Accuracy comparison of guided surgery for dental implants according to the tissue of support: a systematic review and meta-analysis

The Accuracy of Immediate Implantation Guided by Digital Templates and Potential Influencing Factors: A Systematic Review

BACKGROUND

Immediate implantation guided by digital templates has drawn a great attention in the aesthetic zone, while the accuracy of immediate implantation guided by digital templates has yielded mixed results and many potential factors are known to affect its accuracy. The purpose of our systematic review was to evaluate the accuracy of implant placement guided by the digital template and summarizing its potentials influencing factors.

MATERIALS AND METHODS

We conducted an electronic search of publications upto July 2023, using PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science to identify studies on accuracy of immediate implant placement surgery guided by digital templates. We selected cohort studies (prospective and retrospective studies) and randomized controlled trials (RCTs). The primary outcome was accuracy of immediate implant placement surgery guided by digital templates.

RESULTS

Seven studies in total fulfilled the inclusion criteria, comprising two prospective studies and five retrospective studies. We collected data including names of authors, publication period, study design, total sample size, clinical conditionas, planning/preoperative details, surgical procedure information, and evaluation criteria. Average global coronal deviation, apical deviation, depth deviation and angular deviation were respectively 0.74 mm (95% confidence interval [CI] 0.41-1.08, I2 = 99.0%), 1.01 mm (95% CI 0.83-1.20, I2 = 94.0%), 0.50 mm (95% CI 0.36-0.65, I2 = 75.3%) and 2.34° (95% CI 1.68-3.00, I2 = 94.5%). The quality assessment was conducted at a medium to high level.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Our systematic review demonstrates that immediate implantation guided by digital templates generally achieves acceptable accuracy. Factors influencing accuracy include the type of surgical guide, method of guide fabrication, surgical protocols, anatomical variability, and preoperative planning challenges. To improve clinical application, it is crucial to enhance the reporting of patient-centred outcomes and socioeconomic benefits.

Accuracy of markerless registration methods of DICOM and STL files used for computerized surgical guides in mandibles with metal restorations: An in vitro study

STATEMENT OF PROBLEM

Digital imaging and communications in medicine (DICOM) files together with surface scans must be accurately registered in virtual implant planning software programs to match real-life dimensions and ensure correct plan transfer through computer-aided manufactured surgical guides.

PURPOSE

The purpose of this in vitro study was to evaluate the accuracy of 3 different registration methods of DICOM data with and without metal restorations and a metal artifact reduction (MAR) tool for surface scans.

MATERIAL AND METHODS

Thirteen dentate mandibles were assigned to each group of this study (n=39). Baseplate wax was adapted to the bone surfaces of each mandible, and 5 radiopaque markers were attached. A desktop scanner was used to obtain control scans. The groups of metal-free mandibles (MFM) and mandibles with metal restorations (MRM) were scanned to obtain DICOM data without a MAR tool. Additional DICOM data for the MRM were obtained with the MAR tool (MRM-MAR). Point-based registration (PBR), best-fit registration (BFR), and automatic registration (AR) were used to align standard tessellation language (STL) and DICOM data, and 3 data sets were exported. Radiographic markers on each data set were compared with those on the control scan, and positional deviations were calculated and statistically evaluated with 1-way ANOVA followed by multiple pairwise comparisons, independent samples t test, and 2-way ANOVA (α=.05).

RESULTS

Within each group, PBR had the lowest deviation values with statistical significance in the MFM and the MRM-MAR groups (P<.001). AR showed failure in the MRM and the MRM-MAR groups. Statistically significant differences were found on comparing the average deviations among the 3 groups for PBR only (P<.001). No association was found between deviation values and the presence or absence of metal restoration, while a positive association was found with the type of registration method (P<.001).

CONCLUSIONS

PBR had the highest accuracy level compared with AR and BFR methods. An increase in the number of calculations resulted in more deviation values. The MAR tool had a positive effect on PBR in mandibles with metal restorations.

[Anatomy and function of the canalis sinuosus and its injury prevention and treatment strategies in implant surgery]

The canalis sinuosus, a canal containing the anterior superior alveolar nerve bundle, originates from the infraorbital canal and extends along the maxillary sinus and nasal cavity edges to the anterior maxilla. It was once regarded as an anatomical variation. However, with the widespread application of cone beam computed tomography (CBCT), the detection rate of canalis sinuosus in the population has increased. The canalis sinuosus exhibits diverse courses, branching into multiple accessory canals and terminating at the nasal floor or the anterior tooth region, with the majority traversing the palatal side of the central incisor. The anterior superior alveolar nerve bundle within the canalis sinuosus not only innervates and nourishes the maxillary anterior teeth and the corresponding soft tissues, and the maxillary sinus mucosa, but also relates to the nasal septum, lateral nasal wall, and parts of the palatal mucosa. To minimize surgical complications, strategies for preventing and treating canalis sinuosus injuries need to be investigated. Preoperatively, CBCT is used to identify the canalis sinuosus and to virtually design implant placement at a distance of more than 2 mm from the canalis sinuosus. Intraoperatively, assessing bleeding and patient comfort, complemented by precision surgical techniques such as the use of implant surgical guide plates. Postoperatively, CBCT is used to examine the relationship between the implant and the canalis sinuosus, and treatment of canalis sinuosus injuries can be tailored based on the patient's symptoms. This review summarizes the detection of canalis sinuosus in the population, its anatomical characteristics, and the physiological functions in the anterior maxilla, and discusses strategies for avoiding canalis sinuosus injuries during implant surgery, thereby enhancing clinical awareness and providing references for clinical decision-making.

Are Sleeves Necessary in Static Computer-Assisted Implant Surgery? A Comparative In Vitro Analysis

OBJECTIVES

This study aims to examine differences in trueness and precision between surgical guides with (S) and without sleeves (SL). A secondary aim was to assess the impact of the sleeve-to-bone distance.

MATERIALS AND METHODS

Mandible replicas (n = 120) were printed from an STL file obtained from a clinical CBCT. The mandibles were divided into sleeved (S, n = 60) and sleeveless (SL, n = 60) groups, each further divided into three categories (n = 20 each) with different heights from the guide to the implant platform: 2 mm (H2), 4 mm (H4), or 6 mm (H6). Digital planning and surgical guide design were done for a 4.1 × 10 mm implant for site #30. Post-op positions were captured using a scan body and lab scanner. Angular deviation was the primary outcome, with 3D and 2D deviations as secondary parameters. Statistical analysis included two-sample t-tests, and one-way and two-way ANOVA.

RESULTS

Group S (2.41 ± 1.41°) had significantly greater angular deviation than Group SL (1.65 ± 0.93°; p = 0.0001). Angular deviation increased with sleeve-to-bone distance. H2 deviations were 1.48 ± 0.80° (S) vs. 1.02 ± 0.45° (SL; p < 0.05), H4: 2.36 ± 1.04° (S) vs. 1.48 ± 0.79° (SL; p < 0.05), H6: 3.37 ± 0.67° (S) vs. 2.46 ± 0.89° (SL; p < 0.05). 3D deviation at the implant platform was 0.36 ± 0.17 mm (S) vs. 0.30 ± 0.15 mm (SL; p < 0.05) and at the apex 0.74 ± 0.34 mm (S) vs. 0.53 ± 0.31 mm (SL; p < 0.01). Group SL at H2 had the smallest inter-implant distance (0.53 ± 0.37°), while Group S at H4 had the largest (1.20 ± 0.84°; p < 0.05).

CONCLUSIONS

Sleeveless guides are more accurate than sleeved guides, and angular deviation is influenced by the distance from the guide to the implant platform.

Accuracy of navigation guided implant surgery for immediate loading complete arch restorations: Prospective clinical trial

OBJECTIVES

To assess navigation accuracy for complete-arch implant placement with immediate loading of digitally prefabricated provisional.

MATERIALS AND METHODS

Consecutive edentulous and terminal dentition patients requiring at least one complete-arch FDP were treated between December 2020 and January 2022. Accuracy was evaluated by superimposing pre-operative and post-operative cone beam computed tomography (CBCT), recording linear (mm) and angular (degrees) deviations. T-tests were performed to investigate the potential effect of the registration algorithm (fiducial-based vs. fiducial-free), type of references for the fiducial-free algorithm (teeth vs. bone screws), site characteristic (healed vs. post-extractive), implant angulation (axial vs. tilted), type of arch (maxilla vs. mandible) on the accuracy with p-value <0.05.

RESULTS

Twenty-five patients, 36 complete-arches, and 161 implants were placed. The overall mean angular deviation was 2.19° (SD 1.26°). The global platform and apex mean deviations were 1.17 mm (SD 0.57 mm), and 1.30 mm (SD 0.62 mm). Meaningful global platform (p = 0.0009) and apical (p = 0.0109) deviations were experienced only between healed and post-extraction sites. None of the analyzed variables significantly influenced angular deviation. Minor single-axis deviations were reported for the type of jaw (y-axis at implant platform and apex), registration algorithm (y-axis platform and z-axis deviations), and type of references for the fiducial-free algorithm. No statistically significant differences were found in relation to implant angulation.

CONCLUSIONS

Within the study limitations navigation was reliable for complete-arch implant placement with immediate loading digitally pre-fabricated FDP. AI-driven surface anatomy identification and calibration protocol made fiducial-free registration as accurate as fiducial-based, teeth and bone screws equal as references. Implant site characteristics were the only statistically significant variable with healed sites reporting higher accuracy compared to post-extractive. Live-tracked navigation surgery enhanced operator performance and accuracy regardless of implant angulation and type of jaw. A mean safety room of about 1 mm and 2° should be considered.

