Statements and Recommendations for Guided Bone Regeneration: Consensus Report of the Guided Bone Regeneration Symposium Held in Bologna, October 15 to 16, 2016.

INTRODUCTION: In the past 10 years, long-term studies have demonstrated that guided bone regeneration (GBR) is a successful and reliable technique for vertical and horizontal ridge augmentation, but strict and rigorous protocols must be adopted. MATERIAL AND METHODS: Because no reports have yet been published with statements and clinical recommendations for GBR, a closed meeting of all authors was organized to discuss this matter during a GBR symposium held in Bologna (Italy) in October 2016. The authors focused on the findings of systematic and narrative reviews, prepared before the meeting, covering aspects of the clinical management of GBR techniques. Successively, a discussion based on the scientific evidence and on the experts' opinions led to the formulation of statements, clinical recommendations, and implications for future research. RESULTS: To avoid complications and to optimize outcomes, the following factors should be considered by clinicians: patient selection; analysis of defect type; blood supply; antibiotic treatment; flap passivation; delayed implant placement; combination of autogenous bone and xenograft or allograft; rigorous fixation of membranes; removal after 6 to 9 months; analysis of complications; soft-tissue management; and high care in scarred sites and in esthetic areas. CONCLUSIONS: The present consensus report reviewed the scientific evidence and provided specific guidelines and recommendations for clinical practice and the different approaches to GBR techniques to ensure surgical success and predictable outcomes.

Safe New Approach to the Lingual Flap Management in Mandibular Augmentation Procedures: The Digitoclastic Technique.

PURPOSE: This article describes the digitoclastic technique, an innovative procedure for coronal displacement of the lingual flap. The new technique has the potential to obtain primary flap closure without surgical risks to the anatomical structures on the lingual side of the mandible. MATERIALS AND METHODS: Reconstruction of an atrophic mandible with guided tissue regeneration (guided bone regeneration) and implant placement is described, using the digitoclastic technique to displace the lingual flap coronally. RESULTS: Coronal flap displacement was sufficient to obtain complete passive coverage of the grafted area. No bleeding or neurosensory complications were recorded, and no membrane exposure occurred. CONCLUSIONS: The digitoclastic technique reduces the risk of damage to the lingual nerve and minimizes the amount of bleeding during surgery, allowing progressive and controlled retraction of the flap until the desired detachment is achieved.

Guided "sandwich" technique: a novel surgical approach for safe osteotomies in the treatment of vertical bone defects in the posterior atrophic mandible: a case report.

PURPOSE: A novel technique to perform safe osteotomies during inlay block regenerative procedures in the posterior atrophic mandible is described. MATERIAL AND METHODS: A 52-year-old male patient with vertical atrophy of the left posterior mandible was treated adopting an inlay block "sandwich" technique using an allogenic cancelous block and a mixture of mineralized and demineralized human bone allograft in putty form as graft. The horizontal osteotomy for the lifting of the osteotomized bone segment was performed using a template prepared from a virtual anatomical replica of the patient's mandible obtained from cone beam computed tomography data. In the second surgical phase, 3 months after the augmentation, 2 implants were easily placed. RESULTS: The horizontal osteotomy was carried out, with no risk, very close to the nerve structures after the precise osteotomy line established preoperatively on the three-dimensional computed tomography (3D-CT) virtual reconstruction. No neurological complications were observed in the first days after the procedure, and no subsequent problems were recorded during the 3-month healing period. CONCLUSION: Radiographic evaluations and complication-free clinical healing demonstrate the effectiveness of this technique to obtain safe and precise osteotomies.

The modified "sandwich" technique: a novel surgical approach to regenerative treatment of horizontal bone defects in the posterior atrophic mandible. A case report.

PURPOSE: A new augmentation procedure for bone reconstruction of horizontal defects in a posterior atrophic mandible is described. MATERIALS AND METHODS: A 47-year-old male patient with horizontal atrophy of the left posterior mandible was treated using a 2-stage modified "sandwich" osteotomy technique with an interposed mixture of mineralized and demineralized human bone allograft in putty form. RESULTS: The osteotomized superior segment was slightly raised and then drawn and rotated in the buccal direction to augment the horizontal width of the crest. The osteotomized segment was kept in this position with a titanium miniplate and miniscrews. No complications were reported during the 3-month healing period. In the second surgical phase, 2 implants were correctly placed. CONCLUSIONS: Cone beam computed tomography (CBCT) outcomes confirm the effectiveness of this technique in the treatment of horizontal defects. However, further randomized controlled studies are required to confirm the technique's reliability.

