Simultaneous implant placement and restoration with guided bone regeneration in the mandibular anterior region.

BACKGROUND: Restoring the mandibular anterior teeth by implants can be difficult due to potential complications arising from using prosthetic implant connections that are larger than the incisors at the cementoenamel junction level. METHODS: This retrospective study is aimed at determining the survival and esthetic outcomes of anterior mandible implants immediately placed and restored in patients diagnosed with stages 3-4 periodontitis. The study included 75 implants that were inserted along with guided bone regeneration in 42 patients. Over a follow-up period of 3 to 8 years (mean of 6.95 ± 1.78 years), the study evaluated esthetic, marginal bone loss (MBL), and biological and prosthetic complications. RESULTS: No failures were recorded during the follow-up period; after eight years, the survival rate was 100%. Patient's age and gender did not have a statistically significant impact on MBL, but smokers had a greater MBL than non-smokers at the 8-year (2.98 mm vs. 1.23 mm, respectively, p = 0.016) time-point. At 3 years, only 13.3% of the implants had mesial papillae, 36.0% had distal papillae, and 16.0% had the cervical metallic part of the abutment exposed. Peri-implantitis was diagnosed in 20.7% of the patients at the 8-year follow-up time. CONCLUSIONS: Based on the limitations of this study, immediate placement and restoration of the mandibular incisors can be a feasible procedure, but only a few implants achieved the complete restoration of the papillae.

Risk factors contributing to early implant failure following sinus augmentation: A study of a challenging cohort.

BACKGROUND: Sinus augmentation has become a more predictable and successful procedure as the knowledge of its indications and complications increased. However, knowledge of risk factors leading to early implant failure (EIF) among challenging systemic and local conditions is insufficient. OBJECTIVES: The present study aims to assess risk factors for EIF following sinus augmentation in a challenging cohort. METHODS: A retrospective cohort study conducted during a period of 8 years in a tertiary referral centre providing surgical and dental health care. Implant and patient variables including age, ASA (American Society of Anesthesiology) physical status classification, smoking, residual alveolar bone, type of anaesthesia and EIF were collected. RESULTS: Cohort was comprised of 751 implants placed in 271 individuals. EIF rates at the implant and patient level were 6.3% and 12.5%, respectively. EIF was found to be higher among smokers (patient level: χ2 (1) = 8.74, p = .003), ASA 2 physical classification patients (patient level: χ2 (2) = 6.75, p = .03), sinuses augmented under general anaesthesia (patient level: χ2 (1)=8.97, p = .003), higher bone gain (implant level: W = 12 350, p = .004), lower residual alveolar bone height (implant level: W = 13 837, p = .001) and multiple implantations (patient level: W = 3016.5, p = 0.01). However, other variables such as age, gender, collagen membrane and implant's dimensions did not reach significance. CONCLUSIONS: Within the limits of the study, we can conclude that smoking, ASA 2 physical status classification, general anaesthesia, low residual alveolar bone height and numerous implants are risk factors for EIF following sinus augmentation in challenging cohorts.

The Effect of Proton Pump Inhibitors on Early Implant Failure A Retrospective Cohort Study.

