Impact of Bone Augmentation of Facial Bone Defect around Osseointegrated Implant: A Three Dimensional Finite Element Analysis

(1) Background: When dental implants are placed at the esthetic zone, facial bone fenestration might be expected. This study aimed to evaluate the biomechanical effect of bone augmentation around implants with facial bone fenestration defects using the finite element method. (2) Methods: An anterior maxillary region model with facial concavity was constructed with a threaded implant inserted following the root direction, resulting in apical threads exposure to represent the fenestration model. Several bone coverage levels were simulated by gradually shifting the deepest concavity point buccally, mimicking bone augmentation surgeries with different bone fill results. Oblique forces were applied, and analysis was performed. (3) Results: Peak compressive stress magnitude and distribution varied according to the level of exposure and facial concavity depth. The fenestration model demonstrated a slightly lower peak peri-implant bone stress, smaller implant displacement, and smaller bone volume with strain levels above 200 µ strain. A gradual increase in compressive stress, implant displacement, and bone volume exhibited strain level above 200 µ strain was observed with the increased bone fill level of the facial bone fenestration. (4) Conclusions: Exposure of implants apical threads at the maxillary anterior region does not significantly affect the peri-implant stress and strain results. However, increasing the buccolingual width and eliminating the buccal concavity might increase the peri-implant bone volume exhibited favorable loading levels.

Impact of soft tissue graft on the preservation of compromised sockets: a randomized controlled clinical pilot study

The aim of this pilot study was to evaluate the impact of the association of free gingival graft (FGG) or collagen-matrix xenograft (CMX) to deproteinized bovine bone graft (DBBG) on the preservation of post-extraction sockets with facial-wall defects. Sixteen patients who presented a maxillary tooth with a facial bone defect and indication of extraction were selected. After the surgical procedure, all the post-extraction sockets were filled with DBBG and covered with a collagen membrane. The cervical part of the socket was then sealed with either FGG or CMX. Clinical and tomographic analyses were performed at baseline and 4 months after the grafting procedure. The FGG sockets showed higher values for the width of the bone ridge than the CMX sockets at 4 months. There was no difference regarding biopsy composition. In conclusion, regardless of the type of soft tissue graft used, socket preservation with DBBG at sites presenting facial bone defects enabled implant placement without further guided bone regeneration, whether the sockets were sealed with FGG or CMX.

CBCT analysis of the tissue thickness at immediate implant placement with contour augmentation in the maxillary anterior zone: a 1-year prospective clinical study

Background Immediate implant placement with simultaneous contour augmentation such as guided bone regeneration (GBR) or connective tissue grafting (CTG) has been widely performed. However, few prospective studies have evaluated both peri-implant bone and soft tissue changes between the preoperative and postoperative periods. The purpose of this study is to quantify the horizontal dimensional changes of the facial bone and soft tissue following immediate implant placement with contour augmentation. Material and methods Twenty patients who underwent immediate implant placement in the anterior maxilla received GBR and CTG (test group) or GBR only (control group). Cone-beam computed tomography (CBCT) scans were taken preoperatively and 1 year after the definitive prosthesis connection, and then, they were superimposed. On the CBCT images of the two stages, the horizontal distance from the implant platform to the facial bone surface (BW) and the horizontal soft tissue width (GW) were measured at the implant platform level and 2 mm apical to the implant platform level. The sum of BW and GW (=TW) was used to assess the facial mucosal contour. Results BW decreased significantly from preoperative to 1 year after prosthesis connection with a mean decrease of 0.47 mm (P =0.021) in the control group and a mean decrease of 0.50 mm (P = 0.019) in the test group at the implant platform level. GW increased significantly with a mean increase of 1.37 mm (P =0.005) in the test group at the implant platform level. TW decreased significantly with a mean decrease of 0.46 mm in the control group (P =0.049) but increased significantly with a mean increase of 0.87 mm in the test group (P =0.005) at the implant platform level. Conclusions Immediate implant placement with CTG showed a soft tissue gain of 1.37 mm compensated for bone resorption, thus still preserving the preoperative mucosal contour. CTG should be performed with immediate implant placement in cases where preoperative mucosal contours need to be maintained.

Rational for Maxillofacial Fracture Plate Removal

Aim: To estimate indications and frequency of plate removal in patient treated for maxillofacial fractures. Method; In this retrospective study, records were reviewed from March 2015 to March 2018, over a period of 3 years. 139 Maxillofacial trauma patients treated with Open reduction and Internal Fixation with 202 plate, Result; In 139 patients, 202 plates were implanted for bone fractures. In total, 128(92%) were male and 11(8%) were female, 32(23.02%) had revisited with complaint and subsequently 47(23.26%) plates were removed. Mandible was commonest location where majority of the plates32(68.08%) were removed. Most common reason for plates removal was infection 20(42%). Minimum time for plate in situ was 3 months. Conclusion; the reason for plate removal is multifactorial. Establishing measures to minimize plate related complication and avoid patients from further invasive procedures. Keywords: Facial Bone Fracture, Osteosynthesis Plate, Plate Removal Trauma.

A Cross-Sectional Study to Assess the Risk Factors for Hypoesthesia after Repair of Facial Fractures

Background: Hypoesthesia occurs as a result of injuries resulting in injury to the nerve fibres. The causes of injury include direct harm from the needle injections, around the nerve fibres, mechanical injuries resulting in an indirect pressure into the mandibular canal, during the dental surgical procures, as well as the toxicity of the local anaesthetic agents. Methods: This cross-sectional research was conducted by recruiting N=79 adult individuals (>18 years), who had visited the district hospital for acquiring clinical assistance and treatment of facial muscles or nerve-related complications in August 2020. Data collection for this research was carried out by using a specially designed questionnaire, which facilitated in acquiring data related to aetiology of trauma, identification of the hypoesthesia area, as well as the clinical complications experienced by the respondents. The clinical reports of the patients were also collected for analysing the hypoesthesia area. SPSS was utilised for data analysis, and statistical tests were conducted for assessing the risk factors for hypoesthesia after repair of facial fractures. Results: The statistical tests revealed that only a small percentage of the sample population, i.e., (N=9) or 11.8% experienced the facial bone fracture, male respondents had more exposure to the facial bone fractures, as compared to the females (Mean=1.81, SD= 0.397), and the individuals below 25 years of age had high exposure of facial bone fracture (Mean=1.78, SD= 0.428). A significant majority of hypoesthesia cases were at mandible, and orbit region. Conclusion: The dental treatment resulting in nerve manipulation results in nerve elongation, nerve compression, contributing to transient hypoesthesia. Hypoesthesia might also lead to other clinical complications.