Erythritol powder airflow for the treatment of peri-implant mucositis: A randomized controlled clinical trial.

OBJECTIVES: Peri-implant mucositis is a biofilm-related, reversible inflammatory disease that can evolve into peri-implantitis if not adequately treated. The aim of the present randomized controlled clinical trial was to evaluate the efficacy of air-abrasive powder as compared to chlorhexidine (CHX) for the treatment of peri-implant mucositis, in terms of clinical and patient-reported outcomes (PROMs) and occurrence of peri-implantitis 12 months after treatment. METHODS: In the control group, full-mouth calculus and plaque removal was performed with ultrasound and manual devices, and a 1.0% CHX gel was applied; in the test group, supra- and subgingival biofilm removal was performed using erythritol powder with a dedicated nozzle and calculus removal was performed with ultrasonic instruments if needed. Bleeding and plaque indexes, peri-implant probing depth and tissue level were measured at 1 week, and 1, 3, 6 and 12 months after treatment, while PROMs were evaluated up to 7 days after treatment. RESULTS: Among 80 included implants, 70 were analysed at 12 months follow-up (30 in the test group, 40 in the control group, and 20 subjects). Success rates (implant-level) in terms of bleeding index were significantly different between the test (96.7%) and control group (92.5%); as for PROMs, only taste sensation was significantly better in the test group. The test group was significantly correlated to the smallest changes in peri-implant probing depth between baseline and 3 months. CONCLUSIONS: The study showed that both treatment strategies are effective. This suggests that the use of air-abrasive powders could be used as an alternative biofilm removal method instead of adjunctive treatments with antiseptics.

Avoiding implant-related complications in medically compromised patients with or without unhealthy lifestyle/Elevated oxidative stress.

Increased human life expectancy broadens the alternatives for missing teeth and played a role in the widespread use of dental implants and related augmentation procedures for the aging population. Though, many of these patients may have one or more diseases. These systemic conditions may directly lead to surgical complications, compromise implant/bone healing, or influence long-term peri-implant health and its response to biologic nuisances. Offering patients credible expectations regarding intra- and postoperative complications and therapeutic prognosis is an ethical and legal obligation. Clear identification of potential types of adverse effects, complications, or errors is important for decision-making processes as they may be related to different local, systemic, and technical aspects. Therefore, the present review structures the underlying biological mechanisms, clinical evidence, and clinical recommendations for the most common systemic risk factors for implant-related complications.

How to avoid intraoperative and postoperative complications in maxillary sinus elevation.

Maxillary sinus floor elevation, via the lateral approach, is one of the most predictable bone augmentation procedures performed in implant dentistry. but both intra- and postoperative complications can occur, and some of them are severe. Our aim is as follows: To review the pertinent literature on the topic, especially assessing the risk factors related to complications. To give clinical recommendations to minimize intra- and postoperative complications with the ultimate scope of improving the standard of clinical care and patient safety.

Laser treatments as an adjunct to non-surgical periodontal therapy in subjects with periodontitis and type 2 diabetes mellitus: a systematic review and meta-analysis.

OBJECTIVES: Periodontal disease and diabetes have an extensively investigated bidirectional correlation. Non-surgical periodontal treatment (NSPT) was proven to contribute to glycemic control. Moreover, it may benefit from the association of adjunctive therapies. The aim of the present systematic review is to assess the clinical efficacy of NSPT in association with laser (LT) or photodynamic therapy (PDT) in controlled or uncontrolled diabetic patients, and to grade the level of evidence. MATERIALS AND METHODS: Randomized controlled clinical trials with at least 3-month follow-up were searched in MEDLINE via OVID, EMBASE, and Cochrane Central, screened for inclusion, and grouped based on the performed treatments, follow-up time, type of diabetes, and level of glycemic control. RESULTS: Eleven RCTs with 504 total subjects were included. The adjunct of PDT showed a statistically significant 6-month difference in PD changes (with low certainty of evidence), but not in CAL changes, while a significant difference in 3-month PD and CAL changes was found with the adjunct of LT (low certainty of evidence). Patients treated with PDT registered a higher decrease in HbA1c levels at 3 months, but no significant difference was noted at 6 months; LT also led to better HbA1c changes at 3 months with a moderate certainty of evidence. CONCLUSION: Despite the promising short-term HbA1c decrease, the results should be interpreted with caution due to the small effect sizes and the statistical heterogeneity, and further evidence from well-designed RCTs is needed to support the routine use of PDT or LT in adjunct to NSPT.

