Fortunato Alfonsi

The Effect of Insertion Torque on the Clinical Outcome of Single Implants: A Randomized Clinical Trial

BACKGROUND The insertion torque value has been extensively used as an indicator for implant primary stability, which is considered a determining parameter for the implants success. PURPOSE The primary goal of the present randomized clinical trial was to evaluate and compare the clinical outcome for implants placed with high insertion torque (between 50 Ncm and 100 Ncm) and regular insertion torque (within 50 Ncm) in healed ridges. MATERIALS AND METHODS Partially edentulous patients, missing one or more mandibular or maxillary teeth, having an adequate amount of bone, requiring implant placement, were randomized to receive Blossom CT implants with regular insertion torque (<50 Ncm) or CT implants with high insertion torque (≥50 Ncm). Implants were left to heal submerged for 3 months. Implants were restored with individualized abutments and cemented metal-ceramic crowns. Acquired measurements were: insertion torque values (IT), thickness of buccal bone plate after implant osteotomy preparation (BBT), marginal bone level (MBL), and facial soft tissue level (FST). All patients were followed 12 months after implant placement. RESULTS One hundred sixteen implants were placed in one hundred sixteen patients and enrolled for the study. Fifty-eight implants were randomly allocated in regular-IT and high-IT groups with a mean insertion torque ranging from 20 Ncm to 50 Ncm and from 50 Ncm to 100 Ncm, respectively. Three implants failed, and another five implants showed at the 12-month evaluation a marginal bone loss (ΔMBL) greater than 1.5 mm, being considered unsuccessful. CONCLUSIONS The findings suggested that implants inserted with high-IT (≥50 Ncm) in healed bone ridges showed more peri-implant bone remodeling and buccal soft tissue recession than implants inserted with a regular-IT (<50 Ncm). Moreover, sites with a thick buccal bone wall (≥1 mm) - after implant osteotomy site preparation - seemed to be less prone to buccal soft tissue recession after 12 months than sites with a thin buccal bone wall (<1 mm).

Buccal bone deficiency in fresh extraction sockets: a prospective single cohort study

OBJECTIVE The purpose of this prospective single cohort study was to evaluate the use of xenograft and collagen membranes in treating full or partial buccal bone defects of fresh extraction sockets in the esthetic zone. MATERIALS AND METHODS Thirty-three patients requiring tooth extraction in the anterior maxillary area and showing a complete or partial buccal bone plate deficiency (more than 2 mm) were consecutively enrolled and treated. Corticocancellous porcine bone and platelet-rich fibrin (PRF) with a collagen membrane were used to graft the extraction sockets, and the membranes were left exposed to the oral cavity with a secondary soft tissue healing. The outcome variables were as follows: width of keratinized mucosa, facial soft tissue levels, clinical bone changes (measured with a clinical splint), implant and prosthesis failures, and peri-implant marginal bone changes. RESULTS All treated sites allowed the placement of implants; the width of keratinized mucosa at the mid-facial aspect showed an increase of 2.3 mm 5 months after the grafting procedure, and its value was 3.2 ± 0.6 mm at 1-year follow-up. The mean values of the facial soft tissue level indicated an increase over time. The bone level showed an improvement of 0.8 ± 0.1 mm and 0.7 ± 0.1 mm at mesial and distal sites, respectively, when compared to the baseline measurements. Finally, in the palatal area, no bone changes were observed. No implant failed during the entire observation period. CONCLUSIONS Findings from this study showed that xenograft and PRF, used for ridge preservation of the extraction sockets with buccal bone plate dehiscence in the esthetic zone, can be considered effective in repairing bone defects before implant placement. The secondary soft tissue healing over the grafted sockets did not compromise bone formation; moreover, the soft tissue level and the width of keratinized gingiva showed a significant improvement over time.

Tissue Stability of Implants Placed in Fresh Extraction Sockets: A 5-Year Prospective Single-Cohort Study

