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Articles 991 - 1020 of 1252

Full-Text Articles in Orthodontics and Orthodontology

Patient Satisfaction And Effectiveness Of A New Resin Used To Bumper Orthodontic Brackets, Timothy B. Elison Aug 2002

Patient Satisfaction And Effectiveness Of A New Resin Used To Bumper Orthodontic Brackets, Timothy B. Elison

Loma Linda University Electronic Theses, Dissertations & Projects

Fear of pain is a key factor in discouraging patients from seeking orthodontic treatment, with many patients discontinuing treatment due to pain experienced in the early stages of treatment. Patients often complain of traumatized lips and buccal mucosa, which is usually caused by the brackets. Orthodontists try to minimize this pain and discomfort by using bumpering materials. Although wax is the most commonly used product, there are many bracket bumpering materials available.

The purpose of this study was to evaluate the clinical effectiveness and patient comfort/satisfaction of a new flowable resin, Ortho Shield, designed to protect the lips and …


Evaluation Of Alveolar And Soft Tissue Changes After Muscular Release Surgery In Patients Undergoing Fixed Orthodontic Therapy, Virginia Bernal Jun 2001

Evaluation Of Alveolar And Soft Tissue Changes After Muscular Release Surgery In Patients Undergoing Fixed Orthodontic Therapy, Virginia Bernal

Loma Linda University Electronic Theses, Dissertations & Projects

This study compared pre-treatment to post-treatment changes in patients undergoing fixed orthodontic therapy who have had muscular release surgery. The alveolar and soft tissue changes in the mandible of 128 subjects from a private practice in Northern Italy (74 females and 54 males) were analyzed. In addition, comparisons were made of changes related to age, gender, facial type, and movement of the lower incisor. Lateral cephalograms were analyzed before and after treatment for skeletal, esthetic, and dentoalveolar changes. Photographs were used to assess changes in the soft tissue of the lower anterior region at pretreatment (Tl) versus post-treatment (T2). The …


A Continued Investigation Of Craniofacial Growth In Infant Heart Transplant Recipients Receiving Cyclosporine, John Michael Cornali Jun 2001

A Continued Investigation Of Craniofacial Growth In Infant Heart Transplant Recipients Receiving Cyclosporine, John Michael Cornali

Loma Linda University Electronic Theses, Dissertations & Projects

Cyclosporine is an effective immunosuppressive drug that has found widespread application in organ transplantation. A couple of studies, however, have implicated cyclosporine as adversely affecting craniofacial growth in the pediatric population. The purpose of this follow-up study was to continue to evaluate the possible untoward effects of long-term use of cyclosporine on craniofacial growth in a group of infant heart transplantation recipients by re-evaluating as many subjects as possible from the original study and evaluating new subjects. A prospective group (N=29) of eighteen Caucasian subjects (7 female and 11 male, ages 6-15 years) and eleven Hispanic subjects (3 female and …


Fracture Properties Of Different Orthodontic Bonding Materials, Daryl Lynden Proctor Jun 2001

Fracture Properties Of Different Orthodontic Bonding Materials, Daryl Lynden Proctor

Loma Linda University Electronic Theses, Dissertations & Projects

Spontaneous debonding has proven a constant problem since the introduction of bonded orthodontic brackets in the early 1960's by Newman1.

Components in classic bond strength testing are the bracket, the adhesive, the adhesive curing method, the type of teeth used, and the test method. These tests lead to extensive and compounding variables that make it difficult to evaluate the performance of any of the components individually.

The purpose of this study was to compare several contemporary orthodontic bonding adhesives by testing the physical and mechanical characteristics of the adhesives alone. Material properties compared were sonic and tensile measurements …


Optimum Bonding Time Of Four Different Curing Lights, Nathan Don Cotten Jun 2001

Optimum Bonding Time Of Four Different Curing Lights, Nathan Don Cotten

Loma Linda University Electronic Theses, Dissertations & Projects

With the development of new high-intensity curing lights, the time required to bond orthodontic brackets is steadily decreasing. The objective of this study was to determine the optimum curing time for bonding orthodontic brackets using four different visible curing lights (Standard Optilux 501, High Intensity Optilux 501 with Turbo Tip, Virtuoso Plasma Arc, and ESPE LED light). This study also tested the new generation of light emitting diode (LED) lights to determine if they can be used for bonding orthodontic brackets. Three hundred freshly extracted bovine teeth were mounted in acrylic resin and divided into 20 groups of 15 teeth …


