).

Dental Adhesive/Bonding 

Various systems were invented of which the most commonly used were Etch-and-rinse:  adhesive approach (Total Etch) and Self-etch adhesives. These bonding systems presently function as primers and adhesives. (Garcia-Godoy & Donly, 2014).

Etch-and-rinse adhesive system is used after etching procedure is done and tooth is rinsed. (Tsujimoto et al., 2017).

This system of adhesive agent includes the bond and primer. (Tsujimoto et al., 2017).

On the other hand, Self-etch adhesives were first an appealing alternative with less clinical steps (Tsujimoto et al., 2017). This system has an acidic resin which etches and bonds without the need for etching or rinsing procedure. (Tsujimoto et al., 2017).

Although, In-vitro studies reported inferior bond strength, milder etching effect & thinner bond interface to enamel surface compared with etch and rinse system using 37% phosphoric acid. (Lenzi et al., 2017).

It must be noted that after applying the adhesive, a gentle dry blow of air from dental syringe is recommended for 5 seconds to remove excess solvent and prevent pooling. (Moore, 2019). Curing time of the adhesive agent should be according to manufacturer instructions. (Moore, 2019).

Finishing & polishing

Finishing of composite to remove excess or high occlusion point is recommended with 12 or 30-fluted Carbide bur or fine diamond finishing burs. (AAPD, 2019). Polishing however is done to smoothen the surface of the composite restoration and reduce roughness which can facilitate plaque attachment. (Moore, 2019).

This is done with abrasive discs, rubber cups and points or diamond polishing paste. (Moore, 2019).

Composite and primary teeth

Due to the fact that composite mainly depend on micromechanical bond of etched enamel (Berry & Osbone, 2015) and primary teeth have thinner enamel structure compared to permanent teeth.(Berry & Osbone, 2015). Hence, lower retention rates of composite filling in primary teeth. (Berry & Osbone, 2015). Other factor to be considered is the lower mineralization of primary teeth dentin. (Chay et al, 2014). Therefore the etching proccess should be shortened to minimize the demineralization that will result from the formation of weak hybrid layer. (Chay et al, 2014).

Different composite clinical uses in Pediatric Dentistry:

They include but not limited to preventive resin restorations (PRR), Sandwich technique, Strip crowns, Composite in interceptive dentistry, Splint of traumatized teeth, Reattachment of anterior fractured teeth, Fissure sealant and composite in restorative dentistry. 

Preventive resin restorations (PRR)

Patients with low risk caries and teeth with shallow cavities can be restored with flowable composite. (Waggoner et al, 2002). This is done by placing a sealant restorative material over cavity prone pits and fissures that are not involved in the carious lesion preparation. (Moore, 2019). These include preparations that extend into enamel and are limited to pits and fissures without cavitation, or dentin involvement. (Garcia-Godoy & Donly, 2015).

Sandwich technique

This technique is used to combine the GIC flouride releasing and modulous of elasticity that is similar to dentin, with the strength and aesthetics of composite resins. (Lindberg, 2005). This technique is divided to open or closed sandwich. (Fabianelli et al., 2009). Open sandwich technique sometimes is utilized in Class II cavities. (Lindberg, 2005). A study by Van Dijken et al. (1999) reported that the success rate of open sandwich technique was similar to amalgam class II after 3 years. In class II open sandwich technique, the GIC must be placed under the contact point of the tooth to prevent washout and eventually open contacts. (Sidu et al., 2011). On the Other hand, Closed sandwich technique is utilised when the GIC is used as a base in class I restoration, Hence the name”closed”. (Darsan et al., 2018). Due to GIC and dentin similar modulus of elasticity, sandwich technique has shown to reduce stress formation around the dentin-restoration interface. (Loguercio et al., 2002).

Strip crowns

Strip crowns are one of the most aesthetic restorations used in restoring extensively decayed primary anterior teeth. (Kupietzky et al., 2003). In consequence, selecting the proper crown form and measuring mesio-distal width of the tooth is mandatory. (Welbury et al., 2018). We have various Indications of strip crown, that include multiple carious lesions that involve the incisal edge, extensive cervical lesions or erosions and after pulp therapy. (Moore, 2019). It was reported that resin composite SCs performed well for restoring primary incisors with large or multi surface caries. (Kupietzky et al., 2005). With 80% retention rate for periods of over 3 years. (Kupietzky et al., 2005). However, strip crown placement is challenging and its application is technique sensitive (Kupietzky, 2002), specifically if there is moisture contamination. (Mittal et al., 2016). That’s why Strip crowns are contraindicated in uncooperative patients, one surface caries lesion and anterior cross-bite patients. (Waggoner et al., 2002).