Indications for implant-supported rehabilitation of the posterior atrophic maxilla: A multidisciplinary consensus among experts in the field utilising the modified Delphi method.

PURPOSE: To establish consensus-driven guidelines that could support the clinical decision-making process for implant-supported rehabilitation of the posterior atrophic maxilla and ultimately improve long-term treatment outcomes and patient satisfaction. MATERIALS AND METHODS: A total of 33 participants were enrolled (18 active members of the Italian Academy of Osseointegration and 15 international experts). Based on the available evidence, the development group discussed and proposed an initial list of 20 statements, which were later evalu-ated by all participants. After the forms were completed, the responses were sent for blinded ana-lysis. In most cases, when a consensus was not reached, the statements were rephrased and sent to the participants for another round of evaluation. Three rounds were planned. RESULTS: After the first round of voting, participants came close to reaching a consensus on six statements, but no consensus was achieved for the other fourteen. Following this, nineteen statements were rephrased and sent to participants again for the second round of voting, after which a consensus was reached for six statements and almost reached for three statements, but no consensus was achieved for the other ten. All 13 statements upon which no consensus was reached were rephrased and included in the third round. After this round, a consensus was achieved for an additional nine statements and almost achieved for three statements, but no consensus was reached for the remaining statement. CONCLUSION: This Delphi consensus highlights the importance of accurate preoperative planning, taking into consideration the maxillomandibular relationship to meet the functional and aesthetic requirements of the final restoration. Emphasis is placed on the role played by the sinus bony walls and floor in providing essential elements for bone formation, and on evaluation of bucco-palatal sinus width for choosing between lateral and transcrestal sinus floor elevation. Tilted and trans-sinus implants are considered viable options, whereas caution is advised when placing pterygoid implants. Zygomatic implants are seen as a potential option in specific cases, such as for completely edentulous elderly or oncological patients, for whom conventional alternatives are unsuitable.

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.

The Curved Presplitting Technique in a Totally Edentulous Atrophic Mandible: A Surgical Case Report.

The management of horizontally fully edentulous atrophic ridges is a common problem in dental implantology. This case report describes an alternative modified two-stage presplitting technique. The patient was referred for an implant-supported rehabilitation of their edentulous mandible. CBCT scans showed a mean available bone width of about 3 mm. At the first stage, four linear corticotomies were performed using a piezoelectric surgical device. At the second surgical stage 4 weeks later, bone expansion was performed, and four implants were placed in the interforaminal area. The healing process was uneventful. No fractures of the buccal wall and no neurologic lesions were observed. Postoperative CBCT scans showed a mean bone width gain of about 3.7 mm. Implants were uncovered 6 months after the second surgery, and 1 month later, a fixed provisional screw-retained prosthesis was delivered. This approach could be used as a reconstructive technique that avoids using grafts and reduces treatment times, possible complications, postsurgical morbidity, and costs by exploiting the patient's native bone as much as possible. Considering the limitations of a case report, randomized controlled clinical trials are needed to confirm the results and validate this technique.

Influence of Keratinized Tissue on Short Dental Implants: A Parallel Cohort Retrospective Study on 217 Implants with a Mean Follow-up of 4.1 Years.

PURPOSE: To assess whether the presence or absence of keratinized tissue height (KTh) may have an influence on marginal bone levels, complications, and implant survival for short implants. MATERIALS AND METHODS: The study was designed as parallel cohort retrospective research. Short implants with an implant length < 7 mm were considered. One cohort was composed of patients with short implants surrounded by ≥ 2 mm of KTh (adequate KTh); the other cohort included implants with < 2 mm of KTh (not-adequate KTh). Outcome measures were marginal bone level (MBL) changes, failures, and complications. RESULTS: One hundred ten patients treated with 217 short and extrashort implants (4 to 6.6 mm long) were retrospectively included. The mean follow-up was 4.1 years after prosthetic loading (range: 1 to 8 years). The differences between KTh groups in MBL were not statistically significant at every follow-up considered: 0.05 mm at 1 year (P = .48), 0.06 mm at 3 years (P = .34), 0.04 mm at 5 years (P = .64), and 0.03 at 8 years (P = .82). A total of nine complications were reported: three in the not-adequate KTh group and six in the adequate group; the difference was not statistically significant (OR: 3.03, 95% CI: 0.68 to 13.46, P = .14). Five implants failed due to peri-implantitis, two in the not-adequate KTh group and three in the adequate group, without a statistically significant difference (OR: 2.76, 95% CI: 0.42-17.99, P = .29). CONCLUSION: This study showed no statistically significant differences in MBL, complications, and implant failure rates between short implants with adequate or not-adequate KThs. However, given the importance of patient comfort while brushing and plaque accumulation, keratinized tissue grafts could be important in selected patients, especially for those who are severely atrophic, also taking into consideration all the limitations of this study and the mediumterm follow-up. Nevertheless, longer follow-ups, larger numbers of patients, and randomized controlled clinical trials are needed before making more reliable clinical recommendations. Int J Oral Maxillofac Implants 2023;38:462-467. doi: 10.11607/jomi.9918.

