A Technique to Record and Transfer the Distance Between the Bone Crest and the Interproximal Contact Point to the Dental Laboratory to Maintain the Interdental Papilla While Fabricating Implant Supported Restorations.

The interdental papilla plays an important role in terms of esthetics and function. Management of the interdental papilla, especially around implants can be challenging. One of the factors mentioned in the literature that affects the viability of the papilla is the distance of the interdental contact point from the crest of the bone. The following case report describes a technique to predictably achieve an interdental contact area within the proper distance from the crest of the bone to help maintain the papilla for the long term.

Digital Custom Impression Technique to Record Emergence Profile and Fabrication of an Esthetic Implant Supported Restoration.

One of the challenges in esthetic implant supported restorations is to replicate the emergence profile of soft tissue contours created by provisional restorations. Various analog techniques have been used to achieve the most esthetic and natural emergence profile in final restorations. The evolution of digital dentistry has made dentistry easier and efficient albeit with a learning curve. The technique described here uses digital technology to describe a complete digital workflow from the provisional stage to the final restoration.

Immediate versus delayed loading of mandibular implant-retained overdentures: A 60-month follow-up of a randomized clinical trial.

AIM: The purpose of this observational, post-trial follow-up study was to evaluate 60-month outcomes of a randomized controlled clinical trial that compared immediately and delayed loaded two unsplinted implants, supporting a locator-retained mandibular overdenture. MATERIALS AND METHODS: Patients from a randomized controlled clinical trial, treated with either immediate or delayed loading of two implants, supporting a locator-retained mandibular overdenture, were recalled for 60-month evaluation. Patients underwent a clinical and radiographic examination to evaluate the peri-implant soft tissue parameters and bone. Prosthetic maintenance needs and complications were also recorded. RESULTS: Twenty three of the 30 patients were available for the 60-month follow-up. The mean radiographic bone level change measured using standardized periapical radiographs from baseline to 60 months was 0.89 mm (±0.74) and 0.18 (±0.41) for delayed loading and immediate loading groups, respectively. A statistically significant difference was observed at 60 months with a smaller radiographic bone level change in the immediate loading group. No implants were lost between 12 and 60 months. At 60 months, per-protocol implant survival rate was 100% for both the groups. No difference was found in the peri-implant soft tissue parameters and prosthetic needs between the groups. CONCLUSION: Both immediately and delayed loaded implants supporting a locator-retained mandibular overdenture showed similar clinical outcomes.

Analyzing Dental Implant Sites From Cone Beam Computed Tomography Scans on a Tablet Computer: A Comparative Study Between iPad and 3 Display Systems.

PURPOSE: The aim of this study was to compare a medical-grade PACS (picture archiving and communication system) monitor, a consumer-grade monitor, a laptop computer, and a tablet computer for linear measurements of height and width for specific implant sites in the posterior maxilla and mandible, along with visualization of the associated anatomical structures. MATERIAL AND METHODS: Cone beam computed tomography (CBCT) scans were evaluated. The images were reviewed using PACS-LCD monitor, consumer-grade LCD monitor using CB-Works software, a 13″ MacBook Pro, and an iPad 4 using OsiriX DICOM reader software. The operators had to identify anatomical structures in each display using a 2-point scale. User experience between PACS and iPad was also evaluated by means of a questionnaire. RESULTS: The measurements were very similar for each device. P-values were all greater than 0.05, indicating no significant difference between the monitors for each measurement. The intraoperator reliability was very high. The user experience was similar in each category with the most significant difference regarding the portability where the PACS display received the lowest score and the iPad received the highest score. CONCLUSIONS: The iPad with retina display was comparable with the medical-grade monitor, producing similar measurements and image visualization, and thus providing an inexpensive, portable, and reliable screen to analyze CBCT images in the operating room during the implant surgery.

Marginal Bone Response Around Immediate- and Delayed-Loading Implants Supporting a Locator-Retained Mandibular Overdenture: A Randomized Controlled Study.

