The influence of radiographic marker registration versus a markerless trace registration method on the implant placement accuracy achieved by dynamic computer-assisted implant surgery. An in-vitro study.

OBJECTIVES: This study aimed to compare the effect the radiographic marker registration (RMR) and markerless tracing registration (MTR) on implant placement accuracy using a dynamic computer-assisted implant surgery system (dCAIS). Additionally, this study aimed to assess the surgical time and whether the implant location influences the accuracy of the two registration methods. METHODS: 136 dental implants were randomly allocated to the RMR or MTR group and were placed with a dCAIS in resin models. Preoperative and postoperative Cone Beam Computer Tomograms (CBCT) were overlaid and implant placement accuracy was assessed. Descriptive and multivariate analysis of the data was performed. RESULTS: Significant differences (P < 0.001) were found for all accuracy variables except angular deviation (RMR:4.30° (SD:4.37°); MTR:3.89° (SD:3.32°)). The RMR had a mean 3D platform deviation of 1.53 mm (SD:0.98 mm) and mean apex 3D deviation of 1.63 mm (SD:1.05 mm) while the MTR had lower values (0.83 mm (SD:0.67 mm) and 1.07 mm (SD:0.86 mm), respectively). In the MTR group, implant placement in the anterior mandible was more accurate (p < 0.05). Additionally, MTR did not significantly increase the surgical time compared with RMR (P = 0.489). CONCLUSIONS: MTR seems to increase the accuracy of implant placement using dCAIS in comparison with the RMR method, without increasing the surgical time. The operated area seems to be relevant and might influence the implant deviations. CLINICAL SIGNIFICANCE: Considering the limitations of this in-vitro study, MTR seems to provide a higher accuracy in implant placement using dCAIS without increasing the surgical time. Furthermore, this method does not require radiographic markers and allows re-registration during surgery.

Peri-implantitis in patients without regular supportive therapy: Prevalence and risk indicators.

OBJECTIVES: To determine the prevalence of peri-implant diseases in patients treated in a university setting without a regular peri-implant supportive therapy schedule, and to identify the risk indicators associated with peri-implantitis. MATERIAL AND METHODS: A retrospective cohort study was made of patients with dental implants with at least 12 months of functional loading who did not receive regular peri-implant supportive therapy. Patient- and implant-related variables were retrieved, and clinical and radiological examinations were performed. Descriptive and bivariate analyses and multilevel logistic regression analyses were performed to identify factors associated with peri-implantitis. RESULTS: A total of 213 implants in 88 patients were analyzed. The patient-level prevalence of peri-implantitis and peri-implant mucositis was 26.1% (95%CI: 16.7%-35.5%) and 44.3% (95%CI: 34.0%-54.6%), respectively. Peri-implant diseases were significantly more frequent when the width of the keratinized mucosa was < 2 mm (OR = 5.26; 95%CI: 1.24-22.26; p = 0.024), and when there was 12 month post-loading bone loss (OR = 2.96; 95%CI: 1.35-6.52; p = 0.007). CONCLUSIONS: Peri-implantitis is a common finding in patients without regular peri-implant supportive therapy (prevalence 16.7-35.5%). A thin peri-implant keratinized mucosa (< 2 mm) and a higher degree of bone remodeling after loading seem to be the main risk factors for peri-implantitis in this patient profile. CLINICAL RELEVANCE: Patients who do not engage in supportive peri-implant maintenance have a higher risk of peri-implantitis. A thin keratinized mucosa and bone loss during the first year of loading are predisposing factors for peri-implantitis.

Validity and reliability of the Spanish version of the consultation and relational empathy measure in dental students (Sp-Dent-CARE): A cross-sectional study.