The influence of implant position and of prosthetic characteristics on the occurrence of peri-implantitis: a retrospective study on periapical radiographs.

OBJECTIVE: The present retrospective study aimed to investigate the influence of malposition on the occurrence of peri-implantitis. MATERIALS AND METHODS: The study included clinical records of systemically healthy patients with single and partial implant-supported rehabilitations and at least 1-year post-loading follow-up. The parameters collected included implant-related factors, patient-related factors, site-related factors, and prosthesis-related factors. The radiographic measurements were taken by using a dedicated software and the diagnosis of peri-implantitis was made based on all the available clinical and radiographic data. Descriptive statistics were provided for all variables. Following an exploratory approach, an implant-level analysis of factors influencing the occurrence of peri-implantitis was done through a multilevel multivariate logistic regression (mixed). RESULTS: A total of 180 implants belonging to 90 subjects were randomly selected. Malposition showed no statistically significant association with the occurrence of peri-implantitis. According to the multi-level analysis, the parameters that were significantly associated with peri-implantitis included presence / history of periodontitis (OR = 5.945, 95% CI: 1.093 - 32.334, P = 0.039) and presence of an emergence profile angle ≥ 45° (OR = 9.094, 95% CI: 2.017 - 40.995, P = 0.005). CONCLUSIONS: Implant malposition, as defined following Buser's criteria (2004), did not influence the occurrence of peri-implantitis in the selected cohort. Conversely, history of periodontitis and presence of a prosthetic emergence profile with an angle ≥ 45° were correlated to an increased risk of peri-implantitis.

Mechanical Resistance of a 2.9-mm-Diameter Dental Implant With a Morse-Taper Implant-Abutment Connection.

Among the complications that can occur at dental implants, the fracture of any implant component is a relatively infrequent but clinically relevant problem. Because of their mechanical characteristics, small diameter implants are at higher risk of such complication. The aim of this laboratory and finite element method (FEM) study was to compare the mechanical behavior of a 2.9- and 3.3-mm-diameter implant with a conical connection under standard static and dynamic conditions, following the International Organization for Standardization (ISO) 14801:2017. Finite element analysis was performed to compare the stress distribution on the tested implant systems under a 300-N, 30° inclined force. Static tests were performed with a load cell of 2 kN; the force was applied on the experimental samples at 30° with respect to the implant-abutment axis, with an arm of 5.5 mm. Fatigue tests were performed with decreasing loads, at 2-Hz frequency, until 3 specimens survived without any damage after 2 million cycles. The emergence profile of the abutment resulted the most stressed area in finite element analysis, with a maximum stress of 5829 and 5480 MPa for 2.9- and 3.3-mm-diameter implant complex, respectively. The mean maximum load resulted in 360 N for 2.9-mm-diameter and 370 N for 3.3-mm-diameter implants. The fatigue limit was recorded to be 220 and 240 N, respectively. Despite the more favorable results of 3.3-mm-diameter implants, the difference between the tested implants could be considered clinically negligible. This is probably due to the conical design of the implant-abutment connection, which has been reported to present low stress values in the implant neck region, thus increasing the fracture resistance.

Influence of implant diameter on implant survival rate and clinical outcomes in the posterior area: a systematic review and meta-analysis.

