Short Versus Regular-Length Implants to Rehabilitate Partially Edentulous Mandible: A 2-Year Prospective Split-Mouth Clinical Study.

Many studies have evaluated short implants (SIs); however, it is still unclear whether SIs are reliable and can be used to simplify surgical and prosthetic protocols with successful clinical outcomes. The aim of this nonrandom, conveniently sampled, prospective, split-mouth study was to compare the clinical outcomes when short SI (≤8 mm) or regular-length implants (RIs; >10 mm) were used in the posterior mandible 2 years after the delivery of splinted reconstructions. Each participant (N = 10) received 4 implants in the posterior mandible; 2 SIs were placed on one side, and 2 RIs were placed contralaterally. Implants were restored with splinted, screw-retained, porcelain-fused-to-metal reconstructions. Survival and success rates, peri-implant marginal bone level (MBL), and soft-tissue parameters were evaluated. No participant dropouts were recorded. Both types of implants showed 100% success and survival rates. From prosthetic delivery to 24 months postloading, bone remineralization of +0.40 mm for the SIs and +0.36 mm for the RIs was observed without statistically significant differences in MBL between the implant types (P = .993). SIs showed significantly higher (P = .001) clinical attachment level and probing depth values. Chipping occurred in one situation in the RI group, resulting in a 97.5% prosthetic success rate, which was 100% for the SIs. After 2 years, SIs with splinted reconstructions showed comparable clinical outcomes to those of RIs. Further long-term controlled clinical studies with balanced experimental designs evaluating random and larger populations are required to corroborate these findings.

Digital workflow for the rehabilitation of the excessively worn dentition.

Excessively worn dentition is a clinical condition that mainly impacts the esthetic appearance of patients. In many cases, this may even extend to affect their psychologic condition and social interaction, and consequently reduce their quality of life. The treatment steps of such cases involve comprehensive evaluation and diagnosis, a rigid rehabilitation plan, and a careful and well-structured treatment execution. To facilitate long-term success, patient compliance and a strict recall program should be implemented. The case report presented in this article provides a step-by-step description of the treatment of an excessively worn dentition with the aid of the digital workflow.

Clinical and Radiographic Evaluation of Short Implants Placed in the Posterior Mandible: A 1-Year Pilot Split-Mouth Study.

In many cases, due to anatomical limitations, the placement of regular-length implants cannot be facilitated without the performance of advanced surgical procedures. However, these are associated with morbidity, prolonged treatment time, and costs. To overcome such disadvantages, short implants were introduced. The aim of this prospective pilot split-mouth study was to compare the clinical outcome between short implants (7 mm) and regular-length (≥10 mm) implants placed in the posterior mandible after 1 year of prosthetic delivery. Ten patients received 4 implants in the posterior mandible. Two short implants were placed in one side and 2 regular-length implants were placed contralaterally. These were restored by means of splinted screw-retained metal-ceramic crowns. Marginal bone loss (MBL) and soft-tissue parameters were compared. No implant failed. Both types of implants showed success rates of 90% and survival rates of 100%. From prosthetic delivery to 1 year post-loading a bone gain of +0.29 mm for short implants and +0.19 mm for regular-length implants was present without showing any statistically significant differences in MBL between the 2 implant types ( P > .05). Bleeding on probing, clinical attachment level, probing depth, and crown-to-implant ratio did not show any statistically significant differences between the 2 implant lengths ( P > .05). One case of chipping occurred in the regular-length implant group, leading to a prosthetic survival rate of 95%. Short implants showed a prosthetic survival rate of 100%. After 1 year, short implants showed comparable clinical outcomes to that of regular-length implants, making them a viable treatment option in the posterior mandible.

The Effect of UV Treatment on the Osteoconductive Capacity of Zirconia-Based Materials.

OBJECTIVE: Improvements in the bioactivity of zirconia implants for accelerated healing and reduced morbidity have been of continuing interest in the fields of dentistry and orthopedic surgery. The aim of the present study was to examine whether UV treatment increases the osteoconductivity of zirconia-based materials. MATERIALS AND METHODS: Smooth and rough zirconia-based disks and cylindrical implants were treated with UV light for 15 min and subsequently placed in rat femurs. Surface characterization was performed using scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contact angle measurements. RESULTS: In vivo histomorphometry revealed that the percentage of bone-implant contact and the amount of bone volume, formed around UV-treated implants, increased by 3-7-fold for smooth surfaces and by 1.4-1.7-fold for rough surfaces compared to non-treated specimens at Weeks 2 and 4 of healing, respectively. A biomechanical test showed that UV treatment accelerated the establishment of bone-zirconia integration and enhanced the strength of the bone-implant interface by two-fold. Additionally, surface characterization of the zirconia disks revealed that UV treatment decreased the amount of surface carbon and converted the hydrophilic status from hydrophobic to superhydrophilic. CONCLUSIONS: This study indicates that UV light pretreatment enhances the osteoconductive capacity of zirconia-based materials.

Wear behavior of zirconia substrates against different antagonist materials.