An In Vitro Study Of The Durability Of A Proprietary Decalcification Inhibiting Sealant, Michaela Camille Neagu Jun 2000

An In Vitro Study Of The Durability Of A Proprietary Decalcification Inhibiting Sealant, Michaela Camille Neagu

Loma Linda University Electronic Theses, Dissertations & Projects

Plaque accumulation, although undesirable, is prevalent in orthodontic patients with poor oral hygiene and is linked with enamel decalcification. A proposed product designed to seal the tooth around the orthodontic bracket was tested for its durability. It also was evaluated for its ability to seal the enamel.

We measured prepared areas of sixty bovine teeth that were divided equally into two groups: a control group, protected with light-cured Concise sealant, and a group treated with the test sealant, Odyssey, both by 3M Unitek. The teeth were thermocycled for 1000 cycles in alternating 5° C and 55° C waterbaths at 10-second …


A Comparison Of Four Curing Lights For Bonding Of Orthodontic Brackets, David Sy Nguyen Jun 2000

A Comparison Of Four Curing Lights For Bonding Of Orthodontic Brackets, David Sy Nguyen

Loma Linda University Electronic Theses, Dissertations & Projects

Light cured adhesives have gained more popularity since their introduction more than three decades ago. Photo-polymerization allows more thorough curing on demand and thus facilitates better control of bracket placement. With new technologies, recently developed curing lights promise even more improvement. These systems are not only more sophisticated, but also more sensitive to the types of resins and clinical application. Specific comparison studies of the new systems in the orthodontic bonding are lacking because most of curing lights are originally designed for general dentistry.

This study evaluated the in-vitro ability of four curing lights to polymerize the Transbond XT bonding …


An Evaluation Of The Short And Long Term Effects Of Quad Helix Expansion, Sonja F. Finnie Jun 2000

An Evaluation Of The Short And Long Term Effects Of Quad Helix Expansion, Sonja F. Finnie

Loma Linda University Electronic Theses, Dissertations & Projects

This study was conducted to examine, retrospectively, orthodontic and orthopedic changes resulting from quad helix expansion therapy in mixed and permanent dentition stages. Twenty-one subjects with an average age of 10.2 years who experienced an expansion of at least 3 mm with the quad helix appliance were selected for this study. The subjects were evaluated according to facial type and age for both short and long-term stability. Plaster dental casts and posteroanterior (frontal) radiographs were evaluated at the beginning of treatment (T1), at the completion of Phase 1 or full treatment (T2), and approximately two years following the completion of …


Failure Mode Of An Orthodontic Resin Alone And With Bonded Brackets, Marc Cody Dunn Jun 2000

Failure Mode Of An Orthodontic Resin Alone And With Bonded Brackets, Marc Cody Dunn

Loma Linda University Electronic Theses, Dissertations & Projects

Since the introduction of bonded orthodontic brackets in the early 1960's spontaneous debonding has been a constant nemesis. Most attempts to avoid this problem by orthodontic manufactures have focused on "bond strength" issue. Whether they chose to address the materials, the bracket base or both, the common method used to evaluate improvements entailed the use of just one testing apparatus: a static universal testing machine such as the Instron.

Metal, ceramic and plastic bonded brackets were tested with the traditional shear/peel method as well as a new high strain rate impact test. The resin itself was also evaluated for physical …


An Extension Of Euclidean Distance Matrix Analysis Applied To Craniofacial Growth Prediction, Mark K. Batesole Jun 2000

An Extension Of Euclidean Distance Matrix Analysis Applied To Craniofacial Growth Prediction, Mark K. Batesole

Loma Linda University Electronic Theses, Dissertations & Projects

This study is [sic] introduces a new extension of Euclidean Distance Matrix Analysis (EDMA) as applied to growth prediction analysis. Using EDMA eliminates the presupposition of a set growth pattern, which is introduced by traditional superimposition techniques. When EDMA is extended to analyze prediction methodologies, using a non-age-matched growth sample, some shortcomings become evident. These involve bootstrapping techniques, relative difference in growth, and absence of clinical, real world measure. To overcome these issues, a statistical approach using the Wilcoxen signed rank test, absolute difference in growth, and a new method to evaluate the error in a prediction methodology's landmark identification …