Background and Objectives: Maintenance of a firm and long-term stable osseointegration is the primary goal of implant dentistry. Time is used to define implant failure characteristics. Early implant failure (EIF) occurs up to one year after loading. Recent studies indicated an association between proton pump inhibitors (PPI) therapy and failure of osseointegration. The present study assessed whether the use of PPIs is a risk factor to EIF. Materials and methods: A retrospective cohort study including 687 patients and 2971 dental implants. The study group (PPIs users) comprised 17.3% (119) individuals and 18.7% (555) implants. The remaining cohort (82.7% (568) individuals and 81.3% (2416) implants) served as control. The information was taken from the patients' files. The following information was collected: age, gender, physical status, systemic diseases, HbA1C values before and after implant-supported prosthesis delivery in cases of diabetes mellitus, smoking, implant location, number of implants per individual, bone augmentation, implant brand, length and width, and EIF. EIF was defined as implant removal within a period of up to 12 months from loading. Results: EIF in PPIs vs. non-PPIs users was 19.3% vs. 14.3% (p = 0.16) at patient level and 5.4% vs. 3.5% at implant level (p = 0.03). Univariate analysis yielded factors significantly associated with PPIs use, including older age, physical status of the American Society of Anesthesiology (ASA) 3, hypertension, hyperlipidemia, diabetes mellitus, osteoporosis, cardiovascular accident (CVA), location (anterior mandible), shorter and narrower implants, and higher number of implants per individual. Multivariate analysis yielded statistically significant OR of 1.91; p = 0.01 for EIF following PPIs use and 2.3; p < 0.001 for location in anterior mandible. Conclusions: Patients and their healthcare providers are advised to carefully consider the potential risks of taking PPIs prior to dental implant surgery. Further research is needed to confirm these risks and elucidate systemic and local factors that may be involved in such outcomes.

Patients' Perception of Recovery after Dental Implant Placement.

Background and Objectives: The success rates of surgical dental implant insertions are high. However, knowledge of patients' recovery is still lacking. "Health-related quality of life" (HRQOL) questionnaires are gaining popularity in all fields of medicine. The present survey assessed the perception of recovery after the surgical placement of dental implants. Materials and Methods: Forty individuals (26 women and 14 men; mean age, 55 ± 12 years) filled a questionnaire evaluating patients' perception of recovery for 7 consecutive days post-surgery. Confounding factors included age, gender, oral habits, smoking, bruxism, bone quality (tactile evaluation) and quantity, implant location, number of implants, implant type, length and diameter, one-stage vs. two-stage, and the need for bone grafting. Results: The most serious difficulties were found in swelling, which became minimal after 5 days, followed by eating everyday food, ability to enjoy everyday food, maximal pain and average pain (3 days); analgesics consumption (2.5 days); limitations in daily routine, mouth opening, and speech (2 days); swallowing and sleep (1.5 days); and, within 1 day, all other measures attained minimal levels. Gender, and implant location (anterior vs. posterior) were significant predictor variables exerting their different characteristic delayed recoveries. Conclusions: (1) Patients should expect, in general, recovery within 4 days after dental implant placement; (2) women will experience a delayed recovery, (3) implants placed in the intercanine area will result in postoperative eating difficulties for nearly one week, and (4) the number of implants placed during the same appointment has no effect on post treatment recovery.

Peri-implant disease affects systemic complete blood count values-an experimental in vivo study.

OBJECTIVES: To assess complete blood count (CBC) dynamics following ligature removal and open flap debridement in experimental peri-implantitis in dogs. MATERIALS AND METHODS: Seven male beagle dogs were included in the study. Four rough-surface implants were placed pair-wise in both sides of the mandible 14 weeks after tooth extraction. Second stage surgery was performed after 14 weeks. Experimental peri-implantitis was initiated 3 weeks later by ligature placement around the healing caps thus facilitating plaque accumulation and inducing inflammation and destruction of peri-implant tissues. Ligature removal and open flap debridement were performed 11 weeks later. The CBC values were compared with baseline after each procedure. Wilcoxon paired tests were conducted in order to identify statistically significant differences between baseline data and values obtained after each procedure. RESULTS: Following experimental peri-implantitis, statistically significant (p < 0.05) increases were noted for white blood cells-WBC (9.62 ± 4.34 vs. 6.48 ± 1.34 cells per microliter of blood × 1000), hemoglobin-Hb (15.25 ± 0.94 vs. 13.52 ± 1.46, grams per deciliter), red blood cells-RBC (7.26 ± 0.79 vs. 5.9 ± 0.61 cells per microliter of blood × 1000), mean corpuscular hemoglobin-MCH (23.64 ± 0.96 vs. 23.16 ± 0.83 picograms/cell), platelets-PLT (349.86 ± 51.05 vs. 277.57 ± 66 cells per microliter of blood × 1000), and mean corpuscular hemoglobin concentration-MCHC (35.83 ± 0.27 vs. 31.04 ± 0.48 grams per deciliter). A statistically significant (p < 0.05) decrease in values was noted only for after ligature removal and open flap debridement. Mean corpuscular volume-MCV values were significantly lower (65.99 ± 2.31 vs. 74.65 ± 2.85 femtoliter) following 1st ligature. Values returned to baseline after open flap debridement. CONCLUSIONS: Within its limits, the present data suggest that experimentally induced peri-implantitis affects CBC values. Following surgical treatment, CBC values returned to normal. Clinical relevance This is the first study suggesting possible relationships between peri-implantitis and CBC values. Future studies, confirming such correlation, may provide an insight into the importance of peri-implant maintenance and treatment to minimize supporting tissues disease and reduce systemic effects.

