Application of sticky bone combined with concentrated growth factor (CGF) for horizontal alveolar ridge augmentation of anterior teeth: a randomized controlled clinical study.

OBJECTIVE: This study was designed to estimate the effect of sticky bone combined with concentrated growth factor (CGF) on anterior alveolar horizontal augmentation during implantation. METHODS: Twenty-eight patients were randomly assigned to either the test group (Group 1, n = 14) or the control group (Group 2, n = 14). Patients in Group 1 and Group 2 underwent GBR using sticky bone combined with CGF and bone powders mixed with saline, respectively. On postoperative Day 7, the patients completed the visual analogue scale (VAS). Three-dimensional models of maxillary alveolar bone were reconstructed from CBCT data at different periods, and the bone volume conversion rate was calculated with the assistance of a measurement marker guide. Labial bone thickness before and after trauma closure and bone density at six months postoperatively were also measured. RESULTS: The mean bone volume conversion rate for Group 1 (72.09 ± 12.18%) was greater than that for Group 2 (57.47 ± 9.62%, P = 0.002). The VAS score was lower for Group 1 than for Group 2 (P = 0.032). At six months postoperatively, greater bone density was found in patients in Group 1 than in those in Group 2, although the difference was not statistically significant (P > 0.05). The change in the thickness of the labial bone graft material in Group 1 was smaller than that in Group 2 (P = 0.025). CONCLUSION: Sticky bone combined with CGF was able to achieve better bone augmentation than conventional GBR. With excellent mechanical properties and the capacity to release growth factors, sticky bone is an ideal material for bone grafting. TRIAL REGISTRATION: The study was registered at the Chinese Clinical Trial Registry on 10/04/2022 (Identification number: ChiCTR2200058500).

Quality of life in oncologic patients after maxillectomy operations: clinical case series on different rehabilitation protocols.

OBJECTIVE: The study's purpose was to compare the quality of life (QoL) in oncologic patients treated with different rehabilitation protocols following maxillary tumor resections. PATIENTS AND METHODS: The patients were divided into three groups. Group A: 18 Patients with maxillary obturator prosthesis. Group B: 17 Patients with simultaneous autologous tissue reconstruction. Group C: 12 Patients with prosthesis on zygomatic implants. The post-operative QoL was compared using standard questionnaires, investigating items like pain, mood, social relations, and specific functions that could potentially compromise the post-operative QoL. A secondary analysis compared reconstructed vs. non-reconstructed patients. RESULTS: Most questionnaire items did not show significant differences among groups. Statistically significant outcomes were found in two parameters (social contact and sexuality), in which patients treated with zygomatic implants had the best satisfaction, and patients with obturator prostheses showed the lowest satisfaction. Patients belonging to the non-reconstructed group showed better moods than those in the reconstructed group, while taste problem complaints and pain were lower in the reconstructed group. CONCLUSIONS: Although the type of reconstruction procedure depends on the type of maxillectomy to be performed and on the general health situation of each patient, the impact of the rehabilitation protocol on the patients' QoL should be accounted for when planning the treatment.

Implant Placement When an Impacted Tooth and Supernumerary Teeth Are Present in the Maxilla.

The presence of impacted and/or supernumerary teeth in the maxillary anterior region can cause complications when attempting to perform restorations with implants. Extracting these structures can lead to adverse issues related to the adjacent dentition and require osseous grafting to provide a base to house the planned implant, but such an approach increases treatment time and cost. In this case report, a patient presented with an impacted permanent canine oriented on the horizontal plane with several supernumerary teeth coronal to the impacted canine. CBCT analysis revealed a very thin buccal plate over the impacted supernumerary teeth. The proposed treatment followed the principles of partial extraction therapy (PET) whereby the impacted structures were treated like bone, and implants were placed in contact with them or through them to achieve the desired osseointegration and provide long-term survival of the restored implants.

Clinical efficacy of intraoral ultrasonography versus transgingival probing for measurement of gingival thickness in different gingival biotypes: a clinical trial.

