A randomized controlled trial on the efficiency of free-handed, pilot-drill guided and fully guided implant surgery in partially edentulous patients

Accuracy of Two Robotic Computer-Aided Implant System Registration Methods for Dental Implantation: A Prospective Study

BACKGROUND

Robot-assisted implant surgery has been shown to achieve high levels of accuracy. However, there is currently a paucity of clinical studies evaluating the accuracy of marker-based intraoral scanner (IOS) registration (IR) methods.

PURPOSE

The purpose of this study was to compare the accuracy of the marker-based cone beam computed tomography (CBCT) registration (CR) method and the IR method in the dental implant in the robotic computer-aided implant system (R-CAIS).

MATERIALS AND METHODS

This retrospective study included 20 participants, with 10 undergoing implant surgery using the CR method within a robotic system, and the remaining 10 receiving implants using the IR method. Preoperative CBCT images used for implant planning were aligned with the postoperative CBCT images to assess and quantify positional deviations in implant placement. The primary outcome measures were FRE, entry deviation, apical deviation, and angular deviation. A Student's t-test was performed to compare differences between the two groups, with a p-value of < 0.05 considered statistically significant.

RESULTS

The mean ± standard deviation values for FRE were 0.027 ± 0.007 mm for the CR group and 0.031 ± 0.006 mm for the IR group (p = 0.149). The mean ± standard deviation values for entry deviation were 0.58 ± 0.11 mm for the CR group and 0.53 ± 0.15 mm for the IR group (p = 0.072). The mean ± standard deviation values for apical deviation were 0.52 ± 0.12 mm for the CR group and 0.50 ± 0.14 mm for the IR group (p = 0.730). The mean ± standard deviation values for apical deviation were 1.10 ± 0.34 mm for the CR group and 1.17 ± 0.23 mm for the IR group (p = 0.730).

CONCLUSIONS

In R-CAIS, the IR method demonstrated accuracy comparable to that of the CR method, with both methods yielding clinically satisfactory outcomes.

In vitro evaluation of six intraoral scanners for cone beam computed tomography data registration in robotic-assisted implant surgery: Impact of scanning experience

OBJECTIVES

This study evaluated the accuracy of intraoral scanning (IOS) and cone beam computed tomography (CBCT) data registration (ICR) in robotic computer-assisted implant surgery (r-CAIS) using six different intraoral scanners, considering the impact of surgeon experience.

METHODS

A total of 112 standardized mandibular partially edentulous models were assigned to six experimental groups and one control group based on the intraoral scanner used. In the control group, preoperative CBCT data were registered with CBCT data from a model containing an optical tracking marker (OT-Marker). In the experimental groups, IOS data from models with OT-Markers were registered with preoperative CBCT data. Each experimental group was further divided based on the surgeon's experience: one subgroup had a surgeon with over 5 years of IOS experience, while the other had a novice surgeon. Following registration, two implants were placed in each model using r-CAIS. Postoperative CBCT images were analyzed to measure and compare three-dimensional (3D) and two-dimensional (2D) deviations of implant positioning.

RESULTS

No significant differences were observed in angular, entry level, or apical deviations among the ICR methods using the six intraoral scanners (P > 0.05). However, different scanners found substantial variations in entry, apical, entry depth, and apical depth deviations (P < 0.05). Furthermore, no considerable differences were found in implant deviation indices between surgeons with different levels of scanning experience (P > 0.05).

CONCLUSION

The ICR method demonstrates high accuracy across six intraoral scanners, regardless of the surgeon's IOS experience. However, accuracy varies among scanners.

CLINICAL SIGNIFICANCE

This in vitro study provides valuable insights for surgeons in selecting an appropriate intraoral scanner for the ICR method. Moreover, it confirms that the method's accuracy is independent of the surgeon's experience, supporting its broader clinical adoption.

Freehand vs. computer-aided implant surgery: a systematic review and meta-analysis-part 1: accuracy of planned and placed implant position

OBJECTIVES

This systematic review aimed to investigate and compare the accuracy of free-hand and computer-aided implant surgery (CAIS) approaches in dental implant placement.

MATERIAL AND METHODS

The PICO question as follows: In patients receiving dental implants, does computer-aided implant surgery superior in accuracy compared to non-computer-aided implant surgery? The primary outcome was angular deviation between the planned and placed position of the implant. An electronic search was made to identify all relevant studies reporting the accuracy of CAIS approaches and freehand for dental implant placement. The data were extracted in the descriptive description, and a meta-analysis of single means was performed to estimate the deviations for each variable using a random-effects model.

RESULTS

Out of 1609 initial articles, 55 were selected for data extraction. The mean value of angular, entry, and apex deviations were 7.46°, 1.56 mm, and 2.22 mm for freehand, 5.94°, 1.13 mm, and 1.43 mm for pilot drill-sCAIS, 2.57°, 0.72 mm, 0.88 mm for fully guided-sCAIS (fg-sCAIS), and 3.67°, 1.01 mm, and 1.36 for dynamic CAIS (dCAIS), respectively. Significant differences were found between the freehand and CAIS approaches (p < 0.04). Fg-sCAIS was significantly more accurate than dCAIS systems at the entry (p < 0.001).

CONCLUSIONS

Compared to the freehand approach, both sCAIS and dCAIS improve implant placement accuracy, with angular deviations ranging from 2° to 6°. Detailed planning is crucial for CAIS, particularly for fg-sCAIS, which demonstrated the highest accuracy than others. As apex deviations of 1 to 2 mm have been observed in CAIS approaches, a 2-mm safety margin should be implemented to minimize surgical risks.

Influence of guide support on the accuracy of static Computer-Assisted Implant Surgery (sCAIS) in partially edentulous cases using a keyless guiding system: an in vitro study

PURPOSE

To evaluate the influence of guide support on the accuracy of sCAIS using a keyless guiding system in different cases of partial edentulism.

METHODS

Sixty polyamide models of partially edentulous maxillae, simulating anterior and posterior single-tooth gaps as well as anterior and distal extended edentulous areas, were fabricated. Full-arch, 2-teeth, and 4-teeth supported surgical guides were used to place implants at FDI 15, 17, 21, 26 sites in Model A and at FDI 12, 22, 15 sites in Model B. In total, 210 replica implants were placed using 120 surgical guides in seven implantation sites. Three-dimensional crestal and apical, angular and vertical deviations from the planned implant positions were compared using the Kruskal-Wallis H test with Dunn's procedure for multiple pairwise comparisons.

RESULTS

Overall median 3D crestal and apical deviations of implants placed with 2-teeth guide support (0.62 mm [0.45-0.84], 0.92 mm [0.69-1.25]) and 4-teeth guide support (0.65 mm [0.52-0.81], 1.01 mm [0.8-1.26]) were significalty lower compared to the full-arch support group (0.86 mm [0.63-0.98], 1.26 mm [0.98-1.52]) with values of p < 0.017. Overall angular and vertical deviations of implants placed with 2-teeth guide support (2.61° [1.71-3.75], 0.32 mm [0.15-0.44]) were significantly lower compare to the full-arch support group (3.22° [2.25-4.41], 0.46 mm [0.24-0.62]). In the subgroup analysis, implants placed at the FDI 12, 22, and 15 positions exhibited significantly higher 3D and angular deviations with full-arch guide support, whereas the 3D apical and angular deviations of were significantly lower with 2-teeth guide support at the FDI 21 site.

