Assessment of a novel electrochemically deposited smart bioactive trabecular coating (SBTC®): a randomized controlled clinical trial.

OBJECTIVES: A randomized controlled clinical trial of dental implants was conducted to compare the clinical properties of a novel electrochemically deposited calcium phosphate coating to those of a common marketed surface treatment. MATERIAL AND METHODS: Forty implants of the same brand and type were placed in 20 fully edentulous participants requiring mandibular implantation. The two study groups were defined by the surface treatment of the implants. 20 implants in the control group were coated via a commercial electrochemical surface treatment that forms a mixture of brushite and hydroxyapatite, while the remaining 20 in the test group were coated with a novel electrochemical Smart Bioactive Trabecular Coating (SBTC®). A split-mouth design was employed, with each participants receiving one control implant in one mandibular side and a test implant in the other. To mitigate potential operator-handedness bias, control and test implants were randomly assigned to mandibular sides. All cases underwent digital planning, implant placement with a static surgical guide, and participants received locator-anchored full-arch dentures. The primary outcome was implant stability (measured using Osstell ISQ) assessed at insertion, loading, and then 3 months, 9 months, and 2 years post-insertion. The secondary outcome was bone level change (in millimeters) over the 2-year observation period. Oral health-related quality of life (OHRQL) was monitored using the OHIP-14 questionnaire. Complications and adverse events were recorded. RESULTS: Successful osseointegration and implant stability were achieved in all cases, allowing loading. ISQ values steadily increased throughout the observation period. While no significant differences were observed between the SBTC® and control coatings, the test group exhibited a higher ISQ gain. Bone resorption was somewhat lower in the SBTC® but not significantly so. Patients' OHRQL significantly improved after denture delivery and remained stable throughout the follow-up. No complications or adverse events were observed. CONCLUSIONS: Based on the study results, we conclude that the new surface treatment is a safe alternative to the widely used control surface, demonstrating similar osseointegrative properties and time-dependent bone level changes. Further research may explore the broader implications of these findings. TRIAL REGISTRATION: The study is registered on clinicaltrials.gov under the identifier ID: NCT06034171.

Evaluation and assessment of the survival of tooth implant supported prosthesis in tooth and implant supported rehabilitation cases with metal frameworks.

INTRODUCTION: Over the years, implant therapy has been a commonly used treatment option for individuals who are partially or totally edentulous, with a long-term success rate of over 90%. With significant advancements in biomaterials and technology, implant dentistry can now conduct prosthetic rehabilitations in the majority of patients catering to all types of needs. However, in order to meet the demands of a patient base that is always growing, new trends in implantology are emerging in recent years that are focused on minimally invasive surgery and financial sustainability. In certain clinical scenarios, connecting teeth and implants to support fixed partial prosthesis (FPPs) may be a predictable and workable course of treatment. MATERIALS AND METHODS: 22 patients were selected for this study who had tooth and implant supported prosthesis placed as a final restoration. Out of these 22 patients; 12 were male and 10 were female patients. Implants were placed following proper protocol and if grafting procedures were required they were carried out. A second stage surgical procedure was carried out and delayed loading protocols were followed. The statistical analysis was done using the IBM SPSS 24.0, Chicago, USA. The survival of the implants and teeth were measured by the Kaplan Meier survival scale. Bone loss was assessed at baseline(upon loading), 12 months and 24 months. RESULTS: The implant survival rate was measured at 6 months, 12 months, 18 months and 24 months. At 24 months, one implant showed failure, so the survival rate of the implants were 95.4%. Bone loss of 1 mm was seen around one implant at 12 months. Bone loss of 1 and 2 mm was present around two implants and one implant respectively at 24 months. CONCLUSION: From the results of this study, we can conclude that tooth implant supported prosthesis show very good survival when used in rehabilitation cases.

Classified diagnosis and treatment scheme of oral cosmetic restoration based on aesthetic analysis (part â ): basic concept, decision tree and clinical pathway.

