Relationship between Implant Length and Implant Stability of Single-Implant Restorations: A 12-Month Follow-Up Clinical Study.

Background and Objectives: Implant stability in vivo is contingent on multiple factors, such as bone structure, instrument positioning and implant surface modifications, implant diameter, and implant length. Resonance-frequency analysis is considered a non-invasive, reliable, predictable, and objective method by which to evaluate implant stability, due to its correlation with bone-to-implant contact. The purpose of this study was to evaluate the effect of implant length on the primary and secondary stability of single-implant crown rehabilitations, as measured by resonance-frequency analysis at different times. Materials and Methods: Implants of 10 and 11.5 mm were placed, and the resonance frequency was measured at the time of surgery (T0), as well as at 3 (T1), 6 (T2), and 12 (T3) months post-surgery. Results: A total of 559 implants were placed in 195 patients. Significant differences were observed when comparing the implant stability quotient (ISQ) values at T1, with values for 10-mm implants being greater than those for 11.5-mm implants (p = 0.035). These differences were also observed when comparing ISQ values for buccal and lingual areas. At T0, T2, and T3, no significant differences in ISQ values were observed. The use of 10-mm implants in the anterior maxilla yielded significantly greater values at T0 (p = 0.018) and T1 (p = 0.031) when compared with 11.5-mm implants. Significant differences in measurements were observed only for buccal areas (p = 0.005; p = 0.018). When comparing the sample lengths and sex, women with 11.5-mm implants showed significantly lower results than those with 10-mm implants (p < 0.001). Conclusions: There is a direct relationship between implants of a smaller length and greater ISQ values, with this relationship being most evident in the maxilla and in women.

Potential Deviation Factors Affecting Stereolithographic Surgical Guides: A Systematic Review.

OBJECTIVE: The aim of this study was to review potential deviation factors in stereolithographic surgical guides for dental implantology, warnings, and limitations of the system. METHODS: An electronic search in databases EMBASE, the Cochrane Library, and PubMed were conducted by 3 researchers to collect information on the accuracy of static computer-guided implant placement to summarize and analyze the overall accuracy. The latter included a search for correlations between factors such as support (teeth/mucosa/bone), number of templates, use of fixation pins, jaw, template production, guiding system, and guided implant placement in articles related to guided surgery with stereolithographic static systems. Studies published between 2012 and 2017 were reviewed. RESULTS: From 761 identified articles, a total of 24 articles were reviewed, which included 2767 dental implants. Data from studies analysis had shown a mean deviation of 3.08 degrees in angular position, 1.14 at the entry point, and 1.46 at apex position. Involved deviation factors were related to planning, laboratory, and surgical phases. CONCLUSION: Guided surgery may have a limited precision as technique, which surgeons need to be aware in the planning process. This review suggests some security measures in guided surgery process.

Implant placement for patients with cleft lip and palate: A clinical report and guidelines for treatment.

The multidisciplinary teams involved in the treatment of individuals with cleft lip and palate are challenged when implants are indicated in the cleft area. Difficulties include obtaining a healthy peri-implant area and, especially, obtaining the natural-looking papilla essential for esthetic success. The area affected by the cleft has a bone deficiency, which is typically augmented with an alveolar bone graft at adolescence. Guidelines for the 3-dimensional placement of implants at the cleft area are presented based on clinical reports. The patients were followed up for at least 1 year. Adoption of the proposed guidelines enables satisfactory esthetic and functional outcomes in patients with cleft lip and palate.

Dental implant register: Summary and consensus statements of group 2. The 5th EAO Consensus Conference 2018.

OBJECTIVES: This publication reports the EAO Workshop group-2 and consensus plenary discussions and statements on a narrative review providing the background and possible facilities and importance of a dental implant register, to allow for a systematic follow-up of the clinical outcome of dental implant treatment in various clinical settings. It should be observed that the format of the review and the subsequent consensus report consciously departs from conventional consensus publications and reports. MATERIAL AND METHODS: The publication was a narrative review on the presence and significance of quality registers regarding select medical conditions and procedures. The group discussed and evaluated the publication and made corrections and recommendations to the authors and agreed on the statements and recommendations described in this consensus report. RESULTS: Possible registrations to be included in an implant register were discussed and agreed as a preliminary basis for further development, meaning that additional parameters be included or some be deleted. CONCLUSIONS: It was agreed to bring the idea of an implant quality register, including the presented results of discussions and proposals by the group- and plenary sessions, to the EAO Board for further discussion and decision.

