Zinc Phosphate Cement Research Articles

Concepts of restoring endodontically treated teeth among dentists in Saudi Arabia

The purpose of this survey was to investigate the current concepts, opinions, techniques and materials used on how to restore the endodontically treated teeth (ETT) among dentists in Saudi Arabia. A self administrative questionnaire especially designed for this study was distributed among a conveniently selected sample. A total of 204 questionnaires were completed (Response rate = 30%). Irrespective of their occupational experience, 62% of the surveyed dentists considered the remaining tooth structure while restoration of ETT while 10% will always place a post in ETT. More than half of the surveyed dentists (52%) believed that a post reinforces ETT either always or sometimes. Majority of the participants agreed that ferrule effect will always (46%) or sometimes (32%) increase the fracture resistance of an ETT. Prefabricated posts were used by 53% and cast posts by 37% of all the participants. The use of parallel sided prefabricated posts, made of metal (29%) or non metal (29%), was the most preferred technique by the surveyed dentists. 60% of the participants agreed that 2/3rd of the canal should be used for the post length. Composite resin (57%) was preferred for core foundation, followed by amalgam (19%) among the participants. Posts are placed primarily with glass ionomer cement (48%), followed by resin cement (22%) and zinc phosphate cement (21%). The use of the posts was common and the belief that a post reinforces an ETT might explain the reason for its usage by the Saudi dentists. The use of prefabricated post, composite resin as core material and glass ionomer as luting cement is common, while restoring ETT by the Saudi dentists. Endodontic failure was thought to be the most common reason for failure of ETT by the Saudi dentists.

English

Oxide Eugenol (ZOE) is a material created by the combination of Zinc Oxide and Eugenol contained in oil of cloves. Acid-base reaction takes place within the mixture to form Zinc Eugenolate Chelate. The reaction is catalyzed by water and is accelerated by the presence of metal salts. ZOE can be used as a filling cement material in dentistry. Tissue tolerance to Zinc Oxide Eugenol is better as compared to other dental materials. The cement relieve pain due to reversible pulpitis because it is bacteriostatic, obtundent as well as antiseptic nature, they are well accepted by patients. The cements are good insulators and possess better sealing properties than zinc phosphate cements. Because of their poor mechanical properties, the conventional zinc oxide-eugenol cements are mainly used as temporary fixing cements. They are also used as gingival dressings, root canal sealers and also as impression materials.

CORONAL SEALING ABILITY OF COPALITE VARNISH WITH DIFFERENT INTERMEDIATE RESTORATIONS AS AN INTRA-ORIFICE BARRIER IN ENDODONTICALLY TREATED TEETH. A COMPARATIVE IN-VITRO STUDY

Background Coronal restorations having an effect on the outcome of root canal treatment. Objectives The aim of this study was to evaluate and compare sealing ability of three cement base materials with and without cavity varnish in the orifice of root canal systems after root-canal treatment. Methods The palatal root of extracted human maxillary first molar teeth were selected, after preparation and obturation three millimeters of coronal gutta-percha were removed from the coronal aspect of the root canal and divided randomly into six groups (6 roots each). Root canal orifices were restored with conventional glass ionomer cement, zinc polycarboxylate cement and zinc phosphate cement bases with and without cavity varnish. All the specimens were thermocycled for 100 cycles at 7°C – 55°C for 60 sec in each bath. They were immersed in the 1% methylene blue solution for 7 days, and then sectioned into longitudinal sections. The extent of dye penetration was measured using stereomicroscope. Data were analyzed statistically. Results All the materials leaked at the interface of restorative material-dentin wall. Glass ionomer cement with varnish sealed significantly better than the other groups.

Bevestiging van kronen en bruggen

A single- or multi-unit fixed dental prosthesis can be attached to the abutment teeth through mechanical retention and gap sealing or by adhesion. For sealing the gap, water-soluble cements are appropriate, such as zinc phosphate, polycarboxylate, and (resin-modified) glasionomer cement. Attachment through adhesion can be performed with composite cement. If the hard tooth tissue is prepared adequately, composite cement provides sufficient adhesion, but self-adhesive composite cement is now also available. For the adhesion of the composite cement to the restorative materials of the single- or multi-unit fixed dental prosthesis, surface sandblasting, silanizing, and tin coating and the application of a metal primer or chemically active composite are available. Cementing a single- or multi-unit dental prosthesis involves 3 phases: 1. Cleansing the single- or multi-unit dental prosthesis and the abutment tooth/teeth; 2. Preparing the hard tooth tissue, mixing the cement and placing the single- or multi-unit dental prosthesis; 3. Removing the excess cement.