BACKGROUND: Transgingival probing is conventionally used for gingival thickness (GT) measurement. However, invasiveness is a major drawback of transgingival probing. Thus, researchers have been in search of alternative methods for measurement of GT. This study compared the clinical efficacy of intraoral ultrasonography and transgingival probing for measurement of GT in different biotypes. MATERIALS AND METHODS: This clinical trial was conducted on 34 patients requiring crown lengthening surgery. GT was measured at 40 points with 2- and 4-mm distances from the free gingival margin (FGM) of anterior and premolar teeth of both jaws in each patient by an intraoral ultrasound probe. For measurement of GT by the transgingival probing method, infiltration anesthesia was induced, and a #25 finger spreader (25 mm) was vertically inserted into the soft tissue until contacting bone. The inserted length was measured by a digital caliper with 0.01 mm accuracy. All measurements were made by an operator with high reliability under the supervision of a radiologist. Data were analyzed by t-test, Power and Effect Size formula, and intraclass correlation coefficient (ICC). RESULTS: The two methods were significantly different in measurement of GT in both thick and thin biotypes at 2- and 4-mm distances (P < 0.001). The two methods had a significant difference in both the mandible (P < 0.001) and maxilla (P < 0.001) and in both the anterior (P < 0.003) and premolar (P < 0.003) regions. Although the difference was statistically significant in t-tests, the power and effect formula proved it to be clinically insignificant. Also, the ICC of the two methods revealed excellent agreement. CONCLUSION: The results showed optimal agreement of ultrasound and transgingival probing for measurement of GT. TRIAL REGISTRATION: The study was approved by the ethics committee of Shahid Beheshti University of Medical Sciences on 2021-12-28 (IR.SBMU.DRC.REC.1400.138) and registered in the Iranian Registry of Clinical Trials on 2022-03-14 (IRCT20211229053566N1).

Correlation Between Acquisition of Dental Implant Stability and Hounsfield Units at Dental Implant Placement.

Alveolar bone quality at the implantation site affects the initial stability of dental implant treatment. However, the relationship between bone quality and osseointegration has yet to be evaluated. Herein, we aimed to investigate the effect of bone quality on dental implant stability in osseointegration formation changes. Patients underwent computed tomography imaging before dental implantation at the posterior. Hounsfield units were measured at the platform, middle, and tip sites. Implant stability was measured using resonance frequency analysis immediately and at 3 months postoperatively, in which the difference in implant stability quotients (ISQ) was defined as the change between primary and secondary fixation. In multiple regression analysis, the dependent variable was the change between the immediate and secondary fixations. We included 81 implants that conformed to the criteria. Primary fixation yielded the following results: R2 = 0.117, F = 2.529, and P = .047. The difference between the maxilla and mandible of the implantation site (P = .02) and the platform-site Hounsfield units (P = .019) were identified as significant factors. The following results were obtained regarding the change between the immediate and secondary fixation: R2 = 0.714, F = 40.964, and P < .001. The difference between diameter (P = .008) and the immediate ISQ (P < .001) were identified as significant factors. Overall, the bone quality of the implantation site affected initial fixation; however, it had limited effect on secondary fixation. Our findings clarified the period where bone quality affects dental implant treatment and is expected to advance dental implant treatment.

Biomechanical behavior of implant retained prostheses in the posterior maxilla using different materials: a finite element study.

BACKGROUND: The aim of this study is to evaluate the biomechanical behavior of the mesial and distal off-axial extensions of implant-retained prostheses in the posterior maxilla with different prosthetic materials using finite element analysis (FEA). METHODS: Three dimensional (3D) finite element models with three implant configurations and prosthetic designs (fixed-fixed, mesial cantilever, and distal cantilever) were designed and modelled depending upon cone beam computed tomography (CBCT) images of an intact maxilla of an anonymous patient. Implant prostheses with two materials; Monolithic zirconia (Zr) and polyetherketoneketone (PEKK) were also modeled .The 3D modeling software Mimics Innovation Suite (Mimics 14.0 / 3-matic 7.01; Materialise, Leuven, Belgium) was used. All the models were imported into the FE package Marc/Mentat (ver. 2015; MSC Software, Los Angeles, Calif). Then, individual models were subjected to separate axial loads of 300 N. Von mises stress values were computed for the prostheses, implants, and bone under axial loading. RESULTS: The highest von Mises stresses in implant (111.6 MPa) and bone (100.0 MPa) were recorded in distal cantilever model with PEKK material, while the lowest values in implant (48.9 MPa) and bone (19.6 MPa) were displayed in fixed fixed model with zirconia material. The distal cantilever model with zirconia material yielded the most elevated levels of von Mises stresses within the prosthesis (105 MPa), while the least stresses in prosthesis (35.4 MPa) were recorded in fixed fixed models with PEKK material. CONCLUSIONS: In the light of this study, the combination of fixed fixed implant prosthesis without cantilever using a rigid zirconia material exhibits better biomechanical behavior and stress distribution around bone and implants. As a prosthetic material, low elastic modulus PEKK transmitted more stress to implants and surrounding bone especially with distal cantilever.