The dynamics of closure following excisional mid-palatal mucoperiosteal wound in a rat model.

OBJECTIVES: The aim of the present study was to assess macroscopically the time-related dimensional pattern of excisional palatal mucoperiosteal wound closure in rats, concomitantly with microscopic analysis of the density of inflammatory infiltrate and myofibroblasts. MATERIALS AND METHODS: Excisional palatal wounds, 4.2 mm in diameter, were made in twenty-one 2-month-old male Wistar rats. The total area and anteroposterior/laterolateral dimensions of the wounds were measured macroscopically at 1, 2, and 3 weeks post-operatively. In addition, histomorphometry was used for assessment of the intensity of inflammation and density of myofibroblasts in the wound area. RESULTS: A significant decrease was found in the total area and anteroposterior but not the laterolateral dimension of the wounds during the 2nd week. These changes were less prominent in the 3rd week. Three weeks post-operatively, the density of inflammatory infiltrate remained high in the central part of the wound concomitant with a significant increase in the number of myofibroblasts. CONCLUSIONS: We concluded that the second week was the most significant in wound closure, with wound contraction first occurring in an anteroposterior plane followed by the laterolateral plane. The increased inflammatory reaction and changes in the density of myofibroblasts may explain the macroscopic decrease in wound dimensions in a time-related manner. CLINICAL RELEVANCE: These findings emphasize the importance of the amount of soft tissue left at surgery, and suggest that the most appropriate time for the use of healing promoters would be the second post-operative week.

Palatal Wound Healing with Primary Intention in a Rat Model-Histology and Immunohistomorphometry.

BACKGROUND AND OBJECTIVES: Subepithelial connective tissue graft (SCTG) from the palate has been considered as the "gold standard" for the treatment of deep gingival recessions. A single-incision technique was reported to allow primary wound healing. A palatal single incision was performed in a rat model. The present study assessed the histology and histomorphometry of palatal wound healing following surgical closure with primary intention. MATERIALS AND METHODS: Twenty-six 6-month-old male Wistar rats weighing 427-650 g. An incision was made on the maxillary palate. A full thickness flap was raised palatally, and then repositioned and sutured. Two experimental groups: S-Study group, I-Intact control group. Half of the animals were sacrificed 7 days and the remaining 14 days postoperatively. Outcome parameters included-epithelial gap; inflammatory infiltration; vascular fraction, expression of myofibroblasts and stem cell markers within the oral epithelium and stromal cells and physical properties of stromal collagen fibers. Investigations were performed at two time-points (7 and 14 days) during the wound healing process. RESULTS: The epithelial gap closed completely after 14 days. The inflammatory reaction and vascular fraction were relatively low. Surgical trauma downregulated the expression of cytokeratin (CK) 14 and CK 15, which returned to normal after 14 days. Epithelial differentiation was mediated through upregulation of connective tissue sex- determining-region-Y-box2 (SOX2). Epithelial SOX2, CD34, alpha smooth muscle actin (αSMA) and physical properties of stromal collagen fibers were not influenced by the surgical trauma. CONCLUSIONS: Surgical trauma followed by palatal wound healing with primary intention in a rat model heals within 14 days. It induces minimal inflammatory infiltration and vascular proliferation. Epithelization is exerted through promotion of epithelial differentiation from stem cells by connective tissue SOX2.

