In Vitro Comparison between Metal Sleeve-Free and Metal Sleeve-Incorporated 3D-Printed Computer-Assisted Implant Surgical Guides

Accuracy of open-sleeved vs. closed-sleeved static computer-assisted implant systems in immediate maxillary molar implant placement: An in vitro study

OBJECTIVES

The objective of this study is (1) to compare the accuracy of an open-sleeved static computer-assisted implant system (sCAIS) with a closed-sleeve sCAIS and free-hand approach in immediate implant placement (IIP) of maxillary molar sites and (2) to investigate the influence of socket morphology on these approaches.

MATERIALS AND METHODS

Ninety partially edentulous duplicated maxillary models simulating three different molar sockets (type A, B, and C based on Smith and Tarnow's classification) were investigated. Three modalities, including sCAIS with open-sleeves, sCAIS with closed-sleeves, and free-hand approach, were applied separately to 30 models with 120 sockets. A customized Python script automatically measured the deviations between the virtual and actual implant positions for all 360 implants.

RESULTS

The 3D deviations of sCAIS were significantly influenced by the socket and sleeve types. Both guided groups exhibited significantly less deviation than the free-hand approach. Type A and C sockets resulted in better implant positions than type B socket sites. In type B sockets, the open-sleeve group achieved significantly less deviation compared to the closed-sleeve group, with respect to apical global (1.34 ± 0.53 vs. 1.84 ± 0.59 mm), coronal horizontal (0.68 ± 0.36 vs. 0.93 ± 0.34 mm), apical horizontal (1.21 ± 0.59 vs. 1.74 ± 0.63 mm), and angular (3.30 ± 1.41 vs. 4.41 ± 1.96°) deviations.

CONCLUSIONS

Guided implant surgery significantly reduces deviations during molar IIP compared to free-hand procedures. Furthermore, the use of open-sleeve sCAIS appears to be more effective in minimizing deviations in type B sockets when compared with the closed-sleeve guided system.

A literature review on prosthetically designed guided implant placement and the factors influencing dental implant success

This is an extensive review of the literature on prosthetically designed implant planning with particular regard to the factors influencing dental implant success. Electronic searches on PubMed and the Cochrane Central Register of Controlled Trials and manual searches were performed. The author selected the studies according to the inclusion and exclusion criteria. Meta-analysis of implant placement accuracy and a qualitative review of potential influencing factors were performed.This literature review will explore prosthetically designed implant placement and its influence on dental implant success. By examining the factors that impact implant outcomes, this review aims to provide clinicians with a comprehensive understanding of the key considerations and best practices in achieving successful implant placements. Ultimately, this knowledge can contribute to enhancing patient care and the long-term success of dental implant treatments.

Cooling Efficiency of Sleeveless 3D-Printed Surgical Guides with Different Cylinder Designs

Background and Objectives: Surgical guides might impede the flow of coolant to the implant drills during the preparation of the implant bed, potentially contributing to increased temperatures during bone drilling. The objective of this experimental study was to assess the cooling efficiency of various guiding cylinder designs for sleeveless surgical guides used in guided surgery. Materials and Methods: In this experimental study, surgical guides with three different guiding cylinder designs were printed. One group had solid cylinders (control) and two test groups (cylinders with pores and cylinders with windows). Forty customized polyurethane blocks with type III bone characteristics were fitted into the guide and fixed in a vise, and implant bed preparations were completed using a simplified drilling protocol with and without irrigation. An infrared thermographic camera was used to record the temperature changes during drilling at the coronal, middle, and apical areas. ANOVA test and Games-Howell post hoc test were used to determine significant thermal differences among groups. Results: A significant thermal increase was observed at the coronal area in the group without irrigation (39.69 ± 8.82) (p < 0.05). The lowest thermal increase was recorded at the surgical guides with windows (21.451 ± 0.703 °C) compared to solid (25.005 ± 0.586 °C) and porous surgical guides (25.630 ± 1.004) (p < 0.05). In the middle and apical areas, there were no differences between solid and porous cylinders (p > 0.05). Conclusions: 3D-printed sleeveless surgical guides with window openings at the guiding cylinders reduce the temperature elevation at the cortical bone in guided implant surgery.