CONCLUSIONS

The deviations in all guide support groups did not exceed the recommended safety margins. Statistically significant differences were found between guide support groups, with influence of guide support on the accuracy of sCAIS varying across different implantation sites.

TRIAL REGISTRATION

Not applicable.

The Influence of Guiding Concept on the Accuracy of Static Computer-Assisted Implant Surgery in Partially Edentulous Cases: An In Vitro Study

Background and Objectives: Static Computer-Assisted Implant Surgery (sCAIS) can be performed with different drill guiding systems. This study aimed to compare the accuracy of two guiding concepts of sCAIS in partially edentulous cases. Materials and Methods: Forty polyamide models of partially edentulous maxillae with seven implantation sites were fabricated. In total, 140 replica implants were placed with keyless (KL) and drill-key (DK) guiding systems using static, full-arch, tooth-supported surgical guides. Three-dimensional crestal and apical, angular and vertical deviations from the planned implant positions were compared using Mann-Whitney U and Kruskal-Wallis H tests. Intergroup homogeneity of variance homogeneity was examined using Levene's test to assess the precision. Results: Overall median 3D crestal and apical deviations of implants placed in the KL group were significantly higher compared to the DK group (0.86 mm [0.63-0.98] vs. 0.72 mm [0.52-0.89], p = 0.006 and 1.26 [0.98-1.52] vs. 1.13 [0.70-1.45], p = 0.012). In the subgroup analysis, implants placed with a KL system showed higher 3D crestal (p = 0.029), 3D apical (p < 0.001) and angular (p < 0.001) deviations in the extended anterior area, higher 3D crestal (p < 0.001) deviations in the proximal posterior single-tooth gap and higher vertical (p < 0.001) deviations in the distal site of free-end situation. Contrarily, the KL group showed lower 3D crestal (p = 0.007), 3D apical (p < 0.001), angular (p < 0.001) and vertical (p = 0.003) deviations in the distal posterior single-tooth gap, lower 3D apical (p = 0.007) and angular (p = 0.007) deviations in the distal site of free-end situation and lower vertical (p = 0.019) deviations in the proximal site of free-end situation. Conclusions: The deviations of both guiding concepts did not exceed the recommended safety margins. Statistically significant differences in deviations were found between two guiding concepts. Guiding concepts with superior accuracy varied across different sites of implantation.

Accuracy of Static Computer-Assisted Implant Placement in Narrow Ridge by Novice Clinicians

OBJECTIVE

 This study aimed to evaluate the accuracy and clinical impact of implant placement by novice implant clinicians in the narrow anterior ridge by fully guided (FG), pilot-guided (PG), and freehand (FH) placements.

MATERIALS AND METHODS

 A maxillary surgical model with missing incisors and a narrow ridge was designed. Two implants were planned in the lateral incisor locations to receive screw-retained implant prosthesis. Fifteen novice implant clinicians placed implants according to every placement. Angle, vertical and horizontal platform, and horizontal apex deviations from the planned implant were measured. The clinical impact evaluation aimed to relate the position of each placed implant to (1) periimplant bone dimension after implant placement and (2) the prosthesis retention mechanism.

RESULTS

 The FG implants were more accurate than PG implants at the angle (p = 0.001) and maximum horizontal apex deviations (p = 0.001), and were more accurate than FH implants for all comparisons (p = 0.001). The PG implants were superior to FH implants at the maximal horizontal platform deviation (p = 0.001). All FG implants were fully covered with bone and could be restored with screw-retained prostheses. One PG implant (3.3%) had fenestration at the apex, and one PG implant (3.3%) could not be restored with screw-retained prosthesis. Seven FH implants (23.3%) had fenestration at the apex, and one FH implant (3.3%) suffered from dehiscence. Seven FH implants (23.3%) were not restorable with screw-retained prosthesis.

CONCLUSION

 For novice clinicians, a significantly greater accuracy was observed for FG placement, followed by PG and FH placements. FH implants experienced significant compromise of periimplant bone dimension and the prosthesis retention mechanism.

Influence of supporting teeth quantity of surgical guide on the accuracy of the immediate implant in the maxillary central incisor: an in vitro study

INTRODUCTION

Guided surgery for immediate anterior implants aims to reduce the time required for aesthetic and functional immediate loading. However, the limited surface area of anterior teeth for guide stabilization may affect the accuracy of implant positioning. This in vitro study evaluated the effect of the number of supporting teeth on the accuracy of immediate implants in the maxillary central incisor region.

METHODS

28 replica implants were inserted into 28 upper jaw models, simulating immediate post-extraction sockets of tooth 11. Based on the number of supporting teeth, the implants were categorized into G1 (four adjacent teeth) and G2 (six adjacent teeth). The planned and actual implant positions were compared using the evaluation module of the implant planning software. Angular and 3D deviations were measured as the primary outcomes. Statistical analysis was performed using the two-sample t-test, with p-values less than 0.05 defined as statistically significant.

RESULTS

Between group G1 and G2, angular deviation was measured at 4.63 ± 0.71° and 3.59 ± 0.97°, respectively, while the implant apex 3D deviation was 2.08 ± 0.21 mm for G1 and 1.40 ± 0.27 mm for G2. These differences were statistically significant (p = 0.003 and p < 0.001, respectively). Other discrepancy variables in G2 demonstrated lower values but were not statistically significant compared to G1.

CONCLUSION

The number of supporting teeth for the surgical guide can influence the accuracy of immediate implant surgery. While both four-teeth and six-teeth supports demonstrated acceptable clinical implant accuracy, a surgical guide supported by six teeth can enhance implant precision.

Analysis of trends in the context of implant therapy in a university surgical specialty clinic: a 20-year retrospective study

OBJECTIVES

To analyze the trends in the context of implant therapy in a 3-year patient population and compare it with data obtained over the last 20 years.

MATERIALS AND METHODS

All adult subjects who received treatment in the context of implant therapy between 2020 and 2022 were included in this retrospective study. Data regarding patient demographics, indications and location of implant therapy, implant characteristics, surgical techniques, complications, and early implant failures were recorded and compared to data obtained in the years 2002-2004, 2008-2010, and 2014-2016.

RESULTS

Between 2020 and 2022, n = 1555 implants were placed in n = 1021 patients. The mean age at implant placement was 59.9 + 15.1 years, demonstrating an increase over time in the age group 61-80 years of 23.1% and > 80 years of 3.2% (p < 0.0001). Single tooth gaps (48.9%) remained the main indication. The use of narrow diameters ≤ 3.5 mm increased (9.4% vs. 26.6%, p < 0.0001), while implant lengths > 10 mm decreased (45.7% vs. 23.5%, p < 0.0001). A reduction in more invasive techniques and an increase in computer-assisted implant surgeries (CAIS) of 19.5% was found.

CONCLUSIONS

The mean age of patients receiving dental implant therapy, with the use of narrow-diameter and shorter implants has progressively increased in the last 20 years. The observed trends suggest a transition from conventional to CAIS, accompanied by the introduction of minimally invasive surgical techniques.

