Incidence of straight and angulated screw channel following immediate implant placement in esthetic zone: A simulated cone-beam computed tomography study.

STATEMENT OF PROBLEM: The demand for immediate implant placement (IIP) in the esthetic zone is rapidly increasing. Despite the treatment's benefits, the sagittal root position often dictates implant angulation, commonly necessitating the use of cement-retained restorations. This study investigates the impact of angulated screw channel on IIP in the esthetic zone. PURPOSE: The purpose of this cone-beam computed tomography (CBCT) study was to determine the probability of IIP in the esthetic zone, using four different implant angulations. MATERIALS AND METHODS: A retrospective review of CBCT images was conducted and accessed on 9 June 2021. The midsagittal images of maxillary anterior teeth were input into an implant planning software (Implant Studio®). Bone Level X Straumann® implant (BLX 3.5, 3.75, 4.0, 4.5, 5.0 mm) and Bone Level Tapered implant (BLT 2.9, 3.3 mm) were selected for 3D implant planning of IIP in the esthetic zone. The frequency distribution and probability of IIP were recorded and compared among all maxillary anterior teeth. RESULTS: CBCT images from 720 teeth (120 patient) were evaluated, revealing an overall probability of IIP in the esthetic zone is 76.11% (548/720). Different implant restoration type was evaluated in this study, with the following results; straight screw-retained prosthesis at 3.47% (19/548), cement-retained prosthesis at 14.59% (80/548) and angle screw-retained prosthesis at 85.40% (468/548). CONCLUSION: IIP with traditional straight screw-retained prosthesis demonstrated the lowest probability. Nevertheless, the use of angulated screw channels enhances the probability of achieving straight screw-retained prostheses. CLINICAL IMPLICATIONS: The angulated screw channel is essential for increasing the probability of screw-retained prosthesis in IIP in the esthetic zone. However, limitation in screw angle correction still necessitate the use of cement-retained prostheses for numbers of patients undergoing IIP.

Reamer-scraping and implant-pushing technique for transcrestal sinus floor elevation.

Transcrestal maxillary sinus floor elevation is an effective method to solve the problem of insufficient bone height in the posterior maxillary region. However, current methods, such as osteotome sinus floor elevation, cushioned grind-out technique, Smart Drill technique, etc., require specialized surgical tool boxes. In this article, we introduce a new method of transcrestal maxillary sinus elevation that uses built-in reamers of various implant systems to scrap residual bone at the sinus floor and uses the implant to push the sinus membrane during implant placement. This technique is easy to operate and time saving and has a low rate of sinus membrane perforation. After a one-year follow-up observation of 146 people and 175 implants, the endo-sinus bone gains were 5.00 (4.70, 5.30) mm and 2.10 (1.40, 2.70) mm in the group of 3 mm≤residual bone height (RBH)<5 mm and the group of 5 mm≤RBH<8 mm, respectively, which can meet the clinical requirements of implant stability. This technique is suitable in generalizing dental implantation.

Retention of implant retained obturator using two implant placement configurations for maxillectomy cases: in-vitro study.

BACKGROUND: Implant-retained obturators for maxillectomy cases have several advantages over traditional obturators but prosthetic design for specific conditions after maxillary resection has several challenges and the appropriate implant placement configuration is essential for improving retention and the stability of the implant-retained obturator. OBJECTIVES: The present study aimed to assess the retention force of using linear and nonlinear implant placement configurations using ball and socket attachment in implant-retained obturators at the initial retention and after simulation of six months of use. MATERIALS AND METHODS: Two identical epoxy resin maxillary models of a completely edentulous unilateral maxillary defect (Brown's class IIb) were used for implant placement, in the first model three implants were arranged with linear placement configuration, and in the second model three implants were arranged in nonlinear placement configuration. For proper sample sizing, 26 models and obturator were used. Two equal groups of obturators (13 for each group) were constructed, each with a different implant placement configuration. Both groups used the same attachment design (a non-splinted ball attachment). Using a cyclic loading machine that served as a dental insertion and removal simulator, each study group was subjected to 500 tension-compression cycles simulating 6 months of use. Using the universal testing machine, each obturator was removed at a speed of 50 mm/min for the crosshead. peak load to dislodgement was measured at the initial retention and after the simulations of six months of use. Data were analyzed using independent and paired t-tests while percent change was analyzed using the Mann Whitney U test. RESULTS: There were a statistically significant differences in retention between the nonlinear implant placement configuration for Brown's class IIb maxillectomy and the linear implant placement configuration at initial retention evaluation with p-value of < 0.0001 and after simulation of six months of usage with p-value of < 0.0001 Also, after simulation of 6 months of use group I lose - 24.87 (10.16) % of its retention while group II lose - 17.49 (7.78) %. CONCLUSIONS: Non-linear implant placement is more retentive at the initial retention and after simulation of six months of use than linear and loses less retention after usage.