Accuracy of dental implants positioning in computer-assisted surgeries: In vitro study

OBJECTIVES

The aim of this study is to presents an experimental method for surgical guide confection using an intraoral scanner to obtain a 3D model of the patient's complete denture and compare its accuracy with the conventional methodology using computed tomography.

STUDY DESIGN

This prospective in-vitro study used 30 polyurethane pre-manufactured mandibles which were divided into two groups, conventional technique (group I) and a new method using intraoral scanner (group II), establishing the virtually planned position of the dental implants as a control group, considered as the gold standard for postoperative comparison.

RESULTS

The difference between these methods is close to zero and not statistically significant (p > 0.05), being heigh deviation (Xh) with p:0.130 and angulation difference of dental implants between the groups (Ang) with p:0.396.

CONCLUSION

The acquisition of stereolithography image of the prosthesis using an intraoral scanner has a clinically acceptable accuracy, being in agreement with the conventional method.

Comparison of the accuracy of implant placement using a simple guide device and freehand surgery

Background/purpose

In clinical settings, there may be a need for a guide device that is simple and enhances the positioning accuracy of prosthetics. This study aimed to compare the accuracy of implant positioning using two methods: implant placement with a simple guide device (SGD) and freehand surgery.

Materials and methods

A total of 103 patients were randomly assigned to the control or study group. In the control group, implant placement was performed using the freehand technique. In the study group, implant placement was conducted with an SGD. Implant positioning accuracy was assessed by measuring how much the central position, fixture angulation, and fixture position differed from the ideal implant position based on periapical radiographs and cone-beam computed tomography images. In patients with double implants, parallelism between the two fixtures was also measured.

Results

There were 124 subjects, with 84 having single implants (42 in the control group and 42 in the study group) and 40 having double implants (20 in the control group and 20 in the study group). Utilization of the SGD for both single and double implant placement improved the accuracy of the central position, fixture angulation, and fixture position (P < 0.05). Additionally, in double implantation cases, it significantly enhanced parallelism between the two fixtures (P < 0.001).

Conclusion

These findings suggest that use of an SGD leads to more accurate implant placement compared with freehand surgery taking into account the final prosthetic restoration.

Knowledge structure and research hotspots on digital scanning for implant-supported complete-arch prosthesis: A bibliometric analysis

Background

Digital scanning is increasingly widely used for implant-supported complete-arch prosthese. However, a quantitative literature analysis is lacking for this field. This study aims to conduct a bibliometric analysis to summarize the knowledge structure and research hotspots of digital scanning for implant-supported complete-arch prosthesis.

Materials and methods

Relevant articles and reviews, published between 1994 and 2023, were obtained from the Web of Science Core Collection (WoSCC). Indicators such as publication count, annual growth, citation count, co-citation count, impact factor, Journal citation reports (JCR) division, H-index are used to assess the contribution of countries, journals, authors or the quality of articles. Visual maps, cluster analysis and keyword cloud are used to evaluate the cooperation pattern and topic trends.

Results

580 eligible publications, including 555 articles and 25 reviews, were analyzed. The United States is the leading country in this area, received the most citations. The Journal of Prosthetic Dentistry is the scientific journal with the highest impact. The analysis of keywords and ongoing trials shows that the accuracy of relevant techniques is a current hot topic in this field.

Conclusion

In recent years, digital scanning technique for implant-supported complete-arch prosthesis has made rapid progress. By reviewing the published literature, we found the United States is the global leader in the field of digital scanning for complete-arch implant prosthesis. Accuracy is the core word in this field, more scientific evidence is needed to support the clinical application of digital scanning in this field.

A method for assessing guide layout and error on implant accuracy

Functional and esthetic results require accurate implant placement. We aimed to develop a predictive method for assessing guide layout and error on implant accuracy. A mathematical model for position error analysis was constructed based on triangular mesh data. This model examines the relationship between the spatial shifts of multiple surfaces and the spatial shifts of specific points. It involves encasing these surfaces in a cuboid bounding box and expressing them in a local coordinate system. The influence of positioning surface error and layout of surgical guide were researched with a simulation test. The result shows that error in the implant site position is directly related to the error in the guide locating surface under the same layout. When the guide locating surface layout varies, as the length, width, and height of the minimum cuboid envelope increase, the maximum deviation in the implant site position decreases.

Accuracy of Implant Guided Surgery in Fully Edentulous Patients: Prediction vs. Actual Outcome-Systematic Review

Objectives: Examine deviations between the digitally planned and actual implant positions in clinical studies using static fully guided surgical guides. Identify potential associated factors and strategies to minimize their likelihood. Materials and Methods: This systematic review was conducted following the PRISMA checklist. The literature search was conducted in the PubMed® and Scopus® databases up to February 2024 following the PICOS search strategy. Clinical trials conducted between 2013 and 2024, evaluating the accuracy of static fully guided surgical guides placed in fully edentulous patients, were included. The studies had to assess at least two of the following parameters: angular deviation, cervical deviation, apical deviation, and depth deviation. Results: Out of the 298 articles initially searched, six randomized clinical trials and three clinical trials were included. All but one article used mucosa-supported guides; the remaining one used bone-supported guides. Apical deviations were more significant than cervical deviations, and implants tended to be placed too superficially. The greatest mean deviations were 2.01 ± 0.77 mm for cervical and 2.41 ± 1.45 mm for apical deviations, with the largest angular deviation recorded at 4.98 ± 2.16°. Conclusions: The accuracy of the surgical guide is influenced by various factors, including the technique of image acquisition and subsequent planning, guide support methods, and the adopted surgical protocol. Apical deviations are influenced by cervical and angular deviations. Additionally, deviations were more pronounced in the mandible. Further studies with similar methodologies are necessary for a more precise assessment of the different factors and for establishing safety margins.

Autoclaving-induced dimensional changes of three-dimensional printed surgical guides: An in vitro study

OBJECTIVES

Surgical guides are frequently used for dental implant placement. The aim of this study was to evaluate the impact of the 3D printing process itself and subsequent steam autoclaving on the dimensional stability of five different resin/printer combinations (RPCs).

MATERIALS AND METHODS

Fifty identical surgical guides (10 per group) were produced consisting of five RPCs. Half of the guides (5 per group) were steam autoclaved with cycle 1 (121°C, 1 bar, 20.5 min) and the other half with cycle 2 (134°C, 2 bar, 5.5 min). All guides were scanned with a structured-light (SL) 3D scanner before (T0) and after (T1) autoclaving. Linear measurements along the x-, y-, and z-axes were performed at landmarks on the original STL file and on SL scans at T0 and T1, respectively. Wilcoxon signed-rank test, Kruskal-Wallis test, and linear mixed-effects models were performed, depending on the analysis.

RESULTS

Three-dimensional printing was associated with significant dimensional alterations for all RPCs. Steam autoclaving using cycle 1 was associated with significant shrinkage in x- (1 RPC), y- (2 RPCs), and z-direction (2 RPCs), while cycle 2 was also associated with shrinkage in x- (2 RPCs), y- (1 RPC), and z-direction (1 RPC). One resin did not present any dimensional changes independently of the cycle.

CONCLUSIONS

The majority of the guides presented minor but significant shrinkage due to 3D printing itself and both steam autoclaving cycles, the extent varied between different RPCs. Whether these changes compromise implant placement accuracy remains to be investigated.

Computer-assisted and robotic implant surgery: Assessing the outcome measures of accuracy and educational implications

OBJECTIVE

This scoping review aimed to (1) critically evaluate the outcomes measures used to assess the accuracy of implant placement with Computer Assisted Implant Surgery (CAIS) and (2) review the evidence supporting the efficient implementation of CAIS in training and education of clinicians.

METHODS

A scoping literature review was conducted aiming to identify (a) clinical trials assessing accuracy of implant placement with CAIS, and (b) clinical trials or simulation/cadaver studies where CAIS was utilised and assessed for the training/education of clinicians. Studies since 1995 were assessed for suitability and data related to the outcomes measures of accuracy and educational efficacy were extracted and synthesised.

RESULTS

Accuracy of CAIS has been mainly assessed through surrogate measures. Individual clinical trials have not shown any difference between static and dynamic CAIS, but recent meta-analyses suggest an advantage of dynamic CAIS in reducing angular deviation. The combination of static and dynamic CAIS might offer higher accuracy than each of the two used alone. Dynamic CAIS is suitable for novice surgeons and might even have added value as an education tool for implant surgery, although mastering the technique requires longer training than static.

CONCLUSION

Meta-analyses of large samples, new and diverse outcomes measures, as well as benchmarking of levels of accuracy with specific clinical outcomes will help to better understand the potential and limitations of CAIS. Dynamic CAIS is suitable for novice operators, but educational interventions distributed over longer periods of time will be required for mastery of the process.

The accuracy of implant placement using a combination of static and dynamic computer-assisted implant surgery in fully edentulous arches: A prospective controlled clinical study

OBJECTIVE

To compare the accuracy of implant position, using a combination of static and dynamic computer-assisted implant surgery (CAIS), with either static, dynamic, or freehand implant placement, in fully edentulous arches.