BACKGROUND Several materials have been used for ridge preservation after tooth extraction. This 5-year prospective single-cohort study is aimed at evaluating the success rate, marginal bone level (MBL), soft tissue stability, and subjective patient evaluation of implants placed in fresh extraction sockets with the use of a flapless technique and a xenograft to treat the peri-implant bone defect. METHODS Patients requiring a single implant in fresh extraction sockets were selected. After flapless extraction and implant insertion, the peri-implant bone defect was grafted with porcine bone. Collagen membrane was used to stabilize the graft. Four months later, a second surgery and prosthetic procedures were performed. Clinical parameters (width of keratinized gingiva [WKG], facial soft tissue level [FST], papilla index, plaque index, and bleeding on probing) were measured, and periapical radiographs were taken at the time of implant placement (baseline) and then at 1, 3, and 5 years thereafter. Image analysis software was applied to measure changes in the marginal bone level (ΔMBL). Additionally, patient satisfaction regarding the implant treatment was evaluated. All analyses were collected and measured by an independent, trained observer. Together with descriptive statistics, for each of the outcome variables, pairwise comparisons were performed using the Wilcoxon signed-rank test for matched samples. The level of statistical significance was set at 0.01 for all analyses. RESULTS Forty-seven consecutive patients were treated, with an implant survival rate at 5 years of 95.7%. ΔMBL showed statistically significant differences: mean values were -0.68 ± 0.39, -0.94 ± 0.44, and -1.08 ± 0.43 mm at the 1, 3, and 5-year follow-up, respectively. Changes in WKG (ΔWKG) and FST (ΔFST) decreased from the 1-year point of the survey (0.80 ± 0.79 and 0.71 ± 0.73 mm for ΔWKG and ΔFST, respectively) to the last follow-up check at 5 years (0.67 ± 0.74 and 0.56 ± 0.69 mm for ΔWKG and ΔFST, respectively), with no significant differences. The papilla indexes showed significant differences among the baseline and all the other time points. Concerning patient satisfaction, at the last survey time point, 74% ± 11.8% of patients were satisfied regarding the overall implant treatment, 73.0% ± 11.1% gave a favorable opinion regarding the appearance of the peri-implant soft tissues, and 80.5% ± 11.3% judged positively the finished appearance of the implant crown. No significant differences were obtained among the three follow-up times. CONCLUSIONS The data of the present study suggest that the placement of a dental implant by means of a flapless technique in a fresh extraction socket filled with slowly resorbable graft biomaterial and with a delayed prosthetic restoration shows positive final esthetic outcomes. At the 5-year point of the survey, the changes in the bone level were minimal. Moreover, both midfacial tissue and the papillae maintained the early increase recorded before the first year of the follow-up.

Molecular, Cellular and Pharmaceutical Aspects of Filling Biomaterials During the Management of Extraction Sockets

After a tooth extraction both hard and soft tissues undergo dimensional changes. The use of a ridge preservation technique at the moment of the tooth extraction could help could help to prevent the volume loss, thus simplifying the subsequent prosthetic and/or implant therapy. Some studies were conducted in order to examine the biomaterials and the surgical technique used for ridge preservation procedures. Clinical, histological, volumetric and molecular outcomes were registered and analyzed in different studies, in order to comprehend the biological events and the consequences of a socket preservation procedure and to allow the clinician to make the correct choice.

Longitudinal analysis on the effect of insertion torque on delayed single implants: A 3-year randomized clinical study

BACKGROUND Implant stability is commonly related to insertion torque. Recently, it has been suggested that higher insertion torque may lead to greater bone resorption. PURPOSE The aim of the present randomized clinical study was to evaluate the role of different insertion torque values in terms of implant success, marginal bone loss, and facial soft tissues recession. MATERIALS AND METHODS Patients requiring a single dental implant were recruited and randomized to receive one of two implants with the same macro-geometry but different cutting designs. First group consists of a 90 degrees cutting groove know as self-tapping implant, and the second group known as Blossom™ cutting groove. (Intra-Lock, Boca Raton, Florida). The insertion torque (IT) was assessed and two groups followed: high-IT (≥50 Ncm) group and regular-IT (<50 Ncm) group. After 3 months, all the implants were restored. At baseline, buccal bone thickness (BBT) was recorded. During the 3-year survey, the following outcomes had been registered: implant failures and success, radiographic marginal bone level around dental implant (MBL) and facial soft tissue level (FSTL). RESULTS A hundred and sixteen implants were placed in healed sites. The overall survival rate after 3 years was 96.5%. The Cumulative Success Rate was 91.3% for the High IT group and 98.2% for the Regular IT group. The mean marginal bone loss and facial soft tissue recession, at a 3-year evaluation, were significantly greater for the High-IT group and in the mandible than that reached in the Regular-IT group and in the maxilla. CONCLUSION Present findings showed that implants placed with higher insertion torque in mandible led to greater bone resorption and mucosal recession than that registered for implants placed with a regular IT. Moreover, sites with a thick buccal bone wall (≥1 mm) showed smaller recession at the facial soft tissue level after 3 years.

Gene Expression of Human Mesenchymal Stem Cells Cultured on Titanium Dental Implant Surfaces.