Extra-short (4-mm) implants placed after regenerative failures in the posterior atrophic mandible: A retrospective study.

PURPOSE: To explore whether extra-short (4-mm) implants could be used to rehabilitate sites where regenerative procedures had failed in order to avoid additional bone grafting. MATERIALS AND METHODS: A retrospective study was conducted among patients who had received extra-short implants after failed regenerative procedures in the posterior atrophic mandible. The research outcomes were complications, implant failure and peri-implant marginal bone loss. RESULTS: The study population was composed of 35 patients with 103 extra-short implants placed after the failure of different reconstructive approaches. The mean follow-up duration was 41.3 ± 21.4 months post-loading. Two implants failed, leading to a failure rate of 1.94% (95% confidence interval 0.24%-6.84%) and an implant survival rate of 98.06%. The mean amount of marginal bone loss at 5 years post-loading was 0.32 ± 0.32 mm. It was significantly lower in extra-short implants placed in regenerative sites that had previously received a loaded long implant (P = 0.004). Failure of guided bone regeneration before placement of short implants tended to lead to the highest annual rate of marginal bone loss (P = 0.089). The overall rate of biological and prosthetic complications was 6.79% (95% confidence interval 1.94%-11.70%) and 3.88% (95% confidence interval 1.07%-9.65%), respectively. The success rate was 86.4% (95% confidence interval 65.10%-97.10%) after 5 years of loading. CONCLUSIONS: Within the limitations of this study, extra-short implants seem to be a good clinical option to manage reconstructive surgical failures, reducing surgical invasiveness and rehabilitation time.

Total mandible and bilateral TMJ reconstruction combining a customized jaw implant with a free fibular flap: a case report and literature review.

BACKGROUND: The need for whole mandibular bone reconstruction and bilateral joint replacement is fortunately rare, but it is an extremely challenging topic in maxillofacial surgery, due to its functional implications. CAD-CAM techniques development has opened new broad horizons in the surgical planning of complex maxillofacial reconstructions, in terms of accuracy, predictability, and functional cosmetic results. The review of the literature has revealed a small number of scientific reports on total mandibulectomy including the condyles, with only eleven cases from 1980. Most of the works describe reconstructions secondary to dysplastic or inflammatory diseases affecting the lower jaw. The aim of this work, reporting a rare case of massive fibrous dysplasia of the whole mandible, is to share our experience in the management of extended mandibular and bilateral joint reconstruction, using porous titanium patient-specific implants. CASE PRESENTATION: The authors present a 20-year-old male patient suffering from massive bone fibrous dysplasia of the mandible. The mandibular body and both the rami and the condylar processes had been involved, causing severe functional impairment, tooth loss, and facial deformation. The young patient, after repeated ineffective conservative surgical treatments, has required a biarticular mandibular replacement. Using virtual surgical planning (VSP) software, the authors, in collaboration with medical engineers, have created a custom-made original titanium porous mandibular implant, suspended from a bilateral artificial temporomandibular joint. The mandibular titanium implant body has been specifically designed to support soft tissues and to fix, in the alveolar region, a free fibular bone graft, for delayed dental implant prosthetic rehabilitation. CONCLUSION: The surgical and technical details, as well as the new trends in mandibular reconstructions using porous titanium implants, are reported, and discussed, reviewing literature reports on this topic. Satisfactory functional and cosmetic restorative results have been obtained, and no major complications have occurred. The patient, currently in the 18th month clinical and radiological follow-up, has recently completed the functional restoration program by an implant-supported full-arch dental prosthesis.