At present, the commonly used clinical protocols of oral comestic restoration are mostly based on the aesthetic indicators proposed by Western developed countries (referred to as Western aesthetics). Mechanically copying the Western aesthetic scheme, ignoring the difference between it and the Chinese oral aesthetic indicators (referred to as Chinese aesthetics), is unable to effectively support personalized cosmetic restoration diagnosis and treatment. In addition, new technologies and new solutions for cosmetic restoration, which are developing rapidly in recent years, are emerging one after another, but many popular concepts are confusing and lack of proper hierarchical diagnosis and treatment norms, and there is indeed an urgent need for discussion and clarity. From the perspective of serving clinical application, this paper discusses the deficiencies of the Chinese translation of the word "aesthetics", the diffe-rence and connection between aesthetics and cosmetology, and the relationship between cosmetic restoration and fixed restoration. It also discusses the difference between anterior teeth, esthetic zone and exposed zone, the diagnostic and therapeutic value of oral aesthetic analysis, as well as the application methods of desensitization, suggestion, and other therapies in difficult oral cosmetic restoration cases. We further introduce the decision tree and the clinical pathway for restoration and reconstruction of teeth in exposed zone guided by aesthetic analysis, and introduce the clinical process of aesthetic analysis and evaluation, the clinical triclassification of oral cosmetic restoration, and the corresponding clinical classification diagnosis and treatment points.

Assessment of the intrasinusidal volume before and after maxillary sinus augmentation using mri - a pilot study of eight patients.

PURPOSE: The purpose of this study was to evaluate the suitability, accuracy, and reliability of a non-invasive 3-Tesla magnetic resonance imaging technique (3 T-MRI) for the visualization of maxillary sinus grafts in comparison to conventional, X-ray-based, established standard imaging techniques. METHODS: A total of eight patients with alveolar bone atrophy who required surgical sinus floor augmentation in the course of dental implantation were included in this pilot study. Alongside pre-operative cone-beam computed tomography (CBCT), 3 T-MRI was performed before and 6 months after sinus floor augmentation. Two investigators measured the maxillary sinus volume preoperatively and after bone augmentation. RESULTS: In all cases, MRI demonstrated accurately the volumes of the maxillary sinus grafts. Following surgery, the bony structures suitable for an implant placement increased at an average of 4.89 cm3, corresponding with the decrease of the intrasinusidal volumes. In general, interexaminer discrepancies were low and without statistical significance. CONCLUSION: In this preliminary study, we could demonstrate the feasibility of MRI bone volume measurement as a radiation-free alternative with comparable accuracy to CT/CBCT before procedures like sinus floor augmentation. Nevertheless, costs and artifacts, also present in MRI, have to be taken into account. Larger studies will be necessary to justify the practicability of MRI bone volume evaluation.

Ridge augmentation planning, wound healing evaluation, and peri-implant tissue phenotype assessment with ultrasonography: A case report.

BACKGROUND: Ridge regeneration for implant therapy requires comprehensive site evaluation and wound healing monitoring. This case report aimed to demonstrate ultrasound (US) can image soft and hard tissues for surgical planning and assess longitudinal outcomes. METHODS AND RESULTS: US was used in a patient planned for ridge augmentation to evaluate soft tissue thickness, location of muscle attachment, and hard tissue defect features presurgically. US were obtained at 1, 2.5, and 5 months afterward to assess tissue healing. Preoperatively, US showed ∼2.5 mm and ∼0.8 mm soft tissue thickness on the facial and lingual sides, respectively. The crestal bone width was ∼2 mm, with severe facial bone deficiency and high muscle attachment. US showed wound approximation and ridge width gain to 4.5 and 4.0 mm at 1 and 5 months, respectively. US tissue perfusion increased to ∼two-fold and ∼4-fold at 1 and 2.5 months and reduced below the baseline at 5 months. An implant with simultaneous bone augmentation was performed accordingly. Tissue phenotype around the implant was measured on US images at 1-year visit. CONCLUSIONS: This case report demonstrated that US parameters could be valuable for planning and wound healing outcome assessment of ridge augmentation in clinical as well as research settings. KEY POINTS: Why is this case new information? Novel high-resolution, chairside ultrasound was proposed to facilitate treatment planning and wound healing outcome assessment of ridge augmentation in clinical as well as research settings. What are the keys to successful use of this technology? Proper training in imaging acquisition and interpretation Adhere to high-level disinfection protocol Patient education and explanation What are the primary limitations to success in using this technology? Investment in this technology Learning curve in imaging acquisition and reading Insurance reimbursement strategy.

Radiographic alveolar bone assessment in correlation with primary implant stability: A systematic review and meta-analysis.

