Excavations at the Gebel Ramlah cemetery, in Upper Egypt’s Western Desert, have provided numerous data concerning mortuary practices of the local Final Neolithic period populace. Previous articles have chronicled treatment of disturbed... more
Excavations at the Gebel Ramlah cemetery, in Upper Egypt’s Western Desert, have provided numerous data concerning mortuary practices of the local Final Neolithic period populace. Previous articles have chronicled treatment of disturbed inhumations, in which great care had been taken to recover and rebury all grave goods and skeletal elements including, most notably, dental remains. In several cases, the Neolithic gravediggers apparently went so far as to reinsert, or to in other ways reincorporate, teeth that had fallen from their alveoli during handling. This report describes and interprets a new find, i.e., an anatomically accurate, life-size shell carving of a human incisor, that provides additional insight into the apparent importance of teeth to these desert people.
Using a sample of dental students (N=373) from four Canadian dental schools, this longitudinal study determined whether the new Canadian Dental Association (CDA) structured interview was a predictor of clinical and academic performance.... more
Using a sample of dental students (N=373) from four Canadian dental schools, this longitudinal study determined whether the new Canadian Dental Association (CDA) structured interview was a predictor of clinical and academic performance. The new interview predicted clinical performance in the third and fourth years of dental school, but not academic performance. The Canadian Dental Aptitude Test (DAT) continued to predict first- and second-year academic performance, but not clinical performance in the senior years. A personality factor, "Conscientiousness," predicted clinical and academic performance to various degrees across the four years of dental school. A second personality factor, "Openness to Experience," predicted third-year academic performance. The results suggest that a combination of scores from the DAT, a valid measure of personality, and a well-designed structured interview will provide the best prediction of those applicants who will do well in both...
Background: Despite many advantages of lasers and reduction of the risk of surface bonding errors with newer self-etch systems, they have not been thoroughly researched. This study was done to evaluate the effect of Er:YAG laser cavity... more
Background: Despite many advantages of lasers and reduction of the risk of surface bonding errors with newer self-etch systems, they have not been thoroughly researched. This study was done to evaluate the effect of Er:YAG laser cavity preparation on the microtensile bond strength of 2-hydroxyethyl methacrylate (HEMA)-rich and HEMA-free one-step self-etch adhesive systems. Materials and Methods: In this in vitro study, eighty freshly extracted human premolars were collected. Cavities were prepared in 40 teeth with carbide bur (Group 1) and in other 40 teeth with Er:YAG LASER (490 mJ and 15 Hz) (Group 2). Subgroups of twenty teeth each were made according to the adhesive systems used. After placement of restoration, the mean values of the bond strength were calculated using universal testing machine. Data were then tabulated and analyzed using descriptive statistics (Significant at P < 0.05). Results: The overall microtensile bonding strength was higher when the cavities were prep...
The corrosion resistance of AISI 304 stainless steel (AISI 304 SS) and manganese stainless steel (low-nickel SS) brackets in artificial saliva was investigated. The cytotoxic effects of their corrosion products on L929 cell culture were... more
The corrosion resistance of AISI 304 stainless steel (AISI 304 SS) and manganese stainless steel (low-nickel SS) brackets in artificial saliva was investigated. The cytotoxic effects of their corrosion products on L929 cell culture were compared by two assays, crystal violet, to evaluate cell viability, and MTT (3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide), for cell metabolism and proliferation. The atomic absorption spectroscopic analysis of the corrosion products demonstrated that nickel and manganese ion concentrations were higher for the AISI 304 SS-bracket immersion solution as compared with the low-nickel SS brackets. Scanning electron microscopy and energy-dispersive spectroscopy demonstrated less corrosion resistance for the AISI 304 SS brackets. Although none of the bracket extracts altered L929 cell viability or morphology, the AISI 304 SS-bracket extracts decreased cellular metabolism slightly. The results indicated that the low-nickel SS presents better i...
