Guided bone regeneration using titanium mesh to augment 3-dimensional alveolar defects prior to implant placement. A pilot study.

OBJECTIVES: To evaluate the outcomes of bone regeneration using a customized titanium mesh scaffold to cover a bone graft for reconstruction of complex defects of the jaws. MATERIALS AND METHODS: 19 large defects were digitally reconstructed using CT scans according to the prosthetic requirements. A titanium mesh scaffold was designed to cover the bone (autologous/bovine bone particulate) graft. At least 6 months after surgery, a new cone-beam CT was taken. The pre- and postoperative CT datasets were then converted into three-dimensional models and digitally aligned. The actual mesh position was compared to the virtual position to assess the reliability of the digital project. The reconstructed bone volumes (RBVs) were calculated according to the planned bone volumes (PBVs), outlining the areas under the mesh. These values were then correlated with the number of exposures, locations of atrophy, and virtually planned bone volume. RESULTS: The mean matching value between the planned position of the mesh and the actual one was 82 ± 13.4%. 52.3% (40% early and 60% late) exposures were observed, with 15.8% exhibiting infection. 26.3% resulted as failures. The amount of reconstructed bone volume (RBV) in respect to PBV was 65 ± 40.5%, including failures, and 88.2 ± 8.32% without considering the failures. The results of the exposure event were statistically significant (p = .006) in conditioning the bone volume regenerated. CONCLUSIONS: This study obtained up to 88% of bone regeneration in 74% of the cases. The failures encountered (26%) should underline the operator's expertise relevance in conditioning the final result.

Posterior jaws rehabilitation with < 7mm-short implants. A review.

INTRODUCTION: The results with shorter and shorter implants have been revolutionizing the implantology scenario and are worthy of being well-analyzed and understood. This review aims to add further knowledge about the last 10-years observation period on < 7mm-short implants in the posterior atrophic jaws, better defining the indication of their use. METHODS: From a Medline database research, systematic reviews, controlled and no- controlled trials (CT, n-CT) with ≥ 3years-follow-ups on <7 mm / ≥ 5mm-short implants (group A), and clinical studies with ≥ 1year-follow-up on 4mm-short implants (group B) were considered. The outcomes, in terms of implant survival rate (SR), marginal bone loss (MBL), and complications were analyzed according to the duration of follow-ups, implant site (maxilla and mandible), type of prosthesis (single crown or splinted units), vertically impaired or normal sites. RESULTS: Thirty-four trials (28 for group A and six for group B) were selected. Group A: a mean follow up of 5,8 (3-10) years came out; pre-and post-loading SR range was 94.4- 100% and 89.6-100%, respectively; the range of MBL was 0.12-1.49; 50% of CT found less statistically significant surgical complications in comparison with standard implants (ST) in reconstructed sites, while major prosthetic problems were recorded with short -implants (SH) in 37.5% of CT; in no atrophied sites, a mean SR range of 86.7-100 % vs. 88-100 % and a total bone loss of 2 vs.1.6 for SH vs.ST emerged. Group B: the overall mean follow-up period was 2,3 years, and the pre-and post- SR ranges were 93-100 % and 87.5-100 %, respectively. The MBL range was 0.02- 0.63 mm. All RCT reported significantly fewer surgical complications with SH than with ST in reconstructed mandibles within one year. No prosthetic complications were reported for up to 5 years using no pontics or cantilevers fixed bridges. CONCLUSIONS: Similar or even better results for SH than ST in terms of post-loading SR and MBL came out for < 7mm/ ≥ 5mm-short implants in atrophic bone regardless of the prosthetic solutions, with less surgical complications but a few more prosthetic problems; the good results up to 5 years for 4mm-short implants in mandibles are associated with splinted and no-risk prosthetic solutions.

A 4 mm-Long Implant Rehabilitation in the Posterior Maxilla with Dynamic Navigation Technology: A Case Report after a Three-Years Post-Loading Follow-Up.