Retentiveness of Metal Coping Luted to Teeth of Uremic Patients Undergoing Hemodialysis Using Five Different Luting Cements

This study aimed to assess the retention of metal copings luted to uremic teeth with five different luting agents. A total of 35 sound natural molars was collected from uremic patients and randomly assigned into five groups (n=7). The teeth were prepared for metal copings using diamond tips and water coolant. Metal copings with a loop on the occlusal surface were fabricated using base metal alloy (Rexillium III). The copings were luted using Fuji I, glass ionomer (GI); Fuji Plus, resin-modified glass ionomer (RMGI); Panavia F 2.0, resin cement; Rely X Unicem, self-adhesive cement (SA); and Adhesor, zinc phosphate cement (ZPh). All specimens were incubated at 37°C for 24 hours, conditioned in artificial saliva for 7 days, and then thermocycled for 5000 cycles (5°C-55°C). The dislodging force was measured using a universal testing machine at a crosshead speed of 2 mm/min. The mode of failure of the loaded adhesive copings was evaluated. Statistical analyses were performed using one-way analysis of variance and Tukey post hoc test. GI and SA cements had the highest and the lowest mean retentive strength, respectively (580.90±17.3, 406.6±12.7). There was no significant difference between ZPh, SA, and resin cements. These cements were inferior to GI and RMGI cements (p<0.05), which showed statistically similar retentive strengths. The results of this study support the use of glass ionomer and resin-modified glass ionomer cements for luting of metal copings to uremic teeth with retentive preparations.

Effect of eugenol-containing and resin endodontic sealers on retention of prefabricated metal posts cemented with zinc phosphate and resin cements

PurposeThe aim of this study was to compare the effects of two endodontic sealers on the retention of posts cemented with zinc phosphate or resin cement. Materials and methodsCrowns of 72 mandibular premolars were removed at the cementoenamel junction. Root canals were prepared and specimens were randomly divided into two groups of 36. In each group, 12 specimens were obturated with gutta percha only; 12 specimens with gutta percha/ZOE sealer and 12 specimens with gutta percha/AH26. In the first group, 10mm Post spaces were prepared with Peeso reamers size 4 and, size 5 stainless steel Paraposts were cemented in with zinc phosphate. In the second group, 10mm Post spaces were prepared with Fiber Lux size 5.5 drills and size 5 Paraposts were cemented with Panavia F2.0. After mounting in resin blocks, posts were pulled out by universal testing machine at 1mm/min and results were analyzed by two-way ANOVA and Dunnett test. ResultsMean forces (in Newtons) required to remove posts cemented with zinc phosphate in canals obturated without sealer, with ZOE, and with AH26 sealers were 270±83, 281±128 and 266±67, respectively; and for posts cemented with Panavia F2.0 were 520±290, 464±212 and 229±108, respectively. Statistical analysis showed that AH26 significantly reduced retention of posts cemented with Panavia F2.0 (p<0.05). ConclusionDifferent sealers had no significant effect on retention of posts cemented with zinc phosphate. However posts cemented with Panavia F2.0 showed reduced retention in canals obturated with AH26.

Effect of Post Length and Type of Luting Agent on the Dislodging Time of Metallic Prefabricated Posts by Using Ultrasonic Vibration

IntroductionThe purpose of this study was to determine and compare the times needed to dislodge prefabricated titanium posts of different luting lengths with various cements. MethodsEighty-one intact extracted, single-canal human teeth were selected and endodontically treated. Specimens were randomly divided into 9 groups, which were arranged according to the post space length (5, 7, and 9 mm) and cement type (zinc phosphate, glass ionomer, and resin cement). Titanium posts were cemented into the post spaces, and after 1 week of storage they were subjected to ultrasonic vibration. The dislodging times were recorded and analyzed by using the Kruskal-Wallis and Mann-Whitney tests (P < .05). ResultsA significant difference was observed between the dislodging times on the basis of post length and luting agent (P < .001). There were also significant differences between different cements luted with the same length posts (P < .001). Significant differences were observed between the 5-mm posts and both the 7- and 9-mm posts for each cement, but the differences between the 7-mm and 9-mm posts were not significant (P < .05). ConclusionsChanges in the cement type and post length alter the time required to dislodge a post with an ultrasonic device.