INTRODUCTION: An evaluation was made of the psychometric properties of a Spanish version of the Consultation and Relational Empathy Measure (CARE) to assess relational empathy in undergraduate dental students. In addition, the influence of demographic, socio-economic and consultation-related factors upon the degree of perceived empathy and overall satisfaction was studied. MATERIALS AND METHODS: A cross-sectional study was carried out in patients seen in the Oral Surgery Unit by fourth year dental students. Dentists, specialized translators and psychologists developed the translation of the questionnaire. After a pilot test, a convenience sample of patients was included. Construct validity was tested by factor analysis using principal component analysis with varimax rotation and Kaiser standardization, and internal consistency was assessed by Cronbach's α. RESULTS: Two pilot tests were carried out with a panel of experts until the final version of the questionnaire was established. In the validation stage, 191 patients participated (92 men and 99 women), with a mean age of 52.5 ± 17 years. The mean score of the CARE measure was 47.2 ± 4.4, and 57.6% of the patients (n = 110) reported the maximum score on the questionnaire. The final version showed a 1-factor solution explaining 68.6% of the total variance, with excellent final internal consistency (α = 93.4%). CONCLUSION: The Spanish version of the CARE measure affords high reliability and validity in assessing relational empathy in dental students. Perceived empathy is related to overall satisfaction. Patient demographics and the number of visits do not influence perceived empathy.

In Vitro Characterization of an Anodized Surface of a Dental Implant Collar and Dental Abutment on Peri-Implant Cellular Response.

The purpose of this paper was to determine the effect of anodization on the in vitro proliferation and adhesion of immortalized human keratinocytes (HaCats) and mouse bone marrow-derived mesenchymal stem cells (BM-MSCs) in Titanium Grade 23 (Ti6Al4V ELI) discs and to describe the surface topography, roughness, and composition of dental implants (body and collar) and abutments submitted to an area-specific anodization process. HaCat cells and BM-MSCs were seeded onto discs with three different surface treatments: machined, area-specific anodization for abutments, and area-specific anodization for implant collars. Cell proliferation was assessed using a resazurin-based fluorescent dye on days 1, 3, and 7, while cell adhesion was examined using scanning electron microscopy (SEM). Surface topography, roughness, and composition were evaluated for six implant bodies with an anodized rough surface, six anodized implant smooth collars, and six anodized prosthetic abutments. Both HaCats and BM-MSCs showed increased viability over time (p < 0.001) with no statistically significant differences among the different surfaces (p = 0.447 HaCats and p = 0.631 BM-MSCs). SEM analysis revealed an enhanced presence and adhesion of HaCat cells on the anodized surface for the implant collars and an increased adhesion of BM-MSCs on both the anodized and machined surface abutments. The topography characteristics of the treated implants and abutments varied depending on the specific implant region. Chemical analysis confirmed the presence of oxygen, calcium, phosphorus, and sodium on the anodized surfaces. The area-specific anodization process can be utilized to create variable topography, increase the specific surface area, and introduce oxygen, calcium, phosphorus, and sodium to dental implants and abutments. While BM-MSCs and HaCat cells showed similar adhesion and proliferation on anodized and machined surfaces, a positive interaction between anodized Ti6Al4V ELI surfaces and these two cell lines present in the peri-implant mucosa was observed. Due to the limitations of the present study, further research is necessary to confirm these findings.

Factors Affecting Implant Surface Roughness and Platform Alterations After Implantoplasty: An In Vitro Study Simulating Different Clinical Scenarios.

Purpose: To determine which clinical factors might affect the postimplantoplasty presence of residual threads, platform alterations, and level of surface roughness. Materials and Methods: A total of 60 implants were placed in 20 resin models (10 edentulous maxillary models and 10 partially dentate mandibular models), and 5-mm peri-implant bone defects were created. These models were then placed in simulation mannequins. A single researcher performed the implantoplasties, which were divided into the following groups: favorable situation (FS; maxillary incisors without adjacent teeth), unfavorable situation (US; mandibular molars with adjacent teeth), crown (C; mandibular premolars with a prosthetic crown and adjacent teeth), and noncrown (NC; mandibular premolars with adjacent teeth and without a prosthetic crown). The presence of residual threads, gaps in the implant-abutment interface, and silicone debris was assessed using a scanning electron microscope (SEM), and the surface roughness (Sa and Sz) was analyzed with a confocal optical microscope. A descriptive and bivariate analysis was conducted. Results: The postimplantoplasty surfaces were significantly smoother than the original implant surfaces. The surface roughness was significantly higher in the US group than in the FS group. Gaps in the implant-abutment interface were infrequent (6.67%; 95% CI = 2.62 to 15.93) and only appeared in the posterior zone. The odds ratio for the presence of residual threads and silicone debris (US group vs FS group) was 7.1 (95% CI = 4.15 to 12.14; P < .001) and 5.53 (95% CI = 3.21 to 9.53; P < .001), respectively. When a prosthetic crown was present, residual threads were 7 times more likely to be found (OR = 7.0; 95% CI = 3.5 to 13.99; P < .001). Conclusions: Implantoplasty leads to a significant reduction in the surface roughness of implants but is affected by several variables. Performing implantoplasty on posterior mandibular implants with adjacent teeth seems to be more challenging compared to implants placed in the anterior region of a fully edentulous maxilla. The presence of a prosthetic crown should also be considered as a relevant factor. Furthermore, implantoplasty can sometimes cause gaps in the implant-abutment interface and an accumulation of silicone debris, especially in areas with limited access.

