Interproximal contact loss between implant restorations and adjacent natural teeth: A systematic review and meta-analysis.

PURPOSE: This systematic review was conducted to evaluate the prevalence of interproximal contact loss (ICL) between implant restorations and adjacent teeth in relation to age, gender, follow-up time, and arch location. METHODS: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was registered in the Open Science Framework (OSF). The formulated population, intervention, comparison, outcome (PICO) question was "What is the prevalence of the ICL between implant restoration and adjacent teeth?" The search strategy used four main electronic databases and an additional manual search was performed until February 2023. Clinical studies that evaluated the prevalence of interproximal open contact between implant restorations and adjacent teeth were included. A qualitative analysis for clinical studies was used to assess the risk of bias. In addition, a single-arm meta-analysis of proportion was performed to evaluate the percentage of mesial versus distal open contact and total ICL between implant restoration and adjacent teeth. RESULTS: Fifteen studies published between 2014 and 2023 met the eligibility criteria. Seven studies presented ICL rates higher than 20%. All studies evaluated ICL in posterior regions (molar, premolar area). Five studies had an ICL rate lower than 50% and three studies had an ICL rate higher than 50%. One study assessed the interproximal contact at three months post-restoration insertion, four studies assessed the interproximal contact at 1-year follow-up and nine studies evaluated the interproximal contact over 2 years of follow-up. Mesial and distal ICL rates were 44.2% (95% CI: 30.6% to 58.6%) and 27.5% (95% CI: 10.5% to 55.0%), respectively. The heterogeneity between studies was high (I2 (95% CI) = 87.8% (75.9% to 93.8%). CONCLUSION: Based on the results of the included studies, the prevalence of ICL was high, occurring more frequently at the mesial contact. There were no significant differences in relation to age, gender, and arch location.

Managing Gag Reflex during Removable Partial Denture Treatment: A Review and a Clinical Report.

A gag reflex is a common occurrence during dental procedures. A hypersensitive gag reflex is less frequently encountered and may prevent the dental provider from successfully completing critical clinical stages, resulting in poor treatment outcomes. Once patients suffer an unpleasant gag reflex experience in a dental office, they may become phobic, delaying or postponing their dental treatment. The purpose of this article is to review available treatment options and present a report of a partially edentulous patient with an exaggerated gag reflex, focusing on clinical management using a simple yet effective table salt technique and proper prosthesis design.

Integrating conventional and CAD/CAM digital techniques for establishing canine protected articulation: A clinical report.

Canine protected articulation is widely accepted for patients requiring extensive oral rehabilitation. Computer-aided design and computer-aided manufacturing (CAD/CAM) restorations have been primarily designed in occlusion at the maximum intercuspal position. Designing a virtual articulator that is capable of accepting excursive occlusal records and duplicating the mandibular movements is a challenge for CAD/CAM technology. Modifying tooth shape using composite resin trial restorations to produce esthetic results and later scanning the modified teeth to create milled crowns is becoming a popular use of the CAD/CAM technology. This report describes a technique that combines conventional and CAD/CAM prosthodontic techniques for milling crowns for canine teeth that are designed to establish or improve canine protected articulation. This technique involves designing and fabricating interim restorations based on diagnostic waxing, scanning the designs intraorally, and storing them in software as pretreatment digital records. The scanned designs are then applied to the digital representation of the prepared teeth to fabricate the definitive restorations.

A Single Visit Direct Technique to Provisionally Restore Occlusion for a Full-Mouth Rehabilitation: A Clinical Report.

Attrition of the dentition can negatively affect esthetics and function. When reconstructing patients with attrition who require restoration at increased occlusal vertical dimension (OVD), it is necessary to first evaluate the OVD using a removable interim prosthesis to ensure that the patient will tolerate the new position. The transition to fixed interim prostheses has to be carefully planned to achieve the desired OVD. One approach is to prepare all teeth in a single day and place full-arch interim prostheses; however, this can be tiring for the patient and prosthodontist. An alternative approach is to prepare one arch and place interim prostheses, while using composite resin in the opposing arch to maintain the newly established OVD. A diagnostic wax-up at the proposed OVD is completed and duplicated in stone. A vacuform matrix is loaded with composite resin and applied to the unprepared etched teeth of the opposing arch to restore form and occlusion until full contour interim prostheses are placed at a later visit.