Students’ Perceptions of Materials and Techniques Used at European Dental Schools in the Education of Fixed Prosthodontics

The aim of this study was to explore the materials and procedures used by students in dental schools across Europe for teaching fixed prosthodontics. An online questionnaire, containing twenty-eight dichotomous, multiple-choice, and Likert scale rating questions, was sent to students in forty dental schools. After excluding dental schools in which less than 10 percent of the students responded, 775 questionnaires from ten schools remained for statistical analysis. Among these respondents, acrylic resin teeth were said to be the most commonly used material during preclinical practice (46-96 percent), and use of extracted teeth varied from 8 to 65 percent. At nine of the ten institutions, metal-ceramic was reported to be most commonly used for fixed dental prostheses. There was large variation in the type of finish line for a metal-ceramic fixed dental prosthesis: students at five institutions reported using a shoulder finish line, three a chamfer finish line, and two a shoulder-bevel finish line. A similar variation was observed with regard to the final cementation of metal-ceramic fixed dental prostheses: students at four institutions reporting most frequently using glass ionomer cement, with three using zinc phosphate cement and three using carboxylate cement. The responding European dental students varied considerably in their opinions about whether they were preclinically properly trained for the first preparation on a patient and in their overall rating of their education in fixed prosthodontics. Responding students in the United Kingdom, Sweden, and Nijmegen, The Netherlands, rated their fixed prosthodontics training overall the highest. Overall, this study found a wide variation amongst dental schools with regard to their education in fixed prosthodontics and their rating of this teaching.

Forensic or archaeological issue: is chemical analysis of dental restorations helpful in assessing time since death and identification of skeletonized human remains?

In 2011, small mass grave with completely skeletonized remains was discovered in Belgrade suburb. An eyewitness claimed that skeletons belonged to German soldiers killed in WWII. Anthropologists were engaged to investigate whether the skeletal remains correspond to the indicated German group or represent more recent case requiring court trial. Numerous dental restorations were noticed. Owing to the fact that different dental materials were used in dental practice at certain times, the aim of this study was to explore whether analysis of dental restorations could help in identification and estimation of time since death. Inductively coupled plasma optical emission spectrometry revealed that dental fillings corresponded to copper amalgam, conventional silver amalgam, silicophosphate cement, and zinc phosphate cement. Chemical results combined with anthropological and historical facts suggest that the individuals lived before the 1960s in country with well-developed dental service at that time. Therefore, chemical analysis of dental fillings was useful to distinguish between skeletal remains that are too old to be of forensic interest and the remains relevant to legal investigations.

An in vitro atomic force microscopic study of commercially available dental luting materials

The aim of this in vitro study was to compare the surface roughness parameters of four different types of dental luting agents used for cementation of implant restorations. Five specimens (8 mm high and 1 mm thick) of each cement were made using metal ring steelless molds. Atomic Force Microscope was employed to analyze different surface texture parameters of the materials. Bearing ratio analysis was used to calculate the potential microgap size between the cement and implant material and to calculate the depth of the valleys on the cement surface, while power spectral density (PSD) measurements were performed to measure the percentage of the surface prone to bacterial adhesion. Glass ionomer cement showed significantly lower value of average surface roughness then the other groups of the materials (P < 0.05) which was in line with the results of Bearing ratio analysis. On the other side, PSD analysis showed that zinc phosphate cement experience the lowest percentage of the surface which promote bacterial colonization. Glas ionomer cements present the surface roughness parameters that are less favorable for bacterial adhesion than that of zinc phosphate, resin-modified glass ionomer and resin cements.

Comparative study of retention of fiber-reinforced post at middle and cervical one thirds of root canal cemented by polycarboxylate and zinc phosphate cements measured at different storage times

Background: The purpose of this study was to compare regional bond strength at middle and cervical thirds of the root canal among glass fiber-reinforced composite (FRC) endodontic posts cemented with different cements, using the push-out test to compare the performance (retention) of two types of luting cements; polycarboxylate cement and Zinc phosphate cement used to cement translucent fiber post and to compare the result of the push-out test at different storage times;1 week ,1month and 2 months. Materials and methods: Ninety caries-free, recently extracted single-rooted human teeth with straight root canals was used in this study, The root canals were endodontically instrumented at a working length of 0.5 mm from the apex by means of conventional instruments for hand use (Dentsply, Switzerland) up to size 35.then root canal filling was performed followed by post space preparation up to 8mm including cervical and middle one third of root canal then the fiber post was cemented into canal post space then the root was sectioned to get cervical (4 mm in length) and middle (4 mm in length) thirds ,these thirds were examined by push out test to get values of retention of fiber post inside these canal thirds . Results and Conclusions: The results of this study has been showed that there was no significant differences between push out bond strength between fiber post and root at cervical third as compared with middle third when using polycarboxylate cement or Zinc phosphate cement to cement the fiber post to the canal walls and the results showed that there was no significant differences in push out bond strength for polycarboxylate or Zinc phosphate cement after one and two months but there was highly significantly increase in push out bond strength for resin cements used to cement the fiber post to the root canal after one and two months