Primary stability with osseodensification drilling of dental implants in the posterior maxilla region in humans: A systematic review.

Currently, a new non-subtractive drilling technique, called osseodensification (OD), has been developed. It involves using specially designed drills with large negative cutting angles that rotate counterclockwise, causing expansion through plastic bone deformation, thus compacting the autologous bone to the osteotomy walls, which improves the primary stability of the implant.The present systematic review aimed to determine whether the OD technique can increase the primary stability of dental implants in the posterior maxilla region as compared to the conventional drilling (CD) technique.Five databases were searched up to June 30, 2022. The inclusion criteria embraced observational clinical studies, randomized and non-randomized controlled trials, human studies in vivo, comparing OD and CD, with the measurement of the primary stability of implants in the posterior maxilla region by means of the implant stability quotient (ISQ). The tools used to assess the risk of bias were RoB 2 and the NewcastleOttawa Scale (NOS).Seven articles met the inclusion criteria, with 4 classified as having a low risk of bias and 3 with a moderate risk of bias. The OD technique consistently demonstrated an average ISQ value of 73 KHz across all studies, whereas CD yielded an average value of 58.49 kHz (p < 0.001 for 5 articles).It can be concluded that in comparison with CD, OD improves primary stability at baseline in low-density bone, such as the maxilla.

Effect of Needle Insertion Angle on Pain During Labial Infiltration Anesthesia of the Anterior Maxilla: A Randomized Clinical Trial.

OBJECTIVES: This study aimed to assess the effect of needle insertion angle on pain during labial infiltration anesthesia in the anterior maxillary region. MATERIAL AND METHODS: In this parallel-design randomized clinical trial, participants were randomly assigned to four groups for labial infiltration anesthesia of the anterior maxilla. Local anesthesia was performed with needle orientation parallel to the longitudinal axis of the tooth using a conventional syringe (Syringe-0), needle at α angle with a conventional syringe (Syringe-α), computer-controlled local anesthetic delivery (CCLAD) device parallel to the longitudinal axis of the tooth (CCLAD-0), and CCLAD at α angle (CCLAD-α). The heart rate (HR), blood pressure (BP), and respiratory rate (RR) of participants were measured before needle insertion, immediately after needle insertion, and immediately after the injection by a vital signs monitor. The level of pain experienced by participants was quantified using a numerical rating scale (NRS). Data were analyzed by repeated-measures ANOVA and regression models (α = 0.05). RESULTS: Thirty-six participants aged from 21 to 60 years, with a mean age of 35.36 years were recruited. The mean pain scores were 7.44, 4.67, 2.89, and 0.67 in groups Syringe-0, Syringe-α, CCLAD-0, and CCLAD-α, respectively (p < 0.001). Age and sex had no significant effect on pain scores (p = 0.914 and p = 0.702, respectively). The four groups had no significant difference in vital signs (p > 0.05). CONCLUSIONS: Injection at an α angle and the application of CCLAD can be used in clinical practice to decrease the pain experienced by participants during labial infiltration anesthesia of the anterior maxilla. TRIAL REGISTRATION: Iranian Registry of Clinical Trials: IRCT20230719058849N1.

A retrospective study on the influence of inclination of cusp on implant marginal bone height in patients with periodontal disease.