PURPOSE: Implant-supported mandibular overdentures (OVDs) have been proposed as the gold standard for the treatment of edentulous mandibles. There is limited evidence on the clinical outcomes of immediate loading of two unsplinted implants supporting a mandibular OVD. The purpose of this randomized controlled trial was to evaluate the performance of two unsplinted implants supporting a Locator-retained mandibular OVD over 12 months loaded immediately or after a delay. MATERIALS AND METHODS: Each patient received two implants 4.0 mm in diameter and 8 to 15 mm long. Locator-retained mandibular OVDs were connected to the implants either immediately (IL) or 3 months postsurgery (DL). The primary response variable was radiographic bone loss (RBL) at 6 and 12 months postsurgery. Implant length, insertion torque, implant failure, prevalence of maintenance visits, and prosthetic complications were also recorded. RESULTS: Thirty participants (15 in the IL and 15 in the DL groups) were evaluated at 12 months. The implant cumulative survival rates were 100% and 93% for DL and IL, respectively. The mean RBL from baseline to 1 year was 0.54 (± 0.5) mm and 0.25 (± 0.5) mm for DL and IL, respectively. A statistically significant difference was observed at 12 months, with less RBL in the IL group. Insertion torque and implant length were not correlated with RBL. Also, no difference in frequency of maintenance visits and prosthetic complications was reported between the groups. CONCLUSION: Immediate loading of two unsplinted implants supporting a Locator-retained mandibular OVD seems to be a suitable treatment option. Significantly less RBL was observed after 1 year of loading around IL implants than around DL implants. Furthermore, neither implant length nor insertion torque seemed to affect RBL 1 year after surgical placement.

Prospective cohort pilot study of 2-visit CAD/CAM monolithic complete dentures and implant-retained overdentures: Clinical and patient-centered outcomes.

STATEMENT OF PROBLEM: Presently, no studies have evaluated clinical outcomes or patient-centered outcomes for complete dentures fabricated with computer-aided design and computer aided manufacturing (CAD/CAM) technology. PURPOSE: The purpose of this prospective cohort pilot study was to evaluate the clinical and patient-centered outcomes for CAD/CAM monolithic dentures fabricated in 2 visits. MATERIAL AND METHODS: Twenty participants with an existing set of maxillary complete dentures opposing either mandibular complete dentures or implant-retained overdentures that required replacement were recruited in this study. A 2-visit duplicate denture protocol was used to fabricate 40 arches of monolithic dentures with CAD/CAM technology. A 100-mm visual analog scale (VAS) instrument was then used to record 12 outcomes at baseline and at 1-year follow-up. Predetermined values were assigned to grade the VAS rating of each outcome as favorable (70.1-100) and unfavorable (≤70). Favorable ratings were sub-divided as excellent (90.1-100), good (80.1-90), and fair (70.1-80). The clinical outcomes were evaluated independently by 2 experienced prosthodontists at baseline and at 1-year follow-up. Patients evaluated the corresponding patient-centered outcomes during the same time intervals. Additional descriptive variables were also recorded. Each clinical and patient-centered outcome was summarized by medians and ranges. Differences in all ratings recorded at baseline and at 1 year were tested by 1-sided sign test (α=.05). RESULTS: Of 20 participants, 3 were lost to follow-up, and 3 were unsatisfied with the digital dentures and withdrew from the study. These 3 participants were considered treatment failures. Of the 14 remaining participants, 9 had implant-retained mandibular overdentures, and 5 had conventional mandibular complete dentures. For clinical outcomes, the 12 studied outcomes were favorably evaluated by the 2 prosthodontist judges at the 1-year follow-up. Evaluations showed minimal differences between baseline and 1 year. An average of 5 emails (0-11) per patient were sent to the laboratory technicians to communicate the improvisation the CAD design of the dentures. An average of 3.3 denture adjustments were needed after insertion (0-10) during the 1-year period. For patient-centered outcomes, median ratings of all 14 participants indicated each of the 12 studied outcomes was favorable at the 1-year recall. Statistically significant improvements in patient ratings from baseline to 1 year were observed for the absence of denture sore spots and treatment time to make the dentures (P<.05). Minor complications related to loss of retention, excessive wear of teeth and the need for additional visits were observed in 5 participants. No other adverse clinical outcomes related to the CAD/CAM dentures were noted in the 14 evaluated participants, and all dentures were intact and in good condition at the 1-year follow-up. CONCLUSIONS: Clinical and patient-centered outcomes for CAD/CAM monolithic dentures fabricated using a 2-visit protocol were evaluated favorably at a 1-year follow-up. However, the proportion of excellent and good ratings for overall satisfaction and assessment was higher for patients than clinicians. A considerable amount of the clinician's time and effort was devoted to aiding in the digital process for the fabrication of CAD/CAM dentures.