Impression Making and Lab Work Authorization Forms in Fixed Prosthodontics: A Preclinical Exercise.

INTRODUCTION: Making a final impression using a custom tray for fixed prosthodontics is a widely accepted procedure that is taught in many dental schools. As such, achieving competency in impression making and lab communication is a new Commission on Dental Accreditation curriculum requirement for all dental schools in the US. METHODS: This resource presents an instructional slide show on the clinical steps required in fabricating a custom tray using a visible light-cured resin, making a successful impression, and writing a work authorization form for the fabrication of a fixed dental prosthesis. The presentation also contains a brief overview of alternative techniques and materials used as well as basic points for self-evaluation for the custom tray and the final impression. This activity was conducted as a small-group team-based learning exercise in a preclinical setting, where a self-assessment form was provided for students to evaluate their work. RESULTS: Examiners indicated that students who completed this exercise had a deeper understanding of the sequencing of steps involved in the construction of a fixed partial denture as well as better lab communication skills compared to students from previous classes who did not participate in the exercise. DISCUSSION: The preclinical setting provided students with a relaxed atmosphere for fabricating a custom tray using visible light-curing material. This exercise is part of a larger preclinical exercise that takes students through all the steps involved in the fabrication of a fixed dental prosthesis, from impression making to the evaluation of the framework made by the lab.

Digital Denture Fabrication in Pre- and Postdoctoral Education: A Survey of U.S. Dental Schools.

PURPOSE: To survey chairs of prosthodontics or restorative departments and program directors of postdoctoral prosthodontic programs in the United States regarding digital denture fabrication. The key objectives of the survey were to identify the current trends in complete denture fabrication using CAD/CAM technology and to determine how and to what extent this technique is taught and used in U.S. pre- and postdoctoral prosthodontic programs. MATERIALS AND METHODS: An invitation to participate in an online survey was sent to 52 prosthodontics/restorative chairs of U.S. dental schools and to all of the 50 program directors of postdoctoral prosthodontics programs. A version of the survey with the same questions was sent to a national sample of prosthodontics/restorative chairs and program directors of postdoctoral prosthodontics. The 20-item survey took approximately 15 minutes to complete. Dependent samples paired t-test was run on items that were the same in both surveys. RESULTS: The response rate for the survey was 63% for department chairs and 44% for program directors. All respondents with the exception of one department chair were aware of CAD/CAM technology used for denture fabrication. More than half of the program directors (52.4%) compared to 12.1% of chairs have incorporated some aspects of CAD/CAM denture fabrication technology into their curriculum. When asked if the fabrication cost prevented introducing this technology in the predoctoral/postdoctoral curriculum, 52.4% of the department chairs affirmed this response compared to 12.1% of the program directors. There was a significant difference between groups when asked if they had incorporated the CAD/CAM denture fabrication technique into the postgraduate/predoctoral curriculum. Department chairs reported less usage of CAD/CAM technology. Only 12.1% of department chairs reported using some aspects of CAD/CAM technology in the predoctoral curriculum compared to 52.4% in the postdoctoral curriculum (F = 13.528, p ≤ 0.001). While this technology is used in four predoctoral clinics, none of the chairs reported including CAD/CAM denture fabrication in their preclinical complete denture courses. For the schools using the technology, 33.3% of postdoctoral and 30.3% of predoctoral programs use it to make a denture with a try-in step; however, 19% of the postdoctoral and 18.2% of predoctoral programs process the dentures without a try-in appointment. Slightly less than half (42.9%) of graduate programs are using the technology to make just the denture bases. Only a small proportion (10% or less) of the total number of dentures processed in post- and predoctoral programs are made using CAD/CAM technology. The proportion of postdoctoral programs that process cases using CAD/CAM technology was significantly higher than in predoctoral programs (F = 5.106, p ≤ 0.028). Many schools indicated that they are in a "trial phase" to evaluate the technique, especially at the predoctoral level. Also, 19% (n = 4) of postdoctoral and 15.2% (n = 5) of predoctoral respondents have created continuing education courses. Of postdoctoral programs, 38.1% (n = 8) plan to introduce this technology at some point in the near future (next 1 to 4 years); 27.3% of predoctoral programs plan to as well. CONCLUSIONS: All program directors and department chairs who participated in the survey are aware of this technology with the exception of one department chair. More than half of the program directors reported that they have incorporated this technology in their curricula compared to only 12% of department chairs. Currently, only 10% or less of complete denture cases are processed using the CAD/CAM technology, at either the post- or predoctoral levels. Both groups reported that the main use of this technology is for the fabrication of denture bases and for processing dentures including the try-in step. The majority of respondents in both groups indicated they plan to add digital denture fabrication into their curricula within the next 1 to 4 years.