Background: Friction is usually encountered during sliding technique for orthodontic space closure. This study aims to investigate the effect of fluoride on frictional resistance between stainless steel orthodontic brackets and steel and... more
Background: Friction is usually encountered during sliding technique for orthodontic space closure. This study aims to investigate the effect of fluoride on frictional resistance between stainless steel orthodontic brackets and steel and NiTi arch wires. Materials and Methods: A total of 144 standard 022 stainless steel brackets were used in this experimental study. 0.016 and 0.019 × 0.025 inch steel and NiTi arch wires were tested. The frictional resistance between wires and brackets immersed in the following three solutions were measured: Sultan fluoride gel containing 1.23% acidulated phosphate fluoride at pH 3.5 for 4 minutes, aquafresh mouth wash containing 0.05% sodium fluoride at pH of 5.1 for 1 minute twice a day for 8 weeks and physiologic serum (pH=7) as the control group. Static and dynamic frictional forces were measured using Testometric machine. Surface topography of wires and brackets was qualitatively assessed using electron microscopy. Three-way and two-way variance...
Aim and Objectives: The aim of the present in-vitro study was to evaluate and compare the effect of five commercially available mouthrinses i.e. Listerine, Benzydamine, Rexidine, Proflo, Hiora on the microhardness of the hybrid composite... more
Aim and Objectives: The aim of the present in-vitro study was to evaluate and compare the effect of five commercially available mouthrinses i.e. Listerine, Benzydamine, Rexidine, Proflo, Hiora on the microhardness of the hybrid composite restorative material. Materials and Method: Fifty specimens were prepared withHybrid Composite Restorative Material (Te-Econom Plus) and immersed in Saleve (artificial saliva; supplied by the manufacturer) for 24hr. The baseline microhardness of specimens was recorded using Vicker's microhardness tester.The pH of mouthrinses was recorded with digital pH meter. All 50 specimens were divided into five groups of 10 samples each and immersed into20 ml of-Group I-Listerine (alcohol based) mouthrinse, Group II-Benzydamine (HCl based) mouthrinse,Group III-Rexidin (Chlorhex based) mouthrinse, Group IV-Proflo (fluoride containing) mouthrinse, and Group V-Hiora (alcohol free, herbal) mouthrinse and incubated for 24hr at 37ºC. After immersion the microhardness values of the specimens were recorded again and the data was tabulated for statistical analysis. Kruskal–Wallis test was used for inter group comparison followed by pairwise comparison of groups using Mann–Whitney U test. Results: All mouthrinses tested showed decreased microhardness of the Te-Econom Plus (hybrid composite restorative material) (P<0.001). Group I-(Listerine) showed highest reduction while Group II-(Benzydamine) showed the lowest reduction in the microhardnessof the hybrid composite restorative material respectively. Conclusion: All the five groups decreased the microhardness of the Hybrid Composite Restorative Material. The highest reduction in microhardness was found in alcohol-containing mouthrinse (Listerine).
Amelogenin-mineral interactions were investigated using an in vitro binding approach. Rat incisor enamel matrix proteins (mainly amelogenins) were dissolved in synthetic enamel fluid and allowed to equilibrate with deproteinised... more
Amelogenin-mineral interactions were investigated using an in vitro binding approach. Rat incisor enamel matrix proteins (mainly amelogenins) were dissolved in synthetic enamel fluid and allowed to equilibrate with deproteinised developing enamel crystals. The results showed that amlogenin proteins of 21, 23, 24, 26 and 27-kDa (corresponding to nascent and partially degraded amelogenins) were associated with the crystals whilst the lower Mr amelogenins (&lt; 21 KDa) remained free in the synthetic enamel fluid. These data suggest the nascent and partially degraded amelogenins may interact with developing enamel crystals and could influence their growth. Albumin-mineral interactions were investigated by extracting developing rat incisor enamel with synthetic enamel fluid. Insoluble material (including the enamel crystals) was then further extracted with 0.1 M phosphate buffer (pH 7.4) to desorb any mineral bound proteins. Western blotting using anti-albumin antibodies showed that almost all of the albumin from the secretory stage enamel and a significant proportion of the albumin present in early transition stage was extractable in the synthetic enamel fluid. However, synthetic enamel fluid did not extract albumin from late transition or maturation stage tissue, which could only be removed following further extraction with phosphate buffer. Albumin degradation was apparent during the transition and maturation stages, where it is degraded and ultimately removed. This binding pattern may be related to amelogenin degradation and removal during the transition stage, permitting albumin access to the previously obscured crystal surfaces. That the secretory stage matrix appears to &quot;protect&quot; secretory stage crystals from albumin may be an important consideration in the aetiology of enamel hypoplasias (i.e. incomplete crystal growth) and when using dissociative extraction procedures for the identification of mineral bound proteins.