Effect of pilot-guided implant placement concept on the accuracy of osteotomy preparation and implant placement

PURPOSE

To evaluate the accuracy of osteotomy preparation and implant placement for 3 pilot-guided (PG) concepts, namely, a surgical template with a metal sleeve (MS), a surgical template with an in-built nonmetal sleeve (NMS), and a surgical template with an in-built nonmetal sleeve for round bur indentation (RB).

METHODS

Surgical models with missing maxillary molars were studied. The MS templates were designed to accept metal sleeves, while the NMS and RB templates were designed with in-built nonmetal sleeves. Ten templates were tested per group (n = 10). After each step (pilot drilling, 2nd drilling, 3rd drilling, profiling, and implant placement), the surgical model was scanned and compared against the planning model to determine maximum horizontal deviation (MHD) and maximum angle deviation (MAD).

RESULTS

The MS and NMS templates exhibited a similar increase in MHD with successive drilling steps. The MAD for the pilot drilling step was significantly lower for MS than for the other groups. However, the differences among groups for MHD and MAD diminished in later steps. All templates had an MHD of 1.0 mm or less and an MAD less than 8°.

CONCLUSION

The investigated PG implant placement concepts resulted in similar deviations in the placed implants.

Advancing accuracy in guided implant placement: A comprehensive meta-analysis: Meta-Analysis evaluation of the accuracy of available implant placement Methods

OBJECTIVES

This meta-analysis aimed to determine the accuracy of currently available computer-assisted implant surgery (CAIS) modalities under in vitro conditions and investigate whether these novel techniques can achieve clinically acceptable accuracy.

DATA

In vitro studies comparing the postoperative implant position with the preoperative plan were included. Risk of bias was assessed using the Quality Assessment Tool For In Vitro Studies (QUIN Tool) and a sensitivity analysis was conducted using funnel plots.

SOURCES

A systematic search was performed on April 18, 2023, using the following three databases: MEDLINE (via PubMed), EMBASE, and Cochrane Central Register of Controlled Trials. No filters or restrictions were applied during the search.

RESULTS

A total of 5,894 studies were included following study selection. Robotic- and static CAIS (sCAIS) had the most accurate and clinically acceptable outcomes. sCAIS was further divided according to the guidance level. Among the sCAIS groups, fully guided implant placement had the greatest accuracy. Augmented reality-based CAIS (AR-based CAIS) had clinically acceptable results for all the outcomes except for apical global deviation. Dynamic CAIS (dCAIS) demonstrated clinically safe results, except for horizontal apical deviation. Freehand implant placement was associated with the greatest number of errors.

CONCLUSIONS

Fully guided sCAIS demonstrated the most predictable outcomes, whereas freehand sCAIS demonstrated the lowest accuracy. AR-based and robotic CAIS may be promising alternatives.

CLINICAL SIGNIFICANCE

To our knowledge, this is the first meta-analysis to evaluate the accuracy of robotic CAIS and investigate the accuracy of various CAIS modalities.

Integrating a mouth opening assessment of virtual patients to prevent intraoperative challenges during treatment

Template-guided implant surgery in the posterior region or zygomatic implant surgery using dynamic navigation systems is often hindered if a patient has limited mouth opening. To overcome the problem, the authors have proposed a novel digital protocol that integrates the use of a facial scan for the assessment of the maximal mouth opening of a virtual patient to assist in preoperative planning, thereby minimizing the likelihood of intraoperative obstruction of the surgical site. The proposed method is cost effective and can be easily used in clinical practice.

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.