The use of short (<8 mm long) and ultra-short (<6 mm long) implants allows the prosthetic rehabilitation of the posterior ridges of the jaws avoiding reconstructive procedures. Nevertheless, this approach requires vast experience to ensure the primary stability of the fixture in a correct position. Computer-aided implantology (CAI) achieves better results than the free-hand one in terms of placement accuracy, reducing the surgical risks and the operative timings. Dynamic navigation (DN) allows the surgeon to track the position and movements of the drill in real-time on the CT imaging data set. It is more versatile than the computed static system, enabling the operator to change the guidance coordinates according to the intra-operative feedbacks. A mono-edentulous upper right first molar site was rehabilitated with a four mm-long implant to avoid reconstructive techniques, drastically rejected by the patients. The case was managed within a DN protocol considering the minimal available bone and the prosthetic demands. The phases of this procedure were strictly documented up to a 3-year follow-up. No intra-operative problems occurred, and adequate primary stability of the implant was obtained. The prosthetic loading was carried out within only six weeks without any complications. No variation of the baseline clinical scenario as evidenced clinically and radiographically at the end of follow-up. No similar cases are reported in the literature.

Vertical and horizontal ridge augmentation using customized CAD/CAM titanium mesh with versus without resorbable membranes. A randomized clinical trial.

OBJECTIVES: The aim was to evaluate the role of resorbable membranes applied over customized titanium meshes related to soft tissue healing and bone regeneration after vertical/horizontal bone augmentation. MATERIALS AND METHODS: Thirty patients with partial edentulism of the maxilla/mandible, with vertical/horizontal reabsorption of the alveolar bone, and needing implant-supported restorations, were randomly divided into two groups: Group A was treated using only custom-made meshes (Mesh-) and Group B using custom-made meshes with cross-linked collagen membranes (Mesh+). Data collection included surgical/technical and healing complications, "pseudo-periosteum" thickness, bone density, planned bone volume (PBV), regenerated bone volume (RBV), regeneration rate (RR), vertical bone gain (VBG), and implant survival in regenerated areas. Statistical analysis was performed between the two study groups using a significance level of α = .05. RESULTS: Regarding the healing complications, the noninferiority analysis proved to be inconclusive, despite the better results of group Mesh+ (13%) compared to group Mesh- (33%): estimated value -1.13 CI-95% from -0.44 to 0.17. Superiority approach confirmed the absence of significant differences (p = .39). RBV was 803.27 mm3 and 843.13 mm3 , respectively, and higher RR was observed in group Mesh+ (82.3%) compared to Mesh- (74.3%), although this value did not reach a statistical significance (p = .44). All 30 patients completed the study, receiving 71 implants; 68 out of them were clinically stable and in function. CONCLUSION: The results showed that customized meshes alone do not appear to be inferior to customized meshes covered by cross-linked collagen membranes in terms of healing complication rates and regeneration rates, although superior results were observed in group Mesh+compared to group Mesh- for all variables.

Flapless and bone-preserving extraction of partially impacted mandibular third molars with dynamic navigation technology. A report of three cases.

AIM: Most of the intra- and postoperative patient discomfort related to complex mandibular third molar (M3M) extraction is proportional to the invasiveness of the surgery. This can be minimized through the support of dynamic navigation (DN) technology, which can be successfully applied in dental implantology. Materials and methods: Three patients, one female (aged 25 years) and two males (aged 18 and 51 years, respectively) underwent the DN-supported extraction of partially impacted M3Ms with a flapless approach that required minimal bone removal. The patients' discomfort and the speed of recovery were considered to be proof of the quality of the adopted procedure. RESULTS: No postoperative discomfort such as pain or swelling was recorded in the immediate postoperative period, and no complications were reported within a month of the surgery. No medications were prescribed. The procedure lasted no longer than 20 min in all cases. CONCLUSION: Using DN technology, the real-time 3D monitoring of the clinical situation in each surgical phase enabled the surgeon to avoid soft tissue detachment as well as limit bone loss and intraoperative bleeding, thanks to a precise multi--section of the tooth and important nearby anatomical structures, respectively.

Full Zirconia Implant-Born Prosthetic Rehabilitation with CAD/CAM Technology after Accurate Digital Planning. A Case Report.

CAD/CAM technology can enhance the dentistry application of ceramic materials that meet the more relevant biocompatibility and aesthetics demands. In implant-borne prosthesis rehabilitation, yttria-stabilized zirconia appeared to be a valid alternative to metal-alloys and titanium, with comparable mechanical properties and even better interaction with bone and soft tissues. The improvement of monolithic CAD/CAM manufacturing allows for a reliable, predictable, and rapid workflow that can correspond to a holistic treatment philosophy associated with zirconia fixtures. This reported clinical case highlights the advantages of this approach in resolving particularly functionally and aesthetically complex situations. A 40-year-old patient with permanent canine impaction and the persistence of a deciduous tooth compromised by caries was successfully rehabilitated with the surgical removal of the enclosed tooth, the seating of a mono-phase zirconia implant after the deciduous extraction and its loading with a zirconia single crown, without any clinical or radiographical alteration up to seven years follow-up.