INTRODUCTION: The radiographic examination of alveolar bone using 3D radiographic examination is essential in dental implant treatment planning. Our study aimed to systematically review and quantitatively analyze the correlation between alveolar bone parameters, specifically bone density and cortical bone thickness, assessed using cone beam computed tomography (CBCT) and/or multidetector computed tomography (MDCT); and primary implant stability (PIS) determined using implant stability quotient (ISQ), Periotest® value (PTV), and insertion torque value (ITV). METHODS: This review was registered in the PROSPERO database (registration number CRD42022307245). An electronic literature search was conducted on the PubMed, SCOPUS, and Web of Science databases for papers published until February 2022. The Quality Assessment in Prognostic Studies (QUIPS) tool was used to assess risk of bias. Meta-analyses were conducted to calculate the estimated average correlation coefficient based on a multilevel random-effects model, followed by subgroup analysis. RESULTS: Twenty-six studies were included in this review, consisting of 17 prospective cohort studies, eight retrospective cohort studies, and one nonrandomized controlled trial. A total of 3109 implants placed in 1171 subjects were analyzed. Twenty-three studies were evaluated using meta-analysis. The alveolar bone condition was significantly correlated with ISQ (r = 0.60; p < .001), IT (r = 0.52; p < .001), and PTV (r = -0.42; p < .05). CONCLUSION: Alveolar bone condition is significantly associated with PIS. Low bone density and thin cortical bone can lead to low PIS; therefore, modification of treatment planning and surgical procedures might be needed to avoid poor osseointegration.

Effectiveness, Morbidity, and Costs of Transcrestal and Lateral Sinus Floor Elevation at Sites with Different Residual Bone Heights: A Re-Analysis of Data from a Parallel-Arm Randomized Trial.

PURPOSE: To comparatively evaluate transcrestal sinus floor elevation (tSFE) and lateral sinus floor elevation (lSFE) at sites with different residual bone heights (RBHs). MATERIALS AND METHODS: A re-analysis of data from a parallel-arm, randomized trial comparatively evaluating tSFE and lSFE was performed. Within each RBH interval (< 4 mm or ≥ 4 mm), tSFE and lSFE groups were compared for chair time, surgery-related costs, morbidity, and radiographic parameters (including the proportion of the implant surface in direct contact with the radiopaque area [totCON%]). RESULTS: The intention-to-treat (ITT) population consisted of 29 and 28 patients in the tSFE and lSFE groups, respectively. Irrespective of RBH, both tSFE and lSFE lead to a median totCON% of 100%. At sites with RBH < 4 mm, pain severity was significantly higher at days 0 and 1 in the tSFE group, with no intergroup difference in the dose of analgesics. LSFE was associated with a significantly higher frequency of bruising and greater cost. At sites with RBH ≥ 4 mm, a significantly lower frequency of postoperative signs/symptoms, less chair time, and lower costs were observed in the tSFE group. CONCLUSIONS: The selection of tSFE or lSFE within the investigated RBH intervals seems to be supported by differences in chair time, costs, and morbidity between the two techniques. At sites with RBH < 4 mm, clinicians preferring tSFE should encourage the administration of analgesics according to a predefined plan in the early postoperative phase. At sites with RBH ≥ 4 mm, tSFE should be preferred to lSFE due to reduced chair time, costs, and morbidity.

Comparative Assessment of Three Different Alveolar Ridge Dimension Measurement Methods before Implant Placement: An In Vivo Study.