Dental Implant Quality Register-A possible tool to further improve implant treatment and outcome.

The Board of EAO (European Association for Osseointegration) has discussed an initiative to explore the conditions to establish a Dental Implant Register. It was suggested to bring this issue to the EAO Consensus Conference 2018 for a discussion and to possibly propose relevant and manageable parameters. This article presents some select examples from quality registers in the medical field. Based on the experience of established registers, essentially in the medical field, factors considered to be of importance, if and when establishing a Dental Implant Register are introduced and discussed.

Guidelines for development of Implant Dentistry in the next 10 years regarding innovation, education, certification, and associations.

BACKGROUND: During the third Summer Camp of European Association of Osseointegration (EAO), 40 junior representatives from various European societies and associations were brought together to discuss and explore the following topics in Implant Dentistry in the next 10 years: (I) certification, (II) societies and associations, (III) continuing education, and (IV) innovations. AIMS: The aims of all working groups were to identify and outline the present situation in the area of the selected topic and to propose improvements and innovations to be implemented in the following 10 years. MATERIALS AND METHODS: Four different groups were assigned randomly to one of the four working units. The method to discuss the selected topics was World Cafè. The summaries of four topics were then given to all participants for peer review. RESULTS AND CONCLUSIONS: All four groups presented the conclusions and guidelines accordingly: (I) The recognition for Implant Dentistry and accreditation of training programs would lead to an improvement of the quality of care to the benefit of the patients; (II) Dental associations and societies have to continuously improve communication to meet needs of dental students, professionals, and patients (III) European Dental Board should be installed and become responsible for continue dental education; (IV) dental engineering, peri-implant diseases, and digital workflow in dentistry currently have limited tools that do not guarantee predictable results.

Group 2 ITI Consensus Report: Prosthodontics and implant dentistry.

OBJECTIVES: Working Group 2 was convened to address topics relevant to prosthodontics and dental implants. Systematic reviews were developed according to focused questions addressing (a) the number of implants required to support fixed full-arch restorations, (b) the influence of intentionally tilted implants compared to axial positioned implants when supporting fixed dental prostheses (FDPs), (c) implant placement and loading protocols, (d) zirconia dental implants, (e) zirconia and metal ceramic implant supported single crowns and (f) zirconia and metal ceramic implant supported FDPs. MATERIALS AND METHODS: Group 2 considered and discussed information gathered in six systematic reviews. Group participants discussed statements developed by the authors and developed consensus. The group developed and found consensus for clinical recommendations based on both the statements and the experience of the group. The consensus statements and clinical recommendations were presented to the plenary (gathering of all conference attendees) and discussed. Final versions were developed after consensus was reached. RESULTS: A total of 27 consensus statements were developed from the systematic reviews. Additionally, the group developed 24 clinical recommendations based on the combined expertise of the participants and the developed consensus statements. CONCLUSIONS: The literature supports the use of various implant numbers to support full-arch fixed prostheses. The use of intentionally tilted dental implants is indicated when appropriate conditions exist. Implant placement and loading protocols should be considered together when planning and treating patients. One-piece zirconia dental implants can be recommended when appropriate clinical conditions exist although two-piece zirconia implants should be used with caution as a result of insufficient data. Clinical performance of zirconia and metal ceramic single implant supported crowns is similar and each demonstrates significant, though different, complications. Zirconia ceramic FDPs are less reliable than metal ceramic. Implant supported monolithic zirconia prostheses may be a future option with more supporting evidence.

Biomechanical aspects: Summary and consensus statements of group 4. The 5th EAO Consensus Conference 2018.