Objective: The objective of the study was to assess the management of dental laboratory as it significantly affects effective handling of dental problems among dental patients visiting Dental Hospitals/Centres and consequently for... more
Objective: The objective of the study was to assess the management of dental laboratory as it significantly affects effective handling of dental problems among dental patients visiting Dental Hospitals/Centres and consequently for effective dental healthcare delivery system in Lagos State as a case study. Methodology: One hundred (100) dental professionals working in the selected twenty (20) dental hospital/centres across the study area were selected surveyed through a purposive sampling technique. The research instruments used for study were self-opinionated questionnaires and Strength, Weakness, Opportunities and Threat SWOT analysis. Finding: The results showed that state of the laboratories need to be improved in order to meet current global standards of digital state of equipments, then management of the laboratory with the perception of the staff influence the quality of dental care services given to the patients. The SWOT analysis indicated that opportunities within the profession is the adequacy of training and professionalism, while danger of quack workers, obsolete equipment, erratic power supply to run the equipment and lack of government enabling environment are threat and weakness that affect the dental laboratory activities. The study concluded that state of dental laboratory still need more improvement with the use of modern and digital equipments, and the workers re-training are the strengths and opportunities .Therefore, there is need for workshop, conferences and to educate the professional on the latest equipment in the markets on a global level. Then, the Government should embark on infrastructural development of the existing governmental dental facilities and encourage the private ones.
The increasing prevalence of gastroesophageal reflux disease (GERD) in children and adults, and of “silent refluxers” in particular, increases the responsibility of dentists to be alert to this potentially severe condition when observing... more
The increasing prevalence of gastroesophageal reflux disease (GERD) in children and adults, and of “silent refluxers” in particular, increases the responsibility of dentists to be alert to this potentially severe condition when observing unexplained instances of tooth erosion. Although gastroesophageal reflux is a normal physiologic occurrence, excessive gastric and duodenal regurgitation combined with a decrease in normal protective mechanisms, including an adequate production of saliva, may result in many esophageal and extraesophageal adverse conditions. Sleep-related GERD is particularly insidious as the supine position enhances the proximal migration of gastric contents, and normal saliva production is much reduced. Gastric acid will displace saliva easily from tooth surfaces, and proteolytic pepsin will remove protective dental pellicle. Though increasing evidence of associations between GERD and tooth erosion has been shown in both animal and human studies, relatively few cli...
In situ caries models serve purposes other than just being a simpler way to obtain data than running a clinical trial. However, variation in information obtained not only among individuals but also, in particular, depending on different... more
In situ caries models serve purposes other than just being a simpler way to obtain data than running a clinical trial. However, variation in information obtained not only among individuals but also, in particular, depending on different locations of the models within the oral cavity have so far been given little attention. In the present review, the aim has been to characterize the different designs of in situ caries models and to describe some important factors which may vary within the oral cavity and thus influence the outcome of the way the different in situ models are used. Advantages and disadvantages of in vivo models vs. in situ models are discussed. In the latter case, the distinction is made between dental appliance models and so-called "single tooth" models. The review concludes that in situ models differ distinctly with regard to their "biological potential". Because of regional differences in salivary film velocity, pH, and composition of the microfl...
Previous studies suggest that salivary and pulp-derived host enzymes, matrix metalloproteinases (MMPs), may be involved in dentin caries pathogenesis. To study the inhibition of acid-activated human salivary MMPs by non-antimicrobial... more
Previous studies suggest that salivary and pulp-derived host enzymes, matrix metalloproteinases (MMPs), may be involved in dentin caries pathogenesis. To study the inhibition of acid-activated human salivary MMPs by non-antimicrobial chemically modified tetracyclines (CMTs), we used a functional activity assay with 125I-labeled gelatin as a substrate. To address the role of MMPs in the progression of fissure caries in vivo, we administered the MMP inhibitors CMT-3 and zoledronate to young rats per os for 7 weeks, 5 days a week. Caries lesions were visualized by Schiff reagent in sagittally sectioned mandibular molars. Marked reduction in gelatinolytic activity of human salivary MMPs was observed with CMT-3. CMT-3 and zoledronate, both alone and in combination, also reduced dentin caries progression in the rats. These results suggest that MMPs have an important role in dentin caries pathogenesis, and that MMP inhibitors may prove to be useful in the prevention of caries progression.