Sclerotherapy of Vascular Malformations in the Oral Cavity-Minimizing Postoperative Morbidity.

Vascular malformations (VMs) are a wide vascular or lymphatic group of lesions common on the head and neck. The objective of this study was to assess the efficacy and morbidity of sclerotherapy for the treatment of VMs in the oral and perioral area. Special attention was given to factors that may contribute to minimizing postoperative morbidity. Data from 25 patients (32 lesions) with oral VMs submitted to sclerotherapy with monoethanolamine oleate (EAO) were included. A structured form was used to collect data. An arbitrary score was determined to evaluate postoperative morbidity. Each of the following signs or symptoms received one point: pain, swelling, hematoma, ulceration, erythema, transient numbness, and transient itching. Pain and swelling were further divided into mild to moderate (1 point) and severe (2 points). Theoretically, the score was in the range of 0-9. Calculated scores ranged 0-4. The patients were further divided into two groups with scores of 0-1 denoting minimal morbidity (MIN) and 2-4 denoting significant morbidity (SIG). The number of lesions in each morbidity-score group were comparable (MIN 17and SIG 15). There were no statistically significant differences between the groups regarding age, number of applications, or average injection volume per mm lesion. Statistically significant differences were noted regarding gender (p = 0.05), lesion diameter (p = 0.030), total volume of first (p = 0.007) and second application (p = 0.05), and total injected volume (p = 0.03). Factors contributing to the risk for significant morbidity included being male, lesion diameter > 5 mm, volume > 0.3 mL per application, and total injected volume > 0.3 mL. A waiting time of 12 weeks prior to additional EAO application was required in 12 out of 29 lesions for clinical observation of complete regression. It was concluded that sclerotherapy with EAO as monotherapy is easy to apply, safe, and effective within a small number of sessions. Application of <0.3 mL EAO per session, and a waiting time of 12 weeks prior to the second application, would significantly minimize morbidity.

Sinus Augmentation with Simultaneous, Non-Submerged, Implant Placement Using a Minimally Invasive Hydraulic Technique.

Background and objectives: To evaluate whether sinus augmentation, using a minimally invasive implant device, via a non-submerged surgical approach, might negatively influence the outcome. Materials and Methods: A retrospective cohort study was conducted by evaluating patients' files, classifying them into two groups. Fifty patients (22 men 28 women) were included in the study, 25 in each group. The use of an implant device based on residual alveolar ridge height for sinus augmentation, radiographic evaluation, insertion torque, membrane perforation, post-operative healing, and a minimum of 12 months follow-up were evaluated. Results: The mean residual alveolar ridge height was 5.4 mm for the non-submerged group and 4.2 mm for the submerged group. There were no intraoperative or postoperative complications (including membrane perforations). The mean insertion torque was 45 N/cm for the study group and 20 N/cm for the control group. Complete soft tissue healing was observed within three weeks. Mean bone gain height was 8 mm for the study and 9.3 mm for the control group. All implants osseointegrated after 6-9 months of healing time. Mean follow-up was 17.5 months, range 12-36 months. Marginal bone loss at last follow-up was not statistically significantly different: 1 mm in the non-submerged vs. 1.2 mm in the submerged group. Conclusions: Submerged and non-submerged healing following maxillary sinus augmentation was comparable provided residual alveolar ridge height >5 mm and insertion torque >25 N/cm.

Reliability of retrievable cemented implant-supported prostheses.

