Giuseppe Lizio

Alveolar distraction osteogenesis versus inlay bone grafting in posterior mandibular atrophy: a prospective study

OBJECTIVE The objective of this study was to compare bone gain, implant survival, implant success, bone resorption, and complication rate in groups of patients who underwent distraction osteogenesis (DO) and inlay bone grafting (Inlay) for preprosthetic issues in the atrophic posterior mandible. STUDY DESIGN Twelve surgical sites were randomly assigned to 2 treatment groups: group A: DO and group B: Inlay. After 3 to 4 months, 16 fixtures in the DO group and 21 in the Inlay group were placed for fixed prosthetic rehabilitation. The median follow-up was 26 months. RESULTS The median bone gain was 10 versus 5.8 mm (DO versus Inlay, P = .003); the median bone resorption was 1.4 mm versus 0.9 mm (DO versus Inlay, P = .088). The implant survival rate was 100% for each group, while the implant success rate was 93.7% (DO) versus 95.2% (Inlay) (P > .05). The complication rate was 60% for DO and 14.3% for Inlay (P < .05). CONCLUSION DO obtained more vertical bone gain than Inlay, but was more prone to complications in the pre-implantology phase. The implant results in each group were comparable to those in native alveolar bone.

Inlay versus Onlay Iliac Bone Grafting in Atrophic Posterior Mandible: A Prospective Controlled Clinical Trial for the Comparison of Two Techniques

PURPOSE To compare the efficacy of inlay and onlay bone grafting techniques in terms of vertical bone formation and implant outcomes for correcting atrophic posterior mandibles. MATERIALS AND METHODS Twenty surgical sites were assigned to two treatment groups, inlay and onlay, with iliac crest as donor site. After 3 to 4 months, 43 implants were placed and loaded 4 months later. The median follow up after loading was 18 months. RESULTS For the inlay versus onlay group, median bone gain was 4.9 versus 6.5 mm (p = .019), median bone resorption was 0.5 versus 2.75 mm (p < .001), and median final vertical augmentation was 4.1 versus 4 mm (p = .190). The implant survival rate was 100% in both groups, while the implant success rate was 90% versus 86.9% (p = .190, not significant). A minor and major complication rate of 20% and 10%, respectively, for both groups was encountered. CONCLUSIONS Inlay results in less bone resorption and more predictable outcomes, but requires an experienced surgeon. In contrast, onlay results in greater bone resorption and requires a bone block graft oversized in height, but involves a shorter learning curve. Once implant placement has been carried out, the outcomes are similar for both procedures.

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.

Problems with dental implants that were placed on vertically distracted fibular free flaps after resection: A report of six cases

We report the clinical outcome of dental implants placed on vertically distracted fibular free flaps that were used to reconstruct maxillary and mandibular defects after resection. Distraction osteogenesis (DO) of fibular free flaps was used for six patients (5 men, 1 woman) a mean of 19 months (range 11-38) after 5 mandibular and 1 maxillary reconstructions. A mean of 5 months (range 2-11) after removal of the distractor, 35 implants were inserted and loaded with implant-supported fixed prostheses. The mean (range) follow-up period was 39 (17-81) months. The course of the DO and the clinical and radiographic outcomes of the implants were assessed. Of six vertically distracted fibular free flaps, there was one case of vector lingual tipping during the consolidation phase and a fracture of the basal fibular cortex that necessitated additional grafting with iliac bone to stabilise the distracted area. The mean (range) vertical bone gain was 14 (12-15) mm. Four of 35 implants (11%) failed during the follow-up period. The mean peri-implant bone resorption was 2.5mm. Cumulative implant survival was 31/35 (89%) and survival after loading 31/33 (94%). Distraction osteogenesis of fibular free flaps caused a remarkable number of complications and pronounced resorption of bone around the implants, probably as a result of the formation of granulomatous tissue; a careful peri-implant follow-up and the maintenance of oral hygiene are essential.

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

Abstract 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.

Treatment of intrabony defects after impacted mandibular third molar removal with bioabsorbable and non-resorbable membranes.

BACKGROUND Mandibular second molar (M2) periodontal defects after third molar (M3) removal in high-risk patients are a clinical dilemma for clinicians. This study compares the healing of periodontal intrabony defects at distal surfaces of mandibular M2s using bioabsorbable and non-resorbable membranes. METHODS Eleven patients with bilateral probing depths (PDs) ≥6 mm distal to mandibular M2s and intrabony defects ≥3 mm, related to the total impaction of M3s, were treated with M3 extraction and covering of the surgical bone defect with a bioabsorbable collagen barrier on one side and a non-resorbable expanded polytetrafluoroethylene (ePTFE) barrier contralaterally. The PD, clinical attachment level (CAL), M2 mobility, and furcation class probing were evaluated preoperatively and 3, 6, and 9 months postoperatively. Intraoral periapical radiographs were taken immediately preoperatively and 3 and 9 months postoperatively. RESULTS Both treatment modalities were successful. At 9 months, the mean PD reduction was 5.2 ± 3.9 mm for bioabsorbable sites and 5.5 ± 3.0 mm for non-resorbable sites; the CAL gain was 5.9 ± 3.3 mm and 5.5 ± 3.4 mm, respectively. The outcome difference between the two sites for PD and CAL did not differ statistically (P >0.05) at any assessment time. CONCLUSION Bioabsorbable collagen membranes in guided tissue regeneration treatment of intrabony defects distal to the mandibular M2 obtained the same marked PD reductions and CAL gains as non-resorbable ePTFE membranes after M3 extraction.

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.

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.

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.

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.