ceramic and metal - ceramic restorations have been used for several decades by clinicians to provide esthetics and masticatory function2 . studies have shown various advantages of the ceramics , like color stability , radiopacity , coefficient of thermal expansion similar to that of dentin , good compressive and abrasive resistance , and esthetics1,14 . however , dental materials and adhesive interfaces are subjected to stress in the oral environment : masticatory forces , temperatures changes , saliva and ph changes11 . moreover , trauma and fatigue can cause fracture of the ceramic or destroy the ceramic - metal bond14 because this restorative material has a low tensile strength and a high modulus of elasticity with a brittle behavior1 . problems such as a high treatment cost , possible trauma to the restored tooth , difficulty of removing the restorations , and patient demand for a rapid case resolution , may occasionally delay the replacement of a fractured metal - ceramic restoration15 . intraoral repair of fractured ceramic restorations with composite resin restorative materials presents a substantial challenge for clinicians9 , and is also a viable alternative for patients because these restorations are difficult to remove2 and very expensive to be replaced14 . the techniques include surface preparation of the ceramics and silane treatment in the bonding procedure9 . the establishment of reliable and durable chemical bonds between dental ceramics and composite resin is of paramount importance3 . with the introduction of silane coupling agents , a durable solution to ceramic repair became possible , since these hybrids inorganic - organic compounds bond dissimilar materials , organic and inorganic , together11 . the bond between ceramic surface and composite resin can be created with hydrofluoric acid etching for generation of a micromechanically retentive surface and silane agents . a combination of sandblasting and hydrofluoric acid would produce the best surface for composite resin repair , however hydrofluoric acid alone can be considered adequate when preparing a ceramic surface14 . thus , dental professionals should use techniques that produce acceptable , simplified , low cost and quick repair of such restorations . this paper presents two cases of feldspathic ceramic repair using composite resin , with and without the fractured ceramic fragment , in a single clinical session without the need for laboratorial assistance , allowing for an esthetic and functional rehabilitation . a 45-year old female patient with a 9-unit metal - ceramic fixed partial denture presented with a fracture delamination of the buccal and part of the incisal surface of the maxillary left central incisor distal angle without the ceramic fragment ( figure 1 ) . after treatment proposal , in addition , the prosthesis had a good aspect with satisfactory marginal adaptation around the abutments and good periodontal health . the ceramic color ( a2 shade ) was selected using the vita classical shade guide ( vita zahnfabrik , bad sckingen , germany ) . for control of the oral cavity humidity and patient protection , an alternative field isolation was obtained with the aid of a rubber dam ( madeitex ltda , so jos dos campos , sp , brazil ) , cottons , gauzes and a lip expander ( lip expand ; indusbello , londrina , pr , brazil ) ( figure 2 ) . acid etching was performed with the application of 10% hydrofluoric acid ( porcelain conditioner ; dentsply ind e com . ltda , petrpolis , rj , brazil ) for 2 min on the feldspathic ceramic surface ( figure 3 ) . the gel excess was removed with moist gauze to avoid spreading of the product into the patient 's mouth , followed by water rinsing for 30 s and drying with an air stream and absorbent paper . special care was carried out at this step to avoid accidental exposure of soft tissues to the hydrofluoric acid due to the inherent risks of this product . one - bottle silane coupling agent ( silano , angelus , londrina , pr , brazil ) was applied over the etched region for 1 min ( figure 4 ) followed by the application of the scothbond multipurpose adhesive phase only ( 3m / espe , st . the adhesive layer was light cured with a led curing unit ( radii - e ; sdi , victoria , australia ) . a microhybrid composite resin ( 4 seasons ; ivoclar vivadent , liechtenstein , germany ) was inserted incrementally with a thin a2 dentin layer , followed by a2 enamel and translucent resin layer to repair the fractured angle ( figure 6 ) . after light curing the composite resin , finishing was performed with abrasive silicone polishing tips ( optimize , tdv dental , pomedore , sc , brazil ) ( figure 7 ) . after removing the rubber dam isolation , an occlusal evaluation was performed to check for any contacts in maximum habitual intercuspation of the anterior teeth and during protrusion movement . after 24 h , polishing and burnishing were done with silicon tips and felt discs ( felt wheels , tdv dental ) and polishing paste ( 7026 ; kg sorensen , barueri , sp , brazil ) to create a natural appearance of the repaired ceramic ( figure 8) . a 55-year old female patient with a 14-unit metal - ceramic fixed partial denture presented with a dislodgement of the ceramic portion from the metallic structure in the maxillary right canine , probably due to the fatigue of the ceramic structure overloaded during the excursive movements ( figure 9 ) . as previously described in case 1 , the replacement of an extensive fixed prosthesis is an expensive treatment , mainly in cases of single - element fracture , and so ceramic repair with composite resin is a viable solution . the shade of the microhybrid composite selected in this case was b2 dentin ( 4season ; ivoclar vivadent ) . a rubber dam ( madeitex ltda ) was placed between the abutments to protect the patient and to prevent the contamination of the surface with saliva . acid etching ( porcelain conditioner ; dentsply ) was performed on the ceramic fragment and on the prosthesis structure in the patient 's mouth for 2 min ( figure 10 ) . conditioner excess was removed with moist gauze and the region was rinsed with a water spray for 30 s followed by air drying . thereafter , the rubber dam was removed due to the difficulty in obtaining a correct positioning of the ceramic fragment , and the area was protected with gauze and cottons rolls . the union was promoted with a silane agent ( silano , ngelus ) , applied in the fragment and in the prosthesis for 1 min followed by the application of the scothbond multipurpose adhesive phase ( 3m / espe ) on the silanized area . the activation was carried by a led curing unit ( radii - e ; sdi ) . the composite resin was inserted in the two ceramic separated parts ( figure 11 ) . subsequently , the excursive movements were checked , reproducing the anterior and canine guidances to achieve a harmonic distribution of the occlusal contacts , eliminating overload of the restored denture and providing free mandibular movements without damaging contacts17 . prosthesis repair was finished , reestablishing esthetics and function to the patient ( figure 13 ) . a 45-year old female patient with a 9-unit metal - ceramic fixed partial denture presented with a fracture delamination of the buccal and part of the incisal surface of the maxillary left central incisor distal angle without the ceramic fragment ( figure 1 ) . after treatment proposal , in addition , the prosthesis had a good aspect with satisfactory marginal adaptation around the abutments and good periodontal health . the ceramic color ( a2 shade ) was selected using the vita classical shade guide ( vita zahnfabrik , bad sckingen , germany ) . for control of the oral cavity humidity and patient protection , an alternative field isolation was obtained with the aid of a rubber dam ( madeitex ltda , so jos dos campos , sp , brazil ) , cottons , gauzes and a lip expander ( lip expand ; indusbello , londrina , pr , brazil ) ( figure 2 ) . acid etching was performed with the application of 10% hydrofluoric acid ( porcelain conditioner ; dentsply ind e com . ltda , petrpolis , rj , brazil ) for 2 min on the feldspathic ceramic surface ( figure 3 ) . the gel excess was removed with moist gauze to avoid spreading of the product into the patient 's mouth , followed by water rinsing for 30 s and drying with an air stream and absorbent paper . special care was carried out at this step to avoid accidental exposure of soft tissues to the hydrofluoric acid due to the inherent risks of this product . one - bottle silane coupling agent ( silano , angelus , londrina , pr , brazil ) was applied over the etched region for 1 min ( figure 4 ) followed by the application of the scothbond multipurpose adhesive phase only ( 3m / espe , st . the adhesive layer was light cured with a led curing unit ( radii - e ; sdi , victoria , australia ) . a microhybrid composite resin ( 4 seasons ; ivoclar vivadent , liechtenstein , germany ) was inserted incrementally with a thin a2 dentin layer , followed by a2 enamel and translucent resin layer to repair the fractured angle ( figure 6 ) . after light curing the composite resin , finishing was performed with abrasive silicone polishing tips ( optimize , tdv dental , pomedore , sc , brazil ) ( figure 7 ) . after removing the rubber dam isolation , an occlusal evaluation was performed to check for any contacts in maximum habitual intercuspation of the anterior teeth and during protrusion movement . after 24 h , polishing and burnishing were done with silicon tips and felt discs ( felt wheels , tdv dental ) and polishing paste ( 7026 ; kg sorensen , barueri , sp , brazil ) to create a natural appearance of the repaired ceramic ( figure 8) . a 55-year old female patient with a 14-unit metal - ceramic fixed partial denture presented with a dislodgement of the ceramic portion from the metallic structure in the maxillary right canine , probably due to the fatigue of the ceramic structure overloaded during the excursive movements ( figure 9 ) . as previously described in case 1 , the replacement of an extensive fixed prosthesis is an expensive treatment , mainly in cases of single - element fracture , and so ceramic repair with composite resin is a viable solution . the shade of the microhybrid composite selected in this case was b2 dentin ( 4season ; ivoclar vivadent ) . a rubber dam ( madeitex ltda ) was placed between the abutments to protect the patient and to prevent the contamination of the surface with saliva . acid etching ( porcelain conditioner ; dentsply ) was performed on the ceramic fragment and on the prosthesis structure in the patient 's mouth for 2 min ( figure 10 ) . conditioner excess was removed with moist gauze and the region was rinsed with a water spray for 30 s followed by air drying . thereafter , the rubber dam was removed due to the difficulty in obtaining a correct positioning of the ceramic fragment , and the area was protected with gauze and cottons rolls . the union was promoted with a silane agent ( silano , ngelus ) , applied in the fragment and in the prosthesis for 1 min followed by the application of the scothbond multipurpose adhesive phase ( 3m / espe ) on the silanized area . the activation was carried by a led curing unit ( radii - e ; sdi ) . the composite resin was inserted in the two ceramic separated parts ( figure 11 ) . subsequently , the excursive movements were checked , reproducing the anterior and canine guidances to achieve a harmonic distribution of the occlusal contacts , eliminating overload of the restored denture and providing free mandibular movements without damaging contacts17 . prosthesis repair was finished , reestablishing esthetics and function to the patient ( figure 13 ) . ceramic fractures may result from trauma4 , inadequate occlusal adjustment4,12 , parafunctional habits12 , flexural fatigue of the metal substructure12,13 , incompatibility of the coefficient of thermal expansion between the ceramic and the metal structure5 , failures in the adhesive bonding12 , inadequate tooth reduction during dental preparation4,13 , porosities in the ceramic12,13 , and inappropriate coping design4,12,13 . the purpose of any restorative technique is to facilitate the re - adaptation to a healthy condition that is momentarily damaged18 . in situations of fractured ceramic prosthesis , the possibility of ceramic repair with composite resins is an applicable approach that can restore esthetics and function to the patient in an inexpensive and rapid way . ceramic failures have been reported as the second greatest cause for the replacement of restorations after dental caries10 . furthermore , failures occur most frequently in regions that are quite visible , compromising esthetics13 . the goal of this clinical report was to demonstrate the potential of repairing ceramics with composite resin . clearly , the long - term results depend on the correct execution of the techniques and perfect occlusal adjustment . adequate bond between ceramics and composite resins is achieved with a silane coupling agent and an adhesive . the treatment with a silane agent contributes to covalent bond formation between the ceramic surface and the composite , and it also improves wetting of the ceramic surface for the composite3 . some studies have shown no differences between the use of one - bottle and two - bottle silane couplers , since an increase in the bond - strength of ceramics and composites was observed in both systems after a period of water storage3 . in addition , a bonding agent is usually applied with the expectation of penetration of monomers into roughened composite surfaces as well as , production of a surface unpolymerized layer after a short of period of light exposure8 . the use of simplified one - bottle adhesives is not justified because the primer