MATERIALS AND METHODS

Twenty-one patients with a total of 88 fixtures were included. Implants were divided equally into four groups: a combination of static and dynamic CAIS (SD group), static CAIS (S group), dynamic CAIS (D group), and freehand placement (FH group). Angular deviation, as well as the 3D platform and apex deviations, were measured for all groups. Furthermore, the direction of implant deviation was recorded and compared.

RESULTS

The FH group showed significantly more deviation compared to all groups, considering all the aspects, and at both the implant platform and apex. A significant difference in angular deviation between the SD and S groups (p < .001), and between the SD and D groups (p < .001) was noted, favoring the SD group. When evaluating implant distribution, the FH group showed a tendency towards the buccal, apical, and distal directions at platform and apex, while in the D group, implants shifted more to the buccal. In contrast, the SD group did not show a trend toward any specific direction. The S and SD groups did not show a statistical significance considering any direction.

CONCLUSIONS

The combination of static and dynamic CAIS increases the accuracy of implant placement in fully edentulous arches when compared with either static or dynamic CAIS alone, as well as freehand placement.

Accuracy of computer-guided implant surgery in partially edentulous patients: a prospective observational study

PURPOSE

This study aims to evaluate the amount of distortion using computer-guided implant surgery with 3D printed surgical guides in limited edentulous spaces.

MATERIALS AND METHODS

25 bone level self-tapping implants (Straumann® BL and BLT) were randomly inserted in either distal or intercalary posterior mandibular edentulism using a fully digital protocol and 3D printed surgical guides. Amount of inaccuracy was evaluated after superimposing the 3 coordinates of virtually planned and final implant images, which were obtained using intra-oral scans and scan bodies. Four evaluation parameters were considered: origo-displacement, error depth, apical displacement and angle between the planned and the placed implant.

RESULTS

The average of distortion was 0.71 mm for the origo-displacement, 0.36 mm for the error depth, 0.52 mm for the horizontal displacement and 3.34º for the error angle.

CONCLUSION

The major reason of exclusion was CBCT artifacts. Results of this study were aligned with the results of previous studies concerning partially edentulous spaces. CAD/CAM manufacturing process did not result in significant distortion whilst the biggest part of distortions originated from the surgical process. The learning curve in computer-guided implant surgery presented an important source of inaccuracy.

Advancements in computer-assisted orthognathic surgery: A comprehensive review and clinical application in South Korea

OBJECTIVES

Orthognathic surgery (OS) has evolved with technological advancements, notably through the implementation of computer-assisted orthognathic surgery (CAOS). This article aims to elucidate various types of CAOS and their efficiency and accuracy, supplemented by a thorough literature review focusing on their clinical applications in South Korea.

STUDY SELECTION, DATA, AND SOURCES

A comprehensive search strategy was employed, including systematic reviews, meta-analyses, randomized controlled trials, and observational studies published until December 2023 in the PubMed, MEDLINE, and Google Scholar databases. The literature search was limited to articles written in English.

RESULTS

Static CAOS demonstrated high precision, reduced operative time, and high accuracy, suggesting its potential reliability in orthognathic procedures. Dynamic CAOS presented a promising avenue for exploration, showing an accuracy comparable to that of traditional methods. The critical considerations for CAOS include accuracy, time efficiency, and cost-effectiveness. Recent studies have indicated advancements in the time efficiency of static CAOS. Static CAOS requires less equipment and is more cost-effective than dynamic CAOS.

CONCLUSIONS

CAOS offers clear advantages over conventional OS in terms of surgical convenience and accuracy in implementing the surgical plan. To achieve recognition as the gold standard method for maxillofacial deformity treatment, CAOS must overcome its limitations and undergo continuous verification via well-designed studies.

CLINICAL SIGNIFICANCE

The introduction of CAOS, mainly static CAOS with high precision and reduced surgical time, signifies a notable advancement in OS. However, rigorous studies are warranted to validate CAOS as the gold standard for treating maxillofacial deformities.

A Fully Guided Sequential Template Immediate Loading Protocol for Dual-Arch Implant Surgery

A method is described for designing, fabricating and implementing sequential template immediate loading protocols for dual arch implant therapy. A 41-year-old medically-free patient with terminal dentition was treated following stackable guide loading protocols for maxillary and mandibular arches. Implants were placed following extractions and immediately loaded with full arch fixed prostheses. Healing was uneventful and all implants integrated successfully. Special consideration was given to the design and clinical challenges when implementing stackable guide protocols for dual arch implant therapy.

Accuracy of dynamic navigation compared to static surgical guides and the freehand approach in implant placement: a prospective clinical study

BACKGROUND

Computer-guided implant surgery has improved the quality of implant treatment by facilitating the placement of implants in a more accurate manner. This study aimed to assess the accuracy of implant placement in a clinical setting using three techniques: dynamic navigation, static surgical guides, and freehand placement. We also investigated potential factors influencing accuracy to provide a comprehensive evaluation of each technique's advantages and disadvantages.

MATERIALS AND METHODS

Ninety-four implants in 65 patients were included in this prospective study. Patients were randomly assigned to one of three groups: dynamic navigation, static surgical guides, or freehand placement. Implants were placed using a prosthetically oriented digital implant planning approach, and postoperative CBCT scans were superimposed on preoperative plans to measure accuracy. Seven deviation values were calculated, including angular, platform, and apical deviations. Demographic and consistency analyses were performed, along with one-way ANOVA and post-hoc tests for deviation values.

RESULTS

The mean global platform, global apical, and angular deviations were 0.99 mm (SD 0.52), 1.14 mm (SD 0.56), and 3.66° (SD 1.64°) for the dynamic navigation group; 0.92 mm (SD 0.36), 1.06 mm (SD 0.47), and 2.52° (SD 1.18°) for the surgical guide group; and 1.36 mm (SD 0.62), 1.73 mm (SD 0.66), and 5.82° (SD 2.79°) for the freehand group. Both the dynamic navigation and surgical guide groups exhibited statistically significant differences in all values except depth deviations compared to the freehand group (p < 0.05), whereas only the angular deviation showed a significant difference between the dynamic navigation and surgical guide groups (p = 0.002).

CONCLUSION

Our findings highlight the superior accuracy and consistency of dynamic navigation and static surgical guides compared to freehand placement in implant surgery. Dynamic navigation offers precision and flexibility. However, it comes with cost and convenience considerations. Future research should focus on improving its practicality.

TRIAL REGISTRATION

This study was retrospectively registered at the Thai Clinical Trials Register-Medical Research Foundation of Thailand (MRF) with the TCTR identification number TCTR20230804001 on 04/08/2023. It was also conducted in accordance with the Declaration of Helsinki and approved by the institutional ethics committee at the Xian Jiaotong University Hospital of Stomatology, Xian, China (xjkqII[2021] No: 043). Written informed consent was obtained from all participants.

Accuracy of the novel digital non-cross-arch surgical guides with integration of tooth undercut retention and screw-bone support for implant placement in mandibular free-end

BACKGROUND

Large cross-arch free-end surgical guides can obscure the visual field, compromising surgical accuracy due to insufficient stability at the free-end. This in vitro study aims to evaluate the accuracy of novel digital non-cross-arch surgical guides designed for implant placement at the mandibular free-end, incorporating tooth undercut retention and screw-bone support.

MATERIALS AND METHODS

A mandibular dental model lacking left molars was utilized to fabricate unilateral (cross-arch) tooth-supported surgical guides (GT I, n = 20). Subsequently, two additional types of surgical guides were fabricated: GT II (covering two teeth, n = 20) and GT III (covering three teeth, n = 20). These novel surgical guides were designed to utilize the undercut of the supporting teeth for retention and enhance stability with screw-bone support at the guide's free-end. Furthermore, 60 identical guiding blocks were assembled on the three types of surgical guides to facilitate the implants' insertion. On a phantom head, 120 implant replicas were placed at the Federal Dentaire Internationale (FDI) teeth positions #36 and #37 on the dental model, employing a combination of surgical guides and guiding blocks. To assess accuracy, planned and placed implant positions were compared using intraoral optical scanning. Discrepancies in angulation and linear deviations, including the coronal/apical 3D deviations, lateral deviation as well as depth deviation, were measured. Statistical analysis was performed using two-way ANOVA and Bonferroni test (α = 0.05).

RESULTS

GT I exhibited significantly largest discrepancies, including angular and linear deviations at the crest and apex at every implant site. Especially in depth, at implant site #36, the mean deviation value of GT I (0.27 ± 0.13 mm) was twice as large as GT III (0.13 ± 0.07 mm), and almost twice as large as GT II (0.14 ± 0.08 mm). However, at implant site #37, this deviation increased to almost a five-fold relationship between GT I (0.63 ± 0.12 mm) and II (0.14 ± 0.09 mm), as well as between GT I and III (0.13 ± 0.09 mm). No significant discrepancies existed between the novel surgical guides at either implant site #36 or #37.

CONCLUSION

This study provides a practical protocol for enhancing accuracy of implant placement and reducing the size of free-end surgical guides used at mandibular molar sites.

An epidemiological qualitative/quantitative SWOT-AHP analysis in order to highlight the positive or critical aspects of dental implants: A pilot study

OBJECTIVES

In recent years, dental implants are increasing in popularity due to their high success rate, demonstrated functionality, and aesthetic treatment results. Scientific research is very active in proposing improvements in the quality and survival of implants, taking into consideration various aspects. The objective of this study was to provide a holistic epidemiologic view of the state of dental implants, using a systematic approach based on a multimethod SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis and AHP (analytical hierarchical process) qualitative-quantitative analysis to identify the characteristics that can determine their success or failure.

