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Purpose: To demonstrate a modified surgical approach for horizontal ridge augmentation that allows for safe manipulation and predictable management of the buccal plate and avoids creation of a secondary surgical site. Materials and Methods: This pilot randomized controlled clinical trial included 24 patients who required horizontal alveolar ridge augmentation. Patients were assigned to one of the three groups: Group A was treated with the buccal plate repositioning (BPR) technique and grafted with silica calcium phosphate nanocomposite (SCPC) graft, group B was similarly managed and grafted using demineralized freeze-dried bone allograft (DFDBA), and group C was augmented using mandibular ramus autogenous bone block graft (ABBG). The primary outcome was the coronal crest width, which was measured at 6 months using CBCT. Results: The BPR technique resulted in horizontal augmentation with a mean of 4.30 ± 0.94 mm for group A, showing no significant difference from either group B (4.98 ± 1.13 mm) or group C (3.68 ± 0.27 mm). All augmented ridges allowed for successful implant placement with good primary stability. Conclusions: The BPR technique resulted in horizontal bone gain in extremely narrow alveolar ridges. It allowed for implant placement in a vascular cancellous bed protected by intact cortical plate. Different types of bone grafts, whether alloplast or allograft, resulted in successful augmentation comparable to that gained from autogenous block grafting. [ABSTRACT FROM AUTHOR]

Abstract Background Trans- inferior alveolar nerve (IAN) implantation technique was wildly used while the potential appropriate angle range in which the residual alveolar bone can bear the stress without absorption are currently unclear. This study aimed to evaluate the stress distribution pattern of the interface between bone and implant by finite element analysis (FEA) to determine the appropriate range of the implant tilt angle. Methods Cone beam computed tomography (CBCT) images of 120 patients with missing mandibular second molars and vertical bone height

Background: Trans- inferior alveolar nerve (IAN) implantation technique was wildly used while the potential appropriate angle range in which the residual alveolar bone can bear the stress without absorption are currently unclear. This study aimed to evaluate the stress distribution pattern of the interface between bone and implant by finite element analysis (FEA) to determine the appropriate range of the implant tilt angle. Methods: Cone beam computed tomography (CBCT) images of 120 patients with missing mandibular second molars and vertical bone height < 9 mm in the edentulous area were selected. The distances from the mandibular nerve canal to the buccal cortex, the lingual cortex and the alveolar ridge crest were measured by using a combination of software. The angular ranges of the buccal-lingual inclination of simulated trans-IAN implants were measured and three-dimensional finite element models were constructed in the mandibular second molar area according to the differences of the inclination angles. A vertical load (200N) was then applied to analyze the biomechanical conditions of the implant-bone interface during median occlusion. Results: The distance at the second molar from the nerve canal to the buccal cortex, lingual cortex and alveolar crest were 6.861 ± 1.194 mm, 2.843 ± 0.933 mm and 7.944 ± 0.77 mm. Trans-IAN implantation was feasible in 73.33% of patients. The minimum angle and maximum angles of the buccal-lingual inclination of the simulated implant were 19.135 ± 6.721° and 39.282 ± 6.581°. When a vertical static load of 200N was applied, the tensile stress in cortical bone gradually increased with the increase of the implant tilt angle. When the inclination angle reached 30°, the tensile stress (105.9 MPa) exceeded the yield strength (104 MPa) of cortical bone. Compared with the conventional implants, the stress peak value of the vertical ultra-short implant in cortical bone was greater than the stress peak value of the conventional implants at 10°(79.81 MPa) and 20°(82.83 MPa) and was smaller than the stress of the implant at 30°(105.9 MPa) and 40°(107.8 MPa). Therefore, when the bone mass allows, conventional-length implants should be selected whenever possible, and an operative range of the trans-IAN implantation in the mandibular second molar could be retained with an inclination angle of < 30°. Conclusions: The mandibular nerve canal at the mandibular second molar was obviously biased to the lingual side, which ensured sufficient bone mass at the buccal side. In most patients with severe mandibular atrophy, it was possible to maintain a safe distance from the nerve canal with conventional-length implants via the trans-IAN implantation technique. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the survival rate, marginal bone levels, and prosthetic success of short implants when placed in posterior areas of severely reabsorbed mandibles. Materials and Methods: A systematic review was performed of all randomized controlled trials with at least 10 patients with a control group where bone augmentations were performed that were published between January 2015 and February 2020. From 77 pertinent studies, 14 full-text publications were studied, and 6 studies fulfilled the inclusion criteria. Results: The implant survival rates of short dental implants ranged from 92% to 96.9% with a follow-up from 1 to 5 years, and the prosthetic success rate ranged from 90% to 100% during the same follow-up. The mean marginal bone level values of involved short implants ranged from -0.51 to -2.30 mm. Conclusion: The obtained data showed that short dental implants are a valid therapeutic choice to rehabilitate severe mandibular atrophy in the medium to long term. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate survival rate, marginal bone levels, and full arch prosthetic success on short implants when placed in areas of severely resorbed and edentulous mandibles. Methods: This is a systematic review of all randomized controlled trials of at least 10 patients with a control group in which bone augmentations were performed that were published between January 2010 and February 2023. Only three relevant studies met the inclusion criteria. Results: This review showed that short-term dental implant survival rates ranged from 94.2% to 97.4% with a five-year follow-up, and prosthetic success rates ranged around 62% during the same follow-up. The mean marginal bone level values of the affected short implants ranged from 0.2 mm to 0.6 mm. Conclusions: The data obtained demonstrated that short dental implants positioned with criterion and precision as a full-arch fixed support are a valid therapeutic choice for the medium–long-term rehabilitation of severe edentulous mandibular atrophy. [ABSTRACT FROM AUTHOR]