OBJECTIVE: The aim of the present systematic review was to test the hypothesis that the diameter of implants inserted in the posterior area affects implant survival rate, prosthetic survival rate and peri-implant parameters (bleeding on probing (BoP), marginal bone loss (MBL), pocket probing depth (PPD)). MATERIALS AND METHODS: An electronic search of studies published until December 2021 was done on three databases (Pubmed, Scopus, Cochrane) independently by two authors. Clinical trials comparing implant survival rate, BoP, MBL and PPD among narrow diameter implants (NDI: ≥ 3.0 mm to < 3.75 mm) and regular diameter implants (RDI ≥ 3.75 mm to < 5 mm) were included. Data were independently extracted by two reviewers. Risk of bias was evaluated according to the Cochrane risk-of-bias tool for randomized studies and to the Joanna Briggs Institute Critical Appraisal tools for non-randomized ones. A pair-wise meta-analysis was conducted on the included studies. RESULTS: Seven articles were included out of the 4291 identified from the digital research. Overall, a total of 939 implants were inserted (319 NDI, 620 RDI). Only one study was judged at serious risk of bias. No statistically significant difference was found in implant survival rate (risk ratio 1.01 (95% CI [0.98 to 1.04], P = 0.67)) while the difference was significant for BoP (mean difference 2.89 (95% CI [0.30 to 5.48] mm, P = 0.03)) with higher values for NDI. Higher MBL was identified among regular diameter implants (mean difference -0.15 mm (95% CI [-0.32 to 0.01 mm], P = 0.07). No statistically significant differences were identified for prosthetic survival and PPD. CONCLUSIONS: No differences were found in implant survival rate between narrow and regular implants. A higher BoP was identified among narrow implants, but there was no higher bone loss. It is not possible to draw definitive conclusions about the use of narrow-diameter implants in the posterior region.

The effect of the use of proton pump inhibitors, serotonin uptake inhibitors, antihypertensive, and anti-inflammatory drugs on clinical outcomes of functional dental implants: A retrospective study.

OBJECTIVE: The present retrospective study investigated the effect of chronic intake of proton pump inhibitors, selective serotonin uptake inhibitors, anti-inflammatory, and antihypertensive drugs on the survival of dental implants and on the occurrence of peri-implantitis. MATERIALS AND METHODS: Survival analyses for implant failure and peri-implantitis were performed patient level for each drug subcategory and for risk factors. The HR for each drug was calculated with adjusted models as compared with a control group made of subjects not assuming the specific drug. Multilevel logistic regression was used to explore the influence of implant-level and patient-level variables on the outcomes. RESULTS: A total of 270 subjects receiving 1118 dental implants were included, with a mean follow-up time of 5.19 ± 4.22 years. After 10 years, the survival rate was 86.9% (patient level), and according to survival analysis, 61.3% of subjects were free from peri-implantitis. The use of anti-inflammatory medicines produced a significant effect (p = .04) on peri-implantitis as compared to subjects not using the drug, with a 2.7-year drop in the mean survival time. The HR was slightly above the level of significance in a semiadjusted model (p = .058). The multilevel analysis found a significant effect on the entire sample and not when considering only subjects with implants with more than 1-year follow-up. CONCLUSIONS: We found a possible relationship between anti-inflammatory drug use and the occurrence of peri-implantitis in the examined cohort of patients, and no correlation for the other drugs.

Frequency and anatomic variability of the mandibular lingual foramina: a cone-beam CT study.