OBJECTIVES: The aim of the present publication was to report on the EAO Workshop group-4 discussions and consensus statements on the five reviews previously prepared. These reviews provided the scientific evidence on the effect of crown-to-implant ratio, on reconstructions with cantilevers in fully and partially edentulous patients, on biological and technical complications of tilted in comparison with straight implants, and on the effects of osseointegrated implants functioning in a residual dentition. MATERIAL AND METHODS: The group discussed, evaluated, corrected where deemed appropriate, and made recommendations to the authors regarding the following five reviews submitted: (a) Is there an effect of crown-to-implant ratio on implant treatment outcomes?; (b) Implant-supported cantilevered fixed dental rehabilitations in fully edentulous patients; (c) and in partially edentulous patients; (d) Biological and technical complications of tilted implants in comparison with straight implants supporting fixed dental prostheses; (e) What are the adverse effects of osseointegrated implants functioning among natural teeth of a residual dentition? Based on the five manuscripts and the discussion among the group as well as the plenum members, the major findings were summarized, consensus statements were formulated, clinical recommendations were proposed, and areas of future research were identified. RESULTS: Crown-to-implant ratios ranging from 0.9 to 2.2 did not influence the occurrence of biological or technical complications also in single-tooth restorations. Reconstructions with cantilevers for the rehabilitation of fully and partially edentulous jaws showed high implant and reconstruction survival rates. In contrast, the rate of complications-in particular associated with veneering material-was high during the observation period of 5-10 years. The data reported were primarily derived from studies with high risk of bias. The data for single-implant reconstructions were small. There was no evidence that distally tilted implants were associated with higher failure rates and increased amounts of marginal bone loss. The data supporting these findings, however, were at high risk of bias and frequently incompletely reported. Frequent positional changes occurred between the natural teeth and the implant-supported restorations. These changes were more pronounced in younger individuals, and even though they were reduced with age, they still occurred in adult patients. Even though these changes were frequent, potential implications for the patient are unclear. CONCLUSIONS: The use of single-tooth restorations with crown-to-implant ratio in between 0.9 and 2.2 may be considered a viable treatment option. Multiunit reconstructions with cantilevers are a viable treatment option in fully and partially edentulous patients. Clinicians and patients should be aware, however, that complications are frequent and primarily related to resin material used for veneering. There is some evidence that tilting an implant does affect stability of the implant and the surrounding bone. Treatment options to tilted implants should carefully be considered, as the effect on soft tissues and on prosthesis behavior is poorly reported for tilted implants. Positional changes in the dentition in relation to implant-supported restorations occur frequently. The patient should be informed about the possible need for a treatment related to these changes in the long term.

A multiscale analytical approach to evaluate osseointegration.

Osseointegrated implants are frequently used in reconstructive surgery, both in the dental and orthopedic field, restoring physical function and improving the quality of life for the patients. The bone anchorage is typically evaluated at micrometer resolution, while bone tissue is a dynamic composite material composed of nanoscale collagen fibrils and apatite crystals, with defined hierarchical levels at different length scales. In order to understand the bone formation and the ultrastructure of the interfacial tissue, analytical strategies needs to be implemented enabling multiscale and multimodal analyses of the intact interface. This paper describes a sample preparation route for successive analyses allowing assessment of the different hierarchical levels of interest, going from macro to nano scale and could be implemented on single samples. Examples of resulting analyses of different techniques on one type of implant surface is given, with emphasis on correlating the length scale between the different techniques. The bone-implant interface shows an intimate contact between mineralized collagen bundles and the outermost surface of the oxide layer, while bone mineral is found in the nanoscale surface features creating a functionally graded interface. Osteocytes exhibit a direct contact with the implant surface via canaliculi that house their dendritic processes. Blood vessels are frequently found in close proximity to the implant surface either within the mineralized bone matrix or at regions of remodeling.

Factors Affecting Dental Implant Stability Measured Using the Ostell Mentor Device: A Systematic Review.

OBJECTIVES: The aim of this study was to review the literature on factors that may affect dental implant stability as measured with the Ostell mentor device. MATERIALS AND METHODS: A systematic search of the literature was performed in Pubmed, Scopus, and Cochrane databases using dental implants, stability, and resonance frequency analysis as key words. RESULTS: The most relevant randomized controlled trials and clinical trials (n = 39) were selected from among 264 articles. CONCLUSIONS: Many factors can affect dental implant stability as measured with the Ostell mentor device. This may be a useful instrument for deciding the timing of implant loading, but additional research is required to establish the reliability and predictability of resonance frequency analysis for the future osseointegration of dental implants, which remains controversial.