Comparison of different maxillary advancement protocols in patients with unilateral cleft lip and palate: a finite element analysis.

OBJECTIVES: The aim of this study was to evaluate the stress distributions and possible amount of movement in the maxillofacial region resulting from different maxillary advancement protocols in patients with unilateral cleft lip and palate. MATERIALS AND METHODS: A unilateral cleft lip and palate model (CLP model) with Goslon score 4 was created for finite element analysis. Three different protocols were compared: Group 1: usage of a face mask with elastics placed at a 30? angle to the occlusal plane over a conventional acrylic plate; Group 2: usage of a face mask with elastics placed at a 30? angle to the occlusal plane over miniplates placed in the infrazygomatic crest region; Group 3: usage of elastic from the menton plate placed in the mandible to the infrazygomatic plates in the maxilla. RESULTS: Dental effects were greater in the maxillary protraction protocol with a face mask over a conventional acrylic plate (Von Misses Stress Values; Group 1?=?cleft side:0.076, non-cleft side:0.077; Group 2?=?cleft side:0.004, non-cleft side: 0.003; Group 3?=?cleft side:0.0025; non-cleft side:0.0015), whereas skeletal effects were greater in maxillary protraction protocols with face mask using skeletal anchorage (Von Misses Stress Values; Group 1:0.008; Group 2:0.02; Group 3:0.0025). The maximum amount of counterclockwise rotation of the maxilla as a result of protraction was observed in traditional acrylic plate face mask protocol, and the minimum amount was observed by using elastics between infrazygomatic plates and menton plate. CONCLUSIONS: In individuals with unilateral cleft lip and palate with Goslon score 4, it was observed that the skeletally anchored face mask caused more skeletal impact and displacement than both the traditional acrylic plate face mask model and the pure skeletally supported maxillary protraction model. CLINICAL RELEVANCE: When planning maxillary protraction treatment in patients with cleft lip and palate, it should be considered that more movement in the sagittal plane might be expected on the cleft side than the non-cleft side, and miniplate and screws on the cleft side are exposed to more stress when using infrazygomatic plates as skeletal anchorage.

Volumetric Analysis of Peri-implant Tissue Change Over Time: Validating an Innovative 3D Method.

PURPOSE: To validate an innovative 3D volumetric method of evaluating tissue changes proposed by Lee et al in 2020 by comparing the results of this method-in which the scanned peri-implant surfaces were transformed, visualized, and analyzed as 3D objects-to the results reported by an existing method based on calculation of the mean distance between measured surfaces. The null hypothesis was that there was no statistically significant difference between the two methods. Additionally, the present study evaluated peri-implant tissue changes 5 years after single implant placement in the esthetic zone. MATERIALS AND METHODS: Both methods were applied to 11 oral implant site casts (6 maxillary central incisor sites, 5 maxillary lateral incisor sites) taken from 11 patients at crown placement and at follow-up examinations 5 years later. The methods are based on digital workflows in which the reference and 5-year casts are scanned and the resulting STL files are superimposed and analyzed for three regions of interest (mesial papilla, central area, and distal papilla). The volumetric changes reported by the Lee et al method and the mean distance method were calculated and compared using the Spearman rank correlation coefficient (P < .01) and the Wilcoxon signed-rank test (P < .05). RESULTS: The correlation between the two sets of measurements was very high (Spearman rank correlation coefficient = 0.885). The new volumetric method indicated a mean volume loss of 2.82 mm3 (SD: 5.06), while the method based on the measurement of mean distance showed a mean volume loss of 2.92 mm3 (SD: 4.43; Wilcoxon signed-rank test result: P = .77). No statistically significant difference was found. The two methods gave equivalent results, and the null hypothesis was accepted. CONCLUSIONS: The new volumetric method was validated and can be considered a trustworthy tool.

[Review of clinical effects of disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation in 10 years].