AIM: The purpose of this study was to compare the three various techniques for measuring the alveolar ridge's dimensions prior to implant insertion. MATERIALS AND METHODS: For this study, a total of 36 participants were chosen. To prepare a surgical stent, a study model was created from an alginate impression. A first point (reference point) was marked on the crest of the ridge in relation to the adjacent teeth. Then, one point (point 1) and another point (point 2) were marked at distances of 3 and 6 mm, respectively, from the reference point. Based on the procedure for measuring the size of the alveolar ridge, the study was divided into the following groups. Group I: Cone-beam computed tomography (CBCT) measurement method; Group II: Ridge mapping measurement method; Group III: Direct caliper measurements method. Descriptive statistics were used to estimate the mean and standard deviation (SD). The Student's unpaired t-test was utilized for the statistical analysis. The 5% level of significance was used. RESULTS: There was no significant difference found between CBCT with ridge mapping and direct caliper measurements. However, on comparison of ridge mapping and direct caliper measurements technique, at point 1, the ridge mapping was 3.88 ± 0.12 and the direct caliper measurement was 3.62 ± 0.08. At point 2, the ridge mapping was 6.58 ± 0.06 and the direct caliper measurement was 6.32 ± 0.04. There was a statistically significant difference found between these two measurement methods. CONCLUSION: Within the limitation, the current study came to the conclusion that when CBCT and ridge mapping measurements were individually compared with the gold standard-the surgical open method, CBCT-demonstrated to be a highly specific and sensitive method for detecting the residual alveolar ridge width in the treatment planning of dental implants. CLINICAL SIGNIFICANCE: Evaluation of alveolar bone is necessary during treatment planning for dental implant placement. Using simply panoramic and/or periapical radiographs to evaluate the bone may not be sufficient because it only provides two-dimensional information regarding the implant locations. Therefore, for better implant placement, three-dimensional information of the implant site, such as CBCT and ridge mapping technique, should be assessed.

Timing of soft tissue augmentation around implants: A clinical review and decision tree.

PURPOSE: The goal of soft tissue augmentation is to improve the volume around implants and thus achieve better aesthetic and functional properties. The present review aims to make recommendations and guide clinicians in performing soft tissue augmentation procedures, focusing on the importance of timing. OVERVIEW: Soft tissue augmentation can be performed at different time points: before or after implant placement, at implant placement (immediate/delayed), at healing abutment connection or after final restoration. Before/after implant placement or at healing abutment connection are considered the gold standard time points at which to perform soft tissue augmentation due to the possibility of achieving complete coverage of the soft tissue graft or its substitute through simple flap elevation and the easy handling of tissue. On the other hand, performing soft tissue augmentation at implant placement or after crown delivery seems to be less predictable due to the different healing approaches and the unexpected shrinkage that occurs. CONCLUSION: Timing needs to be considered when performing soft tissue augmentation, taking into account the advantages and disadvantages related to operator experience, implant position and patient expectations. Employing a reliable approach at the appropriate time of intervention could limit complications.

Restoratively driven planning for implants in the posterior maxilla - Part 1: alveolar bone healing, bone assessment and clinical classifications.

Sinus augmentation in conjunction with implant placement is widely considered to be a predictable and successful treatment option for the edentulous posterior maxilla. However, the anatomical changes of the posterior maxilla following tooth extraction (namely alveolar atrophy and pneumatisation of the maxillary sinus) creates unique challenges for implant and prosthodontic rehabilitation. A large volume of literature has been published regarding the surgical indications and treatment planning for implants in the posterior maxilla. In comparison, there is a relative paucity of literature regarding the prosthodontic challenges associated with implants placed in augmented maxillary sinuses. This article describes the scientific background of native and grafted alveolar bone healing in relation to implant rehabilitation. Furthermore, clinical classifications available to assist implant treatment planning are described.

Risk assessment of mandibular incisive canal perforation during dental implant surgery in the anterior edentulous mandible: a virtual implant placement study using cone beam computed tomography.

OBJECTIVE: The aim of this study was to evaluate the risk of mandibular incisive canal (MIC) perforation caused by implants placed on cone beam computed tomography (CBCT) images in the edentulous mandibular anterior region. STUDY DESIGN: A total of 1200 dental implants were virtually inserted on 150 eligible CBCT scans. The relationship of different implant sizes with the incidence of MIC perforation and the relationship between crest height and perforation were evaluated. RESULTS: A total of 1200 virtual implant applications were performed on 150 patients. In 87% of cases, MIC was identified. Perforation in 12 and 14 mm implants was significantly higher than in 8- and 10-mm implants (P < .05). Perforation was found to be statistically significantly higher in crest heights that were ≤20 mm than in crest heights >20 mm (P < .05). CONCLUSIONS: Our results showed high perforation rates in the 12- and 14-mm implants and crests heights that were ≤20 mm during implant surgery in the mandibular anterior edentulous region. Perforation of the MIC should be considered a complication of implant surgery in the mandibular anterior region; therefore, CBCT images should be evaluated before implant placement.

Assessment of the alveolar bone loss in fresh socket implant procedures with immediate implant loading via temporary preformed anatomical healing caps: Comparison of two different lengths of the implant collar.