MATERIALS AND METHODS

The study used the hybrid method of SWOT-AHP.

RESULTS

Analysis of the results showed that among strengths, the skill of the dentist was considered the most important factor, followed by the success of dental implants in the old people; among weaknesses, bruxism and chronic diseases were highlighted; for opportunities, biomechanical behavior, in terms of good mechanical strength and good tribological resistance to chemical and physical agents in the oral cavity, were considered the most important factors; finally, among threats, medical liability and biomechanical problems had equal weight.

CONCLUSIONS

This study applied a multimethod SWOT-AHP approach to bring out favorable or critical evidence on the topic of dental implants. In accordance with the result of the strategic vector identified in the Twisting zone Adjustment type section, showed that implant surgery is a widespread technique but always needs improvement to increase the likelihood of success and reduce the complications that can lead to implant failure.

Influence of intraoral scanning coverage on the accuracy of digital implant impressions - An in vitro study

OBJECTIVES

To evaluate the influence of intraoral scanning coverage (IOSC) on digital implant impression accuracy in various partially edentulous situations and predict the optimal IOSC.

METHODS

Five types of resin models were fabricated, each simulating single or multiple tooth loss scenarios with inserted implants and scan bodies. IOSC was subgrouped to cover two, four, six, eight, ten, and twelve teeth, as well as full arch. Each group underwent ten scans. A desktop scanner served as the reference. Accuracy was evaluated by measuring the Root mean square error (RMSE) values of scan bodies. A convolutional neural network (CNN) was trained to predict the optimal IOSC with different edentulous situations. Statistical analysis was performed using one-way ANOVA and Tukey's test.

RESULTS

For single-tooth-missing situations, in anterior sites, significantly better accuracy was observed in groups with IOSC ranging from four teeth to full arch (p < 0.05). In premolar sites, IOSC spanning four to six teeth were more accurate (p < 0.05), while in molar sites, groups with IOSC encompassing two to eight teeth exhibited better accuracy (p < 0.05). For multiple-teeth-missing situations, IOSC covering four, six, and eight teeth, as well as full arch showed better accuracy in anterior gaps (p < 0.05). In posterior gaps, IOSC of two, four, six or eight teeth were more accurate (p < 0.05). The CNN predicted distinct optimal IOSC for different edentulous scenarios.

CONCLUSIONS

Implant impression accuracy can be significantly impacted by IOSC in different partially edentulous situations. The selection of IOSC should be customized to the specific dentition defect condition.

CLINICAL SIGNIFICANCE

The number of teeth scanned can significantly affect digital implant impression accuracy. For missing single or four anterior teeth, scan at least four or six neighboring teeth is acceptable. In lateral cases, two neighboring teeth may suffice, but extending over ten teeth, including contralateral side, might deteriorate the scan.

Accuracy of the Yakebot dental implant robotic system versus fully guided static computer-assisted implant surgery template in edentulous jaw implantation: A preliminary clinical study

AIMS

To compare the accuracy of the Yakebot dental implant robotic system with that of fully guided static computer-assisted implant surgery (CAIS) template in edentulous implantation.

MATERIALS AND METHODS

Thirteen patients with edentulous were recruited and divided into two groups: the Yake robotic system group (experimental) (n = 5) and the CAIS group (control) (n = 8). Postoperative cone-beam computed tomography (CBCT) was performed immediately, and the 3-dimensional positions of implants were obtained and compared with that in the preoperative design. The comparison showed platform, apical, depth, and angular deviations. A value of p < 0.05 was considered statistically significant.

RESULTS

A total of 84 implants (36 in the robotic group and 48 in the CAIS group) were placed. The mean deviation at the implant platform, apex, depth, and angle in the CAIS group was 1.37 ± 0.72 mm, 1.28 ± 0.68 mm, 0.88 ± 0.47 mm, and 3.47 ± 2.02°, respectively. However, the mean deviation at the implant platform, apex, depth, and angle in the robotic group was 0.65 ± 0.25 mm, 0.65 ± 0.22 mm, 0.49 ± 0.24 mm, and 1.43 ± 1.18°, respectively. Significant differences in the four types of deviation (p < 0.05) between the two groups were observed.

CONCLUSION

The accuracy of robotic system in edentulous implant placement was superior to that of the CAIS template, suggesting that robotic system is more accurate, safe, and flexible, can be considered a promising treatment in clinical practice.

Digital design of a hybrid bone and tooth-supported surgical guide in patients with unilateral few remaining natural teeth: a dental technique

A technique for the design of a hybrid tooth and bone-supported implant drilling guide is described. The patient was scanned using cone beam computed tomography and an optical intraoral scanner. The dicom file was segmented according to the area of interest composed of bone and the remaining natural teeth. The Standard Tessellation Language (STL) file was trimmed to only the teeth providing support, followed by merging between the bone and teeth files in one STL. The implant drilling guide was designed with the Real Guide software program, and the file was 3-dimensionally printed in clear surgical guide resin. This technique offers an accurate, cost-effective digitally designed implant placement guide for patients with long-span distal extension edentulous areas and few remaining natural dentitions providing distal bone support. It can also be used in patients with hemi maxillectomy for zygomatic implant placement. This type of surgical guide provides more accuracy in implant surgeries that require flab elevation by gaining more support from the remaining natural dentition.

The influence of guide stabilizers and their application sequences on trueness and precision of surgical guides in free end situations: An in vitro analysis

OBJECTIVES

To evaluate the impact of guide stabilizers and their application sequences on implant placement accuracy of guided implant surgery in multiple teeth loss at free end.

MATERIALS AND METHODS

In this study, 96 implants were placed in the regions of #34, #36, and #37 of 32 identical mandibular models. The influence of using guide stabilizers or not (group A and group B) and various guide stabilizers application sequences (group B: #34 → #36 → #37; group C: #36 → #34 → #37; group D: #37 → #34 → #36) on implant placement trueness and precision was investigated. Data were analyzed using T-tests and one-way ANOVA.

RESULTS

Group B showed significant benefits in enhancing implant placement precision. Compared to group A, it resulted in reducing 3D-deviation at crest and 2D deviation in vestibular-oral direction at both crest and apex. Furthermore, group D demonstrated greater improvement in global implant placement precision by reducing 2D deviation in mesial-distal direction at both crest and apex. Among the three different stabilizer application sequences, group D exhibited the highest level of implant placement precision.

CONCLUSIONS

In cases of missing teeth at distal free end, the use of guide stabilizers and their application sequences does not have a significant impact on implant placement trueness. However, they do improve implant placement precision compared to methods that do not utilize guide stabilizers. Specifically, applying a guide stabilizer first at the furthest implant site to change teeth loss classification from free end to edentulous space with posterior support is the most reliable sequence.

Evaluation of the accuracy of fully guided implant placement by undergraduate students and postgraduate dentists: a comparative prospective clinical study

PURPOSE

This study aimed to assess the accuracy of implant placement through three-dimensional planning and fully guided insertion, comparing outcomes between undergraduate and postgraduate surgeons.

METHODS

Thirty-eight patients requiring 42 implants in posterior single-tooth gaps were enrolled from the University Clinic for Prosthodontics at the Martin Luther University Halle Wittenberg and the Department of Prosthodontics, Geriatric Dentistry, and Craniomandibular Disorders of Charité University Medicine, Berlin. Twenty-two implants were placed by undergraduate students (n = 18), while 20 implants were placed by trainee postgraduate dentists (n = 5). Pre-operative intraoral scans and cone beam computed tomography images were performed for implant planning and surgical template fabrication. Postoperative intraoral scans were superimposed onto the original scans to analyze implant accuracy in terms of apical, coronal, and angular deviations, as well as vertical discrepancies.

RESULTS

In the student group, two implant insertions were performed by the assistant dentist because of intraoperative complications and, thus, were excluded from further analysis. For the remaining implants, no statistically significant differences were observed between the dentist and student groups in terms of apical (p = 0.245), coronal (p = 0.745), or angular (p = 0.185) implant deviations, as well as vertical discrepancies (p = 0.433).

CONCLUSIONS

This study confirms the viability of fully guided implant placement by undergraduate students, with comparable accuracy to postgraduate dentists. Integration into dental education can prepare students for implant procedures, expanding access and potentially reducing costs in clinical practice. Collaboration is essential for safe implementation, and future research should explore long-term outcomes and patient perspectives, contributing to the advancement of dental education and practice.

TRIAL REGISTRATION

DRKS, DRKS00023024, Registered 8 September 2020-Retrospectively registered, https://drks.de/search/de/trial/DRKS00023024 .

Case report and literature review: autonomous robotic system assisted palatal implantation at an anterior teeth site compromised by periapical cyst

Background

Immediate implant placement (IIP), which preserves gingival height and papilla shape while simultaneously accelerating the implant treatment period, has become a popular method due to its commendable clinical outcomes. Nonetheless, deploying immediate implants demands specific preconditions concerning the remaining alveolar bone. This poses a challenge to the accuracy of implant surgery.