Digital Approach for the Rehabilitation of the Edentulous Maxilla with Pterygoid and Standard Implants: The Static and Dynamic Computer-Aided Protocols.

A full-arch rehabilitation of the edentulous upper jaw without grafting procedures exploits the residual alveolar or the basal bone, with the necessity of long implants placed with a particular orientation. The precision in planning and placing the fixtures is fundamental to avoid clinical problems and to allow an acceptable connection with the prosthesis. The computer-aided implantology resulted in more accuracy than the traditional one, with a high standard of correspondence between the virtual project and the real outcome. This paper reports about the two different digital protocols, static and dynamic, as support to implant-borne prosthetic rehabilitation of edentulous maxillae. Two pterygoid and two/four anterior standard implants were seated in both cases by two different operators, without flap raising, and immediately loaded. This approach avoided the posterior cantilever by-passing the maxillary sinus and was adequately planned and realized without any surgical or prosthetic error. The two digital flow-charts were described step by step, underlining each other's advantages and drawbacks compared to a free-hand approach.

Dynamic Navigation for Zygomatic Implants: A Case Report about a Protocol with Intraoral Anchored Reference Tool and an Up-To-Date Review of the Available Protocols.

Dynamic Navigation is a computer-aided technology that allows the surgeon to track the grip instruments while preparing the implant site in real time based on radiological anatomy and accurate pre-operative planning. The support of this technology to the zygoma implant placement aims to reduce the risks and the errors associated with this complex surgical and prosthetic treatment. Various navigation systems are available to clinicians currently, distinguished by handling, reliability, and the associated economic and biological benefits and disadvantages. The present paper reports on the different protocols of dynamic navigations following a standard workflow in correlation with zygomatic implant supported rehabilitations and describes a case of maxillary atrophy successfully resolved with this technology. An innovative and minimally invasive dynamic navigation system, with the use of an intraoral anchored trust marker plate and a patient reference tool, has been adopted to support the accurate insertion of four zygomatic implants, which rapidly resolved maxillary atrophy from a 75-year-old male system. This approach provided an optimal implant placement accuracy reducing surgical invasiveness.

Ultrasonic Navigation for the Treatment of Medication-Related Jaw Osteonecrosis Involving the Inferior Alveolar Nerve: A Case Report and Protocol Review.

Dynamic navigation (DN) is a computer-guided technique employed in different surgical fields and recently adopted in dental implantology to improve the accuracy of dental implant insertion. Medication-related osteonecrosis of the jaws (MRONJ) often requires the surgical removal of the impaired, hard tissue, trying at the same time to spare the healthy tissue and the noble anatomical structures. A case of extensive bilateral medication-related osteonecrosis, with the symptomatic involvement of the right mandibular canal, was successfully resolved with the use of ultrasonic surgery associated with a dynamic navigation, in order to limit the invasiveness of the surgical approach improving its reliability and accuracy. The usefulness of this technology in the management of MRONJ can be considered in future clinical trials to confirm the advantages and standardize the technique.

Analysis of Marsupialization of Mandibular Cysts in Improving the Healing of Related Bone Defects.

PURPOSE: Marsupialization, designed to reduce the mandibular cyst volume, has continued to debated regarding its influence on the healing of the related bone cavity. The aim of the present study was to evaluate the 3-dimensional radiographic variation over time in mandibular odontogenic cystic lesions after marsupialization and assess the correlations between these variations and variables that can affect the procedure. MATERIALS AND METHODS: We planned a retrospective cohort study. The predictor variables were the treatment duration, preoperative volume, patient age, histologic type, and number of preoperative residual bony walls. The outcomes variables were the postoperative volume reduction and the daily reduction rate calculated using computed tomography (CT) from before to after marsupialization using software designed for volumetric reconstruction and measurement of cyst-related bone defects. The descriptive and bivariate statistics were computerized, and the significance level was set at P = .05. RESULTS: The sample included 15 patients (12 men and 3 women; mean age, 51.6; range, 27 to 85 years) affected by keratocysts (n = 6), dentigerous cysts (n = 6), and radicular cysts (n = 3) who had undergone marsupialization. The median duration of marsupialization was 406 days (25th to 75th percentile, 276 to 519). The mean ± standard deviation (SD) pre- and postdecompression volumes were 6,908.27 ± 2,669.058 and 2,468.13 ± 1,343.517 mm3, respectively (P < 0.001), and the mean ± SD percentage of reduction was 63.90 ± 13.12%. The volume decrease in the bone defects correlated positively with the treatment duration (P = .009) and preoperative volume (P < .001). However, no correlation was found with the other variables (P > .05) nor between the daily reduction rate and other variables (P > .05). CONCLUSIONS: Marsupialization appears useful in improving the healing of cyst-related bone defects in mandibles, especially larger defects. Further studies with a wider sample size would add more knowledge to this topic.

