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.

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.

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.

Immediate full-arch fixed rehabilitation of a narrow mandible with newly conceived connection system implants: A case report.

Rehabilitating thin jaws without reconstructive surgery entails using narrow implants. The proposed treatment adopted an innovative implant system, allowing the mini-screws to be parallel and immediately loaded. A mandible, wearing an overdenture, was functionalized contextually to the residual dental extraction and the placement of six 2.4-mm thick one-piece implants. Low-profile intermediate abutments, the LEMs, able to rotate over the spherical heads of the fixtures, were connected after suturing, oriented, and blocked in a mutual parallel position. The copings, engaging with a tapered juncture of the LEMs, resulted in their alignment to be intraorally wedged together. The provisional superstructure enclosed the copings and was immediately connected to the implants, and the definitive prosthesis was delivered after three months. No clinical signs of peri-implantitis or radiographically evident bone loss were recorded after a two-year follow-up without any prosthetic complication. No cases have been published regarding mini-implants bearing fixed prosthesis rehabilitation.

Volume reduction of cystic lesions after surgical decompression: a computerised three-dimensional computed tomographic evaluation.

OBJECTIVES: This study was performed to evaluate the three-dimensional radiographic variation in mandibular odontogenic cystic lesions after decompression. MATERIALS AND METHODS: Pre- and post-decompression computed tomography (CT) evaluations in 20 patients affected by keratocysts (n = 10), dentigerous cysts (n = 9) and ameloblastoma (n = 1) were analysed using software designed for three-dimensional measurement of volumes; the results were correlated with treatment duration, age, sex and histological type. RESULTS: The mean (range) decompression time was 5.70 (3-12) months. The mean (SD) pre- and post-decompression volumes were 9.50 (7.74) and 4.65 (4.34) cm(3), respectively (P < 0.001), with a mean (SD) reduction of 49.86 % (19.34 %). The volume reduction was positively correlated with the duration of decompression (P < 0.001), whereas no correlations with other variables were found (P = 0.2357). The median monthly reduction in cyst volume was 11.34 % (mean, 13.52 %; range, 4.45-30.43 %) (P < 0.001). CONCLUSIONS: This three-dimensional CT investigation demonstrated the effectiveness of decompression in the treatment of mandibular odontogenic cystic lesions and showed a positive correlation between the duration of treatment and volume reduction. CLINICAL RELEVANCE: Decompression treatment, which is simple to perform and generally well-accepted by patients, is a reliable method to considerably reduce the volume of mandibular odontogenic cystic lesions before surgical removal. Extended decompression time seems to improve results of the reduction process.

Radiographic assessment of the mandibular retromolar canal using cone-beam computed tomography.

OBJECTIVE: The 'retromolar' nerve is a collateral branch of the inferior alveolar nerve. Cone-beam computed tomography (CBCT) provides higher resolution images. This CBCT study reports the frequency of the retromolar nerve. MATERIALS AND METHODS: From 2007-2010 the CBCT study of 233 hemi-mandibles have been examined. The CBCT study was obtained from an investigation of the posterior mandibular region in 187 patients suffering from different pathologies and it was aimed at detecting in patients the presence of a retromolar canal and foramen. RESULTS: Thirty-four retromolar canals with a foramen were detected on 233 CBCT (14.6%) in 30 out of 187 patients (16%). In the 46 patients who underwent CBCT bilaterally, the retromolar canal was found in nine subjects (19.6%) and was present bilaterally in four subjects, for an incidence of 8.7%. CONCLUSIONS: The results suggest that the radiological frequency of the retromolar nerve is notable, with a possible relevance in the surgical approach of the mandibular retromolar area. The presence of a retromolar canal, well detected with CBCT, may warn clinicians about the possibility of inadequate pre-surgical anaesthesia, local intra-operative bleeding and post-operative alterations of the sensation in the third molar area.

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.

Case of severe bone atrophy of the posterior maxilla rehabilitated with blocks of equine origin bone: histological results.