Objective: The study shows how the influence of titanium surfaces on human mesenchymal stem cells differentiates toward osteocytes lineage and how, after growth, on machined titanium disk or etched titanium disk, changes, in gene expression for RUNX1, CTNNB1, SP7, and DLX5. Methods: Genes were analyzed by means of quantitative real-time polimerase chain reaction. Osseo genic lineage differentiation was also tested by means of the catenin-&bgr;1 immunofluorescence, induced osteoblasts, which represented the internal control. Results: The RUNX1 and SP7 expressions in the induced osteoblasts prove to be different, compared with cells cultured on metallic supports. Moreover, the levels of expression of the runt-related transcription factor 1 and the osterix appeared more down-regulated in cells that grew on a machined titanium surface. In the present experimental model, mRNA expression of DLX5 and CTNNB1 in human mesenchymal stem cells, cultured on each of the titanium surfaces, showed no differences, compared with osteoblast-induced cells. The immunofluorescence scores, for protein expression of beta-catenin in human mesenchymal stem cell treated cells, illustrates significantly improved results with the etched surface. Conclusions: Present results suggested that different titanium surfaces might induce some differences in terms of gene expression. The only gene analyzed, which proved significant differences between the 2 titanium supports, was SP7; however, the other 3 genes indicating the existence of differences between the 2 titanium groups.

Clinical outcomes of implants placed in ridge-preserved versus nonpreserved sites: A 4-year randomized clinical trial

BACKGROUND Consistent bone changes occur after tooth removal, often compromising the success of implants placed within the socket left to natural healing The long-term effect of ridge preservation on implant outcomes is still unclear. PURPOSE The aim of the study was to assess success and survival rates of implants placed in extraction sockets, with spontaneous healing, or grafted with cortical porcine bone, or collagenated corticocancellous porcine bone. MATERIALS AND METHODS Ninety patients in need for a single premolar/molar tooth extraction and an implant treatment were selected for the present study. Patients were randomly distributed among 3 groups: sites that healed naturally (ctrl), or sites that received ridge preservation with either cortical (cort) or collagenated corticocancellous porcine bone (coll). Three months after, all the experimental sites were reentered to insert implants. Marginal bone levels were recorded; soft tissues were analyzed and summarized with the Pink Esthetic Score (PES). Forty-two patients out of 90 (initial cohort study) completed the entire follow-up of 4 years. RESULTS Cumulative survival and success rates for all implants were 100% at a 4-year evaluation. Mean marginal bone loss (MBL) was 1.14 ± 0.23 mm in the cort group, 1.13 ± 0.29 mm in the coll group, and 1.92 ± 0.07 mm in the ctrl group. There were no significant differences between the 2 grafting materials but MBL was significantly greater in the nongrafted sites (P value < .001). The PES resulted significantly better (9.42 ± 0.75) for the cort group than for the coll group (8.53 ± 1.18) and ctrl group (6.07 ± 1.89) at 4-year evaluation. CONCLUSIONS Ridge preservation was more effective than natural healing in preserving marginal bone and in achieving better esthetic outcomes around implants 4 years after placement. The cortical porcine bone showed better clinical outcomes than collagenated corticocancellous porcine bone.

Surgical Treatment of Oroantral Communications

Background:Oroantral communication (OAC) can be defined as a pathologic space created between the maxillary sinus and the oral cavity.This communication and subsequent formation of a chronic oroantral fistula is a common complication often encountered by oral and maxillofacial surgeons.Although various techniques have been proposed in published studies, long-term successful closure of oroantral fistulas is still one of the most difficult problems confronting the surgeon working in the oral and maxillofacial region.The decision of which treatment modality to use is influenced by many factors, such as the amount and condition of tissue available for repair, the size and location of the defect, the presence of infection, the time to the diagnosis of the fistula. Objective:To evaluate an alternative technique for the treatment of oro-antral fistula, using a combined therapeutic ear nose and throat/intraoral approach. Methods:Twelve consecutive patients affected by complicated OAC were included in this study.The protocol consisted of: clinical, endoscopic, and radiological preoperative evaluation (panoramic tomogram and computed tomography); systemic antibiotic and steroid therapy for 2 weeks before surgery; one-stage surgical procedure consisting of Functional Endoscopic Sinus Surgery technique associated with the closure of the OAC by a titanium mesh and a mucoperiosteal flap; postoperative antibiotic and cortisone-based therapy.A titanium mesh was used to obtain an optimal support and stabilization of soft tissues.Follow-up consisted of weekly clinical evaluation during the first month, a clinical evaluation at 1, 3, 6, 12, 24 months and a nasal endoscopy at 3, 8, 24 weeks after surgery. A second surgical step took place to remove the mesh, after a period of healing, which went from 6 to 18 months. Samples were harvested from the surgical site after mesh removal for histological analysis. Results:At 1 month follow-up, in 10 patients of 12, the Valsalva manoeuvre was negative, same result at the 3rd month follow-up, although in 11 of 12 patients. In 5 of 12 patients, the mesh was exposed. The histological analysis confirmed the formation of a pseudo-periosteum layer.One patient failed because the mesh lost its stability. The patient was operated again 8 months later and new mesh was fixed into place. Conclusion:The current study showed that one-stage, combined endoscopic and intraoral approach represents a feasible and minimally invasive procedure for the long-term effective treatment of chronic complicated OACs.The main advantage of the use of a titanium mesh to guide the regeneration is that it assures a predictable healing, mechanic scaffold, tissues stability and allows a possible following oral rehabilitation.