The 3D Printing and Evaluation of Surgical Guides with an Incorporated Irrigation Channel for Dental Implant Placement

Dental implant insertion requires the preparation of the implant bed via surgical drilling. During this stage, irrigation is essential to avoid thermal damage to the surrounding bone. Surgical guides enhance the accuracy of the implant site preparation, but they mask the drilling site, hampering coolant delivery. A variety of designs are aimed at improving the coolant access to the target site. Using standard dental implant simulation software, this paper presents an in-house design and 3D printing workflow for building surgical guides that incorporate a coolant channel directed toward the entry point of the burr. The proposed design was evaluated in terms of the bone temperature elevations caused by drilling performed at 1500 rpm, under an axial load of 2 kg, and irrigation with 40 mL/min of saline solution at 25 °C. Temperature measurements were performed on porcine femoral pieces, in the middle of the cortical bone layer, at 1 mm from the edge of the osteotomy. The mean temperature rise was 3.2 °C for a cylindrical sleeve guide, 2.7 °C for a C-shaped open-sleeve guide, and 2.1 °C for the guide with an incorporated coolant channel. According to a one-way ANOVA, the differences between these means were marginally insignificant (p = 0.056). The individual values of the peak temperature change remained below the bone damage threshold (10 °C) in all cases. Remarkably, the distribution of the recorded temperatures was the narrowest for the guide with internal irrigation, suggesting that, besides the most effective cooling, it provides the most precise control of the intraosseous temperature. Further studies could test different design variants, experimental models (including live animals), and might involve computer simulations of the bone temperature field.

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.

Accuracy of a custom two-piece surgical guide for all-on-four dental implant placement: An in vitro study

STATEMENT OF PROBLEM

Although fully guided dental implant surgery has been reported to provide a high degree of accuracy, it has disadvantages including the lack of external irrigation during osteotomy formation and the need for special drills and equipment. Whether a custom 2-piece surgical guide has sufficient accuracy is unclear.

PURPOSE

The purpose of this in vitro study was to design and fabricate a new surgical guide concept that fully guides the placement of implants to the desired position and angulation without affecting the external irrigation during osteotomy preparation, to eliminate the need for a special armamentarium, and to determine the accuracy of the guide.

MATERIAL AND METHODS

A 2-piece surgical guide was 3-dimensionally designed and fabricated. Implants were placed according to the all-on-4 concepts in laboratory casts using the newly fabricated surgical guide. Placement accuracy was determined from a postoperative cone beam computed tomography scan that was superimposed over the preplanned implant positions to calculate the degree of angular deviation and position of placement. Adopting 5% alpha error and 80% study power in estimating sample size, a total of 88 implants were placed according to the all-on-4 concept in 22 mandibular laboratory casts. These were divided into 2 groups: with the newly fabricated surgical guide and with a traditional fully guided protocol. Deviations at the point of entry, at the apex horizontally, the vertical apical depth, and angular deviations from the proposed plan were measured from the superimposed scans. Differences in apical depth, horizontal deviation at the apex, and horizontal deviation in the hexagon measurements were compared with the independent t test, while differences in angular deviation were assessed with the Mann-Whitney U test (α=.05).

RESULTS

No statistically significant difference was found in the apical depth deviation (P>.05), but significant differences were found in the apex (P=.002), hexagon (P<.001), and angular deviation (P<.001) between the new guide and the traditional guide.

CONCLUSIONS

The new surgical guide showed potential for higher accuracy in implant placement when compared with the fully guided sleeveless surgical guide. In addition, it provided an undisturbed flow of irrigation around the drill throughout the drilling procedure, with the advantage of eliminating the special armamentarium usually required.

Influence of alveolar ridge morphology and guide-hole design on the accuracy of static Computer-Assisted Implant Surgery with two implant macro-designs: An in vitro study

OBJECTIVES

The primary aim of this in vitro study was to evaluate the influence of alveolar ridge morphologies on the accuracy of static Computer-Assisted Implant Surgery (sCAIS). The secondary aims were to evaluate the influence of guide-hole design and implant macro-design on the accuracy of the final implant position.