PURPOSES: The aim of the present clinical and radiologic retrospective study was to evaluate alveolar bone remodeling, in terms of alveolar width and peri­implant bone level, two years after immediate implant positioning (with two different collar lengths, 0.8 mm and 2.0 mm) and loading of preformed healing cap. The Null hypothesis, H0 is: there was no difference between the two groups of implants. METHODS: Patients suffering from single-tooth edentulous areas in premolar, cuspid, and incisive areas were treated with fresh-socket implants and immediate preformed anatomical healing caps. Each final crown restoration was fabricated 3 months later. Primary outcomes (related to loss of the alveolar width and peri­implant bone level) and secondary outcomes (testing adverse events, and measuring implant/prosthesis survival) were acquired and analyzed. RESULTS: A two-year retrospective analysis was conducted on 31 patients (19 female and 12 male), who underwent dental implant placement with implants having two different lengths of the collar: group A, 0.8 mm, and group B, 2.0 mm. As for the width of the alveolar crest, there was a negligible loss (less than half a millimeter) reported for both the groups, anyway reaching a statistical significance. Preoperative alveolar widths (9.50±0.67 mm and 9.45±0.90 mm, respectively for groups A and B) were different from the two-year alveolar widths (9.20±0.74 mm and 8.93±0.99 mm, respectively for groups A and B) with p-values ≤ 0.0049. When the marginal bone loss was assessed, significant differences were registered between the two procedure groups (-1.42±0.34 mm for group A and -0.11±0.15 mm for group B with a p-value < 0.0001). CONCLUSIONS: The proper design of a healing abutment was very important to preserve the emergence profile immediately after extraction and implant placement. The length of the implant collar used with an immediate healing abutment appeared to affect the preservation of the alveolar crest with predictable final results.

Bone assessment around the delayed dental implant with and without preformed anatomical caps: A 1-year retrospective case-control study.

PURPOSES: To investigate the amount of first-year peri­implant bone loss and the development of the papillae when delayed dental implants loaded with anatomic cover screw and those underwent conventional healing protocol were compared. METHODS: Edentulous healed sites had undergone delayed implants placement. In the anatomical cap group, patients were treated with a guided tissue healing, tooth-like cross-linkable acrylic resin caps had been immediately screwed on dental implants. The marginal loss of the alveolar bone height 1 year after surgery and Jemt's papillae index were obtained. Non-parametric statistics were performed with a level of significance of 1% RESULTS: Forty patients were included in the present retrospective analysis. After a follow-up of 1 year, none of the 40 included implants showed a failure. The Jemt's papilla index was 1.76±0.44 and 1.34±0.50 respectively for guided tissue healing and conventional healing group, without any significant difference. Within the first year of survey a bone loss of -1.27±0.26 mm for conventional healing treatment showed a statistically significant difference (p-value<0.0001) when it was compared to the negligible of the other group (-0.06±0.31 mm). CONCLUSIONS: A guided healing procedure with preformed caps seemed to give better outcomes regarding marginal bone loss and papilla index than those of conventional abutments.

Accuracy assessment of dynamic navigation during implant placement: A systematic review and meta-analysis of clinical studies in the last 10 years.

OBJECTIVES: To evaluate the accuracy of dynamic computer-aided implant surgery (dCAIS) and compare it with static computer-aided implant surgery (sCAIS) and freehand implant placement (FH) in partially or fully edentulous patients. DATA: Studies that analyzed the accuracy of dynamic computer-assisted implant surgery in partially or fully edentulous patients. SOURCES: This meta-analysis included studies published in English and Mandarin Chinese from January 2013 to February 2023 from MEDLINE/PubMed, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), and CNKI (China National Knowledge Infrastructure). STUDY SELECTION: Only clinical studies were included. Accuracy was the primary outcome. Seventeen studies met the inclusion criteria. A total of 2,025 implants were analyzed. Meta-regression was conducted to compare the six different navigation systems. GRADE (Grading of Recommendations Assessment, Development, and Evaluation) assessment was adopted as a collective grading of the evidence. CONCLUSIONS: Dynamic navigation is a clinically reliable method for implant placement. Significantly lower angular deviation was observed for dCAIS compared to both sCAIS and FH, while significantly lower global platform and apex deviations were displayed between dCAIS and FH. Overall, dynamic navigation allowed for higher accuracy compared to both sCAIS and FH in a clinical setting; however, additional large sample RCT studies should be conducted, and patient-reported outcome measures (PROMs) reported. CLINICAL SIGNIFICANCE: This systematic review analyzed the accuracy of dynamic computer-assisted implant surgery in partially or fully edentulous patients compared with static navigation. The results demonstrated that dynamic navigation could decrease implant placement angular deviations.