Detection of looseness degree of dental posts using natural frequency analysis

This study examines the relationship between the retention force and natural frequency of dental posts cemented with zinc phosphate cement. Forty-two decoronated maxillary incisors were collected and embedded in resin blocks. The 7-mm post spaces were prepared for all test samples prior to cementing the 13-mm Para-Posts with zinc phosphate cement. The natural frequency values and retention forces of the zinc phosphate cement-cemented Para-Posts in various liquid/powder mixing ratios were measured. Thereafter, the natural frequency values of the zinc phosphate cement-cemented posts were continuously detected during ultrasonic vibration. Moreover, both the natural frequency values and the dislodgement forces in response to ultrasonic vibrations were measured for the pretreated post samples. Results showed that the natural frequency values of the posts significantly decreased from 8.8 ± 0.8 to 5.0 ± 0.5 kHz (P < 0.05) before and after ultrasound treatment, respectively. The natural frequency values and the dislodgement forces of tested posts had a highly linear relationship (R² = 0.99, P < 0.05). These findings suggest that natural frequency is a variable for monitoring the stability status of zinc phosphate cement-cemented dental posts.

In vitro comparisons of casting retention on implant abutments among commercially available and experimental castor oil-containing dental luting agents

Although cement-retained implant prostheses are widely used, the quantification of optimal retention remains controversial, and new dental luting agents should be evaluated. The purpose of this study was to compare, in vitro, the casting retention on implant abutments after cementation with 3 commercially available luting agents and an experimental luting agent (castor oil polyurethane, COP) with variable weight percentages (wt%) of calcium carbonate (CaCO3). Seventy-two palladium-silver cast copings were fabricated and divided into 6 groups: Temp Bond interim cement (TB); zinc phosphate cement (ZP); Rely X ARC resin cement (RX); pure COP (COP); COP + 10% wt% CaCO3 filler (COP 10); and COP + 50% wt% CaCO3 filler (COP 50). After cementation, the specimens were stored in distilled water at 37°C for 24 hours and subjected to removal force tests in a universal testing machine (5 kN; 0.5 mm/min). Statistical analyses were performed with the Kruskal-Wallis and Student-Newman-Keuls tests (α=.05). The median values of casting retention (N) were as follows: TB=57.20 ±10.4; ZP=343.56 ±50.3; RX=40.07 ±9.7; COP=258.98 ±41.4; COP 10=466.57 ±79.3; and COP 50=209.63 ±31.4. The Kruskal-Wallis test showed significant differences among the groups (P<.01). TB and RX had the lowest mean retention values; COP, COP 10, and COP 50 were equal to ZP, and COP 10 had the highest retention. The casting retention on implant-abutments provided by COP was similar to that of copings cemented with zinc phosphate and may be influenced by the addition of calcium carbonate.

The effect of different root canal sealers on the bond strength of titanium ParaPosts luted with two cements

PurposeThis study evaluated the effect of different root canal sealers (eugenol- and noneugenol-based) on the bond strength of prefabricated titanium ParaPosts luted with either zinc phosphate or resin cements. Materials and methodsOne hundred and sixty-eight single rooted teeth were included in this study. Teeth were distributed into seven groups (24 teeth each) according to type of root canal sealer used. Root canals were prepared and obturated with gutta percha and using one of the seven root canal sealers: AH26, Endoseal, Topseal, Sealapex, EndoREZ, Endofil, or Tubli-seal. Prefabricated titanium ParaPosts were luted with either zinc phosphate or RelyX ARC resin cements. The required force for the dislodgment of posts from their prepared spaces was recorded using a universal testing machine. Data were statistically analyzed using one- and two-way ANOVA, Tukey post hoc and the Student’s t-test. ResultsWithin the resin cement groups, the Endofil and Tubli-seal (eugenol-based sealers) groups had significantly reduced bond strength compared with other groups (P<0.05). Within the zinc phosphate cement groups, there were no significant differences between the post retention means (P>0.05). Comparing the two cements, there were significant differences within the Sealapex, Endofil, and Tubli-seal groups (P<0.05). ConclusionEndofil and Tubli-seal (eugenol-based) reduced the bond strength of prefabricated ParaPosts luted with RelyX ARC resin cement. The type of sealer used had less effect on the retention of posts that were luted with zinc phosphate cement than those luted with resin cement.