METHODS

Eighteen standardized partially edentulous maxillary models with two different types of alveolar ridge morphologies were used. Each model was scanned via cone beam computer tomography prior to implant placement and scanned with a laboratory scanner prior to and following implant placement using sCAIS. The postsurgical scans were superimposed on the initial treatment planning position to measure the deviations between planned and postsurgical implant positions.

RESULTS

Seventy-two implants were equally distributed to the study groups. Implants placed in healed alveolar ridges showed significantly lower mean deviations at the crest (0.36 ± 0.17 mm), apex (0.69 ± 0.36 mm), and angular deviation (1.86 ± 0.99°), compared to implants placed in fresh extraction sites (0.80 ± 0.29 mm, 1.61 ± 0.59 mm, and 4.33 ± 1.87°; all p<0.0001). Implants placed with a sleeveless guide-hole design demonstrated significantly lower apical (1.02 ± 0.66 mm) and angular (2.72 ± 1.93°) deviations compared to those placed with manufacturer's sleeves (1.27 ± 0.67 mm; p = 0.01, and 3.46 ± 1.9°; p = 0.02). Deep-threaded tapered bone level implants exhibited significantly lower deviations at the crest (0.49 ± 0.28 mm), apex (0.97 ± 0.63 mm), and angular deviations (2.63 ± 1.85°) compared to shallow-threaded parallel-walled bone level implants (0.67 ± 0.34 mm; p = 0.0005, 1.32 ± 0.67 mm; p = 0.003, and 3.56 ± 1.93°; p = 0.01).

CONCLUSIONS

The accuracy of the final implant position with sCAIS is determined by the morphology of the alveolar ridge, the design of the guide holes, and the macrodesign of the implant.

CLINICAL SIGNIFICANCE

Higher accuracy in the final implant position was observed with implants placed in healed alveolar ridge morphologies, in implants with deep-threaded tapered macro-design, and when sleeveless surgical guide holes were used.

Accuracy of keyless vs drill-key implant systems for static computer-assisted implant surgery using two guide-hole designs compared to freehand implant placement: an in vitro study

PURPOSE

This in vitro study aimed at comparing the accuracy of freehand implant placement with static computer-assisted implant surgery (sCAIS), utilizing a keyless and a drill-key implant system and two guide-hole designs.

METHODS

A total of 108 implants were placed in 18 partially edentulous maxillary models simulating two different alveolar ridge morphologies. 3D digital deviations between pre-planned and post-operative implant positions were obtained. Guide material reduction was assessed in the keyless implant system for the manufacturer's sleeve and sleeveless guide-hole designs.

RESULTS

sCAIS using a sleeveless guide-hole design demonstrated smaller mean angular, crestal and apical deviations compared to sCAIS utilizing a manufacturer's sleeve and the freehand group (2.6 ± 1.6°, vs 3.3 ± 1.9°, vs 4.0 ± 1.9°; 0.5 ± 0.3 mm, vs 0.6 ± 0.3 mm, vs 0.8 ± 0.3 mm; and 1.0 ± 0.5 mm, vs 1.2 ± 0.7 mm, vs 1.5 ± 0.6 mm). Smaller angular and apical mean deviations were observed in the keyless implant system as compared with the drill-key implant system (3.1 ± 1.7°, vs 3.5 ± 1.9°, p = 0.03; and 1.2 ± 0.6 mm, vs 1.4 ± 0.7 mm, p = 0.045). Overall, smaller angular, crestal, and apical deviations (p < 0.0001) were observed in healed alveolar ridges (2.4 ± 1.7°, 0.5 ± 0.3 mm, and 0.9 ± 0.5 mm) than in extraction sockets (4.2 ± 1.6°, 0.8 ± 0.3 mm, and 1.6 ± 0.5 mm). Higher mean volumetric material reduction was observed in sleeveless than in manufacturer's sleeve guide-holes (- 0.10 ± 0.15 mm³, vs - 0.03 ± 0.03 mm³, p = 0.006).