A Comparative Study of Stability After the Installation of 2 Different Surface Types of Implants in the Maxillae of Dogs.

PURPOSE: This study was performed to investigate the histologic and histomorphometric findings of 2 different types of implant. MATERIALS AND METHODS: Resorbable blasting media (RBM) and sandblasted with larger grit and acid etched (SLA) surfaced implants (24 fixtures in each group) were installed in posterior maxilla of dogs. The initial stability was measured using Periotest (Periotest value [PTV]). After 6 or 12 weeks, fixtures with surrounding bone were harvested. RESULTS: The average initial stability of the SLA group (-1.71 ± 2.9) was higher than that of the RBM group (-1.25 ± 3.21), but there was no significant difference. The mean PTV of the RBM surface was higher than the SLA surface at 12 weeks. The average bone-implant contacts were 67.6% ± 16.0% at 6 weeks and 82.7% ± 8.6% at 12 weeks in the SLA group and 69.9% ± 17.6% at 6 weeks and 78.3% ± 9.2% at 12 weeks in the RBM group. CONCLUSION: The SLA and resorbable blasting media (RBM) surface implants demonstrated good stabilities and healing processes of the surrounding bone in the posterior maxilla. Therefore, the two domestic implants could provide predictable clinical results.

Relationship Between Insertion Torque and Resonance Frequency Measurements, Performed by Resonance Frequency Analysis, in Micromobility of Dental Implants: An In Vitro Study.

PURPOSE: To evaluate the micromobility of dental implants under occlusal loading in relation to stability measurements of resonance frequency analysis and insertion torque. MATERIALS AND METHODS: The sample comprised of 24 implants inserted in 12 fresh cow ribs. Insertion torque and Osstell implant stability quotient (ISQ) measurements were recorded. An "ad hoc" acrylic premolar was made on a temporary abutment and screwed to each implant, and a force of 100 N was subsequently applied at an angle of 6 degrees. Implant micromotion was measured using a Questar microscope with a resolution of 2 µm and an image analysis program. RESULTS: Data show a statistically significant inverse correlation between the ISQ values and implant micromotion under a load of 100 N (R = 0.86, P < 0.0001). The same relationship is found between insertion torque and implant micromotion, although the relationship is linear up to 34 N·cm and becomes exponential for higher values (R = 0.78, P < 0.0001). A direct correlation is established between insertion torque and ISQ values. CONCLUSION: There is an inverse relationship between both ISQ and insertion torque values and implant micromotion under a load of 100 N.

Retrospective long-term evaluation of dental implants in totally and partially edentulous patients: part II: periimplant disease.

PURPOSE: This retrospective longitudinal study aims to assess long-term outcomes of osseointegrated dental implants placed in partially and totally edentulous patients. MATERIAL AND METHODS: Patients who were willing to sign the informed consent and attend a check-up were included. The prevalence of periimplant disease was calculated. Cases were further divided into mucositis or periimplantitis. Uni- and multi-variate statistical analyses were conducted to determine the influence of various factors. RESULTS: A total of 105 patients who had received 342 implants were included. Mean follow-up was 13.19 ± 3.70 years. The prevalence of periimplant disease was 14.2% of the analyzed implants and 21% of patients. An additional 4.8% of patients reported a previous presence of periimplant disease without current disease. The prevalence of mucositis and periimplantitis was 11.2% and 1.7%, respectively, of analyzed implants. Factors with possible influence on the presence of periimplant disease were gender, alcohol consumption, chemotherapy and/or head and neck radiotherapy, history of periodontal disease, and years of function. CONCLUSION: In our sample, periimplant disease was not infrequent, being present in 1 of 5 patients at the final check-up.

Guided surgery: accuracy and efficacy.