Introduction: Restoring oral function with dental implants after maxillofacial defects improves aesthetics and provides adequate nutrition to improve patients’ quality of life significantly. One of the essential methods of repairing jawbone defects is bone grafting. Graft sources may be vascularized or nonsecularized. The present study aimed to review the survival rate of implants placed in vascularized and nonvascularized bone grafts for extensive jaw reconstructions in 2010 to 2021 articles. Materials and Methods: This study is a narrative review study. In this study, research published in PubMed, Google Scholar, and Scapus databases has been reviewed by a review method and with a keyword search strategy. Results: 2815 articles were found from the mentioned databases that after removing unrelated research (2713 cases) and duplicate researches (63 cases), 39 articles remained for final review. Then, those research that were presented in the scientific conference and were in the form of abstracts or did not have a correct statistical population, were excluded from the study (18 cases) and finally 21 articles were reviewed. Conclusion: Bone jaw defects are a severe complication that affects many aspects of a person’s life. Our results showed that vascularized and nonvascularized grafts are used for mandibular and maxillary bone regeneration. Also, after maxillary reconstruction, implant survival in vascularized and nonvascularized grafts was more than 90% in the 17 cases of 21 studied articles. Also, the duration of follow-ups was from 3 months to 14 years. Interestingly, in patients with head and neck cancer whose jaws were reconstructed with bone grafts and implants were placed in them, the survival rate of implants under radiotherapy was lower than in patients without radiotherapy. Keywords: Mandibular atrophy; Atrophic maxilla; Vascularized graft; Nonvascularized graft; Implant survival.

Background: This study aimed to evaluate survival rate, marginal bone levels, and full arch prosthetic success on short implants when placed in areas of severely resorbed and edentulous mandibles. Methods: This is a systematic review of all randomized controlled trials of at least 10 patients with a control group in which bone augmentations were performed that were published between January 2010 and February 2023. Only three relevant studies met the inclusion criteria. Results: This review showed that short-term dental implant survival rates ranged from 94.2% to 97.4% with a five-year follow-up, and prosthetic success rates ranged around 62% during the same follow-up. The mean marginal bone level values of the affected short implants ranged from 0.2 mm to 0.6 mm. Conclusions: The data obtained demonstrated that short dental implants positioned with criterion and precision as a full-arch fixed support are a valid therapeutic choice for the medium–long-term rehabilitation of severe edentulous mandibular atrophy.

