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Purpose: Dental reconstruction for patients diagnosed with severe mandibular bone atrophy using common dental implants is a challenging process. In such cases, surgeons may encounter challenges such as insufficient available bone, soft tissue, damage to the inferior alveolar nerve, and even the risk of bone fracture. In this study, a new design concept of mandibular patient-specific implants for severely atrophic ridges followed by finite element evaluation was presented to investigate the mechanical functionality of the concept. Method: The implant is comprised of two modular parts including an inferior border cover and a horseshoe-shaped structure. This horseshoe segment fits into the cover and is then screwed to it using two screws on each side. A 1 mm deflection was applied to a reference point located between the two anterior posts to extract the resulting Von Mises stress distribution in each part and the reaction force on the reference point which corresponds to the chewing force that the patient must apply to deform the horseshoe. This 1 mm gap is a design consideration and critical distance that horseshoe contacts the gingiva and disturbs the alveolar nerve. Results: The results revealed that load was transmitted from the horseshoe to the cover, and there were no stress contours on the body of the mandible. However, stress concentration was observed in screw locations in the mandible, the amount of which was decreased by increasing the number of used screws. In horseshoe, stress concentration values were around 350 MPa, and the measured reaction force on the reference point was just under 200 N. Conclusion: The finite element analysis results showed that this concept would be functional as the minimum load would be transmitted to the mandibular ridge, and since the patients diagnosed with atrophic ridge are not able to apply load to an amount near 200 N, the horseshoe would not contact the gingiva. Also, it is concluded that increasing the number of bone screw fixations would decrease the risk of long-term screw loosening.

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PURPOSE: The purpose of this study was to (a) record and evaluate the epidemiological data relevant to the fractures of the atrophic mandible in the Greek population (b) present our experience in the management of these difficult injuries and (c) compare our results to the outcomes of other similar studies and discuss the postoperative complications. METHODS: A prospective analysis of all the edentulous patients with fractures of the atrophic mandible treated at the Oral and Maxillofacial Surgery Department of K.A.T General Hospital of Athens in Greece was performed from November 2012 to December 2022. Age, gender and medical history of the patient, etiology and site of the fracture, classification of atrophy, type of surgical approach, type of osteosynthesis and postoperative complication. RESULTS: 34 patients were included in the present study and 48 fractures of the atrophic edentulous mandible were managed surgically. 22 fractures were classified as class II of atrophy, 21 fractures as class III and 5 injuries as class I. In 32 patients we used an extraoral approach and only 2 patients were treated with an intraoral access. 44 fractures were treated with a 2.0 mm locking reconstruction plate and only 4 injuries of class I atrophy were treated with mini plates. CONCLUSIONS: Clinical practice has confirmed that for these cases an extraoral approach followed by stable fixation with a 2.0 mm reconstruction locking plate can deliver excellent results. Our findings show that the routine use of primary bone grafts is not necessary and can be reserved for more complex cases.

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Study Design: PRISMA-SWiM guided systematic review. Objective: 1. Provide consistent evidence regarding the management of atrophic mandible fractures; 2. To search, evaluate and validate existing guidelines if any for the management; 3. Provide evidence regarding specific management of condylar fractures in the atrophic mandible; 4. To address the clinical applicability of bone grafts. Methods: A systematic review was conducted using the PRISMA-SWiM protocol. PROSPERO ID: CRD42021235111. Studies with adequate data on outcome, treatment methods were selected. Isolated case reports, case series, and non-human studies were excluded. Quality assessment was done using Newcastle -Ottawa scale. The level of evidence was assessed using Oxford Level of Evidence. Results: Mandibular body was the most common type of fracture. Self falls and RTA were the most common etiologies. Condylar fracture was most commonly managed conservatively with ORIF employed in few studies. For the mandible compression and non-compression osteosynthesis were used. Bone grafts were used in cases with segmental defects or cases requiring augmentation. Conclusions: There is lack of proper evidence to definitely conclude any single treatment modality. However, the consensus is towards ORIF. Reconstruction plates are preferred by many authors. However, unilateral fractures may be managed by miniplates. Bilateral fractures require more rigid fixations. Open reduction and internal fixation of condylar fracture is indicated in cases with displacement or low-level fractures.