BACKGROUND: To evaluate the distribution of lingual foramina (LF) and their correlation with demographic characteristics and mandible width, shape, and bone thickness in Caucasian Italian patients subjected to cone-beam CT (CBCT). METHODS: CBCTs were reviewed to assess the number of all LF, midline and lateral LF. We also assessed the relationship of the number of lateral LF with gender and mandibular width, shape, and bone thickness using the Chi Square test. A p value < 0.05 was considered statistically significant. RESULTS: Three-hundred patients (180 males; age range: 21-87 years) were included. The highest frequency per patient was of 2 LF (97/300, 32.3%), followed by 3 (81/300, 27%) and 4 (53/300, 17.7%). No LF were observed in 2/300 patients (0.7%), while the highest number was of 8 LF in one patient. The highest frequency of midline LF per person was of 2 LF (57.3%, 172/300), while the highest number per person was 5 LF in one patient (0.3%). The highest frequency of midline LF located above and below the genial tubercle was of 1 in 197/300 patients (65.7%) and in 169/300 patients (56.3%), respectively. Concerning lateral LF, the highest frequencies were of 0 (113/300, 37.7%) and of 1 (112/300, 37.3%). We did not observe any significant difference of the number of midline and lateral LF based on gender (P = .438 and P = .195, respectively) or mandible width (P = .069 and P = .114, respectively). The mandible shape was normal in 188 cases, with facial constriction in 42, lingual constriction in 54, and hour glass constriction in 16. The mean bone thickness was 10.76 mm in the symphysis, 10.92 mm in the right hemiarches, and 10.68 in the left hemiarches. No significant differences in the distribution of LF were observed also based on mandibular shape and bone thickness (both with P > .05). CONCLUSIONS: We have shown the high variability of number and anatomic distribution of LF in an Italian group of patients subjected to CBCT without reporting any association with gender and mandible width, shape, and bone thickness.

EFFICACY OF 67% SODIUM BICARBONATE TOOTHPASTE FOR PLAQUE AND GINGIVITIS CONTROL: A SYSTEMATIC REVIEW AND META-ANALYSIS.

OBJECTIVE: Previous studies demonstrated a dose-dependent efficacy of sodium bicarbonate when added to dentifrices for the mechanical control of dental biofilm. The present systematic review and meta-analysis aimed to evaluate the efficacy of a 67% sodium bicarbonate-based toothpaste for gingival health parameters improvement in subjects with gingivitis. MATERIALS AND METHODS: An electronic search on MEDLINE, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL), was performed using a combination of keywords, followed by a hand search on pertinent Journals. Randomized controlled trials (RCTs) and prospective comparative studies in English language were included. There was no publication date and language restriction. The data regarding gingival, bleeding, and plaque index were extracted from the selected studies. Included studies underwent risk-of-bias assessment. When at least 3 studies reporting the same outcome were found, a meta-analysis was undertaken, to estimate the combined effect. Trial Sequential Analysis (TSA) was also performed to evaluate the power of the meta-analysis for primary outcomes. RESULTS: The search strategy yielded 83 articles. After screening, 7 RCTs were included. Three were at high risk, one at moderate risk, and 3 at low risk-of-bias. Significant improvement of gingival index, bleeding index, and plaque index was observed in patients using 67% sodium bicarbonate toothpaste as compared with control subjects. TSA showed sufficient power for modified Gingival index and bleeding scores. CONCLUSIONS: The clinical use of 67% sodium bicarbonate toothpaste can improve periodontal health in patients with gingivitis.

Ten years follow-up retrospective study on implant survival rates and prevalence of peri-implantitis in implant-supported full-arch rehabilitations.

OBJECTIVES: The aim of the present paper was to present medium- and long-term data on implant survival and on the prevalence of peri-implantitis in a cohort of patients treated with full-arch rehabilitations. MATERIALS AND METHODS: Clinical records of all patients treated with immediately loaded full-arch rehabilitation in the Dental Clinic of the IRCCS Istituto Ortopedico Galeazzi in Milan, Italy, supported by moderately rough implants were retrospectively examined to calculate survival curves for implant loss and for the occurrence of peri-implantitis (both at implant- and at patient level). Regression methods were used to evaluate the correlation between the presence of periodontitis and smoking habits with the outcomes. RESULTS: A total of 384 implants placed in 77 patients (96 rehabilitations) were evaluated for a mean period of 8.0 years (range 1.0-13.7 years) from loading. After 10 years, the cumulative survival rate was 96.11% (95% CI: 99.17%-93.05%; 84 implants) while the cumulative rate of implants free from peri-implantitis was 86.92% (95% CI: 82.14%, 91.71%; 60.69% [95% CI: 44.19%, 77.19%] at patient level). The cumulative proportion of implants without peri-implantitis after 10 years was significantly higher in mandible (89.76%, 95% CI: 84.49%, 95.03%) than in maxilla (81.71%, 95% CI: 71.91%, 91.51%; p = 0.028). No correlation was found between periodontal and smoking status and outcomes. CONCLUSIONS: The study reported high 10-year implant survival rate for full-arch rehabilitations since implant loss was relatively rare. Peri-implantitis was relatively frequent in the examined population although the number of subjects available for 10-year evaluation was limited.