The edentulous atrophic posterior mandible is often a great challenge for implant rehabilitation. Although a number of treatment options have been proposed, including the use of short implants and surgical grafting techniques, in cases of severe bone atrophy, techniques for mobilization of the inferior alveolar nerve (IAN) have been shown to be efficient, with good results. Four female patients underwent IAN lateralization for prosthetic rehabilitation of the posterior mandible from 2013 to 2019, with 3 years to 5 years and 3 months of follow-up. This case series describes a new technique for mobilization of the IAN, named in-block lateralization, to facilitate access to the IAN and to reduce nerve manipulation. The implant is immediately installed (allowing nerve lateralization in unitary spaces), and the original mandibular anatomy is restored with autogenous bone from the original bed during the same surgical procedure. When well indicated and well performed, this new approach provides better and easier visualization of the IAN and safer manipulation aiming to achieve good results for implant stability and minimal risk of neurosensory disturbances, allowing rehabilitation even in unitary spaces. [ABSTRACT FROM AUTHOR]

Introduction/Objective. The most commonly used methods of treatment of mandibular fracture are not always successful in older patients. This is due to decreased regenerative ability, impaired vascularization, osteoporosis, and atrophic changes. The corresponding changes are often found in patients over 50 years of age, especially accompanied with teeth loss. The objective was to review the clinical characteristics of mandibular fractures in older patients based on a retrospective analysis of medical records. Methods. A group of patients over 50 years of age was selected and analyzed among patients with mandibular fractures who had been treated for 10 years. Results. A total of 642 patients over 50 years with 1,003 fracture lines were identified. This represents 8.53% of the total number of patients with mandibular fractures. Comorbidities were diagnosed in 67% of cases. Significant differences in the distribution of the frequency of fracture lines by localization were identified, depending on the presence or absence of occlusal contact. A high incidence rate of open fractures and bone fragment dislocation was observed both in individuals with or without occlusive contact. Conclusion. Patients over 50 years of age are a statistically important group in the general population of patients with mandibular fractures with a number of clinical features. To the author’s knowledge, this study comprises the largest number of patients over the age of 50 with mandibular fractures, including those with edentulous mandible, which ensures the required level of representation, allowing reliable clinical characterization of this contingent of patients.

The purpose of this retrospective study was to assess the feasibility of using a free fibula flap (FFF) for reconstruction of the alveolar region of the severely atrophic mandible, by determining bone stability after dental implant insertion and prosthetic rehabilitation in a series of eight female patients aged 36–65 years. Dental implant insertion was performed 3–4 months after reconstruction. Prosthetic loading was performed 3–4 months after implant insertion. The height of the reconstructed mandible after surgery was 21.20 ± 1.87 mm, with an increase of 8.80 ± 1.71 mm from the preoperative height. The height of the FFF immediately after reconstruction was 11.24 ± 1.10 mm; this showed a vertical loss of 0.99 ± 0.52 mm (8.79%) and maintenance of 91.21% of the initial height at a mean 14 months post-reconstruction. Applying the Wical and Swoope formula to estimate the original mandibular body height, it was found that the difference between this calculated height (21.17 ± 3.76 mm) and the reconstructed height (21.20 ± 1.87 mm) was only 0.03 ± 3.17 mm (0.14%). An overall insignificant decrease of 0.46 ± 1.14 cm3 in FFF volume had occurred at 3–4 months after dental implant functional loading, while in two cases an increase in volume was found (1.22 cm3 and 1.71 cm3). The good and stable results obtained show that the FFF may be used to reconstruct the whole mandibular alveolar region, with the best possible outcomes. [ABSTRACT FROM AUTHOR]

Background: Long‐term changes in masticatory function, oral health‐related quality of life (OHRQoL) and prosthetic complications in implant‐retained mandibular overdenture (IMO) wearers as a function of bone atrophy require detailed investigations. Objective: Investigating the evolution of masticatory function, OHRQoL and prosthetic occurrences of IMO wearers according to mandibular bone atrophy over 3 years of usage. Methods: This study evaluated 26 IMO wearers after 2 and 3 years of IMO loading categorised according to mandibular resorption degree into atrophic mandible (AM) and a non‐atrophic mandible (NAM) group. Masticatory function was assessed by the Masticatory Performance (MP) and Swallowing Threshold (ST) tests; OHRQoL and satisfaction via the Dental Impact on Daily Living (DIDL) questionnaire; and the prosthetic maintenance requirements and complications were monitored. Results: After the second year, the AM Group performed 32% more cycles (P =.047) than the NAM Group during the ST test. The DIDL questionnaire showed no significant difference for all domains, except for a moderate effect size in the General Performance domain after the third year. AM Group had more prosthetic occurrences (n = 109) than NAM Group (n = 60) in the first year, mainly due to Equator attachment dislodgment. During the third year, NAM Group presented a greater number of events (n = 45) than AM Group (n = 21) due to the greater number of O‐ring exchanges. Conclusion: Masticatory function and OHRQoL are not related to mandibular bone atrophy until 3 years after IMO rehabilitation. The prosthetic complications profile differs between groups, mainly in the first year. [ABSTRACT FROM AUTHOR]