Objective: This review was performed to answer the controversial clinical situation of post endodontic restoration of severely mutilated teeth with a high degree of evidence. The review helps evaluate the type of post (custom made cast... more
Objective: This review was performed to answer the controversial clinical situation of post endodontic restoration of severely mutilated teeth with a high degree of evidence. The review helps evaluate the type of post (custom made cast post) that demonstrates superior clinical performance in endodontically treated teeth. Data Sources: Electronic databases (MEDLINE, CENTRAL, SCIENCE DIRECT, GOOGLE SCHOLAR AND LILAC) were screened upto April 2021. Only randomised controlled trials with at least a follow up of one year were included in this review.
Dental education on specific knowledge and intervention approaches for working with people living on welfare is crucial to the therapeutic success of the relationships dental professionals establish with this clientele. Despite growing... more
Dental education on specific knowledge and intervention approaches for working with people living on welfare is crucial to the therapeutic success of the relationships dental professionals establish with this clientele. Despite growing attention to the importance of cultural competence and communication skills training in dentistry, very few initiatives have been documented in relation to serving low-income populations. Following discussions at a 2006 Montreal-based colloquium on access to dental care, academics, dental association administrators, and public health agency and antipoverty coalition representatives began collaborating to develop innovative pedagogy designed to increase providers' competence in interacting with their underprivileged patients. The group's first round of workshops (November 2006-October 2007) resulted in the creation of an original video-based tool containing testimonies from six individuals living currently or formerly on welfare. The videotaped...
Many systemic diseases affect oral health. The aim of this research was to conduct a systematic review on the association between dental erosion (DE) and gastroesophageal reflux disease (GERD) and the effect of saliva's flow rate,... more
Many systemic diseases affect oral health. The aim of this research was to conduct a systematic review on the association between dental erosion (DE) and gastroesophageal reflux disease (GERD) and the effect of saliva's flow rate, buffering capacity and oral microbial changes caused by GERD. All descriptive, analytical studies up to December 2011 that have relevant objectives, proper sampling method and sufficient results were included by searching PubMed and Scopus electronic data bases. Fifteen studies were selected according to our inclusion criteria (10 in adult and 5 in children population). There was a strong association between DE and GERD in the adult population, and the relationship in the children population was found to be of less importance. Early diagnosis and treatment of refluxed acid in both age groups through lifestyle changes and medications can prevent further damage and tooth loss.
Background: The long term management of miniplate fixation osteosynthesis remains debatable and controversial with few authors advocating routine removal of the miniplates after 3-6 months of placement, while others recommend retention of... more
Background: The long term management of miniplate fixation osteosynthesis remains debatable and controversial with few authors advocating routine removal of the miniplates after 3-6 months of placement, while others recommend retention of the miniplates unless their removal is clinically indicated. Objective: The aim was to study the incidence, indications, time gap, role of metallic composition and site of removal of miniplates in operated cases of maxillofacial region over a one-year period. Materials and Methods: Patients undergoing removal of miniplates over a one year period were studied and evaluated regarding the number of miniplates removed, time gap present between fixation and removal of miniplates, indications for removal, metallic composition of miniplates removed, sites of removal and complications. Correlations between indications for miniplate removal based upon time gap, metallic composition, age of patients undergoing plate removal and number of miniplates present were determined using Chi-square test. Correlation between metallic composition of miniplate and time gap was also determined using Chi-square test Results: The miniplates were removed in 31 patients (26 males and 5 females). Most common indication for removal was infection (45%). Forty-five percent of the patients underwent miniplate removal within 1 year of placement. The correlation between indications for miniplate removal and time gap was found to be statistically significant (P = 0.04). Conclusion: Most of the hardware removal is performed subsequent to complications associated with hardware and local factors . There is no significant association between the composition of the hardware and pate removal . However there is a significant association between the time gap and indication for plate.Miniplate removal should be performed when hardware is causing various complications and physical symptoms. Infection, miniplate exposure, pain, palpability or any other morbidity that appears after bony union should be treated by miniplate removal.
Introduction: The success of endodontic treatment is complete obturation of the root canal system up to the cementodentinal junction. Obturation of the root canal is usually done with gutta-percha along with a root canal sealer. Sealers... more
Introduction: The success of endodontic treatment is complete obturation of the root canal system up to the cementodentinal junction. Obturation of the root canal is usually done with gutta-percha along with a root canal sealer. Sealers are used as binding agents, and they lubricant and aid in sealing of gutta-percha. The hermetic sealing of the root canal by means of a three dimensional obturation of the pulp space constitutes the key factor for successful endodontic therapy. Aim and objective: The aim of the present study was to evaluate and compare the apical sealing ability of three root canal sealers using dye penetration method.