Semi-occlusive CAD/CAM titanium mesh for guided bone regeneration: Preliminary clinical and histological results.

PURPOSE: Guided bone regeneration is a widely used technique for the treatment of atrophic arches. A broad range of devices have been employed to achieve bone regeneration. The present study aimed to investigate the clinical and histological findings for a new titanium CAD/CAM device for guided bone regeneration, namely semi-occlusive titanium mesh. MATERIALS AND METHODS: Nine partially edentulous patients with vertical and/or horizontal bone defects underwent a guided bone regeneration procedure to enable implant placement. The device used as a barrier was a semi-occlusive CAD/CAM titanium mesh with a laser sintered microperforated scaffold with a pore size of 0.3 mm, grafted with autogenous and xenogeneic bone in a ratio of 80:20. Eight months after guided bone regeneration, surgical and healing complications were evaluated and histological analyses of the regenerated bone were performed. RESULTS: A total of 9 patients with 11 treated sites were enrolled. Two healing complications were recorded: one late exposure of the device and one early infection (18.18%). At 8 months, well-structured new regenerated trabecular bone with marrow spaces was mostly present. The percentage of newly formed bone was 30.37% ± 4.64%, that of marrow spaces was 56.43% ± 4.62%, that of residual xenogeneic material was 12.16% ± 0.49% and that of residual autogenous bone chips was 1.02% ± 0.14%. CONCLUSION: Within the limitations of the present study, the results show that semi-occlusive titanium mesh could be used for vertical and horizontal ridge augmentation. Nevertheless, further follow-ups and clinical and histological studies are required.

A new method for oral cancer biomarkers detection with a non-invasive cyto-salivary sampling and rapid-highly sensitive ELISA immunoassay: a pilot study in humans.

Introduction: Oral squamous cell carcinoma (OSCC) accounts for approximately 90% of oral malignancies and has a 5-year mortality rate close to 50%. A consistent part (70%) of all oral cancers is diagnosed at an advanced stage since available screening techniques are ineffective. Therefore, it would be urgent to improve them. The diagnostic gold standard is tissue biopsy with histological and immunohistochemical assessment. This method presents some limitations. Biopsy is invasive and the histopathological evaluation is semi-quantitative, and the absolute abundance of the target cannot be reliably determined. In addition, tissue is highly processed and may lead to loss of information of the natural state. The search for classical and new clinical biomarkers on fragments of tissue/cells collected with a cytobrush is a highly hopeful technique for early detection and diagnosis of OSCC, because of its non-invasive sampling and easy collection method. Methods: Here we analyzed cytobrush biopsies samples collected from the oral cavity of 15 patients with already diagnosed OSCC by applying an innovative high-sensitivity ELISA technique, in order to verify if this approach may provide useful information for detection, diagnosis, and prognosis of OSCC. To this end, we selected six biomarkers, already used in clinical practice for the diagnosis of OSCC (EGFR, Ki67, p53) or selected based on recent scientific and clinical data which indicate their presence or over-expression in cells undergoing transformation and their role as possible molecular targets in immunecheckpoints blockade therapies (PD-L1, HLA-E, B7-H6). Results: The selected tumor biomarkers were highly expressed in the tumor core, while were virtually negative in healthy tissue collected from the same patients. These differences were highly statistically significant and consistent with those obtained using the gold standard test clearly indicating that the proposed approach, i.e. analysis of biomarkers by a custom ELISA technique, is strongly reliable. Discussion: These preliminary data suggest that this non-invasive rapid phenotyping technique could be useful as a screening tool for phenotyping oral lesions and support clinical practice by precise indications on the characteristics of the lesion, also with a view to the application of new anti-tumor treatments, such as immunotherapy, aimed at OSCC patients.

Vertical ridge augmentation of the atrophic posterior mandible with a 2-stage inlay technique: a case report.

The use of a 2-stage inlay technique in atrophic posterior mandibles with more than 10-mm thickness and less than 5-mm height above the inferior alveolar nerve is described. The first surgical procedure was a basic corticotomy of the buccal and lingual bone. One month later, a complete inlay procedure was performed. Computed tomography and conventional radiography showed a mean vertical bone gain of 11.5 mm. This 2-stage inlay technique avoids the use of chisels to complete bone osteotomy and reduces postsurgical nerve disturbances in atrophic posterior mandibles. This technique reduces intraprocedure and postoperative patient discomfort.