Does an intracanal composite anchorage replace posts?

This study aims to assess the effectiveness of an intracanal composite anchorage to replace conventionally cemented titanium or bonded glass fibre posts. Post space preparation was performed up to depths of 6mm (groups 1 and 2) and 3mm (group 3) in root filled mandibular premolars. In group 1, titanium posts were cemented with zinc phosphate cement. Glass fibre posts were adhesively cemented in group 2 using a dual-cure composite resin. In group 3, intracanal anchorage was solely performed with a dual-cure composite. All teeth were restored with standardised direct composite crowns without a ferrule. After thermo-mechanical loading, static load was applied until failure. Fracture patterns were assessed, and a microscopic analysis was performed to analyse the occurrence of additional cracks. Group 2 revealed a significantly higher median fracture value (408N) than groups 1 and 3, while no difference was detected between group 1 (290N) and group 3 (234N) (p = .1417). In group 3, the more favourable fracture patterns were observed. However, the majority of teeth within this fracture category revealed additional minor cracks of the root. Within the limitations of this study, adhesive intracanal anchorage to a depth of 3mm with resin composite only has the same fracture resistance as titanium posts conventionally cemented to a depth of 6mm. Even teeth with repairable main fractures exhibited additional dentinal cracks on the root. Additional dentinal root cracks in the teeth with repairable main fractures may considerably impair their longevity.

Comparing the Effect of a Resin Based Sealer on Crown Retention for Three Types of Cements: An In Vitro Study

To determine the effect of resin based sealer on retention of casting cemented with three different luting agents. 55 extracted molar teeth were prepared with a flat occlusal surface, 20° taper and 4mm axial height. The axial surface of each specimen was determined. The specimen were then distributed into five groups based on decreasing surface area, so each cementation group contained 11 specimens with similar mean axial surface area. A two-step, single bottle universal adhesive system (One-Step-Resinomer, Bisco) was used to seal dentin after the tooth preparation. Sealer was not used on the control specimens except for the modified-resin cement (Resinomer, Bisco) specimens that required use of adhesive with cementation. Using ceramometal (Wirobond(®), BEGO), a casting was produced for each specimen and cemented with either zinc phosphate (Harvard), glass ionomer (Vivaglass) or modified resin cement (Resinomer) with single bottle adhesive. All the castings were cemented with a force of 20kg. Castings were thermal cycled at 5 and 55°C for 2,500 cycles and were then removed along the path of insertion using a universal testing machine at 0.5mm/min. A single-factor ANOVA was used with a=0.05. The nature of failure was also recorded. The mean stress removal for non sealed zinc phosphate, sealed zinc phosphate, non sealed glass ionomer, sealed glass ionomer and modified resin cement was found to be 3.56, 1.92, 2.40, 4.26, 6.95MPa respectively. Zinc phosphate cement remained principally on the castings when the tooth surface was treated with the sealer and was found on both the tooth and the casting when the sealer was not used. Fracture of root before dislodgement was seen in 9 of 11 specimens with modified resin cement. Resin sealer decreases the retention of the castings when used with zinc phosphate and increases it when used with glass ionomer cement. The highest mean dislodgement force was measured with modified resin cement.

Prospective Evaluation of Zirconia Posterior Fixed Partial Dentures: 7-Year Clinical Results

The clinical performance of three- and four-unit fixed partial dentures (FPDs) with frameworks made of yttria partially stabilized zirconia was determined after a mean observational period of 84 months. Seventy-five patients were treated with 99 posterior FPDs. Fifty-one specimens were veneered with an experimental ceramic suitable for titanium and zirconia frameworks; 48 restorations were veneered with a commercially available low-fusing ceramic optimized for zirconia frameworks. All restorations were luted with zinc-phosphate cement. Statistical analysis was performed according to Kaplan-Meier; potential risk factors were analyzed using the Cox regression analysis. Nineteen restorations failed completely: 12 due to technical complications, 6 due to biologic complications, and 1 for unknown reasons. The overall survival rate after 84 months was 83.4%. Thirty-two events required clinical intervention for restoration maintenance, resulting in a time-dependent success rate of 57.9% after 84 months. Nineteen dropouts occurred during the follow-up time. None of the evaluated factors showed an association with survival or success of the restorations. After a mean observational period of 7 years, the survival and success rates of zirconia-based posterior FPDs were inferior to those published for metal-ceramic FPDs. The majority of failures were caused by technical complications (material fractures). The main reasons for clinical intervention to maintain function were fractures of the veneering ceramic and decementations.