Accuracy of dental implant placement with or without the use of a dynamic navigation assisted system: A randomized clinical trial.

OBJECTIVES: To assess dental implant placement accuracy with a dynamic computer-assisted implant surgery (dCAIS) system and a freehand approach. Secondarily, to compare the patients' perception and quality of life (QoL) with the two approaches. METHODS: A double-arm randomized clinical trial was conducted. Consecutive partially edentulous patients were randomly allocated to the dCAIS or standard freehand approach groups. Implant placement accuracy was evaluated by overlapping the preoperative and postoperative Cone Beam Computer Tomographs (CBCT) and recording linear deviations at the implant apex and platform (in mm) and angular deviations (in degrees). Questionnaires recorded self-reported satisfaction, pain and QoL during surgery and postoperatively. RESULTS: Thirty patients (22 implants) were enrolled in each group. One patient was lost to follow-up. A significant difference (p < .001) in mean angular deviation was found between the dCAIS (4.02°; 95% CI: 2.85 to 5.19) and the FH (7.97°; 95% CI: 5.36 to 10.58) groups. Linear deviations were significantly lower in the dCAIS group, except for the apex vertical deviation, where no differences were found. Although dCAIS took 14 min longer (95% CI: 6.43 to 21.24; p < .001), patients in both groups considered the surgical time acceptable. Postoperative pain and analgesic consumption during the first postoperative week were similar between groups and self-reported satisfaction was very high. CONCLUSION: dCAIS systems significantly increase the accuracy of implant placement in partially edentulous patients in comparison with the conventional freehand approach. However, they increase the surgical time significantly and do not seem to improve patient satisfaction or reduce postoperative pain.

Effect of Implantoplasty on Roughness, Fatigue and Corrosion Behavior of Narrow Diameter Dental Implants.

Implantoplasty (IP) is used in dental implants with peri-implantitis and aims to remove threads and polish rough surfaces in order to prevent bacterial colonization. As a result of this procedure, implant strength might be compromised. We tested 20 tapered screw-shaped Ti6Al4V dental implants with a simulated bone loss of 50%. Ten implants underwent IP and 10 served as controls. Surface topography (Sa, Sz, Ssk, and Sdr) was analyzed with a confocal optical microscope. Subsequently, a minimum of four series of cyclic loads were applied with a servo-hydraulic mechanical testing machine (5 × 106 cycles at 15 Hz, between a maximal nominal value-starting at 529 N in the IP group and 735 N in the control group-and 10% of that force). We recorded the number of cycles until failure and the type of failure. Implant failure was analyzed by visual inspection and scanning electron microscopy. Open circuit potential and potenctiodynamic tests were carried out with high precision potentiostat using Hank's solution at 37 °C to evaluate the effect of the implantoplasty on the corrosion resistance. Implantoplasty significantly reduced the surface topography values (median) and interquartile range (IQR); Sa from 1.76 (IQR = 0.11) to 0.49 (IQR = 0.16), Sz from 20.98 (IQR = 8.14) to 8.19 (IQR = 4.16), Ssk from 0.01 (IQR = 0.34) to -0.74 (IQR = 0.53) and Sdr from 18.20 (IQR = 2.26) to 2.67 (IQR = 0.87). The fatigue limits of the control and implantoplasty groups were 551 N and 529 N, respectively. The scanning electron micrographs showed fatigue striations indicating fatigue failure. Besides, the fractographic analysis revealed a typical brittle intergranular fracture mechanism. The infinite life range of the dental implants evaluated was largely above the threshold of usual chewing forces. Implantoplasty seems to render a fairly smooth surface and has a limited impact on fatigue resistance. In addition, implantoplasty produces a decrease in the corrosion resistance of the implant. Corrosion current density from 0.019 µA/cm2 for as-received to 0.069 µA/cm2 in the interface smooth-roughened dental implant. These places between the machining and the rough area of the implant are the most susceptible, with the appearance of pitting.