Simultaneous GBR and Implant Placement with Resorbable Membranes in the Rehabilitation of Partially Edentulous and Horizontally Atrophic Dental Arches: A Retrospective Study on 97 Implants with a 3- to 7-Year Follow-up.

This retrospective study evaluates the clinical and radiographic outcomes of simultaneous guided bone regeneration (GBR) and implant placement procedures in the rehabilitation of partially edentulous and horizontally atrophic dental arches using resorbable membranes. A total of 49 patients were included, and 97 implants were placed. Patients were followed up for 3 to 7 years after loading. The data indicate that GBR with simultaneous implant placement and resorbable membranes can be a good clinical choice, and the data suggest that it could be better to horizontally reconstruct no more than 3 mm of bone in order to reduce the number of complications and to obtain stable results. However, this technique remains difficult and requires expert surgeons.

Guided implant surgery and sinus lift in severely resorbed maxillae: A retrospective clinical study with up to 10 years of follow-up.

OBJECTIVES: In the posterior maxilla, due to the presence of maxillary sinus, residual bone height lower than 3mm is a critical factor that can affect implant stability and survival. The use of guided surgery may facilitate the surgical procedures and the implant insertion in case of severely resorbed maxillae. Moreover, it may have beneficial effects on the long-term survival and success of implant-supported restorations. This study aimed to evaluate implant supported restorations on severely resorbed maxilla (<3 mm) after sinus lift with collagenated xenograft and guided surgery. METHODS: Forty-three patients with need for implant rehabilitation and residual bone height between 1 and 3 mm were recruited. Surgical and prosthetical aspects were planned following digital approach with the use of Realguide 5.0 (3diemme, Varese, Italy). Lateral window sinus lift was performed and implants were placed simultaneously to the augmentation procedure with a tooth-supported pilot drill surgical template. A pre-hydrated collagenated porcine bone matrix was adopted as regenerative material. Computer-aided-design/computer-aided-manufacturing (CAD/CAM) restorations were delivered after six months of healing. Milled titanium chamfer abutments with CAD/CAM crowns were used. Bone height at implant site level was measured using an image software analysis applied to the pre- and post-surgical radiographs and at the follow-up. Biological and technical complications were recorded during all the follow-up periods. RESULTS: Fifty-four sinus were treated. After a mean follow-up time of 5.11 years (SD: 2.47), no implants were lost nor showed signs of disease. The mean pristine bone height was 2.07 mm (SD: 075). At the final evaluation the augmented sinus height was 12.83 mm (SD: 1.23). Two cases experienced minor perforation of the membrane, while five patients developed minimal post-operative complications, completely resolved with pharmacologic therapy. No mid-term biological complications were experienced by the patients. No cases experienced peri-implant mucositis and peri-implantitis during the whole follow-up period. Four patients (7.4%) faced an unscrewing of the prosthesis. CONCLUSIONS: The present study showed the efficacy in the mid-term of the digital planning and the guided surgery in restoring severely resorbed posterior maxilla with dental implants. CLINICAL SIGNIFICANCE: This paper underlines the high potential of the digital approach in the mid-term to implant rehabilitation of severely resorbed maxilla simultaneously with sinus lift.

A 5-year randomized controlled clinical trial comparing 4-mm ultrashort to longer implants placed in regenerated bone in the posterior atrophic jaw.

BACKGROUND: Short implants (up to 5-mm long) have shown good results when compared to longer implants placed in augmented bone. PURPOSE: To evaluate if 4-mm ultrashort implants could also be an alternative to bone augmentation in the severely atrophic posterior jaws. The primary aim of the study was to compare implant survival rates between study groups. MATERIALS AND METHODS: Eighty partially edentulous patients with posterior atrophic jaws (5-6 mm of bone above the mandibular canal and 4-5 mm below the maxillary sinus) were included: 40 patients in the maxilla and 40 in mandible. The patients were randomized to receive one to three 4-mm ultrashort implants or one to three implants at least 10-mm long in augmented bone. Results are reported 5 years after loading with the following outcome measures: implant and prosthetic failures, complications and peri-implant marginal bone level changes. RESULTS: Thirty-two complications were reported for the control group in 18 patients versus 13 complications in 10 patients in the test group, the difference being not statistically significant (p = 0.103). In the augmented group, 12 implants failed in 6 patients versus 7 short implants in 6 cases, and 9 prostheses failed in the control group while 4 in the test one, without statistically significant differences (p = 1.000 and 0.363, respectively). At 5 years after loading, short implants lost on average 0.58 ± 0.40 mm of peri-implant marginal bone and long implants 0.99 ± 0.58 mm, the difference was statistically significant (p = 0.006). CONCLUSION: Four-millimeter ultrashort implants showed similar if not better results when compared to longer implants placed in augmented jaws 5 years after loading. For this reason, their use could be in specific cases preferable to bone augmentation since the treatment is less invasive, faster, cheaper and associated with less morbidity. However, longer follow-ups and larger trials are needed.