Different computer-assisted implant-placement procedures are currently available. These differ in software, template manufacture, guiding device, stabilization and fixation. The literature seems to indicate that one has to accept a certain inaccuracy of ±2.0 mm, which seems large initially but is clearly smaller than for nonguided surgery. A reduction of accuracy to below 0.5 mm seems extremely difficult. A common shortcoming identified in the studies included in this review is inconsistency in how clinical data and outcome variables are reported. Another limitation is the small number of comparative clinical studies. In order to find the best guiding system or the most important parameters for optimal accuracy, more randomized clinical trials are necessary. Information on cost-effectiveness and patient-centered evaluations (i.e. questionnaires and interviews) must also be included.

The precision of drill calibration for dynamic navigation.

OBJECTIVES: To quantify the reproducibility of the drill calibration process in dynamic navigation guided placement of dental implants and to identify the human factors that could affect the precision of this process in order to improve the overall implant placement accuracy. METHODS: A set of six drills and four implants were calibrated by three operators following the standard calibration process of NaviDent® (ClaroNav Inc.). The reproducibility of the position of each tip of a drill or implant was calculated in relation to the pre-planned implants' entry and apex positions. Intra- and inter-operator reliabilities were reported. The effects of the drill length and shape on the reproducibility of the calibration process were also investigated. The outcome measures for reproducibility were expressed in terms of variability range, average and maximum deviations from the mean distance. RESULTS: A satisfactory inter-rater reproducibility was noted. The precision of the calibration of the tip position in terms of variability range was between 0.3 and 3.7 mm. We noted a tendency towards a higher precision of the calibration process with longer drills. More calibration errors were observed when calibrating long zygomatic implants with non-locking adapters than with pointed drills. Flexible long-pointed drills had low calibration precision that was comparable to the non-flexible short-pointed drills. CONCLUSION: The clinicians should be aware of the calibration error associated with the dynamic navigation placement of dental and zygomatic implants. This should be taken in consideration especially for long implants, short drills, and long drills that have some degree of flexibility. CLINICAL SIGNIFICANCE: Dynamic navigation procedures are associated with an inherent drill calibration error. The manual stability during the calibration process is crucial in minimising this error. In addition, the clinician must never ignore the prescribed accuracy checking procedures after each calibration process.

Chief resident case experience and autonomy are associated with resident confidence and future practice plans.

PURPOSE: To measure oral and maxillofacial surgery (OMS) chief resident case experience, including autonomy, and discover the role of this experience in developing resident confidence and determining the scope of practice on completion of training. MATERIALS AND METHODS: A cross-sectional study was conducted using an online questionnaire made available to residents near the completion of their final year of training in United States OMS training programs. Predictors were the case numbers and autonomy level. Outcomes were the anticipated frequency of practice, confidence to meet the standard of care, and changes in anticipated practice scope. Each was measured in 10 domains within the scope of OMS. RESULTS: Eighty-four residents (44%) completed the 116-item questionnaire. All respondents were "very confident" in their ability to meet the standard of care in mandibular trauma and dentoalveolar surgery. Autonomy was associated with the confidence to meet the standard of care in midface trauma, temporomandibular joint, orthognathic, cosmetic, pathology, reconstructive, and craniofacial surgery. Associations were noted between primary surgeon cases and confidence in midface trauma, temporomandibular joint, orthognathic, cosmetic, and craniofacial surgery. Case numbers were associated with an anticipated frequency of practice within the domains of midface trauma, temporomandibular joint, cosmetic, and pathology surgery. CONCLUSIONS: Results of this study suggest an association between a resident's surgical case experience (overall exposure and autonomy) and that resident's future plans for practice and confidence to meet the standard of care in this specialty. OMS training curricula should evolve to incorporate an evaluation of competence and an appropriate transfer of responsibility and experience to residents, thus maximizing confidence and future practice opportunities.

A comparative study of the Osstell™ versus the Osstell Mentor™ to evaluate implant stability in human cadaver mandibles.