CLINICAL RELEVANCE

The adoption of narrower and shorter implants, along with minimally invasive techniques and CAIS, enables clinicians to tailor treatment plans that accommodate the unique needs of aging patients and optimize clinical outcomes.

Effect of immediate all-digital restoration of single posterior implants: The SafetyCrown concept on patient-reported outcome measures, accuracy, and treatment time-A randomized clinical trial

OBJECTIVE

The SafetyCrown workflow facilitates the immediate restoration of posterior single sites with the one-abutment/one-time concept. This randomized clinical trial aimed to assess the direct effect of immediate restoration on dental patient-reported outcomes (dPROs), feasibility, implant accuracy, and time.

MATERIALS AND METHODS

Participants with a single posterior edentulous site for late implant placement underwent optical impressions, shade selection, and cone beam computed tomography. After virtual treatment planning, they were randomized into the test group and the control group. For the test group, individual definitive hybrid abutments were prefabricated. The next step was a fully guided surgery with printed guides. After the implant was placed using guided surgery, the abutment was inserted. A chairside CAD/CAM workflow was used to provide the patient with a provisional restoration. Implants in the control group were left submerged to heal. Oral health-related quality of life (OHRQoL) was assessed using the OHIP-G14, and dPRO was measured using a 10-item visual analog scale (VAS) questionnaire. Additional measurements of implant accuracy and time were performed. Follow-up was performed 7 to 10 days after implant placement.

RESULTS

Thirty-nine participants with 45 restorations were included (test group: 23, control: 22). Immediate restoration was successful in 21 out of 23 implants (91.3%) in the test group. Both groups exhibited decreased OHRQoL without significant intergroup differences, while patient satisfaction was high overall. Test group participants perceived higher benefits and satisfaction with immediate loading than participants in the control group. Implant accuracy averaged 0.60 mm at the shoulder and 0.95 mm at the apex. Operative time was longer in the immediate loading group (61.9 min) than in the control group (32.1 min) (p < 0.001).

CONCLUSIONS

Considering the limitations, the immediate restoration of late placed posterior implants using the described workflow proved feasible in 21 out of 23 cases. Both groups achieved high patient satisfaction with no differences in OHRQoL during the first week. Patients who received immediate loading rated the benefits very highly and were satisfied with the provisional restoration during the healing period.

Comparative analysis of dental implant placement accuracy: Semi-active robotic versus free-hand techniques: A randomized controlled clinical trial

BACKGROUND

Robot-assisted implant surgery has emerged as a novel digital technology, and the accuracy need further assessment.

PURPOSE

This study aimed to compare the accuracy of single dental implant placement between a novel semi-active robot-assisted implant surgery (RAIS) method and the conventional free-hand implant surgery (FHIS) method through a multicenter, randomized controlled clinical trial.

MATERIALS AND METHODS

Patients requiring single dental implant placement were recruited and randomized into RAIS and FHIS group. Deviations at the platform, apex, and angle between the planned and final implant positions were assessed in both groups. Additionally, the evaluation of instrument and surgical complications was examined.

RESULTS

A total of 140 patients (median age: 35.35 ± 12.55 years; 43 males, 97 females) with 140 implants from four different research centers were included, with 70 patients (70 implants) in the RAIS group and 70 patients (70 implants) in the FHIS group. In the RAIS and FHIS groups, the median platform deviations were 0.76 ± 0.36 mm and 1.48 ± 0.93 mm, respectively (p < 0.001); median apex deviations were 0.85 ± 0.48 mm and 2.14 ± 1.25 mm, respectively (p < 0.001); and median angular deviations were 2.05 ± 1.33° and 7.36 ± 4.67°, respectively (p < 0.001). Similar significant difference also presented between RAIS and FHIS group in platform vertical/horizontal deviation, apex vertical/horizontal deviation. Additionally, implants with self-tapping characteristics exhibited significantly larger deviations compared with those without self-tapping characteristics in the RAIS group. Both RAIS and FHIS methods demonstrated comparable morbidity and safety pre- and post-operation.

CONCLUSIONS

The results indicated that the RAIS method demonstrated superior accuracy in single dental implant placement compared with the FHIS method. Specifically, RAIS exhibited significantly smaller deviations in platform, apex, and angular positions, as well as platform and apex vertical/horizontal deviations. This clinical trial was not registered prior to participant recruitment and randomization. https://www.chictr.org.cn/showproj.html?proj=195045.

Ten-Year Follow-Up of Oral Implants in Bone With Limited Bucco-Oral Dimensions: A Prospective Case Series

BACKGROUND

It has been suggested that 1-2 mm of bone width at the buccal and lingual aspect is required for a successful long-term implant outcome. Low levels of evidence support this minimum threshold of bone width. This prospective study aimed at evaluating the outcome of implants placed in alveolar ridges with limited bucco-oral dimensions.

MATERIALS AND METHODS

One-hundred implants (dia. 3.5 mm) were placed in 28 patients with narrow alveolar ridge dimensions (<4.5 mm width) without augmentation procedures and conventionally loaded. Intra-oral radiographs were taken at implant placement and abutment connection and at 1, 2, 3, 5 and 10 years of follow-up. At the 10-year follow-up (21 patients; 75 implants), full-mouth periodontal charting was performed, and the peri-implant keratinized tissue width and attachment type were recorded. Two calibrated periodontists analysed the peri-implant bone changes.

RESULTS

After 10 years, all implants showed successful osseointegration and a cumulative survival rate of 100%. The implants were placed 0.85 mm ± 0.89 mm subcrestally. After 10 years, the marginal bone was located 1.59 ± 2.11 mm apical to the implant shoulder. Throughout this period of follow-up, the mean annual marginal bone loss was 0.094 mm. Furthermore, 84% of implants in 72% of patients presented with bleeding on probing.

CONCLUSION

After 10 years of functional loading, implants placed in alveolar ridges with limited bucco-oral dimensions (≤4.5 mm) exhibited only minimum marginal bone loss.

Reducing the risk of tooth injury in anterior maxillary interdental osteotomy for cleft lip and palate patients using a surgical navigation technique

The aim of this study was to investigate the clinical feasibility of preventing tooth injury from anterior maxillary interdental osteotomy by using a surgical navigation technique. A retrospective review was conducted on cleft lip and palate patients treated with anterior maxillary osteotomy followed by distraction osteogenesis between August 2019 and May 2022. Patients operated on through image guidance were enrolled in the navigation group, while those who were operated on freehand were enrolled in the freehand group. Tooth injuries were identified on postoperative images. Linear and angular deviations of the osteotomy line were measured. Twelve patients were enrolled in the study, seven in the navigation group and five in the freehand group. Altogether, 24 osteotomy lines and 53 adjacent teeth were evaluated. The dental injury rate was 3% in the navigation group and 27% in the freehand group (P = 0.016). The average linear deviations (mean ± standard deviation) were 0.67 ± 0.30 mm and 2.05 ± 1.33 mm, respectively (P < 0.001), while the average angular deviations were 1.67 ± 0.68° and 11.41 ± 7.46°, respectively (P < 0.001). The results suggest that navigation was able to reduce the tooth injury risk compared with freehand interdental osteotomies in crowded dental arches.

Digital versus conventional surgical guide fabrication: A randomized crossover study on operator preference, difficulty, effectiveness, and operating time

AIM

If surgical guide fabrication is introduced in a dental education program, a digital and conventional workflow can be used. This study evaluated operator preference, perceived difficulty and effectiveness and operating time of both fabrication methods.