PURPOSE: To investigate the correlation between the marginal bone height of implants in the posterior maxilla of patients with periodontal disease and the inclination of cusp, providing a theoretical basis for the occlusal design of implant restorations in such patients.  Methods: A total of 80 patients with periodontal disease who underwent implant restoration in the posterior maxilla (55 men and 25 women; mean age 56.66 ± 12.70 years) were selected, with a total of 80 implant restorations (one implant restoration per patient). In addition to recording the main research factor of the inclination of cusp, general patient information, implant characteristics and restoration characteristics were taken, and retrospective analysis of the case data and imaging data of the 80 patients from over 3 years was conducted. Cone beam computed tomography was performed preoperatively and 3 years after implant loading to measure and calculate the marginal bone height of the implants using the One Volume Viewer software. Correlation analysis was performed to determine the relationship between the inclination of the cusp and marginal bone height.  Results: There was a positive correlation between the inclination of cusp and the marginal bone height of the implants, with a correlation coefficient of 0.661 (p < 0.001); the diameter of the implants, implant type and restoration type were negatively correlated with the marginal bone height of the implants, with correlation coefficients of -0.364 (p = 0.001), -0.232 (p = 0.038) and -0.298 (p = 0.007), respectively.  Conclusion: When designing the occlusion of implant restorations in the posterior maxilla of patients with periodontal disease, it is advisable to appropriately reduce the restoration's inclination of cusp.

Extreme midface injury and superior maxillary impaction in an adolescent.

We present a case of an adolescent who sustained multiple facial fractures following a high-speed, head-on skiing collision. The patient presented to a level 1 trauma centre with bilateral LeFort I, LeFort II, naso-orbital ethmoid fractures and superior maxillary displacement to the level of the orbits requiring a staged operative approach to (1) disimpact the maxillary LeFort I segment and (2) reduce and fixate the multilevel facial fractures. The patient was discharged home with close follow-up, and after 1 year, had preservation of appropriate facial proportions without complications. This case study focuses on the triage, management and surgical planning of paediatric midface fractures, which are relatively uncommon to treat. Special considerations for repairing facial fractures in adolescents are discussed.

Correlation between oral cavity volume and upper airway changes in skeletal Class III patients undergoing bimaxillary orthognathic surgery: a pilot cone-beam computed tomography study.

OBJECTIVES: To evaluate changes of the upper airway and oral cavity volumes in patients with skeletal Class III malocclusion undergoing bimaxillary orthognathic surgery, and to analyze the correlation between postoperative upper airway decrease and the amount of jaw movement and oral cavity volume reduction. MATERIALS AND METHODS: Thirty patients (16 males and 14 females) undergoing bimaxillary surgery were included. Three-dimensional reconstruction of the upper airway and oral cavity were performed using preoperative (T0) and postoperative (T1) (6 months) cone-beam computed tomography scans. RESULTS: The volume, sagittal area and minimum cross-sectional area of the upper airway were diminished (P < .001). The decrease in volume and minimum cross-sectional area in the oropharyngeal region of the upper airway were weakly correlated with B-point posterior movement (P < .05). Total oral cavity volume was decreased, with maxillary oral volume increasing and mandibular oral volume decreasing (P < .001). Upper airway decrease was highly correlated with total oral volume reduction and mandibular oral volume reduction, with the most significant correlation being with total oral volume reduction (P < .001). CONCLUSIONS: Class III bimaxillary surgery reduced the volume, sagittal area, and minimum cross-sectional area of the upper airway as well as oral cavity volume. Upper airway changes were weakly correlated with anterior-posterior mandibular movement but significantly correlated with oral cavity volume changes. Thus, oral cavity volume reduction is a crucial factor of upper airway decrease in patients with skeletal Class III malocclusion undergoing bimaxillary orthognathic surgery.

Changes in the upper airway and its surrounding structures after bimaxillary surgery in patients with cleft-related Class III deformity.

OBJECTIVES: To compare upper airway changes following bimaxillary surgery for correction of Class III deformity between patients with unilateral cleft lip and palate (UCLP) and bilateral cleft lip and palate (BCLP) and to compare the preoperative and postoperative upper airway among patients with UCLP and BCLP to healthy controls. MATERIALS AND METHODS: Sixty adults with CLP-related skeletal Class III deformity (30 UCLP and 30 BCLP) who consecutively underwent bimaxillary surgery were studied retrospectively. Cone-beam computed tomography (CBCT) was performed before and after surgery to measure upper airway and movements of facial skeletal and surrounding structures. CBCT images from 30 noncleft skeletal Class I adults, matched by age, gender, and body mass index and without surgical intervention, served as controls. RESULTS: After surgery, the volume of the nasopharynx increased in patients with CLP (both P < .001). Patients with CLP did not differ from controls in postoperative volume of the nasopharynx or oropharynx. However, the nasal cavity differed significantly between patients with CLP and controls (P < .001). CONCLUSIONS: After bimaxillary surgery, the nasal cavity of patients with CLP differed significantly compared with the controls. Volumes of the nasopharynx and oropharynx did not differ between patients with CLP after surgery and controls.