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PURPOSE: To assess the body of evidence of short versus regular implants after bone augmentation (BA) in the atrophic posterior mandible in the context of implant treatment success outcomes. METHODS: Seven databases, two registries, and reference lists were searched for systematic reviews and meta-analysis (SR/MA), randomized controlled trials (RCTs) and longitudinal studies published in English, Spanish or German since 2012. Confidence in the SR/MA methodology was evaluated using AMSTAR-2 and the risk of bias of primary studies using Cochrane's RoB 2.0 and ROBINS-I. A random-effects meta-analysis and a meta-regression were performed for continuous and dichotomous outcomes. GRADE approach was used to assess the certainty of the evidence. RESULTS: Eighteen SRs/MAs, most of them "critically low" and "low" confidence with substantial overlap, included 14 relevant RCTs with a high risk of bias. A cohort study with moderate risk of bias was added. Quantitative synthesis of 595 implants and 281 hemiarches/patients indicates that the use of short implants (< 10 mm) compared to regular implants and BA may reduce implant failure at 1-year follow-up, and marginal bone loss (MBL) at 3-, 5-, and 8-year follow-up; is likely to reduce the risk of biological complications at 1-, 3-, 5-, and 8-year follow-up; and may be the patient's preferred alternative. There is a correlation between bone height, MBL and biological complications. CONCLUSIONS: The available evidence partially suggests that the use of short implants could decrease implant failure, MBL, and biological complications, and increase patient satisfaction. However, given the need for further RCTs and real-world evidence to fully evaluate short- and long-term outcomes, it would be prudent for clinicians to carefully consider the individual needs and circumstances of the patients before deciding whether to use short implants. Trial registration PROSPERO CRD42022333526.

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The aim of this study is to evaluate different plate systems and contribute to revealing the most appropriate treatment option for severe atrophic edentulous mandible fractures. A total of 8 different types of rigid internal fixation methods, which were a 4-hole miniplate on the crest, a 4-hole miniplate on the basis, a 6-hole miniplate on the crest, a 6-hole miniplate on the basis, two 4-hole mini plates on both the crest and basis, two 6-hole mini plates on both crest and basis, a 6-hole reconstruction plate on the crest and a 6-hole reconstruction plate on the basis, were simulated. Stress analysis on plates and screws and the displacement between fragments were evaluated using finite element analysis. The lowest von Mises stress was observed on the basis plate in Group 6. The highest von Mises stresses were measured on the screws closes to the fracture line. Values exceeding the boundary conditions were observed only in Groups 3 and 4 under molar loading. The highest compressive stresses were measured in Group 1, and the lowest compressive stresses were measured in Group 6. Under molar loading, the highest displacement was observed in Group 3, and the lowest displacement was observed in Group 6. When all groups are evaluated in terms of stress distributions and stability, a 1.5 mm thick six-hole reconstruction plate can be a reliable method in the treatment of severe atrophic edentulous mandible fractures.

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El uso de la planificación virtual ha demostrado en varios estudios una mayor predictibilidad de los resultados quirúrgicos, así como una reducción del tiempo quirúrgico y la posibilidad de comparar nuestros resultados con los esperados mediante una comparación con un TC postoperatorio. En esta nota técnica se describe cómo planificar de forma virtual la cirugía mediante tecnología 3D “in house” de fracturas en mandíbulas atróficas usando un software de uso libre. (AU)

The use of virtual planning has demonstrated in several studies greater predictability of surgical results, as well as a reduction in surgical time. In addition, we have the possibility to compare our results with the planning through a comparison with a postoperative CT. This technical note aims to describe how to plan surgery for fractures in atrophic mandibles using pre-surgical 3D technology and a free software. (AU)

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Background: Atrophic edentulous mandible is a challenging clinical condition. Studies assessing the use of ultrashort implants to support overdentures are scarce; the optimum photobiomodulation (PBM) dose for enhancing osseointegration is yet unknown. Objective: This study aimed to evaluate and compare mandibular overdentures assisted by two versus four ultrashort implants with adjunctive PBM therapy using two doses. Materials and Methods: A total of 36 implants were placed in 12 edentulous male participants and they were randomly allocated to Group I (mandibular overdentures assisted by two ultrashort implants) or Group II (by four ultrashort implants). Fully guided implant placement was performed, and then a split-mouth design was implemented. The participants received PBM by diode laser (660 nm). Dose A (3.75 J/cm2) and Dose B (7.5 J/cm2) were applied to the right and left implant (s), respectively. Implant stability, peri-implant probing depth (PIPD), and modified gingival index (MGI) were evaluated at baseline, and at 6 and 12 months after loading. Results: After 12 months, the implant stability values were significantly higher in Group II compared with Group I (P < 0.001). A significant difference was observed in between the PIPDs of both groups (Group I: 2.35 ± 0.54 mm; Group II: 1.69 ± 0.35 mm;P= 0.001). The mean MGI values were low for both groups (Group I: 0.75 ± 0.58; Group II: 0.51 ± 0.41). Conclusions: Mandibular overdentures supported by four ultrashort implants had a more favorable clinical outcome, while PBM doses A and B were comparable in all evaluated parameters. Trial Registration: ClinicalTrials.gov Identifier: NCT03540316.