MATERIALS AND METHODS

Forty participants in a university setting (students, n = 20; dentists, n = 20) with varying levels of dental experience, but no experience in surgical guide fabrication, were randomly assigned to consecutively fabricate surgical guides on a standardized training model, with either the digital or conventional workflow first. The operating time was measured, and operator preference and the perception of difficulty and effectiveness were assessed with a questionnaire. T tests were used for statistical analysis (α = .05).

RESULT

Of the students, 95% preferred the digital workflow and of the dentists 70%. The perceived difficulty of the digital workflow was significantly lower than the conventional workflow in the student group. Both groups perceived the digital workflow to be more effective. The mean operating time (mm:ss) amounted 12:34 ± 2:24 (students) and 18:07 ± 6:03 (dentists) for the digital, and 22:20 ± 3:59 (students) and 20:16 ± 4:03 (dentists) for the conventional workflow.

CONCLUSION

Both students and dentists prefer the digital workflow for surgical guide fabrication. Students perceive the digital workflow as less difficult and more effective than the conventional workflow. The operating time for surgical guide fabrication is shorter with a digital workflow. This study indicates that digital fabrication techniques for surgical guides are preferred to be incorporated into the dental curriculum to teach students about treatment planning in implant dentistry.

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.

Dynamic Implant Surgery-An Accurate Alternative to Stereolithographic Guides-Systematic Review and Meta-Analysis

(1) Background: Dynamic guided surgery is a computer-guided freehand technology that allows highly accurate procedures to be carried out in real time through motion-tracking instruments. The aim of this research was to compare the accuracy between dynamic guided surgery (DGS) and alternative implant guidance methods, namely, static guided surgery (SGS) and freehand (FH). (2) Methods: Searches were conducted in the Cochrane and Medline databases to identify randomized controlled clinical trials (RCTs) and prospective and retrospective case series and to answer the following focused question: "What implant guidance tool is more accurate and secure with regard to implant placement surgery?" The implant deviation coefficient was calculated for four different parameters: coronal and apical horizontal, angular, and vertical deviations. Statistical significance was set at a p-value of 0.05 following application of the eligibility criteria. (3) Results: Twenty-five publications were included in this systematic review. The results show a non-significant weighted mean difference (WMD) between the DGS and the SGS in all of the assessed parameters: coronal (n = 4 WMD = 0.02 mm; p = 0.903), angular (n = 4 WMD = -0.62°; p = 0.085), and apical (n = 3 WMD = 0.08 mm; p = 0.401). In terms of vertical deviation, not enough data were available for a meta-analysis. However, no significant differences were found among the techniques (p = 0.820). The WMD between DGS and FH demonstrated significant differences favoring DGS in three parameters as follows: coronal (n = 3 WMD = -0.66 mm; p =< 0.001), angular (n = 3 WMD = -3.52°; p < 0.001), and apical (n = 2 WMD = -0.73 mm; p =< 0.001). No WMD was observed regarding the vertical deviation analysis, but significant differences were seen among the different techniques (p = 0.038). (4) Conclusions: DGS is a valid alternative treatment achieving similar accuracy to SGS. DGS is also more accurate, secure, and precise than the FH method when transferring the presurgical virtual implant plan to the patient.

Accuracy of Computer-Guided Implantology with Pilot Drill Surgical Guide: Retrospective 3D Radiologic Investigation in Partially Edentulous Patients

Background and Objectives: Implant placement with static navigation enables the reaching of a correct position of implants from an anatomical and prosthetic point of view. Different approaches of static navigation are described in the scientific literature, and the pilot-guided approach is one of the least investigated. The aim of the present study is the evaluation of the accuracy of implant insertion using a pilot drill template. Materials and Methods: Fifteen partially edentulous patients, requiring an implant rehabilitation of at least one implant, were enrolled. Pre- and post-operative low-dose CTs were acquired to measure the differences between final positions of implants and virtually planned ones. Three linear discrepancies (coronal, apical, and depth), two angular ones (bucco-lingual and mesio-distal), and the imprecision area were evaluated. Correlations between accuracy and rehabilitated jaws, sectors, and implant length and diameters were also analyzed. Results: Forty implants were inserted in fifteen patients using pilot drill templates. Mean coronal deviation was 1.08 mm, mean apical deviation was 1.77 mm, mean depth deviation was -0.48 mm, mean bucco-lingual angular deviation was 4.75°, and mean mesio-distal one was 5.22°. The accuracy was statistically influenced only by the rehabilitated jaw for coronal discrepancy and sectors and implant diameter for bucco-lingual angular deviations. Conclusions: The pilot drill template could represent a predictable solution to obtain a correct implant placement. Nonetheless, a safety margin of at least 2 mm should be respected during implant planning to prevent damages to anatomical structures. Therefore, the tool is helpful in order to prosthetically drive the implants; still, great attention must be paid in fully relying on this procedure when approaching dangerous structures such as nerves and vessels.

Performance of novice versus experienced surgeons for dental implant placement with freehand, static guided and dynamic navigation approaches

Lack of evidence exists related to the investigation of the accuracy and efficacy of novice versus experienced practitioners for dental implant placement. Hence, the following in vitro study was conducted to assess the accuracy of implant positioning and self-efficacy of novice compared to experienced surgeons for placing implant using freehand (FH), pilot drill-based partial guidance (PPG) and dynamic navigation (DN) approaches. The findings revealed that DN significantly improved the angular accuracy of implant placement compared with FH (P < 0.001) and PPG approaches (P < 0.001). The time required with DN was significantly longer than FH and PPG (P < 0.001), however, it was similar for both novice and experienced practitioners. The surgeon's self-confidence questionnaire suggested that novice practitioners scored higher with both guided approaches, whereas experienced practitioners achieved higher scoring with PPG and FH compared to DN. In conclusion, implant placement executed under the guidance of DN showed high accuracy irrespective of the practitioner's experience. The application of DN could be regarded as a beneficial tool for novices who offered high confidence of using the navigation system with the same level of accuracy and surgical time as that of experienced practitioners.

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.

Can computer-assisted implant surgery improve clinical outcomes and reduce the frequency and intensity of complications in implant dentistry? A critical review

Computer-assisted implant surgery (CAIS), either static or dynamic, is well documented to significantly improve the accuracy of implant placement. Whether the increased accuracy leads to a corresponding improvement in clinical outcomes has not yet been systematically investigated. The aim of this critical review was to investigate whether the use of CAIS can lead to reduction of complications as well as improved clinical and patient-reported outcomes (PROs) when compared with conventional freehand implant surgery. A comprehensive online search was conducted to identify studies where implants were installed with static computer-assisted implant surgery (s-CAIS)or dynamic computer-assisted implant surgery(d-CAIS) or combinations of the two, either compared with conventional free-hand implant placement or not. Seventy-seven studies were finally included in qualitative analysis, while data from three studies assessing postsurgical pain were suitable for a meta-analysis. Only a small number of the available studies were comparative. The current evidence does not suggest any difference with regard to intraoperative complications, immediate postsurgical healing, osseointegration success, and survival of implants placed with CAIS or freehand protocols. Intraoperative and early healing events as reported by patients in randomized clinical trials (RCTs) did not differ significantly between CAIS used with flap elevation and conventional implant placement. There is limited evidence that increased accuracy of placement with CAIS is correlated with superior esthetic outcomes. Use of CAIS does not significantly reduce the length of surgeries in cases of single implants and partially edentulous patients, although there appears to be a more favorable impact in fully edentulous patients. Although CAIS alone does not seem to improve healing and the clinical and PRO, to the extent that it can increase the utilization of flapless surgery and predictability of immediacy protocols, its use may indirectly lead to substantial improvements in all of the above parameters.