STATEMENT OF PROBLEM: One of the disadvantages of a cemented implant restoration is the potential difficulty of retrieving it. The restoration may be destroyed during removal. PURPOSE: The purpose of this retrospective clinical study was to assess the long-term survival rates of cemented posterior metal ceramic implant-supported prostheses (ISPs) with a metal screw access hole. MATERIAL AND METHODS: During a 12-year period, 274 cemented ISPs with an abutment screw access hole in the metal framework were assessed and served as the study group, and 119 conventional cemented ISPs (without access hole) served as the control group. Participants were followed every 6 months in the first year and once a year subsequently. Ceramic fracture, screw loosening, and refabrication were the prosthetic outcome parameters evaluated at the recall. The Pearson Chi square and Fisher exact test were used to compare the outcome parameters between the control and study groups. RESULTS: A total of 1005 implants and 393 ISPs were evaluated. Ceramic fracture occurred in 6.6% of the ISPs (6.2% test and 7.6% control). Screw loosening occurred in 3.28% of the test group and 3.36% of the control group. Refabrication of ISPs was done in 2.79% of all restorations, (1.45% test and 6.72% control [P=.012]). CONCLUSIONS: Within the limits of this study, preparing cemented ISPs with a screw access hole in the metal framework improves ISP survival rates over time and lowers the cost of maintenance without increasing the risk for porcelain fracture or screw loosening.

Evaluation of a topical herbal patch for soft tissue wound healing: an animal study.

AIM: This study evaluated the effects of a topical herbal patch (PerioPatch®) for gingival wound healing in a rat model. MATERIALS AND METHODS: A mid-crestal incision was performed on each side of the edentulous anterior maxilla in 48, 6-month-old, Wistar rats. Full-thickness flaps were raised, repositioned and sutured. Four experimental groups were established: herbal patch, placebo patch, no patch and no patch and no surgery. Patches were placed immediately after surgery and replaced every 12 h for the following 3 days. Half of the animals were killed after 5 and the remaining ones after 12 days. Tissue blocks were retrieved and processed for histological and immunohistochemical evaluation. Epithelial gap, collagen contents, amount of macrophages, cellular proliferation and vascular contents were evaluated in the central incision area. Statistical analysis consisted of two-way anova. RESULTS: The herbal patch group presented the smallest epithelial gap at 12 days, the highest collagen content both at 5 and 12 days, a larger number of proliferating cells at day 5 and more numerous blood vessels at day 12. Macrophage number was similar in all groups. CONCLUSION: Herbal patch improved wound healing in this animal model.

Maxillary sinus grafting with autograft vs. fresh frozen allograft: a split-mouth histomorphometric study.

BACKGROUND: Surgical techniques as sinus floor augmentation have made it possible to increase the bone volume of the posterior maxilla so that implant placement may be feasible. A large variety of bone grafting materials have been utilized for sinus floor augmentation. A good alternative is allograft. Fresh frozen bone is harvested from live or cadaveric donors and then immediately frozen and stored at -80 °C. To date, studies about the effect of fresh frozen bone are scarce. OBJECTIVE: Evaluation of new bone formation, following maxillary sinus grafting with autograft vs. fresh frozen allograft. MATERIALS AND METHODS: A split-mouth edentulous design including 15 patients was used. Sinus floor augmentation was carried out using either autogenous bone harvested from the ramus area or fresh frozen bone from allogeneic femoral heads. The choice was determined randomly, using a randomized table. The grafted sinus was left to heal for 6 months. Biopsies were harvested from the lateral wall. The biopsies were used for bone histology and histomorphometric analysis. After collection of the biopsy, dental implants were placed. After a healing period of 6 months, the implants were loaded. RESULTS: Implant survival, histology, and histomorphometry of sinuses grafted with autogenous or fresh frozen bone were similar. The new bone formation took place predominantly around and in-between particles. CONCLUSIONS: The findings of the present study support the use of fresh frozen bone allografts for sinus floor augmentation.

Early Implant Failure in Patients Using Antihypertensive Medications: A Retrospective Cohort Study.