Efficacy of modified anterior maxillary segmental distraction osteogenesis based on 3D visualisation for the treatment of maxillary hypoplasia among adolescents with cleft lip and palate.

BACKGROUND: This study evaluates a three-dimensional (3D) visualisation design combined with customized surgical guides to assist anterior maxillary segmental distraction osteogenesis (AMSDO) in correcting maxillary hypoplasia in adolescents with cleft lip and palate (CLP), focusing on treatment outcomes, satisfaction and the validity of 3D planning. METHODS: This retrospective cohort study was conducted at a single hospital in China. Between January 2020 and December 2023, 12 adolescents with CLP with maxillary hypoplasia were included. An advanced 3D simulation was used to convey the treatment strategy to the patients and their families. A customized surgical guide and distraction osteogenesis device were designed. Cephalometric analysis evaluated AMSDO changes and long-term stability. Patient satisfaction was assessed. The Chinese version of the Child Oral Health Impact Profile was used to evaluate the children's oral health-related quality of life before and after treatment. The postoperative outcomes were compared with the planned outcomes by superimposing the actual postoperative data onto the simulated soft tissue models and calculating the linear and angular differences between them. RESULTS: One patient experienced postoperative gingivitis, yielding an 8.33% complication rate. Most patients (83.33%) were highly satisfied with the target position, with the rest content. Cephalometric analysis showed significant improvements in various indices post-traction. Quality-of-life scores significantly improved post-treatment. The discrepancies in facial soft tissue between the simulated and actual results were within clinically satisfactory ranges. CONCLUSIONS: Digitally designed surgical guides effectively treat maxillary hypoplasia in adolescents with CLP, ensuring stability, reducing complications, reducing dependency on operator experience, and enhancing satisfaction and health outcomes. Although the simulated results were clinically acceptable, it is important to inform patients of potential variations in the predicted soft tissue.

A Review of Sinus Floor Elevation Techniques: Lateral Window, Transcrestal, Graft Materials, and Biologics.

Various approaches to implant placement in the atrophic posterior maxilla are currently advocated in the literature. Such strategies range from the use of block bone graft, to short, tilted, and zygomatic implants, to sinus floor elevation (SFE). SFE has shown to be a predictable surgical procedure to increase bone height in the posterior maxilla. This article provides a narrative overview of SFE techniques, including a modified localized management of sinus floor technique in fresh molar extraction sockets.

Digital analysis of the human maxilla to enable semistandardized template tool reconstructions with free fibula transplants.

OBJECTIVES: This study analyzed the human maxilla to support the development of mean-value-based cutting guide systems for maxillary reconstruction, bridging the gap between freehand techniques and virtual surgical planning (VSP). MATERIALS AND METHODS: This retrospective cohort study used routine CT scans. DICOM data enabled 3D modelling and the maxilla was divided into four regions: paranasal (R1), facial maxillary sinus wall (R2), zygomatic bone (R3) and alveolar process (R4). Surface comparisons were made with a reference skull. Statistical analyses assessed anatomical variations, focusing on mean distance (Dmean), area of valid distance (AVD), integrated distance (ID) and integrated absolute distance (IAD). The study addressed hemimaxillectomy defects for two-segmental reconstructions using seven defined bilateral points to determine segmental distances and angles. RESULTS: Data from 50 patients showed R2 as the most homogeneous and R4 as the most heterogeneous region. Significant age and gender differences were found in R3 and R4, with younger patients and females having more outliers. Cluster analysis indicated that males had R1 and R3 positioned anterior to the reference skull. The mean angle for segmental reconstruction was 131.24° ± 1.29°, with anterior segment length of 30.71 ± 0.57 mm and posterior length of 28.15 ± 0.86 mm. CONCLUSIONS: Anatomical analysis supported the development of semistandardized segmental resection approaches. Although gender and anatomical differences were noted, they did not significantly impact the feasibility of mean-value-based cutting-guide systems. CLINICAL RELEVANCE: This study provides essential anatomical data for creating cost-effective and efficient reconstruction options for maxillary defects, potentially improving surgical outcomes and expanding reconstructive possibilities beyond current techniques.