Post-Treatment Evaluation Of Isometric Function Of The Elevator Muscles, Margaret Barbara Kowalczyk Jun 2000

Post-Treatment Evaluation Of Isometric Function Of The Elevator Muscles, Margaret Barbara Kowalczyk

Loma Linda University Electronic Theses, Dissertations & Projects

This study mainly examined neuromuscular function, occlusal index, and centric relation-centric occlusion (CR-CO) discrepancy of 23 orthodontically treated patients. Phase I, craniofacial anomalous, and orthognathnic surgery cases were excluded from the study. Record taking was done in 2 sessions: (1) at the time of deband and (2) 3-4 months later. Records taken at each session included facial and intraoral photographs, impressions, CR wax bites, a facebow, and surface EMG (sEMG) recordings.

For the sEMG recordings, electrodes were placed on the upper hyoid, masseter, and anterior temporalis muscles. Subjects were asked to perform numerous tests; these included baseline, clenching to test …


Accuracy Of Zerobase™ Growth Prediction Of A Burlington Sample, Anitha Nair Mar 2000

Accuracy Of Zerobase™ Growth Prediction Of A Burlington Sample, Anitha Nair

Loma Linda University Electronic Theses, Dissertations & Projects

The accuracy of ZeroBase™ orthodontic software program was tested using a sample of 14 male and 14 female untreated subjects classified as skeletal Class II pattern by the Burlington growth center. Growth predictions were carried out by ZeroBaseTM from ages 6,9,12,14,16 in males and 6,9,12 and 14 in females. The mean computer predicted value was compared with the mean radiographic value to test the accuracy of the predictions. Predictions from age 14 were the most accurate (within one standard deviation), whereas the predictions from age 6 were the least accurate. In males, the accuracy of cranial base predictions was 73.3%, …


The Effect Of Mandibular First Molar Tip Back On Mandibular Incisor Long-Term Stability, Barton L. Soper Sep 1999

The Effect Of Mandibular First Molar Tip Back On Mandibular Incisor Long-Term Stability, Barton L. Soper

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to determine if mandibular first molar distal tip back during orthodontic treatment will result in improved long-term alignment of mandibular incisors. Our pre and posttreatment sample consisted of 57 Class I and Class II patients (40 female and 17 male). Incisor irregularity was recorded at T2 and T4 (average of 12.9 years postretention at T4). Molar tipback was evaluated T1 to T2 and T2 to T4. The sample was divided into 3 groups - molars tipped distally 1 degree or more during treatment, molars essentially not tipped, and molars tipped mesially 1 degree or …


Clinical Debonding Simulation Study Of One Metal And Two Ceramic Brackets, Hyunsup Shim Sep 1999

Clinical Debonding Simulation Study Of One Metal And Two Ceramic Brackets, Hyunsup Shim

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to compare two mechanical debonding methods on ceramic brackets (TP MXi and 3M Clarity) and a metal bracket (GAC OmniArch) with four different bonding materials (light-cured, one-step chemical-cured, two-step chemical-cured, and Fuji GIC) in clinical simulation, where the diametral force was applied on the handle of the pliers. The effectiveness of mechanical debonding technique was determined by evaluating the following variables: the amount of force required to debond the bracket, the amount of residual adhesive remaining on the enamel surface, the frequency of unexpected bracket failure, and the prevalence of visible enamel damage. The …


Diagnosis And Treatment Of Swallowing Dysfunctions : Semg Cognitive Training As An Adjunct To Conventional Therapy, Vicky T. Nguyen Jun 1999

Diagnosis And Treatment Of Swallowing Dysfunctions : Semg Cognitive Training As An Adjunct To Conventional Therapy, Vicky T. Nguyen