Case presentation

In this report, we present the case of a 60-year-old woman with a left upper anterior tooth crown dislodged for over a month. Cone beam computed tomography (CBCT) revealed the absence of a labial bone wall on tooth 22, a remaining 1 mm bone wall on the labial side of the root apex, and a 17.2 mm*8.9 mm*4.7 mm shadow in the periapical region of the root apices of teeth 21 and 22, with the narrowest width on the sagittal plane being approximately 5 mm. After the surgeon removed the cyst, they completed the subsequent implantation surgery using an autonomous robot in a challenging aesthetic area. This method circumvented the potential exposure of the screw thread on the labial implant surface, assured initial implant stability.

Conclusion

Five months after the operation, the dental crown was restored. The implant remained stable, with yielding notable clinical results. To the best of our knowledge, this clinical case is the first to report the feasibility and precision of immediate implantation in anterior teeth site with periapical cyst removal, performed by an autonomous robotic surgical system. Autonomous robots exhibit exceptional accuracy by accurately controlling axial and angular errors. It can improve the accuracy of implant surgery, which may become a key technology for changing implant surgery. However, further clinical trials are still needed to provide a basis for the rapid development of robotic surgery field.

Clinical accuracy of partially guided implant placement in edentulous patients: A computed tomography-based retrospective study

OBJECTIVES

This retrospective study was intended to evaluate the clinical accuracy of partially guided template in guiding implant placement in edentulous patients.

METHODS

A total of 120 implants were placed in 24 patients with at least one completely edentulous arch with a partially guided system. Based on CBCT data, a repeatable method was used to measure linear and angular deviations of implants at 3D level in Mimics medical software. The influence of supporting tissue and implant region on the accuracy was assessed, followed by the evaluation of direction of linear deviations in biologically vital areas.

RESULTS

Linear deviations of all implants were 1.91 ± 0.68 mm, 1.47 ± 0.68 mm, and 1.02 ± 0.69 mm at apical, apical lateral, and apical vertical levels. When at the cervical, cervical lateral, and cervical vertical levels, the linear deviations were 1.53 ± 0.65 mm, 0.98 ± 0.53 mm, and 1.01 ± 0.69 mm, respectively. Angular deviation of all implants was 7.14 ± 3.41°. Implants guided by mucosa + tooth-supported templates showed higher linear deviations at apical vertical level (1.21 ± 0.72 mm vs. 0.86 ± 0.63 mm, p < .05) and cervical vertical level (1.18 ± 0.72 mm vs. 0.87 ± 0.63 mm, p < .05) than mucosa-supported templates, and implants in maxilla were found higher angular deviation than mandible (7.89 ± 3.61° vs. 6.29 ± 2.97°, p < .05).

CONCLUSIONS

The partially guided template served as clinically viable surgical assistance in implant placement in edentulous patients. When using mucosa + tooth-supported template or placing implants in maxilla, more caution was required, especially in biologically vital areas.

Stackable guide in implantology: A technical note

INTRODUCTION

With the rise of digital workflow, the production of implant guides is becoming increasingly easy and reproducible. The objective is to obtain an optimal correlation between the prosthetic and implant axis to ensuring the "X jaw - one day" concept in the short term and a sustainable technique in a long term TECHNIQUE: This approach requires a strict and rigorous preoperative evaluation. The data recording steps allow a complete visualization of the case and are used to custom the guide. The bone support is surmounted by several stages (positioning guide, drilling guide and the future temporary prosthesis).

CONCLUSION

Despite the time-consuming nature, this technique provides a reliable and reproducible protocol for immediate loading without compromising the prosthetic axis.

A systematic review of the accuracy of digital surgical guides for dental implantation

PURPOSE

This review aimed to reveal the influence of implant guides on surgical accuracy with regard to supporting types, manufacturing methods and design (including fixation screws and sleeves).

METHODS

A literature search related to accuracy of surgical guides for dental implantation was performed in Web of Science and PubMed. Studies with in vivo or in vitro deviation data published in recent 5 years (2018-2022) were included and assessed by Newcastle-Ottawa Scale with regard to risk of bias and reliability degree of clinical studies. Accuracy-related deviation data were summarized as forest plots and normal distributions.

RESULTS

Forty-one articles were included with high degree of credibility. Data showed that implant surgery accuracy can be achieved with mean distance deviation < 2 mm (most < 1 mm) and angular deviation < 8° (most < 5°).

CONCLUSIONS

Bilateral tooth-supported guides exhibited highest in vitro accuracy and similar in vivo accuracy to unilateral tooth-supported guides; mucosa-supported guides exhibit lowest in vivo accuracy, while its in vitro data showed low credibility due to mechanical complexity of living mucosa tissue. Milling exhibited higher in vivo accuracy of guides than 3d-printing, though further data support was needed. Design of fixation screws and sleeves of implant guides affected the surgical accuracy and might remain a research focus in near future. However, lack of universal evaluation standards for implantation accuracy remained a major problem in this field. The influence of implant guides on surgical accuracy revealed in this review might shed light on future development of dental implantology.

An additively manufactured, magnetically retained, and stackable implant surgical guide: A dental technique

The digital workflow for designing and fabricating a magnetically retained and stackable additively manufactured implant surgical guide is described. The technique should improve the stability of the stackable surgical guide and the accuracy of implant placement.

Guided Full Mouth Implant Rehabilitation in Atrophic Alveolar Ridges Using TTPHIL ALL TILT® Protocol: A Case Report With Three Years Follow-Up

Computer-assisted implant planning has become a key diagnostic and therapeutic tool in modern dentistry. This case report emphasizes the possibilities in modern implantology combining virtual implant planning, guided surgery with surgical templates, and immediate function. A 75-year-old female presented with maxillary and mandibular dentures and wanted fixed replacement in minimal appointments. Diagnosis, decision-making, and treatment approaches were based on clinical findings and detailed virtual three-dimensional implant planning. Guided implant placement of six implants in each arch using Tall and Tilted Pin Hole Immediate Loading Technique (TTPHIL ALL TILT®), and immediate loading with a provisional fixed dental prosthesis (FDP) was performed fulfilling patient's functional and esthetic demands in a minimally invasive manner. The final computer-assisted design/computer-assisted manufacturing (CAD/CAM) FDP with a titanium framework and ceramic layering was delivered after six months. At the three-year recall, the implant-supported FDP was free of any complications. Uneventful osseointegration of the dental implants and a healthy peri-implant mucosa were observed. Computer-assisted TTPHIL ALL TILT® technique including three-dimensional virtual implant planning, guided surgery, and CAD/CAM fabrication of provisional and final reconstructions allowed for a concise treatment workflow with favorable esthetic and functional outcomes in this maxillary and mandibular full-mouth case without the need of multiple surgeries in a short treatment time.

Application of titanium 3D-printed double-sleeve guide for zygomatic implants: A technique report

The unique anatomical structure of the atrophic edentulous maxilla limits the placement of endosteal root form dental implants without bone grafting and augmentation. Surgical placement of zygomatic implants in an optimal position remains challenging. This technique report illustrates a novel digital guide technology, including the design workflow, application method, and indications for assisting with the placement of zygomatic implants using a bone-supported titanium double-sleeve guide. In addition, when the implant body reaches the zygomatic bone following an intra-sinus path, including ZAGA type 0 and ZAGA type 1 cases, a matching window osteotomy surgical guide is used to locate the lateral window boundary and protect the sinus membrane. With this technique, the surgical procedure is simplified, and the precision of guided zygomatic implant placement is improved.

Accuracy and patient-centered results of static and dynamic computer-assisted implant surgery in edentulous jaws: a retrospective cohort study

OBJECTIVES

This study aimed to compare implant positioning accuracy and patient-centered results between static and dynamic computer-assisted implant surgery (s-CAIS and d-CAIS) in edentulous jaws.

MATERIAL AND METHODS

The current study retrospectively evaluated a total of 110 implants placed in 22 fully edentulous patients via s-CAIS or d-CAIS (n = 11). The accuracy of implant positioning was assessed by measuring the implant's angular deviation and deviation at the platform and apex from the preoperative design postoperatively. Patient-centered results, including preoperative and intraoperative patient-reported experiences and postoperative patient-reported outcomes, were extracted from the medical records. The nested t test and chi-square test were used to compare accuracy and patient-centered results between s-CAIS and d-CAIS postoperatively.

RESULTS

The implants in the s-CAIS group showed significantly smaller angular deviation (2.32 ± 1.23°) than those in the d-CAIS group (3.87 ± 2.75°). In contrast, the platform and apical deviation were significantly larger in s-CAIS (1.56 ± 1.19 mm and 1.70 ± 1.09 mm, respectively) than d-CAIS (1.02 ± 0.45 mm and 1.00 ± 0.51 mm, respectively). Furthermore, the implants in the s-CAIS group deviated significantly (p < 0.001) more toward the coronal direction than those in the d-CAIS group. Notably, all patients in the s-CAIS group reported an obvious foreign body sensation during surgery, representing a significant difference from the d-CAIS group.

CONCLUSIONS

Compared to s-CAIS, d-CAIS is a reliable technique for the placement of multiple implants in fully edentulous patients with less linear deviation and less foreign body sensation.

TRIAL REGISTRATION

The retrospective study was registered on the Chinese Clinical Trial Registry on August 8th, 2022, with registration number No. ChiCTR2200062484.

CLINICAL RELEVANCE

Despite the increasing use of computer- assisted implant surgery in fully edentulous patients, clinical evidence comparing implant positioning accuracy and patient-centered results between static and dynamic CAIS systems is scarce. Our study demonstrated that compared to s-CAIS, d-CAIS is a reliable technique for the placement of multiple implants in fully edentulous patients with less linear deviation.