INTRODUCTION AND AIMS: Antihypertensive medications increase osteoblasts differentiation and bone mineral formation. Osseointegration of dental implants depends on new bone formation and remodelling. Consequently, improved osseointegration may be speculated in patients receiving antihypertensive drugs. Aim - Asses the effect of antihypertensive medications on osseointegration of dental implants. METHODS: Retrospective cohort study. All individuals (792) who received at least one dental implant during a 6-year period at a single medical centre. The cohort was divided into three groups: normotensive (74.8% - 593) patients (NT group), hypertensive (23.4% - 185) patients using antihypertensive medications (HTN +med group), and hypertensive patients not using (1.8% - 14) antihypertensive medications (HTN -med group). Interventions-Installation of dental implants by experienced oral and maxillofacial surgeons with or without bone augmentation. Main measures - Early implant failure (EIF) (≤12 months from loading) reflects lack of new bone formation or excessive bone turnover during osseointegration. RESULTS: The study included 792 individuals, 14 in the HTN-med group, 185 in the HTN +med group and 593 in the NT group. At the patient level, the HTN -med group were most likely (P = .041) to experience EIF 28.60% (4/14 patients). Due to the small sample of the HTN -med group, an additional analysis was carried out excluding this group. EIF of 9.70% (18/185 patients) in the HTN +med group was significantly (P = .047) lower than the NT group 14.50% (86/593 patients). 2971 implants were inserted in all study groups, 71.4% (2123) in the NT group, 26.4% (784) in the HTN +med group and 2.2% (64) in the HTN -med group. Collectively, EIF was recorded for 114 (3.84%) implants. In the HTN -med group, EIF of 6.25% (4 implants), was significantly (P < .001) higher than the two other groups. The EIF rate of the HTN +med group was 2.29% (18 implants) which was significantly less than that of the NT group 4.33% (92 implants). Controlling modifying parameters, using antihypertensive medication yielded lower EIF with marginal significance (P = .059) and OR = 0.618. CONCLUSION: Based on statistically significant lower EIF rate found in the HTN +med group, antihypertensive medications may decrease the EIF rate of dental implants. CLINICAL RELEVANCE: Clinicians should be encouraged to treat hypertensive patients with implant-supported prostheses, provided patient compliance regarding medications intake is good.

Analysis of Strain Distribution in Common Clinical Designs of Posterior Implant-Supported Fixed Partial Restorations: Comparison between Six Configurations.

The configuration of implant-supported prostheses is considered to influence the magnitude of stress concentrations, affecting their survival rate. The purpose of this study is to determine, through strain gauge measurements during load application, the dispersion and magnitude of strain concentrations in different implant-supported prosthesis designs. All designs matched those commonly used in posterior partially edentulous states. Three implants were inserted into an epoxy resin model (PLM-4B Vishay Measurements Group Inc., Raleigh, NC, USA), allowing for the delivery of three- and four-unit crowns in different cemented configurations. Loads were applied at vertical and oblique directions over the cast crowns in six different configurations representing various posterior partially edentulous restorations. The readings from the strain gauges adhered to the implant necks' presented data on implant strain. Prostheses including cantilevers showed the highest strain among the three-unit prostheses within the prosthetic complex, and three single units showed the least (8133 µs vs. 201 µs, respectively). Angulated load application also had a role in amplifying the strains recorded, resulting in total strains of between 3.5 and 20 times higher than during vertical loading in all configurations. It can be concluded that the configuration of implant-fixed partial prosthesis changes the loads engaging the restoration, the implant, and, probably, the supporting bone.

Thermal Changes of One-Piece Versus Two-Piece Implants During Setting of an Autopolymerized Acrylic Resin.

Purpose: To evaluate differences in the temperature rise at the cervical area of one-piece vs two-piece implants during the setting of relined provisional crowns. Materials and Methods: A K-type thermocouple was fixed to the coronal thread of 15 one-piece implants and 15 two-piece implants that were mounted on a plexiglass apparatus. Baseline temperature (Bl Temp) was recorded before starting the curing process. The maximum temperature (Max Temp) reached during the process in both implant groups was also recorded. Total heat flux (THF) was calculated as well as the thermal amplitude (Temp-Amp) at the implant surface. Finally, the differences between the implant types were compared using unpaired t test. Results: The increase in temperature from baseline was statistically significantly greater in the one-piece implants than in the two-piece implants (P < .01). Similarly, the THF and Temp-Amp were significantly greater in the one-piece implants compared to two-piece implants (P < .01). Conclusions: The polymerization of PMMA-based resin temporary crowns produces a significant temperature rise in both one-piece and two-piece implants. It is advisable to use two-piece implants to restore immediately loaded implants to reduce the risk to implant surroundings that may occur due to the temperature rise at the implant neck.