Loma Linda University Electronic Theses, Dissertations & Projects

This study compared surface electromyography (sEMG) cognitive training to conventional myofunctional therapy in controlling a swallowing dysfunction, commonly referred to as "tongue thrust". Nasal airway resistance (NAR) was assessed on every subject, to rule out mechanical obstruction that would prevent proper function. The scope of this investigation composed of evaluating baseline activity and dry swallowing patterns. Subjects were distributed to one of three treatment groups: sEMG cognitive training, conventional myofunctional therapy, and control, based on the degree of NAR (normal, mild, or moderate). Initial sEMG recordings were then taken on subjects that clinically demonstrated a tongue thrust habit to confirm …


The Validation Of An Existing Sleep Apnea Questionnaire And Its Application To Clinical Orthodontics, Jeffery C. Biggs Jun 1999

The Validation Of An Existing Sleep Apnea Questionnaire And Its Application To Clinical Orthodontics, Jeffery C. Biggs

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to validate a sleep apnea questionnaire from the Loma Linda University Sleep Disorders Center, and then to utilize the questionnaire in order to identify potential sleep apnea patients from a pre-orthodontic patient sample. Study patients were selected from the Loma Linda University Sleep Disorders Center and the Loma Linda University Orthodontics Clinic, both in Loma Linda, California, USA.

Methods: The study sample represented all of the patients initially examined from 1996 through 1998 who were age 8-15 years old at the time of the initial exam. Validation of the questionnaire was based on responses …


Evaluation Of The Effects Of Heat Treatment Using Orthotherm On Thermally Activated Archwires, Brent J. Hurst Jun 1999

Evaluation Of The Effects Of Heat Treatment Using Orthotherm On Thermally Activated Archwires, Brent J. Hurst

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate the effects of heat treatment on thermally activated nickel titanium archwires, and to determine the differences between wires from individual manufacturers. Thermally activated, nickel titanium wires were obtained from five different manufacturers in the 0.016 x 0.022 format. All wires were measured with a micrometer to determine their exact dimensions. Half of the wires were heat treated with the use of the Orthotherm Bending Art Programmer from Syrinx Medical Technologies (Berlin, Germany) while the other half served as a control. By passing an electrical current through the wires for a predetermined period …


A Comparison Of Bond Strength Between Three Glass Ionomer Cements Used For The Retention Of Orthodontic Bands, Bryan C. Johnson Sep 1998

A Comparison Of Bond Strength Between Three Glass Ionomer Cements Used For The Retention Of Orthodontic Bands, Bryan C. Johnson

Loma Linda University Electronic Theses, Dissertations & Projects

The study compared the retentive bond strength of Ketac-Cem with Ultra Bond-Lok and a 3M Experimental glass ionomer cement at 1 hour and 24 hours using laser and common light cure techniques. The sample consisted of one hundred twenty sound extracted human molars divided into 5 groups: Ketac-Cem (self-cure), Ultra Band-Lok (light-cure), Ultra Band-Lok (laser cure), 3M Experimental (light-cure) and 3M Experimental (laser cure). Stainless steel orthodontic bands with buccal and lingual cleats were cemented as per manufacturer's instructions for each of the test samples. The samples were placed in water until ready for testing. The shear bond strength of …


Establishing Norms For A Mexican Group Using Ricketts, Steiner And Arnett Analyses, Mauricio Gonzalez Balut Sep 1998

Establishing Norms For A Mexican Group Using Ricketts, Steiner And Arnett Analyses, Mauricio Gonzalez Balut

Loma Linda University Electronic Theses, Dissertations & Projects

Most existing cephalometric analyses are based on norms for the Caucasian population. Therefore, they cannot be properly applied for Mexican or Hispanic patients. Ethnic variations in the normal positions of the maxilla and mandible influence and alter the diagnosis and treatment plan for each of the different type of malocclusions. Previous studies have addressed the difference between the Caucasian norms and the Hispanic norms, this indicates the variety of their skeletal, dental and facial features.