Contribution of 3D printing for the surgical management of jaws cysts and benign tumors: A systematic review of the literature

BACKGROUND

Three-dimensional (3D) printing is now a widely recognized surgical tool in oral and maxillofacial surgery. However, little is known about its benefits for the surgical management of benign maxillary and mandibular tumors and cysts.

PURPOSE

The objective of this systematic review was to assess the contribution of 3D printing in the management of benign jaw lesions.

METHODS

A systematic review, registered in PROSPERO, was conducted using PubMed and Scopus databases, up to December 2022, by following PRISMA guidelines. Studies reporting 3D printing applications for the surgical management of benign jaw lesions were considered.

RESULTS

This review included thirteen studies involving 74 patients. The principal use of 3D printing was to produce anatomical models, intraoperative surgical guides, or both, allowing for the successful removal of maxillary and mandibular lesions. The greatest reported benefits of printed models were the visualization of the lesion and its anatomical relationships to anticipate intraoperative risks. Surgical guides were designed as drilling locating guides or osteotomy cutting guides and contributed to decreasing operating time and improving the accuracy of the surgery.

CONCLUSION

Using 3D printing technologies to manage benign jaw lesions results in less invasive procedures by facilitating precise osteotomies, reducing operating times, and complications. More studies with higher levels of evidence are needed to confirm our results.

Effect of the level of alveolar atrophy on implant placement accuracy in guided surgery for full-arch restorations supported by four implants: an in vitro study

BACKGROUND

A fixed screw-retained full-arch restoration supported by four implants is a popular treatment option for edentulous arches. Optimal alignment of implants is quite challenging in extremely atrophied edentulous cases, and a small amount of deviation is expected during guided surgery. This study aimed to compare implant accuracy among edentulous jaws with various levels of atrophy.

METHODS

Five separate copies of each Cawood and Howell model (III-V) were produced for the maxilla and mandible. A total of 120 implants (30 models). The implant accuracy was assessed based on angular deviations at the base (angle, 3D offset, distal, vestibular, and apical) and tip (3D offset, distal, vestibular, and apical).

RESULTS

The atrophy level of the jaws had a statistically significant effect on deviation; implants showed greater deviation from the planned location as the atrophy level increased.

CONCLUSION

Given that implant deviation increased with the degree of atrophy, a greater safety margin from important anatomical structures is recommended when planning implant location for guided surgery in Cawood and Howell V cases.

A Custom-Made Surgical Guide for Accurate Enucleation of Nasopalatine Duct Cysts: A Technical Note and Case Report

Nasopalatine cysts are common nonodontogenic cysts that occur in the maxilla. During the nucleation of large cysts extending to the floor of the nasal cavity, care must be taken to avoid damage to the nasal mucosa. In the present report, an innovative custom-made surgical guide made by a Three-dimensional printer is introduced for accurate enucleation surgery. The patient's cone-beam computerized tomography and dental model scan data were obtained, and a tooth-supported type of surgical guide was designed containing a circular plate structure showing the size of the cystic region, an indicator that showed the position of the bottom of the cyst, and a sliding stopper that was used to accurately indicate the position of the deepest cyst wall. The surgical tool enabled us to indicate the accurate size, location of the cysts, and approach direction. Although effective and accurate navigation systems have become increasingly available, the cost-effective and accurate computer-aided design/computer-aided manufacturing surgical guide system introduced in the present report could support the safe enucleation of large nasopalatine duct cysts.

Long-Term Effect of Guided Implant Surgery on Clinical Outcomes and Peri-Implantitis of Maxillary Implants-An Observational Cohort Study

(1) Although the accuracy of static computer-aided implant surgery (sCAIP) is well reported, information on its long-term effect on peri-implant health and complications is scarce. (2) Twenty-six patients initially treated were recalled. Implant survival, radiographic bone level, peri-implant health, and complications were registered. A multilevel regression model was applied to study the relationship between the research variables. (3) Sixteen patients participated in this study (average age 58.5 years; range 27.8-73.8). The mean follow-up time was 9.1 years (range 7.3-11.3). Two implants failed, resulting in a survival rate of 97.1%. The mean bone level change corresponded to a loss of 0.63 mm (SD 1.90) for the whole group, 0.17 mm (SD 1.46), and 0.91 mm (SD 2.09) for tooth- and mucosa-supported guides, respectively. The mean PPD for the total group was 4.24 mm (SD 1.25), and 3.79 mm (SD 0.97) and 4.51 mm (SD 1.33) for the tooth- and mucosa-supported guides, respectively. Four implants (6.3%) were diagnosed with peri-implantitis. Coronal deviation was slightly associated with having a negative impact on bone level at follow-up, but this was not statistically significant. Seven patients (43.8%) experienced technical complications. Biological complications were seen in 3/16 patients (18.75%). (4) SCAIP may contribute to more predictable implant placement; the long-term clinical outcome is similar to conventional nonguided surgery.

The efficacy and accuracy of 3D-guided orthodontic piezocision: a randomized controlled trial

BACKGROUND

No randomized controlled trial (RCT) has studied the accuracy of surgical guides used in terms of orthodontic treatment acceleration. Therefore the aim of this trial was to assess computer-guided piezocision-based orthodontic.

MATERIALS AND METHODS

Thirty-two patients with severely crowded upper anterior teeth were enrolled and randomly allocated to either the experimental group (ExpG) or the control one. Subjects of the ExpG received three-dimensional (3D) guided piezoelectric corticotomies on the buccal alveolar bone of the anterior region. Five piezocision cuts were properly performed between each anterior teeth and the adjacent in virtual models. Surgical guides were designed and 3D-printed with preplanned slots that guide gingival and then piezoelectric incisions. The patients underwent Cone-Beam Computed Tomography CBCT before and immediately after surgery. Thus, Predesigned piezocisions were compared to the actual ones in attempt to measure three dimensional deviations of the applied peizocisions.

RESULTS

Ninety-six severe maxillary dental crowding were assigned for eligibility, 40 of them met the inclusion criteria. Thirty-two participants were randomly allocated to the trial`s groups. No patient was lost to follow-up neither from the control nor the experimental group. Overall alignment time (OAT) was reduced by 53% in the experimental group compared to the control group. The mean of the 3D deviation of the surgical guide was 0.23 mm (standard deviation 0.19 mm).

CONCLUSION

The values of the surgical guide deviation was nearly null, which confirms that this innovative technique is clinically applicable. Furthermore, this technique was impressively effective in accelerating orthodontic tooth movement.

TRIAL REGISTRATION

This trial was registered at The ISRCTN registry (ID: ISRCTN65498676 Registration date: 07/04/2021).

Accuracy of dental implant placement using static versus dynamic computer-assisted implant surgery: An in vitro study: Accuracy of static vs. dynamic CAIS

OBJECTIVES

This in-vitro study compared the accuracy of implant placement using static versus dynamic computer-assisted implant surgery (CAIS) at two implant sites.

METHODS

Partially edentulous maxillary models were 3D-printed, and two implants (Straumann TL RN4.1 × 10mm) were inserted in FDI positions 15 and 16 per model using two CAIS approaches (10 models per approach). A three-dimensional (3D) reconstruction tool was used for implant planning, surgical guide design, and measuring implant positioning accuracy. In static CAIS, the implants were placed with 3D-printed surgical guides (n=20); in dynamic CAIS, real-time navigation was performed (n=20). Primary outcomes were defined as coronal and apical global deviation as well as angular deviations and deviation comparison between implants placed at positions 15 and 16; the secondary outcome was the bi-directional deviation in mesial-distal, buccal-palatal, and apical-coronal direction.

RESULTS

The mean±SD 3D-deviation at implant platform and apex levels for static CAIS in position 15 was 0.81±0.31mm, 1.41±0.37mm, and in position 16 was 0.67±0.31mm, 1.07±0.32mm.

PRIMARY OUTCOMES

buccal-palatal deviation is higher using static CAIS, and mesial-distal deviation is higher in dynamic CAIS. In position 15, mesial-distal deviation at the apex and the platform were lower in static approaches than in dynamic ones. In implant position 16, buccal-palatal deviation at the apex was lower in the dynamic group than with static ones.

SECONDARY OUTCOMES

for bi-directional analysis, buccal-palatal deviation at the platform (P=0.0028) and mesial-distal deviation at the apex (P=0.0056) were significantly lower in molar sites using static CAIS. Mesial-distal deviation at the apex (P=0.0246) revealed significantly lower values in position 16 following dynamic CAIS.

CONCLUSIONS

Both static and dynamic CAIS resulted in accurate implant placement. However, dynamic CAIS exhibited higher deviation in the mesial direction in an in-vitro setting. In addition, the implant site affects the accuracy of both CAIS approaches.

CLINICAL SIGNIFICANCE

Static CAIS demonstrates the highest accuracy for guided implant placement today.

An in-vitro analysis of the accuracy of different guided surgery systems - They are not all the same

OBJECTIVES

Different static computer-assisted implant surgery (sCAIS) systems are available that are based on different design concepts. The objective was to assess seven different systems in a controlled environment.