Effect of types of luting agent on push-out bond strength of zirconium oxide posts

ObjectiveThe aim of this study was to investigate the effect of different luting agents on the bond strength of zirconium oxide posts in root canals after artificial ageing. Material and methodsThirty single-rooted extracted teeth were collected. Post spaces were prepared. Custom milled zirconium oxide posts (Cercon, Degudent) were fabricated. Specimens were divided into 3 groups (n=10), according to the luting agents used: group RA, conventional resin luting agent (RelyX ARC); group RU, self-adhesive resin luting agent (RelyX Unicem); and group Z, zinc phosphate luting agent (DeTrey). Specimens were subjected to thermocycling and water storage at 37°C. Specimens were horizontally sectioned into three sections and subjected to a push-out test with 0.5mm/min crosshead speed. The failure mode was assessed by scanning electron microscopy. Data were analysed by using 2-way ANOVA. ResultsThe following bond strength values were obtained: group RA – 8.89MPa, group RU – 10.30MPa and group Z – 9.31MPa. There was no significant difference in bond strength among the groups (P=0.500). Adhesive failure mode at the cement/post bonded interface was seen in 100%, 66.67% and 83.3% of examined sections in groups RA, RU and Z, respectively. There was no significant difference in bond strength among different root regions (P=0.367). ConclusionThe type of luting agent had no significant effect on the push-out bond strength of zirconium oxide posts after artificial ageing. Clinical significanceConventional luting agents, such as zinc phosphate cement, seem to provide comparable retention to resin luting agents for cementing custom milled zirconium oxide posts.

The Effect of Eugenol-Free Temporary Cement's Remnants on Retention of Full Metal Crowns: Comparative Study

The aim of this study was to evaluate the effects of eugenol-free temporary cement's remnants on the retentive strength of full metal crowns luted via zinc phosphate and resin cement (Maxcem) to the tooth structure. Forty complete standardized Ni-Cr crowns in four groups were cemented by two types of permanent cements: zinc phosphate cement and resin cement (Maxcem). In the two groups before permanent cementation of crowns, temporary acrylic crowns were cemented by eugenol-free temporary cement. Crowns' retention was evaluated by Universal testing machine. All data were analyzed by means of one-way ANOVA test in SPSS software version 11.5 (α=0.05). There was no significant difference in groups with prior using eugenol-free temporary cement and groups with just using two permanents cement (p-value≥0.05). The application of temporary cement before permanent cementation of full metal crowns does not have any adverse effect on retention of full metal crowns, when temporary cements are removed properly.

Comparison of the retention of the full veneer casted gold crowns with varying convergence angle, crown length and dental cements

Purpose: The aim of this research was to establish the effect and variation in differing convergence angle and length of abutment on the retention of full veneer casted gold crown. Materials and methods: Two different length,5 mm and 10 mm in height with convergence angles of 5, 10, 15 and 25 degrees crowns were fabricated. Cementation was done using cements; zinc phosphate cement (Fleck's zinc phosphate cement), resin-modified glass ionomer cement (Vitremer) and resin cement (Panavia 21). These were tested for tensile force at the point of separation by using Instron Universal Testing Machine. Statistical analysis was done by SAS 6.04 package. Results: In all cements the mean retention decreased with significant difference on increase of convergence angle (P<.05). Increase in every 5 degree-convergence angel the retention rate decreased with resin-modified glass ionomer cement of 15.9% and resin cement of 14.8%. With zinc phosphate cement, there was largest decreasing rate of mean retention of 25.5% between convergence angles from 5 degree to 10 degree. When the crown length increased from 5 mm to 10 mm, the retention increased with the significant difference in the same convergence angle and in all types of cement used (P<.05). Conclusion: The retention was strongly dependent on geometric factors of abutment. Much care is required in choosing cements for an optimal retention in abutments with different convergence angles and crown lengths. (J Korean Acad Prosthodont 2013;51:99-106)