Many studies have investigated the relationship between periodontal and cardiovascular diseases but their results are heterogeneous. Meta-analyses were conducted to examine the association between exposure to periodontitis and... more
Many studies have investigated the relationship between periodontal and cardiovascular diseases but their results are heterogeneous. Meta-analyses were conducted to examine the association between exposure to periodontitis and cardiovascular diseases. Studies published between 1989 and 2007 were retrieved from seven databases. The included articles reported the results from observational studies (cohort, cross-sectional and case-control studies) and assessed the link between periodontal exposure and cardiovascular diseases as confirmed by one of the following criteria: diagnosed coronary artery disease, angina pectoris, acute myocardial infarction, mortality caused by cardiac pathology. The study characteristics were abstracted by independent researchers following a standardised protocol. The MOOSE guidelines for meta-analysis of observational studies were followed. From 215 epidemiological studies, 47 were observational, of which 29 articles could be combined by the meta-analysis m...
ABSTRACT : The root canal system is an arborizational, anastomotic, byzanthine, labyrinthine complexity, morphologically comparable to a mosaic. While primary canals exist, the tributaries, accessory branches and lumina of dentinal... more
ABSTRACT : The root canal system is an arborizational, anastomotic, byzanthine, labyrinthine complexity, morphologically comparable to a mosaic. While primary canals exist, the tributaries, accessory branches and lumina of dentinal tubules harbour extensive tissue and microflora which if left untreated remains vector for persistent and refractory pathology. Therefore root canal shaping and cleaning is of utmost importance in the success of root canal treatment. Number of systems are available for effective shaping accounting from hand files to nickel titanium rotary files to the new single file concept “WAVE ONE” KEYWORDS : Wave One, Reciprocating Motion, Nickel Titanium, Reverse Balanced Force Technique, vCJD | Dr VINEET VINAYAK| Dr VINEET VINAYAK|dr VINEET vinayak
Avulsion of permanent teeth is the most serious of all dental injuries. The prognosis depends on the measures taken at the place of accident or the time immediately after the avulsion. Replantation is the treatment of choice, but cannot... more
Avulsion of permanent teeth is the most serious of all dental injuries. The prognosis depends on the measures taken at the place of accident or the time immediately after the avulsion. Replantation is the treatment of choice, but cannot always be carried out ...
The HIV/AIDS pandemic marks a severe development crisis in Africa, which remains by far the worst affected region in the world. Forty-two million people now live with HIV/AIDS of which 29.4 million (70.0%) are from sub-Saharan Africa.... more
The HIV/AIDS pandemic marks a severe development crisis in Africa, which remains by far the worst affected region in the world. Forty-two million people now live with HIV/AIDS of which 29.4 million (70.0%) are from sub-Saharan Africa. Approximately 5 million new infections occurred in 2002 and 3.5 million (70.0%) of these were also from sub-Saharan Africa. The estimated number of children orphaned by AIDS living in the region is 11 million. In 2002, the epidemic claimed about 2.4 million lives in Africa, more than 70% of the 3.1 million deaths worldwide. Average life expectancy in sub-Saharan Africa is now 47 years, when it would have been 62 years without AIDS. HIV/AIDS stigma is still a major problem despite the extensive spread of the epidemic. A complex interaction of material, social, cultural and behavioural factors shape the nature, process and outcome of the epidemic in Africa. However, too many partners and unprotected sex appear to be at the core of the problem, Even if ex...