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.

Duration, deviation and operator's perception of static computer assisted implant placements by inexperienced clinicians

INTRODUCTION

This study measured the duration, deviation and operator's perception of implant placement by fully guided (FG), pilot-guided (PG) and freehand (FH) protocols by postgraduate students with minimal implant experience.

MATERIALS AND METHODS

Twenty postgraduate students participated in the study. Half of them placed single anterior (S-Ant) and single posterior (S-Post) implants, and the other half placed anterior (B-Ant) and posterior (B-Post) implants in a wide edentulous area. The PG placement involved surgical guides that only controlled pilot drilling, whilst the FG placement controlled all the drilling steps and implant placement. The duration of implant placement and the operator's perception (ease of drilling, ease of implant placement and operator's preference) were measured. The deviations of placed implants were quantified by measuring the trueness and angulation deviations in relation to the planned implants.

RESULTS

The PG placement was the quickest for inserting implants, followed by FG and FH placements, respectively (p < .05). The location of the implant had influenced the duration of implant placement only for the PG placement. In relation to ease of drilling, ease of implant placement and operator's preference, there was no significant difference amongst the different placement protocols or implant locations. The FG placement was associated with least deviations, followed by PG and FH placements, respectively (p < .05).

CONCLUSIONS

In the hands of postgraduate students with minimal implant experience, FG and PG placements reduced the implant placement duration in comparison with FH placement. The FG placement was consistently more accurate followed by PG placement.

Accuracy of commercial 3D printers for the fabrication of surgical guides in dental implantology

OBJECTIVES

To evaluate the accuracy of two different surgical guides (small extent = single implant and large extent = full arch) fabricated by five additive manufacturing technologies (SLA=Stereolithography, DLP= Digital Light Processing, FDM=Fused Deposition Modeling, SLS=Selective Laser Sintering, Inkjet).

METHODS

Overall, 72 guides (6 per type) were obtained with the different machines (SLA=Form2; DLP=Rapid Shape D40 and Cara Print 4.0; FDM=Raise 3D Pro2; SLS=Prodways P1000; Polyjet®=Stratasys J750). The guides were surface-scanned with an optical dental scanner, and the resulting files were compared with the initial design files using a surface matching software. Root Mean Square (RMS) and standard deviation were calculated, representing respectively trueness and precision. Kruskall-Wallis non-parametric test was used to compare trueness and precision between small-extent and large-extent guides and 3D printer by pairs. The threshold for significance was α=0.05, except for the comparison of printers by pairs where a Bonferroni-corrected level of 0.0033 was used.

RESULTS

Significant differences were observed for trueness and precision between small-extent and large-extent guides, regardless the printer except for DLP (trueness and precision) and SLS (precision). SLA, DLP and Polyjet® technologies showed similar results in terms of trueness and precision for both small-extend and large-extend guides (P>0.05).

CONCLUSIONS

The size affected the accuracy of CAD-CAM surgical guides. The different additive manufacturing technologies had a limited impact on the accuracy.

CLINICAL SIGNIFICANCE

This study is of clinical interest as it shows that the 3D printing technology (SLA/DLP) has a limited impact on 3D printed surgical guides accuracy. However, the size of the guide can have a significant impact, as small-extent guides were more accurate than large-extent guides.

Accuracy of static fully guided implant placement in the posterior area of partially edentulous jaws: a cohort prospective study

OBJECTIVE

A cohort prospective study was conducted to assess the three-dimensional positioning accuracy of the implant between pre-surgical and the final implant position using a static fully guided approach in the posterior area of the jaws.

MATERIALS AND METHODS

A total of 60 implants (30 patients) were digitally analyzed after superimposing the Digital Imaging and Communications in Medicine (DICOM) files obtained from the Cone Beam Computed Tomography (CBCT) pre- and post-implant placement. The software calculations included deviations at the implant shoulder and at the implant apex, global deviation (3D offset), and angle deviation. Statistical analysis was performed with α = 0.05.

RESULTS

Considering the total number of implants, mesiodistal, buccolingual, and apicocoronal mean deviations at the shoulder and implant apex were equal or below 0.21 ± 0.69 mm, and only the buccolingual mean deviation at the apex reached up to 0.67 ± 1.06 mm. The mesiodistal and apicocoronal deviations were not statistically significant at both the shoulder and apex levels of the implant. The mean total angular deviation was 5.62° ± 4.09. The main limitation of this surgical approach was the requirement for a wide mouth opening.

CONCLUSIONS

Static fully guided surgery for dental implant placement exhibits minimum deviations respect to presurgical planning. The main limitation in the posterior areas is the requirement for a wide mouth opening.

CLINICAL RELEVANCE

Even with minimum deviations clinically acceptable, precautions and safety margins must be respected when using static full-guided surgery to place dental implants.

Time and costs related to computer-assisted versus non-computer-assisted implant planning and surgery. A systematic review

Aim

To study the time and costs involved with computer‐assisted versus non‐computer‐assisted implant planning and placement.

Material and methods

Based on the PICO question, “In patients receiving dental implants, is computer‐assisted implant planning and surgery (CAIPS) compared to non‐computer‐assisted implant planning and surgery (non‐CAIPS) beneficial in terms of treatment related costs and time involved?”, a search path was created to perform an electronic search in the databases PubMed, PubMed Central, EMBASE, and Cochrane. The publication period of eligible publications extended from 01.01.2005 to 04.05.2020. Four independent reviewers reviewed the literature to identify studies that met the eligibility inclusion criteria. A further manual search of articles was performed, and gray literature was excluded. Corresponding authors of potentially eligible manuscripts were contacted for further information.

Results

Of the 1354 retrieved titles after the search were screened. Thirty‐one articles have been identified to read the full text, resulting in four articles to be analyzed for the present review all of which were RCTs. In total, 182 partially and completely edentulous patients were treated with 416 implants following either non‐computer‐assisted or computer‐assisted implant planning and surgery to determine the duration of the single working steps and the financial aspects of the different procedures.

Conclusions

When evaluating the time and costs involved with the diagnostic and planning procedures in computer‐assisted implant planning and surgery workflow protocols, one can summarize that these are higher than in the non‐computer‐assisted workflow protocols. The time involved with the procedures appears to be the driving factor when it comes to economic considerations. On the basis of the conclusions, also the time for the prosthetic restoration should be taken into account.

Three-dimensional accuracy of partially guided implant surgery based on dental magnetic resonance imaging

OBJECTIVES

To measure in vivo 3D accuracy of backward-planned partially guided implant surgery (PGIS) based on dental magnetic resonance imaging (dMRI).