CONCLUSIONS

Higher final implant positional accuracy was observed in sCAIS for the keyless implant system, with a sleeveless guide-hole design, and in healed ridges. Sleeveless guide holes resulted in higher volumetric material reduction compared with the manufacturer's sleeve.

Influence of drilling sequence and guide-hole design on the accuracy of static computer-assisted implant surgery in extraction sockets and healed sites-An in vitro investigation

OBJECTIVES

To evaluate the effect of drilling sequence, guide-hole design, and alveolar ridge morphology on the accuracy of implant placement via static computer-assisted implant surgery (sCAIS).

MATERIALS AND METHODS

Standardized maxillary bone models including single-tooth gaps with fresh extraction sockets or healed alveolar ridge morphologies were evaluated in this study. Implants were placed using different drilling sequences (i.e., complete [CDS] or minimum [MDS]), and guide-hole designs (i.e., manufacturer's sleeve [MS] or sleeveless [SL] guide-hole designs). The time for implant placement via sCAIS procedures was also recorded. The angular, crestal, and apical three-dimensional deviations between planned and final implant positions were digitally obtained. Statistical analyses were conducted by a non-parametric three-way ANOVA (α = .05).

RESULTS

Based on a sample size analysis, a total of 72 implants were included in this study. Significantly higher implant position accuracy was found at healed sites compared to extraction sockets and in SL compared to MS guide-hole design in angular, crestal, and apical 3D deviations (p ≤ .048). A tendency for higher accuracy was observed for the CDS compared to the MDS, although the effect was not statistically significant (p = .09). The MDS required significantly shorter preparation times compared with CDS (p < .0001).

CONCLUSION

Implant placement via sCAIS resulted in higher accuracy in healed sites than extraction sockets, when using SL compared to MS guides, and tended to be more accurate when using CDS compared to MDS. Therefore, even though surgery time was shorter with MDS, its use should be limited to strictly selected cases.

Thermal changes during implant site preparation with a digital surgical guide and slot design drill: an ex vivo study using a bovine rib model

PURPOSE

In this study, we aimed to evaluate the degree of heat generation when a novel drill design with an irrigation slot was used with metal sleeve-free (MF) and metal sleeve-incorporated (MI) surgical guides in an environment similar to that of the actual oral cavity.

METHODS

A typodont with a missing mandibular right first molar and 21 bovine rib blocks were used. Three-dimensional-printed MF and MI surgical guides, designed for the placement of internal tapered implant fixtures, were used with slot and non-slot drills. The following groups were compared: group 1, MI surgical guide with slot drill; group 2, MI surgical guide with a non-slot drill; and group 3, MF surgical guide with a slot drill. A constant-temperature water bath at 36°C was used. The drilling was performed in 6 stages, and the initial, highest, and lowest temperatures of the cortical bone were measured at each stage using a non-contact infrared thermometer.

RESULTS

There were no temperature increases above the initial temperature in any drilling procedure. The only significant difference between the non-slot and slot groups was observed with the use of the first drill in the MI group, with a higher temperature in the non-slot group (P=0.012). When the heat generation during the first and the second drilling was compared in the non-slot group, the heat generation during the first drilling was significantly higher (P<0.001), and there was no significant difference in heat generation between the drills in the slot group.

CONCLUSIONS

Within the limitations of this study, implant-site preparation with the surgical guide showed no critical increase in the temperature of the cortical bone, regardless of whether there was a slot in the drill. In particular, the slotted drill had a cooling effect during the initial drilling.