Ion release and local effects of titanium metal particles from dental implants: An experimental study in rats.

BACKGROUND: The objective of this study was to evaluate the accumulation of ions in blood and organs caused by titanium (Ti) metal particles in a mandibular defect in rats, together with a description of the local reaction of oral tissues to this Ti alloy debris. METHODS: Twenty Sprague-Dawley rats were randomly distributed into three groups: an experimental group with a mandibular bone defect filled with metallic debris obtained by implantoplasty; a positive control group; and a negative control group. Thirty days after surgery, the rats were euthanized and perilesional tissue surrounding the mandibular defect was removed, together with the lungs, spleen, liver, and brain. Two blood samples were collected: immediately before surgery and before euthanasia. The perilesional tissue was histologically analyzed using hematoxylin-eosin staining, and Ti, aluminum, and vanadium ion concentrations in blood and organs were measured by TQ-ICP-MS. Descriptive and bivariate analyses of the data were performed. RESULTS: All rats with implanted metal debris showed metal particles and a bone fracture callus on the osseous defect. The metal particles were surrounded by a foreign body reaction characterized by the presence of histiocytes and multinucleated giant cells (MNGCs). The experimental group had a significant higher concentration of Ti ions in all studied organs except lung tissue (p < 0.05). In addition, there were more V ions in the brain in the experimental group (p = 0.008). CONCLUSIONS: Although further studies are required to confirm the clinical relevance of these results, Ti metal particles in the jaw might increase the concentration of metal ions in vital organs and induce a foreign body reaction.

Comparison of external, internal flat-to-flat, and conical implant abutment connections for implant-supported prostheses: A systematic review and network meta-analysis of randomized clinical trials.

STATEMENT OF PROBLEM: The implant abutment connection interface has been considered one of the major factors affecting the outcome of implant therapy. However, drawbacks of traditional meta-analyses are the inability to compare more than 2 treatments at a time, which complicates the decision-making process for dental clinicians, and the lack of a network meta-analysis. PURPOSE: The purpose of this network meta-analysis was to assess whether the implant abutment connection influences the outcome of implant-supported prostheses. MATERIAL AND METHODS: An electronic search was undertaken to identify all randomized clinical trials comparing the effect of at least 2 different implant abutment connection designs published from 2009 up to May 2020. Outcome variables were implant survival rate, peri-implant marginal bone loss, and biologic and prosthetic complication rates at 12 months after prosthetic loading. Relevant information was extracted, and quality and risk of bias assessed. Pairwise meta-analyses and network meta-analyses based on a multivariate random-effects meta-regression were performed to assess the comparisons (α=.05 for all analyses). RESULTS: For peri-implant marginal bone loss and prosthetic complications, conical interfaces were determined to be the most effective, with significant differences when compared with external hexagonal connections (P=.011 and P=.038, respectively). No significant differences were found among the implant abutment connections in terms of survival and biologic complications (P>.05 in all direct, indirect, and mixed comparisons). CONCLUSIONS: After 1 year of loading, conical connections showed lower marginal bone loss and fewer prosthetic complications than external hexagonal connections. However, the implant abutment connection design had no influence on the implant survival and biologic complication rates.

Evaluation of the inflammatory and osteogenic response induced by titanium particles released during implantoplasty of dental implants.