The Use of Cancellous Block Allografts for Reconstruction and Following Implant Failure Associated with Severe Bone Loss: A Prospective Survival and Histomorphometric Study.

A failed implant site is prone to reduced alveolar bone volume, both horizontally and vertically. The present study assessed the outcome of using cancellous bone block allografts for ridge reconstruction following the removal of failed implants associated with severe bone loss. Individuals presenting with failed implants and massive bone loss were included. Cancellous bone block allografts were used for reconstruction of the atrophic alveolar ridge. Radiographic evaluation at 6 months postgrafting revealed favorable bone healing, allowing implant placement. Bone biopsy samples were taken during implant placement. Twenty-four blocks and 58 implants were placed in 16 patients. Over a mean follow-up time of 40 ± 15 months, the mean bone gain was 5 ± 0.5 mm horizontally and 7 ± 0.5 mm vertically. Block and implant survival rates were 96% (1 block failed) and 95% (3 implants failed), respectively. Histomorphometrically, the mean percentage of newly formed bone was 40%, with 20% residual cancellous block allograft and 40% marrow and connective tissue. Cancellous bone block allograft is a viable treatment alternative for reconstructing the alveolar ridge to achieve a successful second reimplantation, even in the presence of initial severe bone loss.

The Effect of Anticoagulants on Early Implant Failure: A Retrospective Cohort Study.

BACKGROUND: Anticoagulants (AC) are among the most often prescribed drugs in the world. Data regarding ACs' effect on the osseointegration of dental implants is lacking. PURPOSE: The aim of the present retrospective cohort study was to evaluate the effect of anticoagulants (AC) on early implant failure (EIF). The null hypothesis was that the use of AC increases the incidence of EIF. MATERIALS AND METHODS: The research included 687 patients who underwent 2971 dental implant placements in the department of oral and maxillofacial surgery in Rabin medical center, Beilinson hospital, by specialists in oral and maxillofacial surgery. The study group comprised 173 (25.2%) patients and 708 (23.8%) implants using AC. The rest of the cohort served as a control. A structured form was used to collect data at patient and implant level. EIF was defined as implant failure within a period of up to 12 months from loading. EIF was the primary outcome parameter. A logistic regression model was used to predict EIF. RESULTS: Implants placed in individuals ≥ 80 (odds ratio (OR) = 0.34, p = 0.05), and ASA 2/3 vs. ASA 1 individuals (OR = 0.30, p = 0.02/OR = 0.33, p = 0.03, respectively) had decreased odds of EIF, and implants in those using anticoagulants (OR = 2.64, p = 0.01) had increased odds of EIF. At the patient level, the odds of EIF in ASA 3 (OR = 0.53, p = 0.02) and IHD (OR = 0.40, p = 0.02) individuals decreased. In AF/VF (OR = 2.95, p = 0.01) individuals, EIF odds increased. CONCLUSIONS: Within the limitations of the present study, the use of AC is significantly associated with an increased likelihood of EIF: the OR was 2.64. Future research is required to validate and examine the prospective impact of AC on the osseointegration phenomena.

Referral Patterns of General Dental Practitioners for Implant Surgery Procedures.

PURPOSE: The growing demand for implants has led to their implementation by general dental practitioners (GDPs) in clinical practice. The present study assessed referral patterns of GDPs for the surgical phase of implant dental treatment. MATERIALS AND METHODS: One hundred fifty GDPs were asked to fill out a structured questionnaire containing their demographic data and answer six questions characterising their referral patterns for implant dentistry. RESULTS: Forty-one (41%) percent performed the surgical phase, and 87% provided implant restoration. Gender was the only influencing factor for the surgical phase, as 51.4% of male GDPs and 6.5% of female GDPs performed implant surgery themselves. Experience and practice set-up did not influence the referring decision. Fifty-four percent of the practitioners referred 0 to 5 patients per month, and the chosen specialists were: 80% oral and maxillofacial surgeon, 11% periodontist, and 9% selected a specialist depending on the individual case. The major reasons influencing the referral pattern were the complexity of the surgical procedure, followed by systemic medical compromise of the patient. CONCLUSIONS: Most implant surgeries in Israel are still performed by specialists.