Composite in interceptive dentistry

In the hopes of pursuing a more hygienic, lower cost and less time-consuming space maintainer, fiber-reinforced composite was acquired as an alternative to metal band and loop in the mixed dentition. (Yuleri et al ., 2012). However, it was shown that the success rate of composite band and loop space maintainer is inadequate(Potgieter  et al., 2018), due to fracture of the loop or looseness of the band from the masticatory forces.(Potgieter  et al, 2018). Other uses of Fiber reinforced composite involve stabilization of luxated and avulsed teeth as a temporary prosthodontics appliance. (Yuleri et al ., 2012). Reinforced ribbon is bondable, biocompatible, aesthetic, translucent and easy-to-use. (Yuleri et al ., 2012). However, the evidence of success rate and longevity of this treatment is lacking in the literature and more randomized clinical trials are needed.

Splint of traumatized teeth

Composite splints were not recommended for traumatized teeth since they are rigid, brittle and susceptible to fracture and can lead to gingival irritation during removal of splint. (Kahler et al., 2016). Thus, composite and metal wire splints diameter 0.3-0.4 mm are the most commonly used in stabilization of traumatized teeth. (Kahler et al., 2016). However, some studies suggest the use of RMGIC particularly because it can be easy to apply and remove with no or minimal iatrogenic damage to the enamel. (Kahler et al., 2016).

Reattachment of anterior fractured teeth

Reattachment of fractured teeth provides an adequate treatment modality that can be the primary technique to restore fractured tooth with salvaged fragment after trauma. (Garcia et al., 2018)

Fragment and tooth are prepared with a minor bevel and flowable composite is placed to reattach and adapt the fragment to the remaining tooth structure. (Garcia et al., 2018). The use of flowable composite exhibited success rate of 88.9% in after 5 years follow up. (Sarapultsev, 2019).

Fissure sealants

One of the most important factors to determine the success of pits and fissure sealants is the bond between the sealant and tooth structure. (Dhillon et al, 2012). Some studies have suggested that using flowable composite as a pit and fissure sealant can be reliable. (Asefi et al., 2016);(Bagherian et al, 2018). However, use of flowable composite is associated with greater risk of microleakage (Singh & Pandey, 2011). Retentive forces of Resin based sealant is lower than glass ionomer sealant in moisture environment. (Gray et al, 1994). Therefore, using GIC based sealants is better and more cost effective approach. (Joshi et al., 2019).

Composite in Restorative dentistry

In class I cavity, there is strong evidence that composite restorations for are successful (AAPD, 2016). An observation period of 8 years, success rate was documented to be 79% in class I cavities in primary teeth (Bücher et al., 2015). The most frequently reported aetiology of   restoration failure was secondary caries caused by shrinkage. (Puckett et al., 2007).

In class II cavity, composite resin when compared to RMGIC shows higher resistance to wear, higher microhardness, and therefore relative functional success. (Van Dijken et al., 1999). RMGIC displayed superior performance and lower secondary caries incidence due to fluoride release (Jones & Taylor, 2018). Differences in survival rates of composite class II were very variable 59%- 95%. (Jones & Taylor, 2018). The differences in survival rates for class II resin composites were mainly due to cavity size. (zhou et al., 2019).

In class III, IV cavities, primary teeth interproximal restorations exhibited challenging cavity preparation due to the close proximity of the pulp horn to the inter-proximal surfaces, and their relative smaller clinical crown. (Waggoner et al, 2002). Therefore, the use of tooth coloured bonded restorative materials is recommended to minimize the extent of the preparation. (Waggoner et al, 2002).

Additionally, the high esthetics of composite resin further encourages their use in class III,IV and V in primary and permanent teeth when patient is cooperative with moisture control. (AAPD, 2019).

	Advantages	Disadvantages
RMGIC	•        Adhesive •        Aesthetics> GIC •        Simple to handle •        Release Fluoride	•        Water absorption •        Significant wear •        Technique sensitive
COMPOMER	•        Adhesive •        Aesthetic •        Simple to handle •        Fluoride release	•        Technique sensitive •        Less aesthetics than composite •        Less flouride release than RMGIC & GIC. •        Less wear resistance than composite
COMPOSITE	•        Adhesive •        Most Aesthetic •        Reasonable wear resistance	•        Technique sensitive •        Rubberdam is required •        Expensive
AMALGAM	•        Technique insensitive •        Durable •        Cheap •        Quick & simple	•        Non-Adhesive •        Require mechanical retentive preperation •        Environmental, Public hazards •        Unaesthetic

Conclusion

Success of the composite resin is multifactorial, contingent on the understanding of the physical properties, chemical properties of the material and the applications of individual class of composite. In addition, achieving adequate caries excavation during cavity preparation and proper technique of manipulation are subjective to the operator skill and knowledge. This together with consideration of the patient case selection and management of caries risk factors

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