Accuracy and safety of a haptic operated and machine vision controlled collaborative robot for dental implant placement: A translational study.

OBJECTIVES: Multiple generations of medical robots have revolutionized surgery. Their application to dental implants is still in its infancy. Co-operating robots (cobots) have great potential to improve the accuracy of implant placement, overcoming the limitations of static and dynamic navigation. This study reports the accuracy of robot-assisted dental implant placement in a preclinical model and further applies the robotic system in a clinical case series. MATERIALS AND METHODS: In model analyses, the use of a lock-on structure at robot arm-handpiece was tested in resin arch models. In a clinical case series, patients with single missing teeth or edentulous arch were included. Robot-assisted implant placement was performed. Surgery time was recorded. Implant platform deviation, apex deviation, and angular deviation were measured. Factors influencing implant accuracy were analyzed. RESULTS: The in vitro results showed that with a lock-on structure, the mean (SD) of platform deviation, apex deviation, and angular deviation were 0.37 (0.14) mm, 0.44 (0.17) mm, and 0.75 (0.29)°, respectively. Twenty-one patients (28 implants) were included in the clinical case series, 2 with arches and 19 with single missing teeth. The median surgery time for single missing teeth was 23 (IQ range 20-25) min. The surgery time for the two edentulous arches was 47 and 70 min. The mean (SD) of platform deviation, apex deviation, and angular deviation was 0.54 (0.17) mm, 0.54 (0.11) mm, and 0.79 (0.22)° for single missing teeth and for 0.53 (0.17) mm, 0.58 (0.17) mm, and 0.77 (0.26)° for an edentulous arch. Implants placed in the mandible had significantly larger apex deviation than those in the maxilla. CONCLUSION: Cobot-assisted dental implant placement showed excellent positional accuracy and safety in both the in vitro study and the clinical case series. More technological development and clinical research are needed to support the introduction of robotic surgery in oral implantology. Trial registered in ChiCTR2100050885.

Accuracy assessment of implant placement with versus without a CAD/CAM surgical guide by novices versus specialists via the digital registration method: an in vitro randomized crossover study.

BACKGROUND: Many studies demonstrated that surgical guides might reduce discrepancies compared with freehand implant placement. This randomized crossover study aimed to assess the effects of approaches, practitioners' experience and learning sequences on the accuracy of single tooth implantation via digital registration method. No similar study was found. METHODS: This in vitro randomized crossover study enrolled 60 novice students (Group S) and 10 experienced instructors (Group I). Sixty students were randomly and evenly assigned to two groups (Group SA and SB). In Group SA, 30 students first performed single molar implant on a simulation model freehand (Group SAFH), and then with a CAD/CAM surgical guide (Group SASG). In Group SB, another 30 students first performed guided (Group SBSG) and then freehand (Group SBFH). Ten instructors were also divided into Group IAFH/IASG (n = 5) and IBSG/IBFH (n = 5) following the same rules. The accuracy of implant placement was assessed by the coronal and apical distance (mm) and angular (°) deviations using the digital registration method. T tests and nonparametric tests were used to compare the results among different groups of approaches, experience and sequences. RESULTS: For students, the coronal and apical distance and the angular deviations were significantly lower in surgical guide group than freehand group in total and in learning freehand first subgroup, but for learning surgical guide first subgroup the apical distance deviation showed no significant difference between two approaches. For students, the angular deviation of freehand group was significantly lower in learning surgical guide first group than learning freehand first group. For instructors, the coronal and apical distance and angular deviations showed no significant difference between two approaches and two sequences. For freehand approach, the coronal and apical distance and the angular deviations were significantly higher in student group than instructor group, while not significantly different between two groups for surgical guide approach. CONCLUSIONS: For novices, using a surgical guide for the first implant placement may reduce the potential deviations compared with freehand surgery, and may reach a comparable accuracy with that of specialists. For simple single molar implantation, the surgical guide may not be significantly helpful for experienced specialists.

Comparative assessment of the positional accuracy of dental implants inserted using computerised stackable surgical guides made using selective laser melting and digital light processing technologies for patients with maxillary terminal dentition.