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Purpose: The objective of this article is to report the case of an edentulous patient with a diagnosis of bilateral condylar fracture, who was treated using virtual planning. Methods: CAD/CAM technology was used for the design and manufacture of a Gunning splint, which was employed for open reduction of the right fracture and closed management of the left side. Results: The reduction of the right condylar fracture projected in the planning was achieved, as well as the return of the vertical dimension and the restoration of function, after 28 months of observation. Conclusion: In the case of total edentulism, the lack of occlusal guidance and bone atrophy are important variables to consider; however, tools such as CAD/CAM technology can be used to take more predictable treatment decisions and facilitate the execution of the procedures.

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Introduction: In the rehabilitation of total edentulous patients, lack of bone availability in posterior maxillary regions is common due to pneumatization of the maxillary sinus and posterior mandible due to the presence of the lower alveolar nerve. And to rehabilitate this type of patient, one of them is the use of short implants. Methods: The work aims to evaluate the success rate of treatment of short implants through a literature review. The search was carried out in august 2020 in the Pubmed (MedLine), Scopus and Embase databases, using the keywords: extra short implants, short implants, survival rate, single implant, atrophic mandible. The keywords followed the AND or OR criteria previously elaborated by the PICO question. The inclu-sion criteria were: implants with a length of 4 to 8 mm, which were single and in the posterior region of atrophic mandible and which had 5 years of follow-up. Articles were excluded from the review where the implants were splinted, had a follow-up of less than 5 years and considered short implants larger than 8 mm. Results: After the search, 4 articles were separated, which totaled an n = 172 short implants obtaining a success rate of 93.47% in 5 years. After the search, 4 articles were separated, which totaled an n = 172 short implants obtaining a success rate of 93.47% in 5 years. Conclusion: We can conclude that the use of short implants, even in single prostheses, has a high success rate, which can provide the edentulous patient with little bone bioavailability for rehabilitation.

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BACKGROUND: Oral rehabilitation of the atrophic mandible is, most of the time, a challenging procedure, especially in elderly patients with associated comorbidities. CASE PRESENTATION: This clinical report describes the rehabilitation of an extremely atrophic mandible using an overdenture supported by four splinted implants, two of which are placed in the interforaminal region and the other two bypassing the inferior alveolar nerve at the level of the antegonial notch. A passive-fit bar structure splinting the four inserted implants was designed to compensate for mandibular flexure, to reduce the amount of strain on the implants, and avoid bone resorption and prosthetic failure. The 14-month postoperative cone-beam computed tomography (CBCT) and the clinical follow-up showed the bilateral integrity of the inferior alveolar nerve and the successful restoration of the atrophic edentulous mandible with a significant improvement in the patient's quality of life. CONCLUSIONS: The applied technique depicts several benefits such as a minimally invasive approach, reduced number of surgical interventions, reduced total treatment time, reduced treatment costs, and higher psychological acceptability.

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OBJECTIVE: To present a feasible treatment method for fractures of severely atrophic mandibles in high-risk patients undergoing general anaesthesia (GA). CASE REPORT: A 77-year-old man presented with bilateral unfavourable fractures in an atrophic mandible. Pre-anaesthetic consultation revealed that the patient was at high risk for GA due to significant medical comorbid conditions of the patient, such as advanced age, chronic obstructive respiratory disease, diabetes mellitus and atherosclerosis. Thus, a modified treatment, consisting of open reduction and internal fixation using a combination of reconstruction plates and miniplates via an extraoral approach, was planned under local anaesthesia. The patient tolerated the surgical procedure well, without the need for sedation, and uneventful healing was achieved during postoperative period. CONCLUSION: Local anaesthesia may be considered as the anaesthetic technique of choice when managing atrophic mandible fractures to reduce the risk of complications and shorten the time needed for recovery, especially in elders with significant medical comorbidities.

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Over the past 17 years, the All-on-4 treatment concept has been a reliable and predictable modality to rehabilitate edentulous jaws with immediate function as full-arch prostheses. This article highlights clinically relevant data compiled by numerous All-on-4 investigators including complications and their remedies, occlusion and cantilever trends, implant size utilization, and controversial topics. We provide insights for navigating the complexities of medically diverse populations, faced by our daily practice, with a focus on patient avoidance, risk factors for implant and prosthetic failures, in hopes to minimize complications so clinicians would choose this treatment with confidence.