Implantoplasty is a mechanical decontamination technique that consists of removing the threads and polishing and smoothing the dental implant surface. During implantoplasty there is a large release of titanium metal particles that might provoke a proinflammatory response and reduce the viability of osteogenic cells. We analyze the inflammatory and osteogenic response induced by Ti6Al4V particles released during implantoplasty and by as-received commercially pure Ti particles. Macrophages stimulated with metal particles obtained by implantoplasty and with as-received Ti particles showed an increased proinflammatory expression of TNF-α and a decreased expression of TGF-ß and CD206. Regarding cytokine release, there was an increase in IL-1ß, while IL-10 decreased. The osteogenic response of Ti6Al4V extracts showed a significant decrease in Runx2 and OC expression compared to the controls and commercially pure Ti extracts. There were no relevant changes in ALP activity. Thus, implantoplasty releases metal particles that seems to induce a pro-inflammatory response and reduce the expression of osteogenic markers.

Is serum C-terminal telopeptide cross-link of type 1 collagen a reliable parameter for predicting the risk of medication-related osteonecrosis of the jaws? A systematic review and meta-analysis of diagnostic test accuracy.

OBJECTIVE: To determine the usefulness of Serum C-terminal telopeptide cross-link of type 1 collagen (sCTX) as a preoperative marker for predicting the risk of developing medication-related osteonecrosis of the jaws (MRONJ) after invasive oral surgery in patients on antiresorptive medication. MATERIALS AND METHODS: Two authors independently searched four electronic databases up to March 25, 2021, for case-control studies and prospective and retrospective cohort studies that assessed preoperative sCTX levels in patients taking antiresorptive medication who underwent oral surgery procedures. The main outcome was the number of MRONJ cases in patients with an sCTX value lower and higher than 150 pg/mL. Qualitative and quantitative data was extracted in tables and the risk of bias was assessed using the QUADAS-2 tool. Estimates of diagnostic accuracy were expressed as sensitivity, specificity, negative and positive likelihood ratio (LR - and LR +), and diagnostic odds ratio (DOR), with a 95% confidence interval (95%CI). The data were combined using random-effects models based on the inverse variance method. RESULTS: Seven studies were included in the meta-analysis. The results were as follows: sensitivity 57% (95%CI: 41-71%), specificity 72% (95%CI: 64-79%), LR + 2 (95%CI: 1.3-3.1), LR - 0.6 (95%CI: 0.4-0.9), and DOR 3.4 (95%CI: 1.5-7.7). CONCLUSIONS: The low overall performance of sCTX indicates that this parameter is not suitable for predicting MRONJ risk in patients on antiresorptive medication who need an oral surgery procedure. CLINICAL RELEVANCE: sCTX should not be considered a reliable preoperative marker to predict MRONJ development.

Retrospective Cohort Study on the Influence of Bone Remodeling on Marginal Bone Loss and Peri-implantitis Around Immediately Loaded Implants Supporting Complete-Arch Restorations.

PURPOSE: The main objective of this study was to assess the influence of bone remodeling on late marginal bone loss in immediately loaded, implant-supported, complete-arch restorations and, secondarily, to determine its relationship to peri-implant disease occurrence using a multilevel analysis. MATERIALS AND METHODS: A retrospective cohort study of patients treated consecutively in a private clinic with immediately loaded full-arch restorations with at least 12 months of follow-up was conducted. Bone remodeling and marginal bone loss were determined through measurements made on panoramic radiographs by two calibrated examiners. Peri-implant health status was diagnosed in a visit for peri-implant maintenance. Descriptive, bivariate, and multilevel analyses were performed with Stata/IC 15.1 software (StataCorp). RESULTS: A total of 30 patients (11 men and 19 women, mean age: 63.3 ± 10.4 years), with a mean follow-up of 37.7 ± 19.6 months were included. Forty arches (20 maxillary and 20 mandibular) received 207 implants. Bone remodeling had an inversely proportional effect on marginal bone loss (P =.005) but was not related to peri-implantitis (P =.103; hazard rate [HR] = 2.1). CONCLUSION: Taking into account the limitations of this study, bone remodeling around immediately loaded dental implants supporting complete-arch restorations does not appear to increase marginal bone loss or peri-implantitis.