Evaluation of linear measurements of implant sites based on head orientation during acquisition: An ex vivo study using cone-beam computed tomography.

PURPOSE: This study evaluated the effect of various head orientations during cone-beam computed tomography (CBCT) image acquisition on linear measurements of potential implant sites. MATERIALS AND METHODS: Six dry human skulls with a total of 28 implant sites were evaluated for seven different head orientations. The scans were acquired using a Hitachi CB-MercuRay CBCT machine. The scanned volumes were reconstructed. Horizontal and vertical measurements were made and were compared to measurements made after simulating the head position to corrected head angulations. Data was analyzed using a two-way ANOVA test. RESULTS: Statistical analysis revealed a significant interaction between the mean errors in vertical measurements with a marked difference observed at the extension head position (P<0.05). Statistical analysis failed to yield any significant interaction between the mean errors in horizontal measurements at various head positions. CONCLUSION: Head orientation could significantly affect the vertical measurements in CBCT scans. The main head position influencing the measurements is extension.

Immediate Placement and Restoration of an Implant in an Infected Socket in the Esthetic Zone.

INTRODUCTION: Despite recent reports on immediate implant placement in infected sockets, it remains unclear whether positive functional and esthetic results are repeatable in treating teeth with periapical infections. This case report describes important diagnostic factors and decision-making steps in the treatment planning of a fractured tooth with a periapical lesion in the anterior maxilla. CASE PRESENTATION: A healthy, non-smoking 36-year-old male patient presented with the chief complaint of trauma to the right maxillary central incisor. Radiographs displayed horizontal root fracture and a periapical lesion. Treatment comprised extraction of the fractured tooth with minimal trauma, followed by immediate implant placement and provisionalization. Clinical and radiographic analyses at 12 months after surgery showed maintenance of soft- and hard-tissue configuration and symmetry with the contralateral tooth. CONCLUSIONS: A multidisciplinary approach and careful case selection are of utmost importance for the successful treatment of challenging implant therapy. This case report shows esthetic and functional results 1 year after the immediate placement and functional loading of an implant in an infected socket in the esthetic zone.

Analysis of dimensional changes in the screw and the surface topography at the interface of a titanium screw and a zirconia abutment under cyclic loading: an in vitro study.

PURPOSE: The purpose of this experiment was to analyze the mechanics of the ceramic abutment-implant joint and the dimensional changes in the abutment screws from cyclic loading. MATERIALS AND METHODS: Two groups of experimental assemblies were used, one with zirconia abutments and the other with titanium abutments (n = 10). Each specimen consisted of an implant, an abutment, and a metal crown affixed in an acrylic resin base. The specimens were subjected to cyclic loading of 200 N for 1 million cycles at 10 Hz. After loading, a torque-angle signature analysis was done, the dimensions of the screws were measured, and the implant-abutment interfaces were examined with scanning electron microscopy. RESULTS: There was a statistically significant increase in the total length of the screws: 121 µm in the titanium group versus 88 µm in the zirconia group (P < .004). Microscopic analysis showed collected debris on the zirconia abutment undersurface and the screws. A statistically similar decrease in torque was observed: 18% for zirconia versus 13.5% for titanium. Radiographic microanalysis revealed that the debris collected in the zirconia assemblies was essentially a collection of titanium, vanadium, and aluminum, with traces of zirconium. CONCLUSIONS: While there was a loss of torque in both types of abutments, the stability of the zirconia abutment-implant joint was not affected by the loading. The study provides a better understanding of zirconia abutments, screw designs, and the mechanism holding together the implant-abutment assembly.