Introduction: The study was undertaken to compare two indirect bonding methods, one method used a light cured adhesive system and clear vacuum formed transfer trays and a second method used a chemical cure adhesive system and putty... more
Introduction: The study was undertaken to compare two indirect bonding methods, one method used a light cured adhesive system and clear vacuum formed transfer trays and a second method used a chemical cure adhesive system and putty transfer trays Materials and Methods: 191 bondings provided a data base of bond failures for two indirect bonding methods. The initial bond failure rates were compared using Fisher's Exact Test. The long term bond failure rates were compared using actuarial life tables and a Mantel-Haenzel comparison. Results: In initial bond failure the light cured method had a 9% failure rate compared to the chemical cured methods 0.7% failure rate. Long term the light cured method had a 0% failure rate while the chemical cured method had a 9% failure rate. Conclusion: The initial bond was less likely to fail with the chemically cured method but long term the light cured method was had fewer bond failures. Introduction When bonding fixed orthodontic appliances to teeth orthodontists have the choice of bonding indirectly or directly. Indirect bonding involves positioning the brackets on models of the teeth and then transferring the brackets to the patient's mouth to be bonded. This allows for determining the position of the bracket in the lab away from oral sources of contamination. It also allows for the evaluation of bracket position without the use of a mirror and from view points that would be difficult or impossible if positioning brackets directly in the mouth [1]. Once the bracket position is satisfactory a transfer tray is fabricated and the brackets can then be transferred to the patient's mouth with all of the brackets maintaining the chosen position. Conversely direct bonding involves positioning the brackets in the mouth and then bonding the bracket in place. This allows more time for the adhesive system used to bond the bracket to become contaminated [2]. Also, due to confined environment on the mouth often times in is difficult to fully visualize the bracket position. A large factor in initial and long term bond failure is contamination of the bonding site by saliva, blood, and or water. This contamination can occur after etching or after the placement of the primer/bonding agent. In the light cured indirect bonding method being studied brackets are placed in the mouth in groups of 5-12 and then bonded in place individually. The light cured method recommends a total of 10 seconds of curing per tooth in two separate 5 second intervals. The chemically cured indirect bonding method being studied places the brackets in the mouth in groups of 5-12 which are bonded simultaneously to the teeth. The chemical cure requires a 4 minute set time. The difference in timing and manner of curing allow for separate paths of contamination with no clear advantage to either method. Bond failures can represent a significant increase in treatment time. In 2007, a study by Haeger et al. [3] found an average increase of 1.21 months of treatment time per bond failure. Typical treatment times range from 16-24 months with each bond failure representing a 5-8% potential increase in treatment time. Longer treatment time increases the risk of root resorption and carious white spot lesions. Root resorption decreases the amount of tooth structure supported by bone and compromises the long term health of the tooth. White spot lesions are precursors to dental cavities and also present an aesthetic blemish on the tooth that is permanent. By determining if certain indirect bonding methods provide for decreased bond failure
Globalization is a broad term referring to the increasing connectivity, integration, and interdependence of economies, societies, technologies, cultures, and political and ecological spheres across the world. This position paper was... more
Globalization is a broad term referring to the increasing connectivity, integration, and interdependence of economies, societies, technologies, cultures, and political and ecological spheres across the world. This position paper was developed by a working group of the 2007 American Dental Education Association (ADEA) Leadership Institute. The authors explore the effect that globalization has had on dentistry and dental education to date and hypothesize what dental education could look like in the years ahead. While the paper is written from a North American perspective, some of the authors bring international expertise and experience to the topic of global dental education in a flat world. Specific issues and barriers addressed in this position paper include variations in accreditation and licensure requirements in dental education throughout the world; the historical development of dental education models (odontology and stomatology) and the need for congruency of these models in t...
The purpose of this study was to compare the retention of circlet (E) clasps and back-action clasps against three abutment surface materials during long-term simulation of attachment and detachment. Forty-eight test models were... more
The purpose of this study was to compare the retention of circlet (E) clasps and back-action clasps against three abutment surface materials during long-term simulation of attachment and detachment. Forty-eight test models were constructed by placing premolars (natural abutments or metal dies) inside metal blocks to test different abutment retention surface materials (sound enamel, composite resin, and glass-ceramic; 16 each). The models were duplicated into investment models for construction of circlet (E) and back-action clasps. Removal and insertion cycling of clasps was carried out for 250, 500, 1000, 2000, 4000, 8000, and 16,000 cycles. The retention of each clasp was measured before cycling and after each interval. Data were analyzed using 1-way-ANOVA, 2-way-ANOVA, and Mann-Whitney U tests. No significant differences in retention of either clasp were found between the three abutment material surfaces; however, there was a significant decrease in retention force of the circlet (E) clasp between 1000 and 2000 cycles but not of the back-action clasp. (1) The back-action clasp maintains its retention force for a longer period than the circlet (E) clasp. (2) Composite resin contouring of teeth provided retention comparable to enamel and a ceramic material.