PURPOSE: To analyze the bone remodeling around the implant 10 years after disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation and to investigate the influence of different factors on implant retention. METHODS: The clinical and imaging data of patients undergoing DSR-based sinus floor elevation with simultaneous implantation were collected from the Department of Dental Implantology, Affiliated Hospital of Qingdao University from January 2008 to December 2011. Panoramic film and CBCT were used to measure the changes of bone mass around implant in different periods. Kaplan-Meier and Log-rank tests were used to analyze the effects of different factors on implant retention with SPSS 26.0 software package. RESULTS: The study included 98 patients with a total of 128 implants. During the follow-up of 0-168 months, 7 implants failed, and the remaining formed good osseointegration and functioned, with a 10-year cumulative retention rate of 94.53%. The height of bone formation was (0.29±0.15) mm at the top and (2.74±0.66) mm in the sinus of 75 implant sites with complete imaging data obtained ten years after surgery. Kaplan-Meier and Log-rank tests showed that 8 factors including initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis had significant effects on implant retention. CONCLUSIONS: The DSR-based internal sinus floor elevation with implantation is a reliable and stable bone augmentation operation for vertical bone defect in maxillary posterior region, with a 10-year cumulative retention rate of no less than 94%. Initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis are the important factors affecting the long-term retention rate of implants.

Immediate single-tooth replacement with acellular dermal matrix allogeneic bone and ossifying collagen scaffold: A case series.

The pursuit of predictable implant success in the aesthetic zone continues as technology develops. Creating stable marginal bone and an optimal peri-implant mucosal environment is the foundation for a long-term healthy and aesthetic implant treatment outcome. Tissue stability is dependent on multiple factors, including the regenerative materials used to create the peri-implant supporting tissues and maintain the tissue volume. The present study aims to describe a technique that combines a flapless approach to extract hopeless teeth in the aesthetic zone and implant insertion using an acellular dermal matrix placed to contain the coronal aspect of an innovative ossifying collagen scaffold designed to promote neoformation of vital native bone. This technique combines a minimally invasive approach with the application of a novel biomaterial that offers stable augmentation of the gingival thickness as well as bone fill in the facial gap, the space between the implant and the buccal plate, to ensure predictable aesthetic results. A collection of cases are presented to demonstrate the surgical technique and the situation over a follow-up period of 22 months. Pre- and post-treatment CBCT imaging were utilised to quantify the stability or changes noted in the alveolar bone, and pre-and post-treatment intraoral scanning were used for the same purpose in the peri-implant phenotype. This case series presents stable and aesthetic clinical outcomes evaluated through digital assessment.

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

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

Immediate implant placement in the anterior mandible: a cone beam computed tomography study.

BACKGROUND: The placement of implants into the alveolar socket right after tooth extraction is called immediate implant placement (IIP). This approach has its particularities depending on which region of the jaws is involved. The anterior mandible region is peculiar due to the presence of mandibular incisors, which have the shortest roots among all permanent teeth. PURPOSE: This study aimed to investigate the factors that could be associated with the risk of either cortical bone wall perforation or invasion of the 2 mm secure distance from the surrounding anatomical structures (defined as unsafe implant placement), with IIP in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study. MATERIALS AND METHODS: CBCT exams from 239 eligible subjects were investigated. Implants were virtually placed in two distinct positions: prosthetically-driven (along the long axis of the existing tooth) and bone-driven position (according to the available bone and with regard to nearby anatomical structures). Correlation between several variables was tested, and binary logistic regression analysis in order to assess of the possible associations between covariates and unsafe placement was performed. RESULTS: Safe placing implants was significantly higher for the bone-driven in comparison to the prosthetically-driven position (22.2% vs. 3.3%, respectively), and the 2-mm secure distance from anatomical structures was not possible to respect in the majority of cases (77.6% vs. 82.9%, respectively). Covariates associated with a higher risk of unsafe placement were tooth region (CI in relation to IL and CA), decrease of labial concavity angle (LCA), decrease of mandible basal bone height (MBBH), and decrease in mandibular bone thickness at the tooth apex level (MBT0). CONCLUSION: The possibility of safely placing immediate implants in the anterior mandible is significantly higher for bone-driven than in prosthetically driven position. Presurgical virtual planning with CBCT is a great tool for minimizing the risk of implant unsafe placement with regards to the anatomical conditions in the mandible.

Anterior endoscopic sublabial transmaxillary access to middle cranial base lesions.