Physicochemical and Biological Characterization of Ti6Al4V Particles Obtained by Implantoplasty: An In Vitro Study. Part I.

Implantoplasty is a mechanical decontamination technique that consists of polishing the supra-osseous component of the dental implant with peri-implantitis. This technique releases metal particles in the form of metal swarf and dust into the peri-implant environment. In the present in vitro study, the following physicochemical characterization tests were carried out: specific surface area, granulometry, contact angle, crystalline structure, morphology, and ion release. Besides, cytotoxicity was in turn evaluated by determining the fibroblastic and osteoblastic cell viability. As a result, the metal debris obtained by implantoplasty presented an equivalent diameter value of 159 µm (range 6-1850 µm) and a specific surface area of 0.3 m2/g on average. The particle had a plate-like shape of different sizes. The release of vanadium ions in Hank's solution at 37 °C showed no signs of stabilization and was greater than that of titanium and aluminum ions, which means that the alloy suffers from a degradation. The particles exhibited cytotoxic effects upon human osteoblastic and fibroblastic cells in the whole extract. In conclusion, metal debris released by implantoplasty showed different sizes, surface structures and shapes. Vanadium ion levels were higher than that those of the other metal ions, and cell viability assays showed that these particles produce a significant loss of cytocompatibility on osteoblasts and fibroblasts, which means that the main cells of the peri-implant tissues might be injured.

Mechanical Properties and Corrosion Behavior of Ti6Al4V Particles Obtained by Implantoplasty: An In Vitro Study. Part II.

In the field of implant dentistry there are several mechanisms by which metal particles can be released into the peri-implant tissues, such as implant insertion, corrosion, wear, or surface decontamination techniques. The aim of this study was to evaluate the corrosion behavior of Ti6Al4V particles released during implantoplasty of dental implants treated due to periimplantitis. A standardized protocol was used to obtain metal particles produced during polishing the surface of Ti6Al4V dental implants. Physicochemical and biological characterization of the particles were described in Part I, while the mechanical properties and corrosion behavior have been studied in this study. Mechanical properties were determined by means of nanoindentation and X-ray diffraction. Corrosion resistance was evaluated by electrochemical testing in an artificial saliva medium. Corrosion parameters such as critical current density (icr), corrosion potential (ECORR), and passive current density (iCORR) have been determined. The samples for electrochemical behavior were discs of Ti6Al4V as-received and discs with the same mechanical properties and internal stresses than the particles from implantoplasty. The discs were cold-worked at 12.5% in order to achieve the same properties (hardness, strength, plastic strain, and residual stresses). The implantoplasty particles showed a higher hardness, strength, elastic modulus, and lower strain to fracture and a compressive residual stress. Resistance to corrosion of the implantoplasty particles decreased, and surface pitting was observed. This fact is due to the increase of the residual stress on the surfaces which favor the electrochemical reactions. The values of corrosion potential can be achieved in normal conditions and produce corroded debris which could be cytotoxic and cause tattooing in the soft tissues.

Peripheral giant cell granuloma associated with a dental implant: A case report.

Peripheral giant cell granuloma (PGCG) is a reactive exophytic lesion classified as a benign tumor of the oral mucosa. Although its etiology is not clear, it may be a consequence of local chronic irritation or persistent trauma. The objective of this case report was to document the main clinical and histopathological characteristics of a patient with a PGCG associated with a dental implant. A 36 years-old man presented a partly-ulcerated violet-colored sessile-based tumor in the buccal aspect of an implant placed in the fourth quadrant. Radiographically, the implant had one third of marginal bone loss. Differential diagnosis included PGCG and pyogenic granuloma. The implant and the lesion were removed and the histopathological diagnosis was PGCG. After 6 months, there was no evidence of relapse. Peripheral giant cell granulomas may appear in implants that have suffered bone loss. When facing with peri-implant soft tissue lesions, it is advisable to perform an anatomopathological study to obtain a correct diagnosis, to establish an adequate treatment plan, and to rule out malignant lesions. Key words:Peri-implant bone loss, peripheral giant cell granuloma, benign tumor.

The Influence of Implantoplasty on Surface Roughness, Biofilm Formation, and Biocompatibility of Titanium Implants: A Systematic Review.