Aim: Bone grafting plays a pivotal role in reconstruction of atrophic ridge in dental implants.This study made a comparison of the efficacy of allogenic and autogenic (iliac) bone grafting using the same technique (interpositional bone grafting) in increasing the mandibular anterior height. Materials and Methods: Ten partially edentulous patients who required vertical bone augmentation of the anterior mandible (having a residual ridge with 10 to 12 mm) were randomly allocated to autograft (iliac) and allograft groups. The heights of ridges were measured at three points (Right, Left, and Middle) using preoperative panoramic radiography three and six months following grafting. Results: The heights of ridges increased in all patients, but there was no significant difference between the two groups. Conclusion: This study indicated autograft and allograft had similar effects on vertical augmentation.

It is usually suggested that loading forces be transmitted to implants in the vertical direction. In 44 subjects treated with mandibular implants and overdentures, the inclination of the implant axis relative to the occlusal plane of the corresponding prostheses was measured by means of cephalometric radiographs. The degree of mandibular atrophy was also assessed. Peri-implant parameters such as plaque index, bleeding scores, and probing depths were registered on four implant sites. About 70% of the implants showed a buccal inclination, 11% showed a lingual inclination, and only 19% were found with an angle of 90 degrees. After an observation period of 5 years, no positive relationship between inclination of the implant axis, mandibular atrophy, and peri-implant findings could be established. Aspects of facial morphology and the interalveolar relationship of both jaws should be considered additional parameters and should be included in investigations concerning functional dynamics of removable dentures. [ABSTRACT FROM AUTHOR]

An important complication during insertion of implants in atrophic mandibles is the fracture that can be induced by preparation of the cavity. We designed this study to identify which configuration of cavities in the interforaminal region was the least likely to fracture. An electromechanical testing machine was used to measure breaking loads of specifically-designed synthetic models of atrophic mandibles. The implant cavities correlated with the common clinical patterns. Intact atrophied synthetic mandibles broke at a mean (SD) load of 729.48 (59.94) N (control group). Models with four different configurations of cavities fractured as follows: two short, wide cavities (8 x 4.2 mm) at a mean (SD) load of 569.17 (67.7) N; two long, thin cavities (15 x2.8 mm) at a load of 563.40 (62.0) N; four short, wide cavities (8 x 4.2 mm) at a load of 667.01 (71.89) N; and four long, thin cavities (15 x 2.8 mm) at a load of 409.50 (43.61) N. Biomechanical findings showed that there was a greater risk of fracture of atrophic mandibular models in long, thin implant cavities with more preparation sites. Each cavity prepared for an implant increased the risk of fracture in an atrophic mandible. The risk of fracture is greatest with long, thin cavities. [ABSTRACT FROM AUTHOR]

Copyright of Implant Dentistry is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives Fractures of the atrophic edentulous mandible are a rare complication that can become severe after the insertion of dental implants. This in vitro study investigated the effects of different implant settings varying in number, diameter, and length. and the influence of a fixed bar. Materials and methods In biomechanical experiments on artificial mandibles, an unmodified reference group, four implant settings with two different implants, and the effect of adding a fixed bar to these settings were tested. All specimens were loaded with incisal biting forces until failure due to fracture. Results Implants weakened all specimens significantly compared with those in the reference group. Without a fixed bar, four short and thick implants showed the best results, with high significance. With a fixed bar, four long and thin implants withstood the highest loads. The addition of fixed bars reduced the differences between the implant settings. Fixed bars did not show increased stability for all groups; however, these groups showed a higher mean strength. Conclusions Four implants with a short and thick design should be the first choice when implants are placed without a fixed bar in an atrophic mandible. With a fixed bar, four long and thin implants should be used. [ABSTRACT FROM AUTHOR]

Copyright of Implant Dentistry is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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. [ABSTRACT FROM AUTHOR]