Accuracy of dynamic computer-assisted implant surgery in fully edentulous patients: An in vitro study.

OBJECTIVES: To compare miniscrew versus bone tracing registration methods on dental implant placement accuracy and time efficiency in edentulous jaws using a dynamic computer-assisted implant surgery (d-CAIS) system. METHODS: Twelve fully edentulous maxillary models were allocated into two groups: miniscrew tracing (MST) group, where registration was performed by tracing four miniscrews; and bone tracing (BT) group, where registration was conducted by tracing maxillary bone fiducial landmarks. Six implants were placed on each model using the X-Guide® d-CAIS system. Pre- and postoperative cone-beam computed tomography (CBCT) scans were superimposed to evaluate implant placement accuracy. The time required for registration and the overall surgery time were also recorded. RESULTS: Thirty-six implants were placed in each group. The MST group showed significantly lower mean angulation deviations (mean difference (MD): -3.33°; 95 % confidence interval (CI): -6.56 to -0.09); p = 0.044), 3D platform deviations (MD: -1.01 mm; 95 % CI: -1.74 to -0.29; p = 0.006), 2D platform deviations (MD: -0.97 mm; 95 % CI: -1.71 to -0.23; p = 0.010), and 3D apex deviations (MD: -1.18 mm; 95 % CI: -1.92 to -0.44; p = 0.002) versus the BT group. The overall surgery time was similar for both groups (MD: 6.10 min.; 95 % CI: -0.31 to 12.51; p = 0.06), though bone tracing required significantly more time compared with miniscrew registration (MD: 4.79 min.; 95 % CI: 2.96 to 6.62; p < 0.05). CONCLUSIONS: Registration with MST increases the accuracy of implant placement with a d-CAIS system in edentulous jaws compared with the BT method, and slightly reduces the overall surgery time. CLINICAL SIGNIFICANCE: Miniscrew tracing registration improves implant placement accuracy in comparison with bone tracing registration.

Biomechanical characteristics of maxillary anterior incisor, conventional immediate implantation and socket shield technique - A finite element analysis and case report.

BACKGROUND: To prevent the absorption and collapse of the labial bone plate of the anterior teeth, immediate implantation and socket shield technique have been increasingly applied to anterior dental aesthetic implant restoration. OBJECTIVE: To provide a biomechanical basis for implant restoration of maxillary anterior teeth, finite element analysis was used to investigate the stress peak and distribution in different anatomical sites of natural teeth, conventional immediate implantation and socket shield technique. METHODS: Three maxillary finite element models were established, including a maxillary incisor as a natural tooth, a conventional immediate implantation and a socket shield technique. A mechanical load of 100 N was applied to simulate and analyze the biomechanical behavior of the root, periodontal ligament (PDL), implant and surrounding bone interface. RESULTS: The stress distribution of the natural tooth was relatively uniform under load. The maximum von Mises stress of the root, periodontal ligament, cortical bone and cancellous bone were 20.14 MPa, 2.473 MPa, 19.48 MPa and 5.068 MPa, respectively. When the conventional immediate implantation was loaded, the stress was mainly concentrated around the neck of implant. Maximum stress on the surface of the implant was 102 MPa, the cortical bone was 16.13 MPa, and the cancellous bone was 18.29 MPa. When the implantation with socket shield technique was loaded, the stress distribution of the implant was similar to that of immediate implantation. Maximum stress on the surface of the implant was 100.5 MPa, the cortical bone was 23.11 MPa, the cancellous bone was 21.66 MPa, the remaining tooth fragment was 29.42 MPa and the periodontal ligament of the tooth fragment was 1.131 MPa. CONCLUSIONS: 1. Under static loading, both socket shield technology and conventional immediate implantation can support the esthetic restoration of anterior teeth biomechanically. 2.Under short-term follow-up, both immediate implant and socket shield technology achieved satisfactory clinical results, including bone healing and patient satisfaction. 3.The stress distribution is mainly located on the buccal bone surface of the implant and is associated with resorption of the buccal bone plate after implant replacement in both socket shield technology and conventional immediate implantation. 4.The presence of retained root fragment had an impact on the bone graft gap. In immediate implantation, the peak stress was located in the cortical bone near the implant position, while in socket shield technology, the peak stress was at the neck of the cortical bone corresponding to the retained root fragment.