Autologous Platelet Concentrates in Treatment of Furcation Defects-A Systematic Review and Meta-Analysis.

BACKGROUND: The aim of this review was to evaluate the adjunctive effect of autologous platelet concentrates (APCs) for the treatment of furcation defects, in terms of scientific quality of the clinical trials and regeneration parameters assessment. METHODS: A systematic search was carried out in the electronic databases MEDLINE, SCOPUS, CENTRAL (Cochrane Central Register of Controlled Trials), and EMBASE, together with hand searching of relevant journals. Two independent reviewers screened the articles yielded in the initial search and retrieved the full-text version of potentially eligible studies. Relevant data and outcomes were extracted from the included studies. Risk of bias assessment was also carried out. The outcome variables, relative to baseline and post-operative defect characteristics (probing pocket depth (PPD), horizontal and vertical clinical attachment loss (HCAL, VCAL), horizontal and vertical furcation depth (HFD, VFD) were considered for meta-analysis. RESULTS: Ten randomized trials were included in this review. Only one study was judged at high risk of bias, while seven had a low risk, testifying to the good level of the evidence of this review. The meta-analysis showed a favorable effect regarding all outcome variables, for APCs used in adjunct to open flap debridement (p < 0.001). Regarding APCs in adjunct to bone grafting, a significant advantage was found only for HCAL (p < 0.001, mean difference 0.74, 95% CI 0.54, 0.94). The sub-group analysis showed that both platelet-rich fibrin and platelet-rich plasma in adjunct with open flap debridement, yielded significantly favorable results. No meta-analysis was performed for APCs in combination with guided tissue regeneration (GTR) as only one study was found. CONCLUSION: For the treatment of furcation defects APCs may be beneficial as an adjunct to open flap debridement alone and bone grafting, while limited evidence of an effect of APCs when used in combination with GTR was found.

Erythritol/chlorhexidine combination reduces microbial biofilm and prevents its formation on titanium surfaces in vitro.

BACKGROUND: The purpose of this in vitro study was to evaluate the antibiofilm activity of a novel air-polishing powder consisting of erythritol and chlorhexidine, assessing its ability to reduce previously grown microbial biofilm and to prevent biofilm formation on titanium surfaces. METHODS: Clinical strains of Staphylococcus aureus, Pseudomonas aeruginosa, Bacteroides fragilis and Candida albicans isolated from peri-implantitis lesions were used. Biofilm was grown on sandblasted titanium discs and treated with erythritol/chlorhexidine. The antimicrobial activity was evaluated by determining the minimum inhibitory concentration and the minimum microbicidal concentration. The antibiofilm activity was assessed by semiquantitative spectrophotometric assay and by confocal laser scanning microscopy. RESULTS: Erythritol/chlorhexidine displayed an inhibitory and a microbicidal activity against all the tested strains. The spectrophotometric analysis showed that the treatment was effective in both reducing the previously developed biofilm and decreasing biofilm formation on titanium surfaces. Confocal laser scanning microscopy analysis showed a significant reduction of the total biofilm volume, with an increase of the percentage of dead cells of all the microorganisms tested. CONCLUSIONS: Erythritol/chlorhexidine displayed significant antimicrobial and antibiofilm activity against microorganisms isolated from peri-implantitis lesions. Due to its properties, it might represent a promising approach for the prevention and treatment of peri-implant diseases associated to microbial biofilm infections.