MATERIALS AND METHODS

Each n = 20 implants were placed in identical mandible replicas (total n = 140). The systems utilized either drill-handles (group S and B), drill-body guidance (group Z and C), had the key attached to the drill (group D and V), or combined different design concepts (group N). The achieved final implant position was digitized utilizing cone-beam tomography and compared with the planned position. The angular deviation was defined as the primary outcome parameter. The means, standard deviation, and 95%-confidence intervals were analyzed statistically with 1-way ANOVA. A linear regression model was applied with the angle deviation as predictor and the sleeve height as response.

RESULTS

The overall angular deviation was 1.94 ± 1.51°, the 3D-deviation at the crest 0.54 ± 0.28 mm, and at the implant tip 0.67 ± 0.40 mm, respectively. Significant differences were found between the tested sCAIS systems. The angular deviation ranged between 0.88 ± 0.41° (S) and 3.97 ± 2.01° (C) (p < .01). Sleeve heights ≤4 mm are correlated with higher angle deviations, sleeve heights ≥5 mm with lower deviations from the planned implant position.

CONCLUSIONS

Significant differences were found among the seven tested sCAIS systems. Systems that use drill-handles achieved the highest accuracy, followed by the systems that attach the key to the drill. The sleeve height appears to impact the accuracy.

Virtual 3-dimensional representation of a completely edentulous patient for computer-aided static implant planning

A technique is described to create a virtual 3-dimensional representation of an edentulous patient by aligning the facial, intraoral, and cone beam computed tomography scans guided by an additively manufactured scan body. Having the virtual patient facilitated the prosthetically driven implant planning, the additive manufacturing of the surgical implant guides, and the interim dental restorations.

Minimal invasiveness at dental implant placement: A systematic review with meta-analyses on flapless fully guided surgery

Flapless and fully guided implant placement has the potential to maximize efficacy outcomes and at the same time to minimize surgical invasiveness. The aim of the current systematic review was to answer the following PICO question: "In adult human subjects undergoing dental implant placement (P), is minimally invasive flapless computer-aided fully guided (either dynamic or static computer-aided implant placement (sCAIP)) (I) superior to flapped conventional (free-handed implant placement (FHIP) or cast-based/drill partially guided implant placement (dPGIP)) surgery (C), in terms of efficacy, patient morbidity, long-term prognosis, and costs (O)?" Randomized clinical trials (RCTs) fulfilling specific inclusion criteria established to answer the PICO question were included. Two review authors independently searched for eligible studies, screened the titles and abstracts, performed full-text analysis, extracted the data from the published reports, and performed the risk of bias assessment. In cases of disagreement, a third review author took the final decision during ad hoc consensus meetings. The study results were summarized using random effects meta-analyses, which were based (wherever possible) on individual patient data (IPD). A total of 10 manuscripts reporting on five RCTs, involving a total of 124 participants and 449 implants, and comparing flapless sCAIP with flapped FHIP/cast-based partially guided implant placement (cPGIP), were included. There was no RCT analyzing flapless dynamic computer-aided implant placement (dCAIP) or flapped dPGIP. Intergroup meta-analyses indicated less depth deviation (difference in means (MD) = -0.28 mm; 95% confidence interval (CI): -0.59 to 0.03; moderate certainty), angular deviation (MD = -3.88 degrees; 95% CI: -7.00 to -0.77; high certainty), coronal (MD = -0.6 mm; 95% CI: -1.21 to 0.01; low certainty) and apical (MD = -0.75 mm; 95% CI: -1.43 to -0.07; moderate certainty) three-dimensional bodily deviations, postoperative pain (MD = -17.09 mm on the visual analogue scale (VAS); 95% CI: -33.38 to -0.80; low certainty), postoperative swelling (MD = -6.59 mm on the VAS; 95% CI: -19.03 to 5.85; very low certainty), intraoperative discomfort (MD = -9.36 mm on the VAS; 95% CI: -17.10 to -1.61) and surgery duration (MD = -24.28 minutes; 95% CI: -28.62 to -19.95) in flapless sCAIP than in flapped FHIP/cPGIP. Despite being more accurate than flapped FHIP/cPGIP, flapless sCAIP still resulted in deviations with respect to the planned position (intragroup meta-analytic means: 0.76 mm in depth, 2.57 degrees in angular, 1.43 mm in coronal, and 1.68 in apical three-dimensional bodily position). Moreover, flapless sCAIP presented a 12% group-specific intraoperative complication rate, resulting in an inability to place the implant with this protocol in 7% of cases. Evidence regarding more clinically relevant outcomes of efficacy (implant survival and success, prosthetically and biologically correct positioning), long-term prognosis, and costs, is currently scarce. When the objective is to guarantee minimal invasiveness at implant placement, clinicians could consider the use of flapless sCAIP. A proper case selection and consideration of a safety margin are, however, suggested.

Prevention of peri-implant disease in edentulous patients with fixed implant rehabilitations

OBJECTIVES

To provide an overview about the current approaches to prevent peri-implant diseases in edentulous patients with complete-arch implant-supported prostheses, and to review the clinical applications of the latest digital technologies for implant prosthodontics.

METHODS

A review of the guidelines to prevent peri-implant diseases in patient's receiving complete-arch implant-supported prostheses including facially driven treatment planning procedures using either conventional or digital methods, computer-aided implant planning procedures, and prosthodontic design variables including the optimal number and distribution of dental implants, implant to abutment connection type, implant or abutment level design, screw- or cement-retained alternatives, prostheses contours, and material selection is provided. Furthermore, an outline of the current therapeutic management approaches to address peri-implant diseases is reviewed.

CONCLUSIONS

Clinicians should understand and know different planning and design-related variables that can affect biological and mechanical complication rates of complete-arch implant-supported prostheses. Maintenance protocols are fundamental for minimizing biological and mechanical complications.

Investigation on the application of digital guide templates guided dental implantation in China

BACKGROUND

The aim of this survey is to investigate the application of digital guide templates (DGTs) across China, and the views and attitudes of oral health professionals toward them.

METHODS

This survey was prepared, distributed, and collected by WJX. Chinese oral health professionals were invited to participate in it. The basic information of respondents, the application of DGTs, and the views and attitudes toward their status quo and development were statistically described. Chi-square test was used to evaluate the correlation between the basic information of respondents and the application of DGTs as well as the views and attitudes toward them.

RESULTS

A total of 276 questionnaires were collected, of which 273 were identified as valid. 269 (98.5%) respondents were dental clinical workers, 204 (74.7%) were dental clinical implant workers, and 152 (55.7%) had been engaged in the implant industry for more than five years. The chi-square test showed that working years were significantly correlated with the half-guided, tooth-supported, and mucosa-supported DGTs (P < 0.05); and professional backgrounds and working years presented significant differences in the views and attitudes toward the status quo and development of DGTs (P < 0.05). The questionnaires also made a preliminary investigation and evaluation on the factors influencing accuracy, indications, doctors' recommendations and relevant training.

CONCLUSION

Most respondents held a positive attitude toward the accuracy and development of DGTs. This survey can point out the direction for the improvement of DGTs, and provide a reference for the study of factors affecting implant accuracy, the establishment of a training system, and the understanding of clinicians' current views on DGTs. Trial registration This survey was approved by the Ethics Review Committee of Chenghuaxinguanghua Dental Clinic (Approval NO. CDCIRB-D-2021-201).

Accuracy of Augmented Reality-Assisted Navigation in Dental Implant Surgery: Systematic Review and Meta-analysis

BACKGROUND

The novel concept of immersive 3D augmented reality (AR) surgical navigation has recently been introduced in the medical field. This method allows surgeons to directly focus on the surgical objective without having to look at a separate monitor. In the dental field, the recently developed AR-assisted dental implant navigation system (AR navigation), which uses innovative image technology to directly visualize and track a presurgical plan over an actual surgical site, has attracted great interest.

OBJECTIVE

This study is the first systematic review and meta-analysis study that aimed to assess the accuracy of dental implants placed by AR navigation and compare it with that of the widely used implant placement methods, including the freehand method (FH), template-based static guidance (TG), and conventional navigation (CN).

METHODS

Individual search strategies were used in PubMed (MEDLINE), Scopus, ScienceDirect, Cochrane Library, and Google Scholar to search for articles published until March 21, 2022. This study was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and registered in the International Prospective Register of Systematic Reviews (PROSPERO) database. Peer-reviewed journal articles evaluating the positional deviations of dental implants placed using AR-assisted implant navigation systems were included. Cohen d statistical power analysis was used to investigate the effect size estimate and CIs of standardized mean differences (SMDs) between data sets.

RESULTS

Among the 425 articles retrieved, 15 articles were considered eligible for narrative review, 8 articles were considered for single-arm meta-analysis, and 4 were included in a 2-arm meta-analysis. The mean lateral, global, depth, and angular deviations of the dental implant placed using AR navigation were 0.90 (95% CI 0.78-1.02) mm, 1.18 (95% CI 0.95-1.41) mm, 0.78 (95% CI 0.48-1.08) mm, and 3.96° (95% CI 3.45°-4.48°), respectively. The accuracy of AR navigation was significantly higher than that of the FH method (SMD=-1.01; 95% CI -1.47 to -0.55; P<.001) and CN method (SMD=-0.46; 95% CI -0.64 to -0.29; P<.001). However, the accuracies of the AR navigation and TG methods were similar (SMD=0.06; 95% CI -0.62 to 0.74; P=.73).