Free-Hand versus Surgical Guide Implant Placement

One of the most key areas of dentistry is dental implant surgery. The use of digital equipment and software in dentistry has developed considerably in recent years compared to other fields of medicine. Since examining the advantages and disadvantages of each approach, along with case studies, can help physicians make informed decisions, this review study aims to raise the awareness of dentists to make easier decisions about using guided or free-hand surgery. When planning for a dental implant, one of the most challenging questions that doctors face is which method to use (guided surgery or free-hand). Choosing the right method, such as other clinical considerations, will depend on the individual circumstances of each patient and the preference of the treating physician. Free-hand surgery is a cost-effective method in which the flap is reflected, and, according to the doctor's diagnostic information, an implant is placed, which in many cases is a useful method. Guided surgery has the highest level of accuracy and control, in which osteotomy is designed and printed through a digital surgery guide, and depending on the complexity of the case and the patient's anatomy, it has a higher level of value than free surgery. The surgical guide helps the surgeon make the implant surgery more accurate, safer, simpler, at a lower cost, and in less time. In fact, there are patterns that convey information about the position of the tooth to the dentist before the implant is placed.

Precision and trueness of computer-assisted implant placement using static surgical guides with open and closed sleeves: An in-vitro analysis

Objectives

The aim of this in vitro study was to determine accuracy defined by trueness and precision of computer‐assisted implant surgery comparing two guided surgery kits designed for either closed sleeves or open sleeves with a lateral window.

Material and methods

Each n=20 implants were placed fully guided (sleeve‐bone distance of 2 or 4 mm) in identical replicas using a surgical guide with both closed sleeve or an open sleeve, partially guided, or free hand. The achieved implant position was digitized and compared with the planned position. Trueness and precision were determined. 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 and the Scheffé procedure.

Results

The accuracy of guided implant placement using closed and open sleeves was comparable when the sleeve‐bone distance was 2 mm. Accuracy decreased when the sleeve‐bone distance increased in both fully guided groups, more so in the open than in the closed sleeve group. The least accurate method was the free‐hand group. Partially guided implant surgery was more accurate than free‐hand placement, but less accurate than the fully guided groups with 2‐mm sleeve‐bone distance.

Conclusions

The closer the sleeve to the bone, the more accurate and precise is computer‐assisted implant surgery using a closed system and a system using open sleeves. Partially guided implant surgery using only the static guide for the pilot drill is less accurate than both fully guided approaches, but more accurate than free‐hand surgery.

Comparison of the accuracy of implant placement using different drilling systems for static computer-assisted implant surgery: A simulation-based experimental study

BACKGROUND

Different designs of surgical drilling systems have been developed for the purpose of static Computer-Assisted Implant Surgery (sCAIS), but there is at present little understanding of how design principles affect the accuracy of implant placement.

PURPOSE

The aim of this in vitro study was to compare the accuracy of implant placement among five drilling systems of sCAIS in a controlled experimental setting.

MATERIALS AND METHODS

Twenty-five 3D printed models with two edentulous bilateral premolar spaces were allocated to five different drilling systems: group A: sleeve-in-sleeve, group B: sleeve-in-sleeve with self-locking, group C: mounted sleeve-on-drill, group D: integrated sleeve-on-drill with metal sleeve in the guide, group E: integrated sleeve-on-drill without metal sleeve. Models were scanned with CBCT and optical scanner. All implants were digitally planned and 10 implants placed with sCAIS in each group. Postoperative 3D deviation of placed vs planned position was measured by means of platform, apex and angular deviation. Data was analyzed using Kruskal-Wallis test (P ≤ .05). Pairwise comparisons were tested with Dunn's test with adjusted P values.

RESULTS

The overall platform deviation ranged from 0.42 ± 0.12 mm (group B) to 1.18 ± 0.19 mm (group C). The overall apex deviation ranged from 0.76 ± 0.22 mm (group B) to 1.95 ± 0.48 mm (group D). The overall angular deviation ranged from 2.50 ± 0.89 degree (group B) to 5.30 ± 1.04 degree (group E). Group A and B showed significantly less angular deviation than groups D and E (P < .05). There was no statistically significant differences in all parameters between group A and B, as well as between group D and E (P > .05).

CONCLUSIONS

Significant differences were found with regards to accuracy among the five sCAIS systems tested, suggesting that the drilling protocol, the devices used and the design principles of the guides could influence the accuracy of implant placement.