It is the purpose of this study to establish specific cephalometric standards for the native Mexican group, using the Steiner and Ricketts analyses along with …


The Relationship Of The Incisive Canal To Maxillary Median Diastema, Jeffery S. Corbett Sep 1998

The Relationship Of The Incisive Canal To Maxillary Median Diastema, Jeffery S. Corbett

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to assess the relationship between the incisive canal and maxillary median diastema, and to identify an imaging method capable of documenting the geometry and dimensions of the incisive canal. The sample consisted of 59 dry skulls, 26 of which had a maxillary median diastema ranging in size from 0.1 mm to 2.8 mm (mean 1.0 mm, SD = 0.7 mm). Each skull had all of the permanent maxillary teeth present from first molar to first molar and lacked any apparent non-orthodontic condition that could have caused the diastema. Diastema width and canal diameter were …


A Comparison In Processing Of Alginate Orthodontic Impressions By Commercial Labs, Robert Agnetta Sep 1998

A Comparison In Processing Of Alginate Orthodontic Impressions By Commercial Labs, Robert Agnetta

Loma Linda University Electronic Theses, Dissertations & Projects

Many orthodontists use commercial orthodontic laboratories for the processing of their impressions including preparation of the impression for pouring, model retrieval, final trim, and labeling. It was studied, by way of random sample survey, what materials and methods were most commonly utilized in 100 offices of members of the American Association of Orthodontics. This survey data was analyzed and used to establish a protocol to study differences in dimensions of models made from impressions that were poured immediately, versus those that were stored and picked up at the office the same day they were taken, and those that were shipped …


A Pilot Study Testing A Proprietary Sealant For Plaque Reduction, Jennifer Rowland Jun 1998

A Pilot Study Testing A Proprietary Sealant For Plaque Reduction, Jennifer Rowland

Loma Linda University Electronic Theses, Dissertations & Projects

Enamel demineralization due to increased plaque accumulation is a well-recognized problem associated with fixed orthodontic appliances. The purpose of this study was to evaluate the efficacy of a proprietary product to be marketed by 3M Unitek for the reduction of plaque accumulation and thereby reduce enamel demineralization.

Sixty four bovine teeth were divided equally into an untreated control group and a group treated with the proprietary sealant product. Both groups were subsequently immersed in a Streptococcus mutans culture. Plaque deposits from each group were removed, suspended in trypticase soy broth, serially diluted, and plated on trypticase soy agar at 1, …


An In Vitro Study Of Plaque Deposition And Its Comparative Effect On Bond Strength, Debra L. Finch Cook Jun 1998

An In Vitro Study Of Plaque Deposition And Its Comparative Effect On Bond Strength, Debra L. Finch Cook

Loma Linda University Electronic Theses, Dissertations & Projects

Treatment with fixed orthodontic appliances can change the environment in the oral cavity by creating stagnant areas that facilitate bacterial colonization and substance retention. The purpose of this study was to examine in vitro plaque formation associated with bonded orthodontic appliances and how this could affect bonding strengths.

Ortho Concise and Transbond XT were the composite resin materials used in this study. Mandibular incisor metal brackets were bonded to bovine mandibular anterior teeth. Each composite resin was studied in two groups: plaque growth and without plaque growth, and their bond strengths were compared at time intervals of 3,45, and 180 …


A Cephalometric Study Of The Class Ii Correction Effects Of The Eureka Spring, Ernest L. Stromeyer Aug 1997

A Cephalometric Study Of The Class Ii Correction Effects Of The Eureka Spring, Ernest L. Stromeyer

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of the Eureka Spring appliance, was investigated on 37 consecutively treated, non compliant, bilateral Class II malocclusions, requiring at least 3 mm or more of additional molar correction. The mean pretreatment age of this sample was 13.9 years. All patients were treated by a single clinician utilizing the Eureka Spring. Lateral cephalographs were taken at start of orthodontic treatment (T1), at insertion of Eureka Springs (T2), and at removal of the Eureka Springs (T3). The average treatment interval between T2 and T3 was 4 months. Class II correction occurred almost entirely by dentoalveolar movement, 33% in the maxilla …


A Pilot Study On The Short Term Effects Of The Herbst Appliance On The Glenoid Fossa, David A. Bennion Aug 1997

A Pilot Study On The Short Term Effects Of The Herbst Appliance On The Glenoid Fossa, David A. Bennion

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this pilot study was to evaluate the initial effects of the Herbst appliance and determine through the use of common cephalometric radiographs that were optically enhanced and then digitally reproduced, if fossa migration is taking place. Fourteen, (6 male, 8 female), growing patients were treated by the same clinician for the correction of a Class II malocclusion using a modified Herbst appliance. Pretreatment (T1) standard lateral cephalometric radiographs and post Herbst treatment (TH) optically enhanced lateral cephalometric radiographs were taken. All radiographs were digitally captured and reproduced so 6 linear and 1 area …