MATERIAL AND METHODS

Thirty-four patients underwent dMRI examinations. Tooth-supported templates were backward planned using standard dental software, 3D-printed, and placed intraorally during a cone beam computed tomography (CBCT) scan. Treatment plans were verified for surgical viability in CBCT, and implants were placed with guiding of the pilot drill. High-precision impressions were taken after healing. The 3D accuracy of 41 implants was evaluated by comparing the virtually planned and definitive implant positions with respect to implant entry point, apex, and axis. Deviations from the dMRI-based implant plans were compared with the maximum deviations calculated for a typical single implant.

RESULTS

Twenty-eight implants were placed as planned in dMRI. Evaluation of 3D accuracy revealed mean deviations (99% confidence intervals) of 1.7 ± 0.9mm (1.2-2.1mm) / 2.3 ± 1.1mm (1.8-2.9 mm) / 7.1 ± 4.8° (4.6-9.6°) for entry point / apex / axis. The maximum deviations calculated for the typical single implant surpassed the upper bounds of the 99% CIs for the apex and axis, but not for the entry point. In the 13 other implants, dMRI-based implant plans were optimized after CBCT. Here, deviations between the initial dMRI plan and definitive implant position were only in part higher than in the unaltered group (1.9 ± 1.7 mm [0.5-3.4 mm] / 2.5 ± 1.5 mm [1.2-3.8 mm] / 6.8 ± 3.8° [3.6-10.1°] for entry point / apex / axis).

CONCLUSIONS

The 3D accuracy of dMRI-based PGIS was lower than that previously reported for CBCT-based PGIS. Nonetheless, the values seem promising to facilitate backward planning without ionizing radiation.

Multivariate analysis of causal factors influencing accuracy of guided implant surgery for partial edentulism: a retrospective clinical study

Abstract

Background

In dental implant treatment, the placement position of the implant body is important. The hypothesis is that there are factors that have a greater impact than the factors that have been studied so far.

Material and Methods

The deviation between planned and actually placed implants was measured three-dimensionally by modified treatment evaluation method in 110 patients who underwent implant placement with guided surgery for partial edentulism. Ten factors that seemed to affect errors in placement were selected: the type of tooth, type of edentulism, distance from the remaining teeth, the type of implant, implant length, number of implants, method of guidance, the number of teeth supporting the surgical guide, number of anchor pins, and presence or absence of a reinforcement structure. The effect of each factor that corrected each confounding was calculated using multivariate analysis.

Results

In this study, 188 implant bodies were set to target, and the errors measurement data of the implant position were as follows: average Angle, 2.5 ± 1.6° (95% CI 2.25–2.69); Base, 0.67 ± 0.37 mm (95% CI 0.62–0.72); and Apex, 0.92 ± 0.47 mm (95% CI 0.86–0.98). As the result of multivariate analysis, larger errors were present in the partially guided group than the fully guided group. The number of teeth supporting the surgical guide significantly influenced the error in placement position. The error caused by the number of anchor pins was significantly different for the Angle. Similarly, the presence of the reinforcement structure influenced the error significantly for the Angle.

Conclusions

It was suggested that the smaller errors could be present by performing guided surgery with full guidance and devising the design of the guide such as the number of teeth supporting the surgical guide, the setting of the anchor pin, and the reinforcement structure.

Accuracy of static computer-assisted implant placement in long span edentulous area by novice implant clinicians: A cross-sectional in vitro study comparing fully-guided, pilot-guided, and freehand implant placement protocols

BACKGROUND

To ensure accurate implant placement, surgical guides are used to control the steps of implant placement surgery.

PURPOSE

Evaluation of the accuracy of implant placement in long span edentulous area by novice implant clinicians according to fully-guided (FG), pilot-guided (PG), and freehand (FH) placement protocols.

MATERIALS AND METHODS

Maxillary surgical models with four missing teeth from the right first canine to the first molar were produced by 3-dimensional printing. Fourteen clinicians new to implant dentistry participated in the study, and each one of them inserted one canine and one molar implant for every implant placement protocol. All implant placement steps were completed in phantom heads to simulate the clinical situation. To evaluate the accuracy, the implant vertical, horizontal platform, horizontal apex, angle, and interimplant distance deviations from the planned positions were calculated.

RESULTS

With the exception of vertical deviation, the FG placement was clearly more accurate than the PG and FH placements for all the variables for canine and molar implants. The PG placement was significantly more accurate than the FH placement for the horizontal platform and apex deviations, and interimplant distance deviation. The FG placement did not show a significant impact of the location of the implant, or the horizontal deviations of the platform or the apex. The PG and FH placements showed increased deviation at the canine implant than the molar implant, and at the apex of the implants than the platform of the implants.

CONCLUSIONS

Within the limitations of this in vitro study, novice clinicians achieved a significantly more accurate implant position with FG placement, followed by PG and FH placements respectively. Therefore, a form of guided surgery is beneficial for novice clinicians.

Accuracy, Labor-Time and Patient-Reported Outcomes with Partially versus Fully Digital Workflow for Flapless Guided Dental Implants Insertion-A Randomized Clinical Trial with One-Year Follow-Up

(1) Background: Prosthetically-driven implant positioning is a prerequisite for long-term successful treatment. Transferring the planned implant position information to the clinical setting could be done using either static or dynamic guided techniques. The 3D model of the bone and surrounding structures is obtained via cone beam computed tomography (CBCT) and the patient's oral condition can be acquired conventionally and then digitalized using a desktop scanner, partially digital workflow (PDW) or digitally with the aid of an intraoral scanner (FDW). The aim of the present randomized clinical trial (RCT) was to compare the accuracy of flapless dental implants insertion in partially edentulous patients with a static surgical template obtained through PDW and FDW. Patient outcome and time spent from data collection to template manufacturing were also compared. (2) Methods: 66 partially edentulous sites (at 49 patients) were randomly assigned to a PDW or FDW for guided implant insertion. Planned and placed implants position were compared by assessing four deviation parameters: 3D error at the entry point, 3D error at the apex, angular deviation, and vertical deviation at entry point. (3) Results: A total of 111 implants were inserted. No implant loss during osseointegration or mechanical and technical complications occurred during the first-year post-implants loading. The mean error at the entry point was 0.44 mm (FDW) and 0.85 (PDW), p ≤ 0.00; at implant apex, 1.03 (FDW) and 1.48 (PDW), p ≤ 0.00; the mean angular deviation, 2.12° (FDW) and 2.48° (PDW), p = 0.03 and the mean depth deviation, 0.45 mm (FDW) and 0.68 mm (PDW), p ≤ 0.00; (4) Conclusions: Despite the statistically significant differences between the groups, and in the limits of the present study, full digital workflow as well as partially digital workflow are predictable methods for accurate prosthetically driven guided implants insertion.

In vitro evaluation of bioburden, three-dimensional stability, and accuracy of surgical templates without metallic sleeves after routinely infection control activities

BACKGROUND

Surgical templates are classified as noncritical devices, and they do not need to be sterile.

AIM

Primary aim of this study was to assess the microbiological burden present on the surgical templates without metallic sleeves after disinfection. Furthermore, to evaluate trueness after disinfection and steam sterilization at 121°C/15 min, and over a 8-week storage period. Finally, to assess their accuracy after in vitro implant placement simulation.