is not needed here , only the adhesive phase of a conventional 3-step system . a 2-step adhesive is not the best choice because as the viscosity is greater , the penetration into the abraded surface presents more difficulty8 . in addition , a conventional adhesive system produces a best bonding when ceramics are repaired with composites6 . therefore , in order to obtain a satisfactory bond between the ceramic and the composite , conditioning must be performed in the etchable ceramics followed by application of a silane coupling agent in a way to increase the surface energy allowing for a reliable adhesion . it must be kept in mind that surface wetting is an important prerequisite for adhesive bonding11 and , furthermore , the application of an adhesive layer to the treated area is essential to fill the microporosities before the insertion of a viscous material like a composite resin . on the other hand , in cementation processes of all ceramic restorations with resin cements , the application of adhesives in the ceramic is not necessary due to the better wetting of surface obtained with these flowable materials19 . furthermore , the use of resin cements as way to bond large ceramics fragments as seen in case 2 is not indicated because a great amount of ceramic structure was lost with mismatch between the fragment and the prosthesis . the cementation with resin cement in this case would impair the adaptation of the fragment in the correct position . in this way , composites resins are preferred in these situations as they present greater viscosity , facilitating the ceramic repair . repairs made on multiple substrates may behave differently than those made only on a ceramic surface . in both cases presented in this article , cohesive and cohesive / adhesive fractures of ceramic were observed and satisfactory results were reached after surface conditioning and silane coupler application followed by repair with composite resin . however , when fractures of metal - ceramic prosthesis occur with metal exposure , minute resin tags are left on the metal surfaces and because of these tags , the fractures are categorized as adhesive failures making the repair more difficult . in these cases sandblasting with 30-m silica coated aluminum - oxide particles ( cojet sand , 3m - espe , seefeld , germany ) have shown satisfactory results7,15 . another possible alternative for these situations is the use of clearfil se bond ( kuraray co ltd , tokyo , japan ) which only requires surface sandblasting and correct product application . however , both materials are costly15 , which can make their use unviable in some clinical situations . repair of ceramic fractures with composite resin results in a reduced clinical time and less treatment sessions for the patient . moreover , this procedure restores esthetic and function in an easy , inexpensive and rapid form . the treatment option described herein is not intended to be preferred instead of a more definitive treatment for cases of fractured ceramic , that is , denture replacement ; the idea is to present a cost - effective alternative for patients who can not afford a new metal - ceramic prosthesis . the repair performed with composite resin is an esthetic and functional alternative when extensive fixed partial dentures can not be replaced .
the esthetic and functional rehabilitation of patients with multiple missing teeth can be performed with several techniques and materials . 
 ceramic restorations provide reliable masticatory function and good esthetics . 
 however , fracture can occur in some cases due to their brittle behavior . in some cases , the replacement of an extensive prosthesis is a problem due to the high treatment cost . in this paper , 
 two cases are presented , in which fractures occurred in extensive metal - ceramic fixed partial dentures , and their replacement was not possible . 
 ceramic repair was chosen and the sequences of treatment with and without presence of the ceramic fragment are also discussed . 
 the cases illustrate that , in some situations , fractured metal - ceramic partial dentures can be successfully repaired when prosthetic replacement is not a choice . 
 prosthodontists must use alternatives that allow a reliable repair to extensive metal - ceramic fixed partial dentures . 
 surface preparation of the ceramic with hydrofluoric acid in conjunction with a silane coupling agent is essential for a predictable bonding of composite resin . 
 the repair performed with composite resin is an esthetic and functional alternative when extensive fixed partial dentures can not be replaced .