An Investigation Of The Divine Proportion In Varying Facial Types, Gender And Age Groups, Chris A. Coleman Jun 1997

An Investigation Of The Divine Proportion In Varying Facial Types, Gender And Age Groups, Chris A. Coleman

Loma Linda University Electronic Theses, Dissertations & Projects

This retrospective study evaluated the 26 cephalometric measurements which comprise 13 ratios that were purposed by Robert M. Ricketts to be Divine Proportions. The hypothesis that was tested in this study was one that stated that these 13 ratios were not only Divine Proportions, but were constant in all facial types, in both genders and in all stages of growth. In an effort to test this hypothesis, cephalographs were chosen at random from the files of Dr. Ruel Bench, which are currently housed in the Ricketts Research Library at Loma Linda University. Each film tracing was reviewed for accuracy and …


A Study Of Craniofacial Growth In Infant Heart Transplant Recipients Receiving Cyclosporine, David G. Niles Jun 1997

A Study Of Craniofacial Growth In Infant Heart Transplant Recipients Receiving Cyclosporine, David G. Niles

Loma Linda University Electronic Theses, Dissertations & Projects

Cyclosporine is an effective immunosuppressive drug that has found widespread application in organ transplantation. However, a few studies have implicated cyclosporine as adversely affecting craniofacial growth in the pediatric population. The purpose of this study was to evaluate the possible untoward effects of cyclosporine long-term on craniofacial growth in a group of infant heart transplantation recipients. A prospective group (n=28) of eighteen Caucasian children (9 female and 9 male, ages 4-10 years) and ten Hispanic children (3 female and 7 male, ages 4-10 years) were evaluated. None of the subjects had undergone orthodontic therapy. All subjects had heart transplantation before …


A Comparative Study Of The Permanent Deformation Of Aesthetic Polymer Brackets, Samar Bou Assi Jun 1997

A Comparative Study Of The Permanent Deformation Of Aesthetic Polymer Brackets, Samar Bou Assi

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to Investigate and compare the plastic or permanent deformation of different commercially available aesthetic polymer brackets (American, Ormco, GAC and RMO). It also examined the effect of tying the bracket wings with a wire ligature as well as the effect of thermocycling on the permanent deformation of these brackets.

Seven brackets of each type were tested In each of the three following conditions; group 1; tied with a wire ligature and loaded, group 2; thermocycled and loaded, and group 3: loaded only, with a total of 84 brackets tested. Each bracket was bonded to …


The Relationship Of Tooth Size And Arch Form To Arch Depth, Harold C. Avila Jun 1997

The Relationship Of Tooth Size And Arch Form To Arch Depth, Harold C. Avila

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the relationship of arch form and tooth size to arch depth measurements of study models (Casts) and their respective lateral cephalometric radiographs (Radiographs) in a population of patients treated to an acceptable occlusion without extraction. One hundred and twenty casts were divided into three tooth size classes within each of four arch form categories. Results showed there was a statistically significant change in the arch depth measurement when tooth size was varied. There was no statistically significant change in the arch depth measurement when arch form was varied. The results showed greater …


Change In Bracket Bond Strength And Enamel Calcium : Due To Repeated Bonding With Conventional And Resinomer Glass Ionomer Cements, David L. Wilkinson Aug 1996

Change In Bracket Bond Strength And Enamel Calcium : Due To Repeated Bonding With Conventional And Resinomer Glass Ionomer Cements, David L. Wilkinson

Loma Linda University Electronic Theses, Dissertations & Projects

Glass ionomers chemically and mechanically bond to enamel. Repeated bonding may deplete calcium in enamel and reduce the bond strength. Seventy-five non-carious molars were randomly divided into three equal groups and metal brackets were bonded with either Ketac-Cem, Photac-Bond, or Fuji Ortho LC. The samples were stored in 100% humidity at 37° C for 7 days then shear/peel tested with an Instron machine. New brackets were repeatedly cemented with the same cement to the same tooth and shear/peel tested a total of five times. After each shear/peel test the tooth with the mean bond strength from each cement was set …