Clinical outcomes of gingivoperiosteoplasty for unilateral cleft lip and palate performed in early childhood.

Conventional gingivoperiosteoplasty (GPP) performed during infancy adversely affects maxillary development. However, the outcomes of this procedure in early childhood have rarely been reported. Therefore, we examined the postoperative outcomes of GPP conducted in patients aged 1.5 years with unilateral cleft lip and palate (UCLP). This study included 87 non-syndromic patients with complete UCLP who had undergone early two-stage palatoplasty during the 1999-2004 period. The protocol comprised soft palate plasty at 1 year of age and hard palate closure at 1.5 years of age. In the GPP group (n = 34), we introduced the GPP procedure during hard palate closure; in the non-GPP group (n = 53), the labial side of the alveolar cleft remained intact. We examined computed tomography images taken at 8 years of age to observe bone formation at the alveolar cleft site. We also conducted cephalometric analysis to examine maxillary development at 12 years of age. Bone bridges at the alveolar cleft site were observed in 92% and 5.6% of the GPP and non-GPP groups, respectively. Moreover, 56% of the GPP group did not require secondary alveolar bone grafting (sABG), whereas all the patients in the non-GPP group underwent sABG. No statistically significant differences were noted in the maxillary anteroposterior length (GPP: 45.5 ± 3.7 mm, non-GPP: 45.9 ± 3.5 mm, p = 0.67) and sella-nasion-point A angle (GPP: 75.6 ± 4.5°, non-GPP: 73.8 ± 12.6°, p = 0.49). This study's findings suggest that GPP performed at 1.5 years of age minimises the necessity of sABG and does not exert a negative influence on maxillofacial development.

MISMARPE protocol: minimally invasive surgical and miniscrew-assisted rapid palatal expansion.

OBJECTIVE: The purpose of this article is to present the MISMARPE technique, a new minimally invasive surgical procedure to treat maxillary transverse atresia in adult patients under local anesthesia and on an outpatient basis. TECHNIQUE DESCRIPTION: The technique consists of miniscrew-assisted rapid palatal expansion (MARPE) associated with a minimally invasive approach using maxillary osteotomies, latency and activation periods until the desired expansion is achieved. The present MISMARPE technique was performed in 25 consecutive cases with a success rate of 96%, yielding good skeletal outcomes with minimal trauma. The expander appliances, with their anchorage types, and a description of the surgical steps of the MISMARPE technique are presented. CONCLUSION: MISMARPE is a new and effective alternative for less invasive treatment of maxillary transverse deficiency in adults, compared to conventional surgery. Emphasis is placed on the importance of systematic and well-established protocols, for executing the procedures safely and predictably.

A new classification for pterygomaxillary implants and its related surgical implications: a retrospective cohort study.

BACKGROUND: To provide a novel classification for all implants in the maxillary retromolar region to simplify surgical design, reduce surgical risks, and guide clinicians in clinical decision-making. METHODS: A total of 180 patients with bilateral partial or completely edentulous atrophic posterior maxillae who had received or were scheduled to receive pterygomaxillary implants were included in this study. Cone-beam computed tomography was performed, and the sagittal and coronal images were acquired at 110 kV and 10 mA. The exposure volume was 120 mm in diameter and 80 mm in height. The pterygomaxillary implants were divided into three different types based on the anatomical structures the implants passed through. RESULTS: The average age of the 180 patients was 69 (range: 39-89) years; 99 were men and 81 were women. All the patients exhibited 360 pterygomaxillary implant sites. However, during mimic implantation, 14 implant sites were excluded due to severe resorption of the tuberosity, very small pterygoid plates, or variations in the descending palatal artery configuration. Of the 346 pterygomaxillary implant sites, 24.0% (83/346), 40.7% (141/346), 22.0% (76/346), and 13.3% (46/346) were classified as Types I, IIa, IIb, and III, respectively. CONCLUSIONS: Type II pterygomaxillary implants were the most commonly used in the novel classification. Different types of pterygomaxillary implants should follow specific designs and surgical strategies to achieve optimal outcomes.