MATERIALS AND METHODS

Forty surgical templates were printed and divided in five groups of eight templates each. Groups A to C were disinfected with 0.5% Chlorhexidine Gluconate and 70% ethyl alcohol base solution for 15 min. Templates in the group D were steam sterilized at 121°C for 15 min, while, the templates in the group E were used as control. Implant simulation was performed in the group A. Outcome measures were determination of bioburden, trueness assessment using GOM Inspect Professional software, and accuracy evaluated thought the mean angular deviation of simulated implants.

RESULTS

Total microbic charge measured as colony forming units (CFU) for sample, was 24.40 in the control group (group E; n = 8), and <4.40 in the test group (group C; n = 8), with a reduction of 84%. Colored representation from GOM inspection showed no differences after disinfection and implant simulation, disinfection alone, and steam sterilization, compared to the control group. A very small difference in the surface and volume dimensions was reported 1 month after templates fabrication. The mean roundness tolerances of the tested templates improved of 0.96 ± 0.56° (95% CI 0.57-1.35).

CONCLUSION

Surgical templates without metallic sleeves can be safely used after disinfection, demonstrating high level of accuracy, even when the surgical procedures should be postponed within a couple of weeks. Further in vivo study are needed to confirm these preliminary results.

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

The present study aims to compare the accuracy of metal sleeve-free 3D-printed computer-assisted implant surgical guides (MSF group) (n = 10) with metal sleeve-incorporated 3D-printed computer-assisted implant surgical guides (MSI group) (n = 10). Implants of diameter 4.0 mm and 5.0 mm were placed in the left second premolars and bilateral first molars, respectively, using a fully guided system. Closed-form sleeves were used in teeth on the left and open-form sleeves on the right. The weight differences of the surgical guides before and after implant placement, and angular deviations before and after implant placement were measured. Weight differences were compared with Student's t-tests and angular deviations with Mann-Whitney tests. Cross-sectional views of the insert parts were observed with a scanning electron microscope. Preoperative and postoperative weight differences between the two groups were not statistically significant (p = 0.821). In terms of angular deviations, those along the mesiodistal direction for the left second premolars were significantly lower in the MSF group (p = 0.006). However, those along the mesiodistal direction for the bilateral molars and those along the buccolingual direction for all teeth were not significantly different (p > 0.05). 3D-printed implant surgical guides without metal sleeve inserts enable accurate implant placement without exhausting the guide holes, rendering them feasible for fully guided implant placement.

The accuracy of implant placement with computer-guided surgery in partially edentulous patients and possible influencing factors: A systematic review and meta-analysis

PURPOSE

To review the current clinical studies regarding the accuracy of implant computer-guided surgery in partially edentulous patients and investigate potential influencing factors.

STUDY SELECTION

Electronic searches on the PubMed and Cochrane Central Register of Controlled Trials databases, and subsequent manual searches were performed. Two reviewers selected the studies following our inclusion and exclusion criteria. Qualitative review and meta-analysis of the implant placement accuracy were performed to analyze potential influencing factors. Angular deviation, coronal deviation, apical deviation, and depth deviation were evaluated as the accuracy outcomes.

RESULTS

Eighteen studies were included in this systematic review, including six randomized controlled trials, nine prospective studies, and three retrospective clinical studies. A total of 1317 implants placed in 642 partially edentulous patients were reviewed. Eight studies were evaluated using meta-analysis. Fully guided surgery showed statistically higher accuracy in angular (P <0.001), coronal (P <0.001), and apical deviation (P <0.05) compared with pilot-drill guided surgery. A statistically significant difference (P <0.001) was also observed in coronal deviation between the bounded edentulous (BES) and distal extension spaces (DES). A significantly lower angular deviation (P <0.001) was found in implants placed using computer-aided design/computer-aided manufacturing (CAD/CAM) compared to the conventional surgical guides.

CONCLUSIONS

The edentulous space type, surgical guide manufacturing procedure, and guided surgery protocol can influence the accuracy of computer-guided surgery in partially edentulous patients. Higher accuracy was found when the implants were placed in BES, with CAD/CAM manufactured surgical guides, using a fully guided surgery protocol.

Immediate implant placement with or without connective tissue graft: A systematic review and meta-analysis

OBJECTIVES

To assess the effect of connective tissue graft (CTG) in terms of vertical mid-facial soft tissue change when applied at the buccal aspect following single immediate implant placement (IIP).

MATERIALS AND METHODS

Two independent reviewers conducted an electronic literature search in PubMed, Web of Science, EMBASE and Cochrane databases as well as a manual search to identify eligible clinical studies up to January 2020. Randomized controlled trials (RCTs) and non-randomized controlled studies (NRSs) comparing IIP with CTG and without CTG over a mean follow-up of at least 12 months were included for a qualitative analysis. Meta-analyses were performed on data provided by RCTs.

RESULTS

Out of 1814 records, 5 RCTs and 3 NRSs reported on 409 (IIP + CTG: 246, IIP: 163) immediately installed implants with a mean follow-up ranging from 12 to 108 months. Only 1 RCT showed low risk of bias. Meta-analysis revealed a significant difference in terms of vertical mid-facial soft tissue change between IIP + CTG and IIP pointing to 0.41 mm (95% CI [0.21; 0.61], p < .001) in favour of soft tissue grafting. This outcome was clinically relevant since the risk for ≥1 mm asymmetry in mid-facial vertical soft tissue level was 12 times (RR 12.10, 95% CI [2.57; 56.91], p = .002) lower following IIP + CTG. Soft tissue grafting also resulted in a trend towards less bleeding on probing (MD 17%, 95% CI [-35%; 1%], p = .06). Meta-analyses did not reveal significant differences in terms of pink aesthetic score, marginal bone level change and probing depth. Results were inconclusive for horizontal mid-facial soft tissue change and papilla height change. Based on GRADE guidelines, a moderate recommendation for the use of a CTG following IIP can be made.

CONCLUSION

CTG contributes to mid-facial soft tissue stability following IIP. Therefore, CTG should be considered when elevated risk for mid-facial recession is expected in the aesthetic zone (thin gingival biotype, <0.5 mm buccal bone thickness).

Effects of supporting conditions and anchor microscrew on the stabilization of the implant guide template during the drilling process: An in vitro study

STATEMENT OF PROBLEM

Implant placement errors have been reported in guided surgeries because of movement of the guide template during implant placement. With a completely limiting guide design with high restrictions, guide template stabilization is essential to minimize mobility during the drilling process.

PURPOSE

The purpose of this in vitro study was to evaluate the effects of supporting conditions and the use of an anchor microscrew on the seating and functional stabilization of a computer-aided design and computer-aided manufacturing (CAD-CAM) implant surgical guide with a completely limiting design.

MATERIAL AND METHODS

Twelve implant surgical guide templates were fabricated under different supporting conditions: tooth-mucosa, tooth-tooth, tooth-screw, and screw-screw (n=3 per group). In the tooth-screw and screw-screw groups, anchor microscrews and anchor caps were used to fix the guide templates. The seating stability of the templates was evaluated by using a micromovement assessment. The functional stability of the templates was analyzed during the drilling process by using a motion tracking method. One-way analysis of variance and the Tukey HSD post hoc test were conducted to compare the differences among the groups (α=.05).