PURPOSE: To report the histological outcomes of a case of bilateral severely resorbed posterior maxilla augmented with the use of blocks of enzymatically deantigenated equine bone. MATERIALS AND METHODS: In conjunction with bilateral sinus lifts, blocks of enzymatically deantigenated equine bone were used bilaterally to augment the severely atrophic maxilla of a patient seeking a fixed implant-supported prosthesis. After 8 months, bone core samples were obtained from the augmentation sites and implants were placed. RESULTS: Six months after implant placement, the peri-implant bone levels were maintained. A prosthesis delivered 3 months after implant placement provided excellent rehabilitation. Histological analysis of the bone cores revealed that the graft material was still undergoing remodeling, with newly formed vital bone in all fields and osteoclasts included in the mineralized component. CONCLUSIONS: The deantigenated equine bone was biocompatible and resorbed only minimally. This material seems to offer excellent potential for being incorporated in a procedure that increases the width of edentulous alveolar crests.

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.

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.

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.

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.

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.

Le Fort I osteotomy with interpositional graft and immediate loading of delayed modified SLActive surface dental implants for rehabilitation of extremely atrophied maxilla: a case report.

PURPOSE: To describe a successful clinical case of immediate prosthetic loading of modified sandblasting and acid-etching surface ITI dental implants inserted in a grafted maxilla after Le Fort I osteotomy. MATERIALS AND METHODS: A 59-year-old man with a severely atrophied maxilla was treated with Le Fort I osteotomy and interpositional iliac bone graft. Thirteen weeks later, 7 modified sandblasted and acid-etched surface ITI dental implants were inserted with immediate application of a screw-fixed prosthetic acrylic device kept in functional loading for 3 months until a definitive fixed prosthesis was inserted. RESULTS: After 20-month follow-up there has been no implant failure, with minimal bone loss and healthy peri-implant soft tissues; the patient is functionally and esthetically satisfied. CONCLUSIONS: Immediate loading of implants placed after Le Fort I osteotomy and interpositional iliac bone grafting could be an applicable protocol to rehabilitate extremely atrophied edentulous maxillas.

Reconstruction of atrophied posterior mandible with inlay technique and mandibular ramus block graft for implant prosthetic rehabilitation.

PURPOSE: To describe a successful clinical case of implant prosthetic rehabilitation in an atrophic posterior mandible reconstructed by inlay bone grafting after bone block harvesting from the mandibular ramus. PATIENTS AND METHODS: A 55-year-old woman with an atrophied right posterior mandible underwent surgical inlay ridge augmentation under local anaesthesia using a block graft harvested from the ipsilateral mandibular ramus. Three months later 3 dental implants were inserted, and after an additional 4 months abutments were connected and a definitive fixed bridge inserted. RESULTS: After a 24-month follow-up, no implant failure was recorded; the patient was functionally and esthetically satisfied. CONCLUSION: The inlay procedure in atrophic posterior mandible, associated with mandibular ramus graft harvesting, may be considered an effective, minimally invasive and well-tolerated procedure for implant prosthetic rehabilitation.

Implant prosthetic rehabilitation of posterior mandible after tumor ablation with inferior alveolar nerve mobilization and inlay bone grafting: a case report.

PURPOSE: To report a successful clinical case of dental implant provisionalization of a posterior mandible resected for tumor ablation and subsequently reconstructed with interpositional bone grafting after mobilization of the inferior alveolar nerve. MATERIALS AND METHODS: A 47-year-old woman with a severe posterior mandibular defect due to ablation of a squamous cell carcinoma was treated with transposition of the inferior alveolar nerve and inlay iliac bone graft. Four months later, 4 dental implants were inserted and immediately provisionalized. Bone core biopsies were taken during implant insertion. After an additional 3 months, a definitive fixed bridge was inserted. RESULTS: At the 24-month follow-up visit, all implants appeared to have osseointegrated. The histologic examination showed that the grafted bone was lined by newly formed bone without gaps at the interface. CONCLUSIONS: Inlay bone grafting can allow implant provisonalization of the posterior mandible even with a remarkable bone alveolar deficit after tumor ablation.

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.