The aim of this study was to assess the primary stability of dental implants by resonance frequency analysis (RFA) using the Osstell™ and Osstell Mentor™ devices and to investigate the reproducibility and comparability of the results obtained with these devices. Twenty-four Straumann implants (Straumann AG, Basel, Switzerland) were placed in the anterior mandible of 12 fresh edentulous human cadaver mandibles. The implant stability quotients (ISQs) were measured with the Osstell™ and Osstell Mentor™ when implants were inserted at 50% of their length and following their complete insertion. The Osstell™ device measured lower scores compared with the Osstell Mentor™. This was significant for the full position (mean difference = 9·9), t (11) = 7·4, P < 0·001 and for the halfway position (mean difference = 5·9), t (11) = 2·41, P = 0·03. In conclusion, the Osstell™ produced relatively lower ISQ scores than the Osstell Mentor™.

Impact of operator experience on the accuracy of implant placement with stereolithographic surgical templates: an in vitro study.

STATEMENT OF PROBLEM: To achieve functional and esthetic results, implants must be placed accurately. However, little information relating to the effect of operator experience on implant placement accuracy is available. PURPOSE: The objective of this investigation was to measure the accuracy of dental implant placement with a bone-supported stereolithographic surgical template created from a virtual implant plan and to determine the effect of operator experience on implant placement accuracy. MATERIAL AND METHODS: Twenty photopolymer resin edentulous mandibles were scanned with cone beam computerized tomography (CBCT). Five implants were planned virtually for each mandible, and a stereolithographic surgical template was made. Four operators placed a total of 100 implants (25 per operator). Two of the operators were experienced in implant placement and 2 operators had limited prior implant placement experience. A CBCT scan of the postimplant placement mandibles was performed, and the images were superimposed on the preimplant placement images containing the virtual implant plans. The amount of angular, horizontal, and vertical deviation of the placed implants from the virtually planned implants at the apex and platform was calculated, and statistically significant differences were detected between the operator groups by using a multivariate analysis of variance (MANOVA) (α=.05). RESULTS: For the experienced operators, the mean error of angular deviation was 2.60 ±1.25 degrees, of horizontal deviation at the apex 0.34 ±0.15 mm, of horizontal deviation at the platform 0.63 ±0.28 mm, of vertical deviation at the apex 0.59 ±0.12 mm, and of vertical deviation at the platform 0.16 ±0.11 mm. For the inexperienced group, the mean error of angular deviation was 3.96 ±1.64 degrees, of horizontal deviation at the apex 0.42 ±0.19 mm, of horizontal deviation at the platform 0.77 ±0.33 mm, of vertical deviation at the apex 0.62 ±0.13 mm, and of vertical deviation at the platform 0.15 ±0.11 mm. The MANOVA showed a statistically significant difference between the experienced and inexperienced groups for angular and horizontal error at the implant apex and platform (P<.05). CONCLUSIONS: The results of this in vitro investigation revealed that the experience level of the operator placing the implants contributes to the accuracy of implant placement, with more experienced operators placing more implants accurately.

Cortical bone thickness of the alveolar process measured with cone-beam computed tomography in patients with different facial types.

INTRODUCTION: The purpose of this study was to determine the cortical bone thickness of the alveolar process in the maxilla and the mandible on cone-beam computed tomographs of adults with low, normal, and increased facial heights. METHODS: This study was conducted on 155 images of adult patients (20-45 years old) who were assigned to the low-angle, normal, and high-angle groups. The thickness of the buccal cortical plates of the maxilla and the mandible, and the palatal cortical plates of the maxilla, were measured. RESULTS: There was no statistically significant difference between the groups regarding mean ages, sex, and sagittal facial types. High-angle patients had significantly lower values than did low-angle patients in all mini-implant insertion sites in both the maxillary and mandibular alveolar bones. The mandibular and maxillary buccal measurements showed a similar pattern; the lowest values were for the high-angle group, followed by the normal group; the highest values were measured in the low-angle patients. CONCLUSIONS: Clinicians should be aware of the probability of thin cortical bone plates and the risk of mini-implant failures at maxillary buccal alveolar mini-implant sites in high-angle patients, and at mandibular buccal alveolar mini-implant sites between the canine and the first premolar in normal and high-angle patients.

The effect of angulation sensors on implant placement.

It is hypothesized that use of an angulation sensor could increase the alignment accuracy of multiple implant osteotomies without requiring the use of guided-surgical templates. Therefore, the purpose of this study was to determine if use of such a sensor mounted on a surgical handpiece could improve implant placement.