Influence of titanium and titanium-zirconium alloy as implant materials on implant stability of maxillary implant retained overdenture: a randomized clinical trial.

BACKGROUND: Long-term success of implant restoration depends on many factors one of them is the sufficient implant stability which is lowered in compromised bone density sites such as the maxilla as it is categorized as type III & IV bone, so searching for a new innovation and updates in implant material and features is very mandatory. So, the aim of this study was to compare between two implant materials (roxolid and traditional titanium) on the primary and secondary stability of implant retained maxillary overdenture. METHODS: Eighteen completely edentulous patients were selected. All patients received maxillary implant-retained overdentures and lower complete dentures; patients were divided equally into two groups according to the type of implant materials. Group A received a total number of 36 implants made of roxolid material and Group B received a total number of 36 implants made of traditional titanium alloys. Implant stability was assessed using ostell device, the primary implant stability was measured at the day of implant installation however, secondary implant stability was measured after six weeks of implant placement. Paired t-test was used to compare between primary and secondary stability in the same group and an independent t-test was used to compare between the two groups with a significant level < 0.05. RESULTS: Independent t-test revealed a significant difference between the two groups with p -value = 0.0141 regarding primary stability and p-value < 0.001 regarding secondary stability, as roxolid implant group was statistically higher stability than titanium group in both. Paired t- test showed a statistically significant difference in roxolid implant group with p-value = 0.0122 however, there was non-statistically significant difference in titanium group with p-value = 0.636. Mann Whitney test showed a significant difference between the two groups regarding amount of change in stability with p value = 0.191. roxolid implant group showed a higher amount of change in stability than the titanium implant group. CONCLUSION: Within the limitation of this study, it could be concluded that: Roxolid implants showed promising results regarding primary and secondary stability compared to conventional Titanium implants and can be a better alternative in implant retained maxillary overdentures. TRIAL REGISTRATION: Retrospectively NCT06334770 at 26-3-2024.

Antral membrane balloon technique versus Densah bur in crestal sinus lift with simultaneous implant placement: a randomized clinical trial.

BACKGROUND: The posterior maxilla presents challenges for implant insertion because of the poor bone quality as well as the loss of vertical bone height. Indirect transcrestal sinus lift techniques are advised when a few millimeters of additional height are needed. This study aimed to evaluate the clinical and radiographic outcomes of antral membrane balloon technique versus Densah burs for transcrestal maxillary sinus lifting with simultaneous implant placement. MATERIALS AND METHODS: This randomized clinical trial was conducted on 22 patients received 32 dental implants for replacement of missed maxillary posterior teeth after crestal maxillary sinus lifting. The patients were randomly divided into two groups. Group 1, patients underwent crestal sinus floor elevation with simultaneous implant placement using antral membrane balloon technique. Group 2, patients underwent crestal sinus floor elevation with simultaneous implant placement using Densah burs. Patients were evaluated clinically and radiographically using cone beam computed tomography (CBCT) at regular time intervals immediately, 6 months and 12 months after surgery. All clinical and radiographic parameters were statistically analyzed. RESULTS: All dental implants were successful for 12 months of follow up. Regarding implant primary stability, there was a statistical significant difference between the study groups in favor of Densah group (P = 0.004), while there was no significant difference after 6 months (P = 0.07). Radiographically, balloon group showed a statistically significant immediate postoperative vertical bone height (P < 0.0001), and significant reduction in vertical bone height after 6 months (P < 0.0001). Densah group showed significant increase in bone density (P ≤ 0.05). CONCLUSION: Both techniques demonstrated successful clinical and radiographic outcomes for crestal sinus lift. The antral membrane balloon group demonstrated better immediate postoperative vertical bone gain, while Densah burs had higher implant primary stability and bone density. TRIAL REGISTRATION: This study was registered in Clinical-Trials.gov PRS ( https://register. CLINICALTRIALS: gov ) under identification number NCT05922592 on 28/06/2023.