Abstract: We studied the result of vertical distraction osteogenesis in 34 patients as a method of restoring vertical bone height in atrophic mandibles. Cephalometric radiographs were obtained preoperatively, immediately after the installation of the distractor, at the end of the active distraction period (1–2 weeks), before placement of implants, after a consolidation period of 12 weeks, and annually thereafter. Particular attention was paid to the changed position of the upper segment in relation to the basal segment, compared with before and after active distraction. To monitor the position of the distracted upper bone segment, both the improvement in bony height and the angle of the distracted upper bone segment were scored using the menton-pogonion line as a reference plane. Surprisingly in nearly all patients there was a backward rotation of the segment with lingual-tipping of the upper segment by a mean of 12° that meant that in such cases only 87% of the maximum gain in bony height could be achieved. As a consequence of the backward tipping of the top of the distracted alveolar ridge, the position of the implants was also more lingually directed. However, in all cases sufficient bony volume was achieved to allow placement of implants. Distraction osteogenesis is a successful way of restoring atrophic mandibles to gain sufficient bony volume to allow placement of implants. However, the vector of distraction is unpredictable. [Copyright &y& Elsevier]

This retrospective study aims to investigate and compare the results obtained with the transmandibular implant (TMI) in two different hospital situations. Group I were patients treated in a teaching hospital since 1984 by a varying group of surgeons and prosthodontists with a varying degree of experience with the TMI. Group II were patients treated in 1993 and 1994 by experienced surgeons and prosthodontists in the hospital where the TMI was originally developed. In group I, a relatively high frequency of reversible (45·4%) and irreversible – i.e. implant loss – (15·2%) complications occurred. In group II, no implants were lost and reversible complications were reported in 10·8% of the patients. In general, the patients of both groups were quite satisfied with the result of the treatment. In both groups, limited bone loss around the implant posts could be observed. An increase in the height of the mandibular bone distal of the lateral posts was frequently observed, especially in group II. It is concluded that both very favourable and less favourable results can be obtained with the TMI. In this study the best results are found in a highly specialized TMI centre, where patients are treated – with only uncompromised implant-posts – by a small group of experienced surgeons and prosthodontics with accurate application of the existing guidelines. [ABSTRACT FROM AUTHOR]

Copyright of Mund-, Kiefer- und Gesichtschirurgie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Severely atrophic mandible fractures are frequently a challenge to treat. Virtual surgical planning (VSP) uses three-dimensional computed tomographic (CT) scans that can be translated into stereolithographic models to fabricate surgical templates, facilitating intraoperative procedures. The purpose of this article is to describe the reconstruction of two cases of severe atrophic mandible fracture using VSP. Two elderly edentulous/partially dentate patients who presented with fractures of their mandibles and who underwent reconstruction using VSP were included. Both had Class III atrophy at the region of the fracture. While both fractures were complex, the mechanism of injury differed with one being a tractor accident and the other being a pathologic fracture. Both patients presented with critical medical conditions. CT scans were obtained on both. The displaced segments were aligned virtually using mirror images and the midline of the maxilla. Three-dimensional models were fabricated to allow preoperative contouring of 2.5-mm reconstruction plates. Patients were operated under general anesthesia and fractures reduced and stabilized with 2.5-mm reconstruction plates placed at the lateral border of the mandible. Average treatment time for both patients was a little over 2 hours. There was good reduction with both. VSP is a valuable tool to assess and reduce complex fractures with less surgical time and predictable results.

The management of atrophic mandibular fractures in edentulous patients represents an insidious issue for the maxillofacial surgeon due to the biological and biomechanical conditions that are unfavorable for fracture fixation and bone healing. The purpose of this study was to evaluate the results of the treatment of atrophic mandibular fractures and to compare the outcomes of different plating systems used for stabilization. We selected a study group of 16 patients with fractures of completely edentulous atrophic mandibles who were treated in our department between 2004 and 2010. All patients were surgically treated by open reduction and internal rigid fixation using 2.0-mm large-profile locking and 2.4-mm locking bone plates. All patients achieved a complete fracture healing and fast functional recovery of mandibular movements without intraoperative or postoperative surgical complications. The results of our study demonstrated the efficacy of this type of treatment in association with a low postoperative complication rate, a reduction in the recovery time, and the possibility to have an immediately functional rehabilitation. There were very similar results using each of the two bone plating methods considered: no case had hardware failure or nonunion of the fracture. The 2.0-mm large locking plate is thinner, exposes through the soft tissues less frequently, and is much easier to shape and adapt to the mandibular anatomy. However, the 2.4-mm locking plate system still represents the reference hardware in the condition of severe bone atrophy.