Evaluation of Team-Based Learning and Traditional Instruction in Teaching Removable Partial Denture Concepts.

The aim of this study was to evaluate the effectiveness of team-based learning (TBL) methodology on dental students' retention of knowledge regarding removable partial denture (RPD) treatment. The process of learning RPD treatment requires that students first acquire foundational knowledge and then use critical thinking skills to apply that knowledge to a variety of clinical situations. The traditional approach to teaching, characterized by a reliance on lectures, is not the most effective method for learning clinical applications. To address the limitations of that approach, the teaching methodology of the RPD preclinical course at the University of Florida was changed to TBL, which has been shown to motivate student learning and improve clinical performance. A written examination was constructed to compare the impact of TBL with that of traditional teaching regarding students' retention of knowledge and their ability to evaluate, diagnose, and treatment plan a partially edentulous patient with an RPD prosthesis. Students taught using traditional and TBL methods took the same examination. The response rate (those who completed the examination) for the class of 2013 (traditional method) was 94% (79 students of 84); for the class of 2014 (TBL method), it was 95% (78 students of 82). The results showed that students who learned RPD with TBL scored higher on the examination than those who learned RPD with traditional methods. Compared to the students taught with the traditional method, the TBL students' proportion of passing grades was statistically significantly higher (p=0.002), and 23.7% more TBL students passed the examination. The mean score for the TBL class (0.758) compared to the conventional class (0.700) was statistically significant with a large effect size, also demonstrating the practical significance of the findings. The results of the study suggest that TBL methodology is a promising approach to teaching RPD with successful outcomes.

A conservative approach to rebasing an implant-retained fixed complete denture.

After years of service, the acrylic resin base of an implant-retained fixed complete dental prosthesis may need to be replaced because of the wear of the acrylic resin teeth. The most common methods used by dental laboratories to remove the acrylic resin from the metal framework are either burning with a flame or grinding. Both of these methods risk exposing the dental laboratory technician to hazardous by-products and damaging or contaminating the metal framework or the gold cylinders. This article presents a safe approach to removing acrylic resin while preserving the integrity of the framework. The technique involves heating the prosthesis to beyond the glass transitional temperature of the acrylic resin to allow the resin to be safely peeled off the framework.

A comparative study of the accuracy between plastic and metal impression transfer copings for implant restorations.

PURPOSE: A precise transfer of the position and orientation of the antirotational mechanism of an implant to the working cast is particularly important to achieve optimal fit of the final restoration. This study evaluated and compared the accuracy of metal and plastic impression copings for use in a full-arch mandibular edentulous simulation with four implants. MATERIALS AND METHODS: Metal and plastic impression transfer copings for two implant systems, Nobel Biocare™ Replace and Straumann SynOcta®, were assessed on a laboratory model to simulate clinical practice. The accuracy of producing stone casts using these plastic and metal impression transfer copings was measured against a standard prosthetic framework consisting of a cast gold bar. A total of 20 casts from the four combinations were obtained. The fit of the framework on the cast was tested by a noncontact surface profilometer, the Proscan 3D 2000 A, using the one-screw test. The effects of implant/system and impression/coping material on gap measurements were analyzed using repeated measures ANOVA. RESULTS: The findings of this in vitro study were as follows: plastic copings demonstrated significantly larger average gaps than metal for Straumann (p = 0.001). Plastic and metal copings were not significantly different for Nobel (p = 0.302). Nobel had significantly larger average gaps than Straumann for metal copings (p = 0.003). Nobel had marginally smaller average gaps than Straumann (p = 0.096) for plastic copings. The system-by-screw location interaction was significant as well (p < 0.001), indicating significant differences among the four screw locations, but the location differences were not the same for the two systems. A rank transformation of the data was necessary due to the nonnormal distribution of the gap measurements. No adjustments were made for multiple comparisons. CONCLUSIONS: The metal impression copings were more accurate than plastic copings when using the Straumann system, and there was no difference between metal and plastic copings for the Nobel Replace system. The system-by-screw location was not conclusive, showing no correlation within each system.