Evaluation of Implant Surface Modification with Nanohydroxyapatite Associated with the Use of L-PRF: In Vivo Study in Rats.

Leukocyte-platelet-rich fibrin (L-PRF) contains growth factors that stimulate bone regeneration. This study evaluated the bone repair in a tibia rat model around two implant surfaces in combination or not with L-PRF by assessing microtomographic and histomorphometric parameters. A total of 48 female rats were used in the study, in which 24 received implants with two types of surface treatments (dual acid etched-DAE or nanohydroxyapatite-nanoHA), and the other 24 received the same mini implants with L-PRF, which was collected by cardiac puncture, centrifugated, and inserted in the bone bed. The animals were euthanized 7 and 30 days after implant placement, and the retrieved samples were prepared for microtomographic and histomorphometric (bone-to-implant contact-BIC; and Bone Area Fraction Occupancy-BAFO) analyses. The adhesion of the nanoHA surface onto the implant surface was investigated by insertion and removal in simulated bone medium (Sawbones). The adhesion evaluation revealed that the loss of nanoHA after this procedure (as measured with SEM) from the implant surface was less than 1%. Overall, the nanoHA surface presented more bone in contact and in proximity to the implant, a higher bone surface/tissue volume fraction, a higher number of bone trabeculae, as well as trabecular separation relative to the DAE surface. Such results were more evident when the nanoHA surface was combined with L-PRF and after 30 days in vivo. The nanoHA surface presented higher BAFO when compared to DAE, with or without association with L-PRF. Therefore, implants with a nanoHA surface potentially benefit from the association to L-PRF.

Evaluation of Two Configurations of Hydroxyapatite and Beta-Tricalcium Phosphate in Sinus Grafts with Simultaneous Implant Installation: An Experimental Study in Rabbits.

BACKGROUND: This study aimed to evaluate peri-implant bone formation in rabbits after sinus grafting mediated by hydroxyapatite and beta-tricalcium phosphate (HA + ß-TCP) in granule or paste configurations, concomitant with immediate implant installation. MATERIAL & METHODS: Thirty-four rabbit maxillary sinuses were grafted with HA + ß-TCP, half of which were applied in a granule and half in a paste composition. Implant placement was performed simultaneously. At 7 and 40 days postoperatively, the animals were euthanized, and samples were prepared for tomographic, microtomographic, histological, histometric (hematoxylin and eosin staining, HE), and immunohistochemical (labeling of transcription factor Runx-2 [RUNX2], vascular endothelial growth factor [VEGF], osteocalcin [OCN], and tartrate-resistant acid phosphatase [TRAP]) analysis. Implant removal torque was also measured. RESULTS: On tomography, maintenance of sinus membrane integrity was observed in both the groups. Higher values of morphometric parameters evaluated by micro-CT were found in the "paste group" after seven days. At 40 days, there were no significant differences between the groups in most of the microtomographic parameters evaluated. In histological sections stained with HE, a higher percentage of newly formed bone was observed in the "granule group" after 40 days. Similar positive immunolabeling was observed for both RUNX2 and OCN in both the experimental groups. TRAP immunolabeling was similar in both groups as well. VEGF labeling increased in the "granule group", indicating a higher osteoconductive potential in this biomaterial. Similar removal torque values were observed in both groups. Thus, the two HA + ß-TCP configurations showed similar healing patterns of simultaneously installed implants adjacent to sinus floor elevation. However, significantly higher bone values were observed for the "granule configuration". CONCLUSIONS: The HA + ß-TCP granules and paste presentations showed favorable long-term healing results, with bone formation in similar quantities and quality adjacent to the implants.