Long-term investigation of decompression as a definitive treatment for mandibular cysts associated with impacted third molars.

BACKGROUND: Clinicians sometimes use decompression for secondary, low-risk cyst enucleation. The authors explored whether the decompression of dentigerous cysts associated with third molars is a reliable, long-term, definitive treatment option. METHODS: The authors monitored 25 mandibular cysts associated with impacted third molars in adults after surgical decompression without the extraction of the related tooth for a mean (standard deviation) time of 37 (15) months (range, 12-71 months). The authors carefully evaluated the postoperative clinical situation and the extent of radiographic shrinkage. RESULTS: A minimal epithelial slit remained patent in all patients. All lacked clinical problems, had no need for further intervention, and exhibited persistent impaction of the teeth. The cyst reduction rate calculated on panoramic radiographs ranged from 63.4% to 98.8% (mean [standard deviation] 87.5% [10.6%]) and was statistically significant (P < .05). In 13 patients, the reduction rate was greater than 90%. CONCLUSIONS: Decompression triggered marked radiographic reductions of cysts when epithelial communication persisted. The situation stabilized after the first 6 through 8 months, and no further intervention was required. PRACTICAL IMPLICATIONS: It is risky to enucleate cysts associated with impacted third molars and extract the molars. Clinicians can solve the problem in dental practice by using surgical decompression.

Prosthetically CAD-CAM-Guided Bone Augmentation of Atrophic Jaws Using Customized Titanium Mesh: Preliminary Results of an Open Prospective Study.

This study evaluated the outcomes of computer-aided design-computer-aided machining (CAD-CAM)-customized titanium mesh used for prosthetically guided bone augmentation related to the occlusion-driven implant position, to the vertical bone volume gain of the mandible and maxilla, and to complications, such as mesh exposure. Nine patients scheduled for bone augmentation of atrophic sites were treated with custom titanium mesh and particulate bone grafts with autologous bone and anorganic bovine bone in a 1:1 ratio prior to implant surgery. The bone volume needed to augment was virtually projected based on implant position, width, and length, and the mesh design was programmed for the necessary retaining screws. After 6 to 8 months, bone augmentations of 1.72 to 4.1 mm (mean: 3.83 mm) for the mandibular arch and 2.14 to 6.88 mm (mean: 3.95 mm) for the maxilla were registered on cone-beam computerized tomography. Mesh premature (within 4 to 6 weeks) exposure was observed in 3 cases and delayed (after 4 to 6 weeks) in 3 other cases. One titanium mesh was removed before the programmed time but in all augmented sites was possible implant insertion. No complication occurred during prosthetic follow-up. Using CAD-CAM technology for prosthetically guided bone augmentation showed important postoperative morbidity of mesh exposure (66%). Because of this high prevalence of mesh exposure and the potential infection that could affect the expected bone augmentation, this study suggests a cautious approach to this procedure when designing the titanium mesh, to avoid flap tension that may cause mucosal rupture.

Reconstruction of Extended and Morphologically Varied Alveolar Ridge Defects with the Titanium Mesh Technique: Clinical and Dental Implants Outcomes.

A sample of 24 patients with varied morphologic defects were treated with 34 titanium meshes and particulate bone and rehabilitated at least 8 to 9 months thereafter with the placement of 88 implants. Of the 34 meshes, 4 had to be removed before implant placement (11.76% total failure) and 20 were exposed due to soft tissue dehiscence (58.82% of complications): 4 (11.77%) prematurely (within 4 to 6 weeks) and 16 (47.05%) delayed (after 4 to 6 weeks), with no compromise in implant placement. None of the 88 implants was lost (100% implant survival), and 15 demonstrated increased bone loss, yielding a cumulative implant success rate of 82.9%. This technique appears useful in treating extended and morphologically varied alveolar defects.

Titanium Mesh Technique in Rehabilitation of Totally Edentulous Atrophic Maxillae: A Retrospective Case Series.