PURPOSE: To make a comparative estimation of the positional accuracy of dental implants inserted using selective laser melting and computerised stackable surgical guides produced through digital light processing for patients with maxillary terminal dentition. MATERIALS AND METHODS: Twenty-four dental implants were inserted in partially edentulous patients who were treated for tooth loss and required fixed prosthodontic rehabilitation. Virtually designed prosthetically driven fixation bases with stackable surgical osteotomy guides were used for bone reduction after tooth extraction and osteotomy preparation, respectively. The inserted implants were divided into two equal groups according to the type of surgical guide used, either cobalt-chromium guides fabricated through selective laser melting or resin guides produced by digital light processing. The final actual implant position was compared to the preoperative planned position and the coronal and apical deviations were calculated in millimetres, and angular deviation measurements in degrees. RESULTS: A t test was used for comparison (P < 0.05). The mean coronal, apical and angular deviation for the implants positioned using a stackable guide made by digital light processing were greater than those for implants positioned using cobalt-chromium guides fabricated through selective laser melting. Highly significant differences were found between both groups for all the measurements. CONCLUSIONS: Within the limitations of this study, cobalt-chromium stackable surgical guides produced by selective laser melting are more accurate than resin guides produced through digital light processing.

Volume assessment of the external contour around immediate implant with or without immediate tooth-like crown provisionalization: A digital intraoral scans study.

PURPOSES: To examine differences between immediate and delayed dental implant loading in maxillary aesthetic areas. METHODS: In this retrospective controlled analysis, 43 subjects who underwent immediate placement of the dental implant in a post-extraction socket were ranked into either immediate (24 implants loaded with non-occlusal tooth-like profile provisional prostheses fabricated by virtual diagnostic impressions and an in-office dental milling machine) or delayed group (19 implants loaded with conventional cover screws and secondary intention healing). Intraoperatively and then four months later, scans of the external layers were acquired with an optical scanner. The width of the alveolar crest and Jemt papilla index were acquired. Non-parametric tests were applied with a level of significance set at p < 0.01. RESULTS: In both groups, the volumes and areas showed significant reductions from the baseline to the 4-month survey. Reductions in volume appeared to be statistically different between the two groups (-39±31 mm3 for the immediate and 89 ± 30 mm3 for the delayed group). The final Jemt papilla index appeared significantly different between the immediate (mesial, 2.5 and, distal, 3) and delayed groups (2 for both aspects). CONCLUSIONS: Immediate provisionalization significantly reduced volume loss and area shrinkage at the external layer when data were compared to a delayed rehabilitation strategy.

Three-dimensional volumetric assessment of hard tissue alterations following horizontal guided bone regeneration using a split-thickness flap design: A case series.

OBJECTIVES: To analyze morphological, volumetric, and linear hard tissue changes following horizontal ridge augmentation using a three-dimensional radiographic method. METHODS: As part of a larger ongoing prospective study, 10 lower lateral surgical sites were selected for evaluation. Horizontal ridge deficiencies were treated with guided bone regeneration (GBR) using a split-thickness flap design and a resorbable collagen barrier membrane. Following the segmentation of baseline and 6-month follow-up cone-beam computed tomography scans, volumetric, linear, and morphological hard tissue changes and the efficacy of the augmentation were assessed (expressed by the volume-to-surface ratio). RESULTS: Volumetric hard tissue gain averaged 605.32 ± 380.68 mm3. An average of 238.48 ± 127.82 mm3 hard tissue loss was also detected at the lingual aspect of the surgical area. Horizontal hard tissue gain averaged 3.00 ± 1.45 mm. Midcrestal vertical hard tissue loss averaged 1.18 ± 0.81 mm. The volume-to-surface ratio averaged 1.19 ± 0.52 mm3/mm2. The three-dimensional analysis showed slight lingual or crestal hard tissue resorption in all cases. In certain instances, the greatest extent of hard tissue gain was observed 2-3 mm apical to the initial level of the marginal crest. CONCLUSIONS: With the applied method, previously unreported aspects of hard tissue changes following horizontal GBR could be examined. Midcrestal bone resorption was demonstrated, most likely caused by increased osteoclast activity following the elevation of the periosteum. The volume-to-surface ratio expressed the efficacy of the procedure independent of the size of the surgical area.