RESULTS

The tooth-tooth, tooth-screw, and screw-screw groups exhibited similar seating stability, which was significantly more stable than that of the tooth-mucosa group (P<.001). In terms of functional stability, the tooth-mucosa group reported the highest positional deviation and motion magnitude, whereas low values were found in the tooth-screw and screw-screw groups (P<.001).

CONCLUSIONS

The use of anchor microscrews can increase the seating and functional stability of CAD-CAM guide templates during the drilling process for implant placement.

Breaking the wave of peri-implantitis

Peri-implant diseases are prevalent with a weighted mean prevalence rate of 43% across Europe and 22% across South and North America. Although the main etiologic agent is bacterial biofilm, a myriad of factors influence the initiation and progression of the disease. Unfortunately, the treatment of peri-implant diseases is at best favorable in the short term with a high rate of persistent inflammation and recurrence. Therefore, it is sensible to consider and control all potential factors that may predispose an implant to peri-implant tissue inflammation in an attempt to avoid the disease. This paper reviews recent evidence on factors that may predispose implants to peri-implantitis and measures that can be taken to prevent it.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

This comprehensive review of the 2019 restorative dental literature is offered to inform busy dentists regarding remarkable publications and noteworthy progress made in the profession. Developed by the Scientific Investigation Committee of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to 1 of 8 sections of the report: (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information likely to influence day-to-day dental treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source material when greater detail is desired. As the profession moves toward evidence-based clinical decision-making, an incredible volume of potentially valuable dental literature continues to increase. It is the intention of this review and its authors to provide assistance in negotiating the extensive dental literature published in 2019. It is our hope that readers find this work useful in the clinical management of dental patients.

Static computer-aided, partially guided, and free-handed implant placement: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To analyze the outcomes of static computer-aided implant placement (sCAIP) compared to partially guided (PGIP) and free-handed (FHIP) implant placement.

MATERIAL AND METHODS

This study was registered in PROSPERO (CRD42019131397). A comprehensive literature search was performed by two independent examiners. Only randomized controlled trials (RCTs) were selected. Treatment modalities included sCAIP, PGIP, and FHIP. Data pertaining to the outcomes of interest were extracted. Random-effects meta-analyses were feasible for a subset of outcomes.

RESULTS

From an initial list of 2,870 records, fourteen articles for a total of ten RCTs were selected. Data from 7 of these studies allowed for the conduction of three meta-analyses comparing accuracy of implant placement across modalities. Survival rate up to 12 months post-loading was high (>98%) and comparable between treatments (low-quality evidence). No tangible differences in terms of patient perception of intra- or postoperative discomfort were observed (low-quality evidence). Quantitative analyses revealed significantly lower angular (MD = 4.41°, 95% CI 3.99-4.83, p < .00001), coronal (MD = 0.65 mm, 95% CI 0.50-0.79, p < .00001), and apical (MD = 1.13 mm, 95% CI 0.92-1.34, p < .00001) deviation values for sCAIP as compared to FHIP (8 studies, 383 patients, 878 implants, high-quality evidence). A similar discrepancy, in favor of sCAIP, was observed for angular deviation only as compared to PGIP (MD = 2.11°, 95% CI 1.06-3.16, p < .00001).

CONCLUSIONS

sCAIP is associated with superior accuracy compared to PGIP and FHIP.

Utilising the nasal aperture for template stabilisation for guided surgery in the atrophic maxilla

Background

Templates aim to facilitate implant placement in the prosthetically preferred position. Mucosa-supported and bone-supported templates are commonly used in the edentulous maxilla. In the atrophic maxilla (Cawood V and VI), however, these templates can be easily displaced due to a lack of supportive tissues, even in cases where anterior sites offer sufficient bone for implant placement. To assist in positioning and stabilisation, we designed a template that utilises the nasal aperture as a fulcrum to create a forced and exclusive fit. The aim of this study was to assess the clinical usability of the developed template and the corresponding implant placement accuracy in patients with edentulous atrophic maxillae. Deviations between planned and placed implant positions were measured by aligning pre- and post-operative cone beam computed tomography scans.

Results

Twenty-four implants were placed in 11 patients. One template did not fit properly due to a slight undercut. All implants could be placed with good primary stability. The implants had high accuracy at the implant shoulder (global deviation 1.1 ± 0.5 mm, lateral deviation 0.8 ± 0.5 mm) and a mean angular deviation of 7.2 ± 3.4°.

Conclusions

The developed surgical template offers stabilised and secure template placement in the edentulous atrophic maxilla, resulting in satisfying implant placement accuracy when using a semi-guided approach.

Trial registration

Netherlands Trial Register, NL6561, registered 26 September 2017.

Accuracy of static computer-assisted implant placement in anterior and posterior sites by clinicians new to implant dentistry: in vitro comparison of fully guided, pilot-guided, and freehand protocols

Background

One of the challenges encountered by clinicians new to implant dentistry is the determination and controlling of implant location. This study compared the accuracy of fully guided (FG) and pilot-guided (PG) static computer-assisted implant placement (sCAIP) protocols against the conventional freehand (FH) protocol for placing single anterior and posterior implants by recently introduced clinicians to implant dentistry.

Material and methods

Ten clinicians new to implant dentistry inserted one anterior (central incisor) and one posterior (first molar) implants per protocol in training maxillary models. The FG protocol involved drilling and implant placement through the guide, while the PG protocol controlled the pilot drilling only. The FH implant placement was completed without the aid of any guide. A total of 30 models were used, and 60 implants were inserted. The implant vertical, horizontal neck, horizontal apex, and angle deviations from planned positions were calculated.

Results

The FG protocol provided the most accurate implant placement in relation to horizontal neck (0.47 mm–0.52 mm), horizontal apex (0.71 mm–0.74 mm), and angle deviations (2.42^o–2.61^o). The vertical deviation was not significantly different among the different protocols. The PG protocol was generally similar to the FH protocol with a horizontal neck deviation of 1.01 mm–1.14 mm, horizontal apex deviation of 1.02 mm–1.35 mm, and angle deviation of 4.65^o–7.79^o. The FG protocol showed similarity in the accuracy of the anterior and posterior implants. There was a tendency for inferior accuracy for posterior implants compared with anterior implants for the PG and FH protocols.

Conclusions

In the hands of recently introduced clinicians to implant dentistry, it appears that the accuracy of the FG protocol was superior to the other protocols and was not influenced by the position of the implants. The PG and FH protocols showed inferior accuracy for posterior implants compared with anterior implants.

Role of three-dimensional printing in periodontal regeneration and repair: Literature review

Three-dimensional (3D) printing is the process of building 3D objects by additive manufacturing approach. It is being used in endodontics, periodontology, maxillofacial surgery, prosthodontics, orthodontics, and restorative dentistry, but our review article is focused on periodontal application. A detailed literature search was done on PubMed/Medline and Google Scholar using various key terms. A total of 45 articles were included in this study. Most of the studies were in vitro, preclinical, case reports, retrospective, and prospective studies. Few clinical trials have also been done. Periodontal applications included education models, scaffolds, socket preservation, and sinus and bone augmentation and guided implant placement. It showed better alveolar ridge preservation, better regenerative capabilities, greater reduction in pocket depth and bony fill, ease of implant placement in complex cases with greater precision and reduced time with improved outcome and an important tool for education and training using simulated models.