Stabilized record base for implant treatment.

It is important to obtain an accurate interocclusal record for the restoration of patients undergoing implant treatment. Atrophic alveolar bone in the mandible not only limits the placement of implants, but also contributes to deficient ridge morphology resulting in unstable record bases. Securing the record base to the implants is a useful way to obtain an accurate registration. The technique presented in this article uses two widely spaced implants as the optimal number of implants to stabilize record bases.

Preservation of existing soft-tissue contours in the transition from a tooth to an implant restoration in the esthetic zone using a flapless approach: a clinical report.

Two-stage placement of a dental implant is a well-established method for restoring a missing anterior tooth; however, replacement of an anterior tooth by using two-stage implant surgery may result in changes in the interdental papilla height and loss of alveolar bone with compromised esthetic results. Alternatively, the use of a one-stage minimally invasive surgical technique followed by immediate provisionalization may facilitate achievement of esthetic and functional success with minimal discomfort and clinical time. This article presents a clinical case with a single anterior tooth replacement, illustrating ridge preservation with healing, delayed implant placement with immediate provisionalization of the implant to support the soft tissue, and a method of recording the soft-tissue contour in the final impression to achieve an optimal esthetic result.

Effect of dental students as instructors on preclinical performance in prosthodontics.

Dental schools continue to have difficulty recruiting and retaining faculty. One approach to augment student learning would be to train and utilize senior dental students as instructors in preclinical courses. This study was undertaken to evaluate the effect of using senior dental students as instructors on the performance of second-year students in two preclinical prosthodontic courses. In the spring term of 2007, four senior dental students and four or five full-time faculty were assigned as instructors for the fixed prosthodontics and complete denture prosthodontics preclinical courses. Each course has previously been conducted with a total of seven to nine faculty instructors. The performance of two groups of second-year students on preclinical projects was compared based upon their source of instruction for the project. The scores for the two groups were compared using the Wilcoxon rank sum tests and the corresponding 95 percent confidence intervals for the median difference in scores for the two instructor types. This study found no significant difference in performance between sophomore students instructed by full-time faculty or those instructed by senior dental students in either the fixed or removable prosthodontics preclinical courses (p>.05). The use of senior dental students as instructors in the preclinical prosthodontics courses may be one option to partially address the shortage of full-time dental faculty.

Eleven-year report on a predoctoral implant dentistry program.

PURPOSE: An elective program on implant dentistry was started in the summer of 1994 at the University of Detroit Mercy School of Dentistry (UDM). The program provides comprehensive didactic and clinical training in implant dentistry to a select group of senior dental students. This study describes the program and clinical results of the first 11 years of the elective program in implant dentistry at UDM. MATERIALS AND METHODS: The program is 1 year long and is offered to a group of 10 senior students out of a class of 72. In addition to a one-semester lecture course offered to all dental students, students in the elective program participate in a one-semester seminar which includes literature review and "hands-on" surgical and prosthodontic components. Patients are assigned during the summer term to students who work in pairs. Students actively participate in diagnosis and treatment planning, assist in surgery, and accomplish the prosthodontic procedures. Prosthodontic services include single-tooth restorations, multiple-unit fixed restorations, overdentures, and full-arch fixed prostheses. A retrospective analysis of the patients treated in the first 11 years of the program was conducted. RESULTS: During the first 11 years of the program, 159 implants were placed in 70 patients. There were a total of 10 failed implants in seven patients (failure rate 6.3%): eight implants prior to loading and two following loading. Minor complications included gold screw loosening, gold screw fracture, porcelain fracture, and soft tissue inflammation, which occurred in less than 5% of the patients. CONCLUSIONS: The rates of implant failure and complications in the first 11 years of the elective implant program at UDM appear to be within an acceptable range when compared to other educational programs and studies reported in the dental literature.

Evaluation of dental students as instructors in preclinical prosthodontics and occlusion courses.