PURPOSE: A review was done to evaluate the effect of implantoplasty on surface roughness, biofilm formation, and biocompatibility of dental implants. MATERIALS AND METHODS: Electronic searches were done in PubMed (OVID), Scopus, Web of Science, and The Cochrane Library to identify all relevant articles published until April 2020. All publications evaluating changes in implant surfaces after implantoplasty were included. The primary outcome variable was roughness of the implant surface. Secondary outcome variables were biofilm elimination and regrowth, changes in surface elements, and cell viability. RESULTS: A total of 11 in vitro studies and two in vivo publications were included. Implantoplasty reduced surface roughness of the implant. The final outcome depended on the bur protocol, with tungsten carbide burs providing the smoothest surfaces, followed by silicone polishers. Implantoplasty did not affect cell viability, and roughness was inversely correlated to human gingival fibroblast growth. The technique also proved effective in removing biofilm and preventing its regrowth. CONCLUSION: Implantoplasty reduces the surface roughness of dental implants, which in turn inhibits biofilm formation without affecting the biocompatibility of titanium implants. Since most of the included studies were done in an in vitro setting, further clinical trials are necessary to confirm these outcomes.

Patient perception about the need for antibiotics after tooth extractions: A cross-sectional study.

BACKGROUND: Although the current scientific literature does not support the routine use of antibiotics after dental extractions, patients believe that these drugs offer clear benefit during the postoperative period. The main objective of this study was to describe patient perception of the need for antibiotics after routine tooth extraction and to assess knowledge about the benefits and adverse effects of antibiotic therapy. MATERIAL AND METHODS: A cross-sectional study was carried out. A total of 452 participants requiring tooth extraction and seen in the Dental Clinic of the University of Barcelona (Barcelona, Spain) were given a specific questionnaire on the need for antibiotics after dental treatments or diseases, and on their benefits and adverse effects. Descriptive bivariate and multivariate (logistic regression model) analyses were performed. RESULTS: Of the 452 participants, 185 (40.9%) were men and 267 (59.1%) were women, with a mean age of 35.2 ± 15.9 years. Most of the patients (76.6%) expected to take antibiotics after tooth extraction. A higher level of education, older age and knowledge about bacterial resistances were inversely correlated to the perceived need for antibiotic treatment (p<0.05). According to the respondents, the main advantage of antibiotics was the reduction of infection rates, while the most frequently mentioned adverse events were allergic reactions, diarrhea and nausea or vomiting. CONCLUSIONS: Most patients think that antibiotics are necessary after routine dental extraction to prevent postoperative infection. Younger patients with a low educational level and who are unaware of the problem posed by bacterial resistances seem to be more supportive of antibiotic prophylaxis. Most respondents are familiar with the main benefits and adverse effects of these drugs. Key words:Antibiotic, microbial drug resistance, tooth extraction, oral surgery, survey, postoperative wound infection.

Accuracy assessment of dynamic computer-aided implant placement: a systematic review and meta-analysis.

OBJECTIVES: To assess the accuracy of dynamic computer-aided implant surgery (dCAIS) systems when used to place dental implants and to compare its accuracy with static computer-aided implant surgery (sCAIS) systems and freehand implant placement. MATERIALS AND METHODS: An electronic search was made to identify all relevant studies reporting on the accuracy of dCAIS systems for dental implant placement. The following PICO question was developed: "In patients or artificial models, is dental implant placement accuracy higher when dCAIS systems are used in comparison with sCAIS systems or with freehand placement? The main outcome variable was angular deviation between the central axes of the planned and final position of the implant. The data were extracted in descriptive tables, and a meta-analysis of single means was performed in order to estimate the deviations for each variable using a random-effects model. RESULTS: Out of 904 potential articles, the 24 selected assessed 9 different dynamic navigation systems. The mean angular and entry 3D global deviations for clinical studies were 3.68° (95% CI: 3.61 to 3.74; I2 = 99.4%) and 1.03 mm (95% CI: 1.01 to 1.04; I2 = 82.4%), respectively. Lower deviation values were reported in in vitro studies (mean angular deviation of 2.01° (95% CI: 1.95 to 2.07; I2 = 99.1%) and mean entry 3D global deviation of 0.46 mm (95% CI: 0.44 to 0.48 ; I2 = 98.5%). No significant differences were found between the different dCAIS systems. These systems were significantly more accurate than sCAIS systems (mean difference (MD): -0.86°; 95% CI: -1.35 to -0.36) and freehand implant placement (MD: -4.33°; 95% CI: -5.40 to -3.25). CONCLUSION: dCAIS systems allow highly accurate implant placement with a mean angular of less than 4°. However, a 2-mm safety margin should be applied, since deviations of more than 1 mm were observed. dCAIS systems increase the implant placement accuracy when compared with freehand implant placement and also seem to slightly decrease the angular deviation in comparison with sCAIS systems. CLINICAL RELEVANCE: The use of dCAIS could reduce the rate of complications since it allows a highly accurate implant placement.