Prevalence of Peri-Implant Mucositis and Peri-Implantitis in Patients Treated with a Combination of Axial and Tilted Implants Supporting a Complete Fixed Denture.

OBJECTIVES: The aim of this retrospective study was to assess the incidence and prevalence of peri-implant mucositis and peri-implantitis in patients with a fixed full-arch prosthesis supported by two axial and two tilted implants. MATERIALS AND METHODS: Sixty-nine patients were included in the study. Each patient received a fixed full-arch prosthesis supported by two mesial axial and two distal tilted implants to rehabilitate the upper arch, the lower arch, or both. Three hundred thirty-six implants for 84 restorations were delivered. Patients were scheduled for follow-up visits every 6 months in the first 2 years and yearly after. At each follow-up visit peri-implant mucositis and peri-implantitis were diagnosed if present. RESULTS: The overall follow-up range was from 12 to 130 months (mean 63,2 months). Three patients presented peri-implantitis. The prevalence of peri-implant mucositis ranged between 0 and 7,14% of patients (5,06% of implants) while the prevalence of peri-implantitis varied from 0 to 4,55% of patients (3,81% of implants). CONCLUSIONS: The prevalence and incidence of peri-implant mucositis and peri-implantitis are lower than most of the studies in literature. Therefore this kind of rehabilitation could be considered a feasible option, on the condition of adopting a systematic hygienic protocol.

Platelet-Rich Plasma and Deproteinized Bovine Bone Matrix in Maxillary Sinus Lift Surgery: A Split-Mouth Histomorphometric Evaluation.

PURPOSE: The purpose of this split-mouth controlled study was to evaluate and compare the amount of vital bone after lateral sinus lift surgery using either a mixture of pure platelet concentrate and deproteinized bovine bone mineral (test group) or solely deproteinized bovine bone as grafting material (control group). MATERIALS AND METHODS: Six patients with edentulous posterior maxilla and a residual ridge height of less than 4 mm were recruited in this study. Six months after grafting procedure, 2 bone biopsies per patient were taken bilaterally from the anterolateral sinus wall. Histological and histomorphometrical analysis was carried out. RESULTS: A total of 10 sinus surgeries in 5 patients were analyzed. The mean percentage of vital bone was 22.72% ± 9.21% (range, 11.45%-33.30%) in the control group and 30.70% ± 7.89% (range, 18.30%-39.99%) in the test group. CONCLUSION: The adjunct of pure platelet-rich plasma to deproteinized bovine bone mineral may enhance vital bone formation in the first 6 months after sinus floor augmentation. However, no statistically significant difference was found between groups (P = 0.18).

Horizontal bone augmentation in full-arch maxillary implant-supported restorations: a preliminary clinical report.

PURPOSE: The purpose of this study was to describe a technique for horizontal maxillary bone grafting in combination with implant placement for full arch. MATERIALS AND METHODS: Patients requiring complete rehabilitation of the edentulous maxillae were included. Two axial mesial implants and 2 tilted distal ones were placed approximately 2 mm buccally about the centre of the bone crest. A graft made of a mixture of deproteinized bovine bone and platelet-rich plasma was placed buccally covering bony dehiscence. Horizontal bone gain and differences in bone volume were evaluated 6 months after surgical intervention, at the time of prosthetic loading, through comparison of standardized cone beam computed tomographic scans. RESULTS: A total of 10 patients were consecutively treated after the proposed protocol. After 6 months, the mean horizontal bone gain was 1.87 ± 0.54 mm for the left side and 1.79 ± 0.78 mm for the right side without any significant difference between them. The bone volume increased by 610.5 ± 27.57 mm after 6 months. CONCLUSIONS: It can be postulated that the proposed protocol may provide a significant horizontal bone gain for minimizing the anterior cantilever in full-arch prosthesis.

The Morphology of Peri-Implantitis Bone Defects: A Retrospective Study on Periapical Radiographs.