Radiographic protrusion of dental implants in the maxillary sinus and nasal fossae: A multidisciplinary consensus utilising the modified Delphi method.

The aim of the present study was to generate an international and multidisciplinary consensus on the clinical management of implant protrusion into the maxillary sinuses and nasal fossae. A total of 31 experts participated, 23 of whom were experts in implantology (periodontologists, maxillofacial surgeons and implantologists), 6 were otolaryngologists and 2 were radiologists. All the participants were informed of the current scientific knowledge on the topic based on a systematic search of the literature. A list of statements was created and divided into three surveys: one for all participants, one for implant providers and radiologists and one for otolaryngologists and radiologists. A consensus was reached on 15 out of 17 statements. According to the participants, osseointegrated implants protruding radiographically into the maxillary sinus or nasal fossae require as much monitoring and maintenance as implants fully covered by bone. In the event of symptoms of sinusitis, collaboration between implant providers and otolaryngologists is required. Implant removal should be considered only after pharmacological and surgical management of sinusitis have failed.

Reconstruction of atrophied anterior mandible with an inlay technique and resorbable miniplates: a case report.

This case report describes an inlay augmentation procedure with resorbable bone plates and fixation screws in a case of vertical atrophy of the anterior mandible. After 3 months from the surgery, vertical bone height augmentation was evaluated, and at the time of implant insertion, core biopsies from the grafted area were taken. Moreover, 8 months after the start of prosthetic loading, radiographic assessments showed no pathological signs. This case report shows that the effectiveness of resorbable plates during the graft healing process is similar to that of titanium plates.

An Ancient Science to Improve Today's Clinical Practice: Oral Surgery Meets Human Anatomy.

Human body dissection was a ubiquitous practice in the past, to better understand anatomy and to develop medicine. Today, its role could still be important to answer everyday clinical queries and help surgeons. The example of the possible lack of anesthesia during symphysis surgeries can emphasize the usefulness of dissection. The mandibular symphysis usually receives innervation from inferior alveolar nerve terminations, but, in some rare cases, a particular anastomosis involves the lingual nerve and the nerve to the mylohyoid. The anatomical knowledge resulting from body dissections could help oral surgeons to understand the reason why the patient could feel pain during the surgery, and ensure performance of the right lingual nerve block to obtain complete anesthesia. This clinical situation shows the educational role of an ancient, yet still valid, practice, human dissection, and the importance of anatomical studies to improve surgical skills, to provide better treatment for the patient.

Decision Criteria Proposed for the Treatment of Vertical Bone Atrophies in the Posterior Mandible.

In everyday practice, surgeons have to deal with bone atrophy. These rehabilitations are even more complex in the posterior mandible, and it is still unclear in the literature which fixed rehabilitation option is best. The purpose of this article was to help oral surgeons to choose the proper and updated treatment for their atrophic patients. Posterior mandible bone atrophies were divided into four main groups depending on the bone height measured above the inferior alveolar nerve: (1) ≤ 4 mm; (2) > 4 mm ≤ 5 mm; (3) > 5 mm ≤ 6 mm; (4) > 6 mm < 7 mm. Different approaches were proposed for each group, considering patient expectations. If ≤ 4 mm of bone height was available, guided bone regeneration was used as the adequate approach. For bone heights > 4 mm and ≤ 6 mm, the "sandwich" technique and/or short implants were used, depending on esthetics. In cases with > 6 mm and < 7 mm above the mandibular canal, short implants might be the proper option. The authors' clinical experience and the literature were considered in order to suggest a possible correct treatment decision based on the residual bone height in the posterior mandible.