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Idiopathic mandibular condylar resorption is a rare condition in which the mandibular condyle of the temporomandibular joint (TMJ) becomes resorbed and thus reduces in size and volume. This leads to TMJ dysfunction that commonly requires surgical correction; however, more conservative interventions can also be utilized. We present a case of idiopathic mandibular condyle resorption in a 17-year-old female presenting with TMJ pain and clicking with mastication. A definitive diagnosis of this condition ultimately requires imaging studies, a reliable option being magnetic resonance imaging (MRI), which will reveal erosion of the mandibular condylar process (often bilaterally) with diminished mass and volume leading to the known sequelae of symptoms.

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INTRODUCTION: Posterior mandibular ridges with extreme atrophy are usually combined with superficial location of the mental nerve and inferior alveolar nerves (IAN) and with a short residual mandibular ridge. As a result, dental implants cannot be placed in conjunction with IAN transposition alone. The aim of this paper is to introduce a new treatment approach to treat those patients. PATIENTS AND METHODS: Eleven patients with 18 extreme atrophic posterior mandibular ridges characterized by superficial location of the IAN and short residual ridge had been treated during a 4-year period. The treatment approach included superior transposition of the IAN (IAN superioralization), 18 onlay bone block grafts harvested from the calvarial bone, implants placement through the block, and repositioning of the nerve under the onlay graft (IAN roofing). Patients were examined every 2-3 weeks; they received panoramic radiograph immediately after the surgery, at 4 months, at 6 months, and then once a year. Fixed prosthesis was performed after 4-5 months. RESULTS: The donor sites of the bone blocks healed very well. The increase of bone height ranged between 4 and 6 mm at the recipient sites, and 63 long implants were placed (10-13 mm). All the patients were hospitalized 1-3 days. The healing process was uneventful, and the nerve recovery lasted a maximal period of 6 months. The implant success and survival rates were 100%. All patients received fixed prosthesis. The functional outcomes were satisfactory with marked improvement in the quality of life of the patients. The follow-up period was 12-58 months. CONCLUSIONS: Superioralization of the IAN and roofing is a fast and predictable option to treat extremely atrophic posterior mandibular ridges with fixed prosthesis supported by dental implants.

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OBJECTIVES: Severe atrophied edentulous posterior mandible with inadequate bone height superior to the inferior alveolar canal may require transposition of the inferior alveolar nerve in order to insert dental implants. Mandibular fractures are considered a rare complication of this procedure. Implant-related spontaneous fractures of the mandible represent 0.2% of patients with inserted implants in an edentulous mandible. This report presents two cases of mandibular fractures that occurred 3 to 4 weeks after inferior alveolar nerve transposition, and were managed successfully by conservative nonsurgical treatments. METHOD AND MATERIALS: Overall, 132 procedures of inferior alveolar nerve transposition in 98 patients were performed over a period of 10 years with 379 dental implants inserted in one stage with the procedure. Patients were examined every 2 weeks. The inferior alveolar nerve function was evaluated with various sensory tests. Panoramic radiographs were obtained immediately, at 3 months, and at 1 year after the surgery. The patients received implant-supported fixed prostheses after 3 to 5 months. RESULTS: The healing process was uneventful in 96 patients; however, in two patients (1.5%) spontaneous fracture of the treated site was observed 3 and 4 weeks postoperatively. The fractures lines occurred at a failed implant site. Both cases were treated conservatively. CONCLUSIONS: Spontaneous fractures following inferior alveolar nerve transposition are an important but rare complication. Conservative treatment modalities might be useful and indicated in some of those cases.

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The beneficial mechanical properties provided by greater diameter or short implants increases their usage in the tilted implant concept. The aim of the present study is to compare the stress distribution of 4 different treatment models including variable implant numbers and diameters under a static loading protocol in the atrophic mandible using 3-dimensional finite element analysis. Three models included 2 tilted and 2 vertically positioned implants with different diameters, whereas 2 distally placed short implants were added to the fourth model. The von Mises stress as well as the maximum and minimum principal stress values were evaluated after applying 200 N bilateral oblique loads to the first molar teeth with the inclination of 45° to the longitudinal axis. Tilted implants were associated with higher stress values when compared with vertical implants in all models. The lowest stress values were obtained in the fourth model, including short implants. Although all stress values showed slight increases by descending implant diameters, the stress values of the model including implants with 3.3-mm diameter were within physiologic limits. All in all, an increasing number or diameter of implants may have a positive effect on implant survival. In addition, when narrow-diameter implants need to be inserted in the tilted implant concept, combination with short implants may be recommended for long-term success.