PURPOSE: While facing a shortage of faculty members, dental schools need to be innovative in their educational methodologies. One approach to augment student learning would be to mentor dental students as participating faculty in current courses. A study was undertaken to evaluate dental students as instructors in preclinical prosthodontics and occlusion courses. MATERIALS AND METHODS: In spring term 2003, three senior dental students (4DN) and four full-time faculty were assigned as faculty for each of two preclinical courses: fixed prosthodontics and complete denture prosthodontics. In the summer term 2003, two junior dental students (3DN) and five full-time faculty were assigned to teach in the occlusion preclinical course. Each course had previously been conducted with a total of seven full-time faculty. Three types of outcome assessment were accomplished: (1) evaluation by the 2DN students of full-time faculty and student instructors at the end of the course using a standardized university scale of 1 (poor) to 5 (excellent); (2) a survey of student instructors about their experience; and (3) a course debriefing with selected 2DN students. RESULTS: The overall mean instructor-quality score assigned to the student instructors, 4.5 (SD, 0.7), was slightly higher than that of faculty instructors, 4.2 (SD, 0.9). Student instructors were rated higher than or equal to full-time faculty based on the mean response scores for all ten evaluation questions. The greatest difference between faculty and student ratings was in the category of "respect and concern for the students" in all courses. In addition, information gathered from eight student instructors indicated that the experience was a very positive one overall with an increased interest in an academic career noted. Comments from the 2DN students in the debriefing sessions were positive about having student instructors. CONCLUSIONS: This study demonstrated that from the perspective of second year dental students, senior and junior dental students were accepted as preclinical instructors in prosthodontics and occlusion preclinical courses. Additionally, senior and junior students who participated in student teaching had a positive experience. The use of dental students as preclinical faculty in prosthodontics and occlusion appears to be a viable approach for mentoring students in careers in academics, providing student instructors with higher learning experiences, and supplementing the efforts of full-time faculty.

Classification system for the completely dentate patient.

The American College of Prosthodontists (ACP) has developed a classification system designed for use by dental professionals in the diagnosis and treatment of completely dentate patients. This classification is the third in a series and is similar to the Classifications for Complete Edentulism and Partial Edentulism previously developed by the ACP. These guidelines are intended to aid practitioners in the systematic diagnosis of each patient which, in turn, should lead to an appropriate treatment. Four categories of a completely dentate situation are defined (Class I-IV), differentiated by specific diagnostic criteria, with Class I representing an uncomplicated clinical situation and Class IV representing the most complex clinical situation. Potential benefits of the system include (1) improved intraoperator consistency, (2) improved professional communication, (3) insurance reimbursement commensurate with complexity of care, (4) an improved screening tool for dental school admission clinics, (5) standardized criteria for outcomes assessment and research, (6) enhanced diagnostic consistency, and (7) a simplified aid in the decision-making process associated with referral.

Classification system for partial edentulism.

The American College of Prosthodontists (ACP) has developed a classification system for partial edentulism based on diagnostic findings. This classification system is similar to the classification system for complete edentulism previously developed by the ACP. These guidelines are intended to help practitioners determine appropriate treatments for their patients. Four categories of partial edentulism are defined, Class I to Class IV, with Class I representing an uncomplicated clinical situation and class IV representing a complex clinical situation. Each class is differentiated by specific diagnostic criteria. This system is designed for use by dental professionals involved in the diagnosis and treatment of partially edentulous patients. Potential benefits of the system include (1) improved intraoperator consistency, (2) improved professional communication, (3) insurance reimbursement commensurate with complexity of care, (4) improved screening tool for dental school admission clinics, (5) standardized criteria for outcomes assessment and research, (6) enhanced diagnostic consistency, and (7) simplified aid in the decision to refer a patient.

Implant dentistry in predoctoral education: the elective approach.

In response to interest by dental students and patient needs, an elective program in implant dentistry was started at the University of Detroit Mercy School of Dentistry (UDM) in the summer of 1994. The 1-year program is offered to a group of 10 senior students out of a class of 72. Implant treatment is provided to selected edentulous and partially edentulous patients. Predoctoral students participate in diagnosis and treatment planning, assist in surgical placement, and perform the prosthodontic procedures. A survey was sent to 160 UDM graduates, and 90 responded. Out of the 90 respondents, 35% had participated in the elective implant program and 65% had not. A Pearson correlation matrix was used to analyze their responses. A stronger positive correlation with offering and restoring implants was seen in graduates who had completed the elective program in implant dentistry.