OBJECTIVE: This study assessed the wear behavior of different zirconia substrates with distinct surface roughness against different antagonist materials. METHOD: Hemisphere-shaped specimens (diameter 5 mm) made out of different materials (VM9, Vintage ZR, IPS e.max Press, and human enamel) were used as antagonists against plates of three zirconia materials (P-NANOZr, Cercon HT, and Zenostar) with different surface roughness (smooth [Ra = 0.01], moderate [Ra = 0.1], and rough [Ra = 1]). Each group (n = 7) was exposed to thermomechanical fatigue in a mastication simulator to simulate 5 years of clinical service. All specimens were scanned using a laser scanner and volumetric loss was quantified. Scanning electron microscopy was used to evaluate wear pattern, while Raman spectroscopy was employed to determine the crystalline property of zirconia specimens. RESULTS: For zirconia, the smallest volumetric loss was recorded with smooth P-NANOZR against enamel antagonists (0.002 ± 0.002 mm³), whereas the greatest loss was observed with rough Cercon HT against Vintage antagonists (0.37 ± 0.14 mm³). For antagonists, smooth Zenostar against enamel antagonists yielded the smallest volumetric loss (0.03 ± 0.02 mm³), whereas the greatest loss values were recorded with rough Zenostar against VM9 antagonists (2.67 ± 0.35 mm³). A positive correlation was found between surface roughness of zirconia specimens and volume loss of base and antagonist specimens. PNANOZR showed less wear compared to other zirconia materials. The wear pattern was comparable among different specimens. Artificial aging did not influence the levels of tetragonal and monoclinic phases of different zirconia materials. CONCLUSION: While microstructure shows a relatively smaller effect, surface roughness of zirconia has the greatest effect on its wear and on the wear of antagonists.

Treatment planning and dental rehabilitation of periodontally compromised partially edentulous patient: a case report - part II.

When planning a prosthetic rehabilitation of a periodontally compromised case, the clinician is often confronted with difficulties and dilemmas related to selecting the appropriate treatment that would provide long-term successful outcomes in function and esthetics. In such cases, a correct diagnosis and prognosis of the intraoral situation supported by evidence-based dentistry is the basis for the establishment of a proper treatment strategy. In this second part of a two-part treatment planning series, a systematic approach of patient examination and prognosis of each tooth is presented. Furthermore, different removable and fixed treatment possibilities are described and the rationale governing the decision-making process is revealed. The execution of the final treatment plan as specified by the concept of comprehensive dental care is outlined, and the final outcome is discussed according to the literature.

Treatment planning and dental rehabilitation of a periodontally compromised partially edentulous patient: a case report - Part I.

When planning a prosthetic rehabilitation of a periodontally compromised case, the clinician is often confronted with difficulties and dilemmas related to selecting the appropriate treatment modality that would provide a long-term longevity in terms of function and esthetics. In such cases, a correct diagnosis and prognosis of the intraoral situation supported by evidence-based dentistry is the basis for the establishment of a proper treatment strategy. In this two-part treatment planning series, a systematic approach of patient examination and prognosis of each tooth is presented. Furthermore, different removable and fixed treatment possibilities are described and the rationale governing the decision-making process is revealed. The execution of the final treatment plan as specified by the concept of comprehensive dental care is outlined and the final outcome is discussed according to the literature.

Single dental implant retained mandibular complete dentures--influence of the loading protocol: study protocol for a randomized controlled trial.

BACKGROUND: Over the years, there has been a strong consensus in dentistry that at least two implants are required to retain a complete mandibular denture. It has been shown in several clinical trials that one single median implant can retain a mandibular overdenture sufficiently well for up to 5 years without implant failures, when delayed loading was used. However, other trials have reported conflicting results with in part considerable failure rates when immediate loading was applied. Therefore it is the purpose of the current randomized clinical trial to test the hypothesis that immediate loading of a single mandibular midline implant with an overdenture will result in a comparable clinical outcome as using the standard protocol of delayed loading. METHODS/DESIGN: This prospective nine-center randomized controlled clinical trial is still ongoing. The final patient will complete the trial in 2016. In total, 180 edentulous patients between 60 and 89 years with sufficient complete dentures will receive one median implant in the edentulous mandible, which will retain the existing complete denture using a ball attachment. Loading of the median implant is either immediately after implant placement (experimental group) or delayed by 3 months of submerged healing at second-stage surgery (control group). Follow-up of patients will be performed for 24 months after implant loading. The primary outcome measure is non-inferiority of implant success rate of the experimental group compared to the control group. The secondary outcome measures encompass clinical, technical and subjective variables. The study was funded by the Deutsche Forschungsgemeinschaft (German research foundation, KE 477/8-1). DISCUSSION: This multi-center clinical trial will give information on the ability of a single median implant to retain a complete mandibular denture when immediately loaded. If viable, this treatment option will strongly improve everyday dental practice. TRIAL REGISTRATION: The trial has been registered at Deutsches Register Klinischer Studien (German register of clinical trials) under DRKS-ID: DRKS00003730 since 23 August 2012. (http://www.germanctr.de).