Probing single-tooth dental implants with and without prostheses: a cross-sectional study comparing healthy and peri-implant mucositis sites.

AIM: To evaluate differences in probing depth (PPD) with and without a prosthesis in implants without interproximal bone loss (IBL). Secondarily, to assess whether the difference in PPD measured with and without the crown was affected by diagnosis or implant location. MATERIALS AND METHODS: A cross-sectional study was conducted in patients with a single screw-retained implant-supported crown in the posterior area, without IBL. PPD and was assessed before and after crown removal. A subgroup analysis compared healthy vs. mucositis implants and premolar vs. molar locations. RESULTS: In the 62 implants analysed (23 healthy and 39 with mucositis), the PPD was 1.15 mm (SD = 1.24 mm) deeper without the prosthesis than with it (p < .001). This difference was independent of the implant location (p > .05) except for buccal sites (p = .048). The mean PPD difference for implants with mucositis was 0.95 mm (SD = 1.19 mm; p < .001) while healthy implants had a mean PPD variation of 1.47 mm (SD = 1.29 mm; p < .001). CONCLUSION: The presence of prosthesis in single-tooth implants in the posterior area without IBL seems to lead to an underestimation of PPD that appears to be significant in implants diagnosed with mucositis, although the difference is even greater in healthy implants. Further studies are needed to confirm these findings.

Mechanical complications of implant-supported complete-arch restorations and impact on patient quality of life: A retrospective cohort study.

STATEMENT OF PROBLEM: Mechanical complications (for example, fractures) in implant-supported complete-arch restorations may affect the social and professional activities of the patient. However, most studies seem to overlook patient perceptions and generally do not assess the changes in the quality of life (QoL) of patients who experience these complications. PURPOSE: The purpose of this retrospective cohort study was to assess the influence of technical or mechanical complications of complete-arch implant-supported prostheses on patient perception and QoL by using the Oral Health Impact Profile (OHIP)-14. MATERIAL AND METHODS: A retrospective cohort study was formed of patients treated consecutively at a private clinic with immediately loaded complete-arch prostheses supported by a minimum of 4 implants (Replace Tapered; Nobel Biocare AB) and Multi-Unit conical abutments (Multi-Unit abutments; Nobel Biocare AB). OHIP-14 and questions regarding self-reported satisfaction were used to evaluate the influence of mechanical complications on QoL. RESULTS: Fifty-six participants (26 men and 30 women) with a mean age of 64 ±11.1 years, and 72 restored arches were included. The mean ±standard deviation follow-up time was 52 ±26 months. The prosthetic success rate was 38.8%, and the survival rate was 100% (no failure was registered). The most common complications were abutment screw loosening (43%), chipping or fracture of the veneering material (25%), and screw loosening (21%). The OHIP-14 scores were close to zero, without differences between participants with or without mechanical complications. Overall, the participants reported that the prostheses allowed good oral hygiene (94.6%) and met their expectations (89%) and that they would repeat the treatment (87.5%) and would recommend it to others (93%). CONCLUSIONS: Minor mechanical complications such as screw loosening and chipping or fracture of the veneering material were frequent events but had no impact on the satisfaction and QoL of patients with immediately loaded complete-arch implant-supported prostheses.