Objectives: The aims of this study were to assess the morphologic features of peri-implant defects, as measured on 2D intraoral radiographs, and to investigate the possible correlation between such morphology and other parameters related to the position and characteristics of the implant or the implant-supported prosthesis. Materials and Methods: Implants with peri-implantitis were included in this retrospective study. Data collected were related both to the patients and to the position/characteristics of the implants and the implant-supported prosthesis. Measurements of the morphologic defects were performed by two operators on digitalized intraoral periapical radiographs. Results and Conclusion. In total, 73 implants in 27 patients were included. The measurements of the periapical radiograph suggested that the most common defect conformation was crateriform, with both intraosseous and horizontal components. An inverse correlation was found between the extension of the peri-implant lesion and the time between the radiographic assessment and the implant placement. The total lesion area was strongly correlated to oral hygiene levels. No correlations between lesion extension and smoking, diabetes, history of periodontal were found. In conclusion, the results from this 2D radiographic study showed the prevalence of crateriform peri-implant defects, with a hygiene-correlated extension, perceptible on the mesial and distal aspects; 3D imaging could be used when available for further research and clinical investigation.

The Correlation between Intraorifice Distance and the Anatomical Characteristics of the Second Mesiobuccal Canal of Maxillary Molars: A CBCT Study.

Introduction: Missing anatomy is one of the main causes of endodontic failures, and accurate knowledge of teeth anatomy is a prerequisite for adequate root canal treatment. The aim of the present cone beam computed tomography (CBCT) study was to describe the anatomical characteristics of the mesiobuccal (MB) root canals of maxillary molars and to understand if a correlation exists between the position of the canal orifices and the anatomical features of the root. Methods: For the purposes of the study, a total of 100 CBCT scans of maxillary molars with two MB canals were selected and studied. The features of root canal anatomy of the MB root of the same teeth were analyzed and recorded (root length, confluence, and Vertucci classification). The distance between MB1 and MB2 orifices and the palatal orifice were recorded, as well as the distance between the orifices and the line joining the palatal orifice and the others. A statistical analysis was performed by providing descriptive measures, the measure of the correlation between different parameters, and the influence of some of these measures on the presence of a confluence between MB1 and MB2. Results: It resulted that the most frequent configuration is type II Vertucci. The length measured on the sagittal plane was significantly correlated to the presence of a confluence in the MB root. When the root length was higher than 14.56 mm, the confluence is three times more frequent than when the length is lower (OR = 3.635). The area under the curve (AUC) of the receiver operator characteristic (ROC) curve for length on the sagittal plane was 0.632 (P=0.036). Conclusions: The presence of a confluence between the MB canals of maxillary molars is correlated to the length of the root that could be measured on the sagittal plane and to the distance between the canal orifices. The relative position of the root canal orifices in relation to anatomic landmarks needs to be further explored.

CAD/CAM Titanium Meshes for GBR: A Case Series with Preliminary Histologic Analysis.

Titanium has been proposed as a mesh material for guided bone regeneration (GBR) since the 1990s. To overcome difficulties in shaping and adapting meshes to the defect, digital techniques were introduced to digitally print meshes capable of fitting the bone perfectly, reproduced through the patient's CT scan. Five patients were included in this case series, and their CBCT data were acquired and sent to the producer of the titanium meshes. 3D regenerative surgery was performed with titanium meshes and a mix of demineralized bovine bone matrix (DBBM) and autogenous bone (1:1 ratio). Radiographic measures were evaluated on paraxial sections of the CBCT through a dedicated software. When possible, regenerated bone samples were obtained at implant insertion. Four out of five regenerated areas healed without local or systemic complications. One mesh was removed after 2 months and 2 weeks due to exposure. The mean vertical bone gain was 4.3 ± 1.5 mm (range: 2.5 to 7 mm). Two histologic samples were obtained. In sample 1, bone tissue area and graft material area were 44.4% and 12.5%, respectively; in sample 2, the same parameters were 15.6% and 16.9%, respectively.