BACKGROUND: This study evaluates implant-borne prosthetic rehabilitation of 10 totally edentulous atrophic maxillae after bone reconstruction with a titanium-mesh technique and particulate bone graft. METHODS: Ten atrophic maxillae were reconstructed with 19 titanium meshes and particulate autologous-heterologous bone. Maxillae were rehabilitated at least 5 months, with placement of 67 implants connected to the prostheses after an additional 4 months of rehabilitation. Cases were evaluated retrospectively in terms of complication rates, particularly on the amount of mesh exposure, implant survival, and success rates at the end of follow-up. RESULTS: In seven cases, two meshes were prematurely exposed (within 4 to 6 weeks), and five were exposed later (after 4 to 6 weeks). Only two of the later exposures extended >1 cm(2). Nevertheless, reconstructions allowed implant placement and prosthetic rehabilitation in all cases. Two implants were lost before loading. After mean follow-up at 39.3 (20 to 56) months since prosthetic loading, all 65 implants were functional (100% implant survival), but 15 implants demonstrated a peri-implant mean bone resorption of 2.96 mm increased bone loss, yielding a cumulative implant success rate of 76.9%. No prosthetic problem was observed. CONCLUSIONS: Use of titanium mesh with particulate bone can be considered a valid option in reconstructing atrophic maxillae to allow for implant-borne prosthetic rehabilitation. A high level of dehiscence did not compromise final outcome.

Alveolar ridge reconstruction with titanium mesh: a three-dimensional evaluation of factors affecting bone augmentation.

PURPOSE: To evaluate the three-dimensional (3D) reconstruction of atrophic alveolar ridges using titanium mesh (Ti-mesh) and its correlation with the extent and timing of mesh exposure and amount of reconstruction planned. MATERIALS AND METHODS: This study retrospectively evaluated 12 patients (mean age, 49.1 years) with 15 alveolar defects treated with Ti-mesh and particulate grafts (70/30 autogenous bone/anorganic bovine bone) followed by implant placement 8 to 9 months later. For each site, computed tomography images were analyzed using software designed to measure 3D volumes. The lacking bone volume (LBV) was calculated by subtracting the reconstructed bone volume at reentry from the planned bone volume (PBV). In all cases, the meshes were modeled preoperatively on a stereolithographic model. LBV was correlated with the extent and time of mesh exposure and PBV. RESULTS: The mean LBV (0.45 cm3) was 30.2% (range, 6% to 74%) of the mean PBV (1.49 cm3). The mean extent and timing of mesh exposure, which occurred at 80% of augmented sites (12/15), were 0.73 cm2 (range, 0.09 to 3.45 cm2) and 2.17 months (range, 1 to 8 months), respectively. LBV was significantly positively correlated with the area of mesh exposed, with 16.3% LBV for every cm2 of mesh exposed; there were positive correlations between LBV and early exposure and PBV. CONCLUSION: On average, there was 30.2% less bone than planned preoperatively; there was a significant negative correlation between the amount of reconstructed bone and area of mesh exposed.

Alveolar distraction osteogenesis in posterior atrophic mandible: a case report on a new technical approach.

PURPOSE: To report a clinical case of dental implant rehabilitation of an atrophic posterior mandible with the usage of a new alveolar distraction protocol. MATERIALS AND METHODS: A posterior atrophic mandible was treated with distraction osteogenesis; after the first phase of latency (10 days), the activation phase (24 days), and the consolidation phase (30 days), the distractor was removed, and 2 implants were placed; 4 months thereafter, the fixtures were provisionally loaded. RESULTS: No complications were recorded during the treatment. At the end of the activation phase, a mean of 5 mm of vertical bone augmentation was obtained, and it allowed the placement of two 10-mm long fixtures. No periimplant bone resorption was detected at the time of definitive prosthetic loading. CONCLUSIONS: The proposed protocol secured a sound prosthetic rehabilitation on an otherwise atrophied posterior mandible so as to avoid grafting procedures.

Magnesium-substituted hydroxyapatite grafting using the vertical inlay technique.

The reconstruction of a severely atrophic left posterior mandible using inlay magnesium-substituted hydroxyapatite grafting is described. Three months after reconstruction, a bone specimen was retrieved, and two dental implants were placed. A mean vertical bone gain of 4.9 mm was measured at the time of implant placement, and no problems were recorded at delivery of the provisional and definitive prostheses 4 and 8 months after implant placement, respectively. Histologic analysis revealed residual grafted material infiltrated by newly formed bone. In this clinical case, Mg-hydroxyapatite was demonstrated to be an effective grafting material for reconstruction of the posterior mandible using the inlay technique.