CONCLUSIONS

The positional deviations of AR-navigated implant placements were within the safety zone, suggesting clinically acceptable accuracy of the AR navigation method. Moreover, the accuracy of AR implant navigation was comparable with that of the highly recommended dental implant-guided surgery method, TG, and superior to that of the conventional FH and CN methods. This review highlights the possibility of using AR navigation as an effective and accurate immersive surgical guide for dental implant placement.

Retentive design of a small surgical guide for implant surgery: An in-vitro study

OBJECTIVES

Instability of the surgical guide is an overlooked factor that can result in a difference between the planned and the actual positions of an implant. Our aim was to compare the stability of the retentive surgical guide (RSG) with a conventional surgical guide (CSG) in an in-vitro experiment.

METHODS

A platform to evaluate the stability of the surgical guide was designed using 3D-modelling software (Meshmixer 3.5, Autodesk). Imaging data from 15 patients with a single missing tooth were used to plan the virtual implant. Two surgical guides were designed (Blue Sky Plan 4.8, Blue Sky Bio) and 3D printed (Form2, Dental SG resin, Formlabs) for each case: the CSG with the default, predetermined software settings, and the RSG, designed on a dental model with a 0.1-mm undercut and altered production parameters (reduced guide-to-teeth offset of 0.07 mm, reduced guide thickness of 2.3 mm and a retentive clasp in a marginal area). The dental models were reproducibly secured on the testing platform using a digital force gauge, and the surgical guides were positioned. An increasing force of 0.1 N, 1 N, 2.5 N, and 5 N was sequentially applied from the buccal and the oral directions to the surgical guide via a drill handle. For each force, either the magnitude of the guide's displacement was captured with an intra-oral scanner (CEREC Omnicam AC, Dentsply Sirona; software version: SW 4.5.2) or the dislodgement of the guide was recorded. Scans were imported for analysis (GOM Inspect 2018, GOM GmbH), and library files of the surgical guides and implants were superimposed as a joined complex. The deviation of the implant's position was calculated from the displacement of the guide's position RESULTS: Three-way repeated measures using ANOVA revealed a more significant guide displacement and virtually projected implant deviation in the CSG group than the RSG group and with increasing force in all the deviation parameters. Both groups showed greater resistance to the displacement with the force applied from the oral direction than the buccal direction. The application of the force in the buccal direction resulted in guide dislodgements of 13% and 0% for the CSG and RSG, respectively. In the oral direction, the dislodgement rates were 33% and 7% for the CSG and RSG, respectively.

CONCLUSIONS

Within the limitations of this study, the retentive design increased the stability of the surgical guide and, consequently, the accuracy of the virtually projected implants in comparison to the conventional surgical guide designed using the default settings. Clinical trials are needed to confirm its advantages in clinical use.

CLINICAL SIGNIFICANCE

With a simple modification to the design, the surgical guide retention provided greater stability, with smaller deviations under loading; this resulted in improved implant precision parameters without requiring additional materials or software. Further studies are needed to assess the clinical feasibility of this surgical guide with improved retention and function.

Process parameter optimization for removable partial denture frameworks manufactured by selective laser melting

STATEMENT OF PROBLEM

Selective laser melting (SLM), an additive manufacturing technology, is expected to replace the traditional lost-wax casting process used in producing removable partial denture (RPD) frameworks. However, studies comparing the accuracy of RPD frameworks and the effects of process parameters are lacking.

PURPOSE

The purpose of this in vitro study was to optimize SLM process parameters and use a quantitative analysis method to improve the accuracy of 3D-printed RPD frameworks.

MATERIAL AND METHODS

The orientation and support structure of Kennedy Class II RPDs were designed in various ways by using 2 different software programs, CAMbridge and Magics. The optimum melt-pool parameters, including laser power, scan speed, hatch distance, and layer thickness, were determined empirically before manufacturing 12 RPD frameworks with 4 different process designs by using SLM (n=3). The accuracy of the RPD frameworks was determined by 3D scanning and comparing the 3D scan data with the original standard tessellation language (STL) RPD design with the best-fit algorithm of the Geomagic software program.

RESULTS

Optimum melt-pool parameters were found with the function of density, surface roughness, and productivity (P=180 W, v=1200 mm/s, h=60 μm, t=30 μm). RPD frameworks fabricated by the optimized process parameters (167 ±105 μm) showed significantly better (P<.05) mean ±standard deviation accuracy than the 3 other groups of RPD frameworks manufactured by using the nonoptimized process parameters (180 ±121 μm to 222 ±136 μm). The best accuracy was found with the transverse orientation and interconnected support structure.

CONCLUSIONS

With the optimized design of process parameters, clinically acceptable RPD frameworks were produced. The accuracy of RPD frameworks fabricated by using SLM varied according to the design of the process parameters, indicating that SLM technology can replace the traditional lost-wax casting process.

Comparison between flapless-guided and conventional surgery for implant placement: a 12-month randomized clinical trial

OBJECTIVES

The study was aimed at comparing implants installed with guided and conventional surgery.

MATERIAL AND METHODS

Twenty-nine total edentulous patients were selected, and maxillary contralateral quadrants were randomly assigned to static computer-aided implant surgery (S-CAIS): flapless computer-guided surgery, and conventional surgery (CS): flap surgery with conventional planning. Tomography scans were performed at baseline and 10 days after the surgery for deviation measurement, and radiography was done at baseline and after 6 and 12 months, for peri-implant bone level (PIBL) analysis. Peri-implant fluid and subgingival biofilm were collected to evaluate bone markers and periodontal pathogens.

RESULTS

S-CAIS showed less linear deviation at the apical point and the midpoint and less angular deviation (p < 0.05), with greater depth discrepancy in the positioning of the platform (p < 0.05). Higher values of vertical PIBL were observed for the S-CAIS group at baseline (p < 0.05), while lower values of horizontal PIBL were observed for CS (p < 0.05). Bone markers and Tf presented higher levels in CS (p < 0.05). Flapless S-CAIS allowed smaller linear and angular deviations than the conventional technique.

CONCLUSION

However, PIBL was higher in S-CAIS; the conventional technique led to a greater angiogenic and bone remodeling activity by elevating the angiogenic levels and bone markers.

CLINICAL RELEVANCE

Evaluating the different implant insertion techniques can guide clinical and surgical regarding the accuracy, the release pattern of bone markers, and the peri-implant bone level.

TRIAL REGISTRATION

ReBEC-RBR-8556fzp.

Flexible surgical guide to improve implant placement accuracy. Dental technique

Surgical guide retention and stability is a key factor for accurate implant placement in static computer assisted implant placement protocol. The use of flexible acrylic resin to construct the surgical guide allows engaging undercuts and extending the guide to the vestibules and hence maximizing the retention and stability of the guide which in turn enhances the accuracy of the placed implant.

Computer-Guided Surgery for Dental Implant Placement: A Systematic Review

Implant therapy is currently the treatment of choice for the replacement of missing teeth. Correct implant positioning is of vital importance. To this end, radiographic techniques providing 3D information and guided surgery techniques, both static and dynamic, have been developed. The primary objective of this work is to study whether placing dental implants in partially edentulous patients with guided surgery techniques results in less, equal or greater precision than placing them freehand. The secondary objectives are to gain an understanding of the advantages and disadvantages, indications, limitations, and complications of this type of surgery. A literature search was performed in Pubmed and BVS, and six randomized clinical trials meeting the marked inclusion criteria were included. The different guided surgery techniques were compared with each other and with the traditional method. Freehand surgery was found to be the least accurate, as the implants placed with this technique showed the largest deviations between the planned position and the final position, both when calculating the global (3D) deviation and when measuring the deviation in each of the axes (vertical, mesio-distal, bucco-lingual and lateral), and the angular deviation and voxel overlap. In contrast, the most accurate surgeries were fully guided and half-guided, with the smallest deviations between the planned and final implant position. With any guided surgery technique, more precise implant positioning is achieved than with freehand placement. Advantages include reduced trauma and surgery time; disadvantages include reduced primary implant stability and higher cost. This type of surgery is more indicated in cases of critical anatomy, but may encounter limitations in terms of cost, degree of buccal opening, visibility and adjustment of the guides and the need for prior familiarization with the procedure. Nevertheless, this surgical technique reduces the complication rate.

Surgical guides for dental implants: measurement of the accuracy using a freeware metrology software program

PURPOSE

Manufacturing-related inaccuracies of surgical guides for static computer-aided implant surgery may contribute to the overall potential error in the obtained implant position. Measuring such inaccuracies before surgery may provide quality control assessment and improve the safety and outcomes of guided implant surgery. This technical report demonstrates a workflow to measure the accuracy of a surgical guide (at the intaglio surface and sleeve housing) using a freeware metrology software program.

METHODS

The scan of a milled surgical guide was aligned to and compared with its reference computer-aided design model using a freeware metrology software program (GOM Inspect suite; GOM GmbH). The trueness of the internal surface of the surgical guide was measured as an indicator of adaptation to the supporting tissues. Additionally, some features were constructed to extract the plane at the sleeve entrance and sleeve axis and to set a local coordinate system on them. Linear and angular deviations between the planned and obtained sleeve axes were measured using this system. Such measurements, together with additional known data (sleeve offset and the planned implant length), allowed the estimation of linear errors in implant position at both the implant platform and apex by applying common geometric formulas, based on the assumption that all other sources of error in implant position could be effectively controlled during the surgical procedure.

CONCLUSION

The proposed digital technique is a cost-effective approach for quality control of the inaccuracies of a surgical guide and predicts the related potential error in implant position.