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INTRODUCTION: Treatment of condylar fractures in patients with atrophic edentulous mandibles is a peculiar field that has been little considered in the literature. The aim of the study was to assess the demographic and clinical variables as well as management and outcome of mandibular condylar fractures in edentulous patients with atrophic mandibles that were treated at several European departments of oral and maxillofacial surgery. METHODS: The data of all patients with fractures of the atrophic edentulous mandible from the involved maxillofacial surgical units across Europe between January 1, 2008, and December 31, 2017. Only patients that were diagnosed with condylar fractures of the edentulous atrophic mandible were included. RESULTS: A total of 52 patients met the inclusion criteria and were included in the study: 79% of patients reported one or more comorbidities. Thirty-four unilateral neck or subcondylar fractures, 9 bilateral neck or subcondylar condylar fractures, 7 unilateral head condylar fractures, and 2 bilateral head condylar fractures were diagnosed. No treatment was performed in 37 cases, whereas in 4 patients a closed treatment was decided, and 11 patients underwent open reduction and internal fixation. Outcome was considered to be satisfying in 48 patients, with no complications. CONCLUSIONS: The golden rule still remains that the diagnosis of a subcondylar or neck fracture in an edentulous patient should constitute an indication for open reduction and internal fixation. However, an appropriate choice of management options has to be individualized on a case by case basis, also depending on the patient consent.

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INTRODUCTION: Management of body fractures in patients with edentulous atrophic mandibles represents a challenging task due to patient's age, medical comorbidities, poor bone quality, and vascularity, as well as reduced contact area between the fracture ends. The aim of the study was to assess the demographic and clinical variables, the surgical technique, and outcomes of unilateral body fractures of the edentulous atrophic mandible managed at several European departments of oral and maxillofacial surgery. METHODS: This study is based on a systematic computer-assisted database that allowed the recording of data of all patients with fractures of the atrophic edentulous mandible from the involved maxillofacial surgical units across Europe between 2008 and 2017. The following data were recorded for each patient: gender, age, comorbidities, etiology, synchronous body injuries, degree of atrophy of the mandible according to Luhr classification, type of surgical approach and fixation, length of hospitalization, and presence and type of complications. RESULTS: A total of 43 patients were included in the study: 17 patients' mandibles were classified as class I according to Luhr, 15 as class II, and 11 as class III. All patients underwent open reduction and internal fixation by extraoral approach in 25 patients, intraoral in 15 patients, and mixed in 3 patients. A single 2.0 miniplate was used in 16 patients, followed by a single 2.4 reconstruction plate in 13 patients, by two 2.0 miniplates, and three 2.0 miniplates. Outcome was considered to be satisfying in 30 patients, with no complications. Complications were observed in 13 cases. CONCLUSIONS: Treatment of unilateral body fractures of the edentulous mandible must still be based on the type of fracture, degree of atrophy, experience of the surgeon, and patients' preference. An adequate stability can be obtained by different plating techniques that have to be appropriately tailored to every single specific patient.

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OBJECTIVES: The aim of the present retrospective study was to assess the long-term clinical outcome of sandwich osteotomy in pre-implant augmentation of atrophic mandible. MATERIALS AND METHODS: Sandwich osteotomies were performed in partially and fully edentulous mandibles of 63 consecutive patients in the present study. The vertical bone gain, graft stability, and marginal bone loss were measured radiographically. Implant survival and success rates were estimated in the follow-up ranged from 2 to 144 months (mean, 58 months). RESULTS: A total of 75 procedures were reviewed. After an average healing time of 148 days, 220 implants were placed in 74 procedures. Perioperative complications included intraoperative fracture (1/75), transient paresthesia (18/75), wound healing disturbance (18/75), and keratinized tissue deficiency (14/75). The average vertical bone gain was 5.4 mm at the time of implant placement. Significant marginal bone loss occurred during the first 6 months, after which the resorption remained stable. The implant survival rate was estimated as 96.7%, and the success rate was 95.3%. Implant survival and success showed no significant correlation with higher age, anticoagulation therapy, cardiovascular disease, or thyroid disorder. Smoking was correlated with significant lower success rate. CONCLUSION: Sandwich osteotomy is a suitable augmentation procedure for atrophic mandible, allowing for implant placement with promising outcome.

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