BACKGROUND: Anterior endoscopic access to middle cranial base lesions becomes feasible in the presence of infratemporal fossa (ITF) involvement. Various approaches, including endoscopic endonasal, transoral sublabial, and transorbital methods, have been described for accessing the ITF through a transmaxillary corridor. Among these approaches, endonasal access is the most commonly preferred, while the transorbital approach is a novel technique gaining popularity. The transoral sublabial approach is considered suitable for selected lesions. METHODS: Patients who underwent the anterior endoscopic transoral/sublabial transmaxillary approach to middle cranial base lesions at a single institute from 2016 to 2023 were included in this retrospective study. Malignant lesions were excluded from the study. The sublabial approach was exclusively performed in all cases, with the exception of one patient who required a combined approach. RESULTS: The anterior endoscopic transoral sublabial transmaxillary approach to the infratemporal fossa, upper parapharyngeal space, and middle cranial fossa was performed on 14 patients. The underlying conditions for these patients were as follows: trigeminal schwannomas (n = 8), meningiomas (n = 2), juvenile nasopharyngeal angiofibroma, osteochondroma, arachnoid cyst and encephalocele (n = 1 each). Gross total resection was achieved in 11 cases. The most common complication was numbness in the territory of the maxillary and mandibular nerves (n = 4). Two patients needed endoscopic maxillary antrostomy for persistent suppuration. No wound problems or CSF rhinorrhea occurred. The average follow-up time was 26.6 months. CONCLUSION: The endoscopic sublabial transmaxillary approach provides direct access to the infratemporal fossa and middle cranial base, enhancing the surgical range of maneuverability while sparing the sinonasal cavity. This procedure is safe, less invasive, and could be used as an efficient corridor for the resection of selected infratemporal fossa lesions with or without extension to the middle cranial base and parapharyngeal space.

Can different osteotomies have an influence on surgically assisted rapid maxillary expansion? A systematic review.

The purpose of this study was to systematically review the randomized and non-randomized clinical trials (RCT; nRCT) concerning the different available osteotomies for surgically assisted rapid maxillary expansion (SARME): pterygomaxillary disjunction (SARME + PD vs SARME-PD) and segmental Le Fort I osteotomy (2-piece vs 3-piece). Outcomes focused on skeletal, dental, upper airway changes, complications, and relapse. Two authors investigated five databases (PubMed, Cochrane Library, Google Scholar, Scopus, Web of Science) until August 2023. The Cochrane Collaboration Tool and the Newcastle-Ottawa scale were used for the quality assessment of the included RCTs and nRCTs, respectively. A total of 554 articles were retrieved and after duplicates removing and full-text reading, 40 studies were included. Two RCTs showed a low risk of bias, one an unclear risk and one a high risk. Among the non-RCTs, 15 studies showed a good quality, while 21 exhibited a fair quality score. SARME + PD resulted in more homogeneous posterior bone expansion, with minimal dental effects. No difference between 2-piece and 3-piece in asymmetric expansion was observed, although 3SO showed 1-2 mm of more transverse increase. The oropharynx minimum cross-sectional area, the nasopharynx and the oropharynx volume were greater in SARME + PD. Both dental and bone relapse can occur but no differences between the groups were observed. All osteotomies guaranteed a correction of transverse maxillary deficiency. Lower side effects were described in SARME + PD. Two-piece and 3-piece segmental Le Fort I osteotomies did not show any differences in the symmetry and amount of expansion.

An in vitro study in separating tensile loads during maxillo-mandibular fixation using wire and/or elastics.

Intermaxillary fixation (IMF) or maxillo-mandibular fixation (MMF) is a fundamental process in stabilizing the maxilla and mandible through dental maximum intercuspation (MIP) during the management of trauma, orthognathic surgery, and reconstruction. Despite the availability of several techniques in achieving adequate maxillo-mandibular fixation, concerns have been raised regarding the sufficiency of using only latex elastics to counter displacing forces during reduction and fixation. To address this, an in vitro study was conducted to compare the efficacy of three maxillo-mandibular fixation methods: wire, elastics, and a combination of both. Custom-made models simulating dental arches were used, and a vertical separation of up to 1 mm was applied at a loading rate of 1 mm/minute using an Instron 5566 Universal Testing Machine. Tensile loads were recorded at 0.5 and 1 mm vertical separation, with each process repeated 10 times in each sample group. The average peak tensile load was then calculated. Statistical analysis using one-way ANOVA at a significance level of p<0.05 revealed significant differences between all three subject groups. The outcomes of this in vitro study suggest that the combination technique (using both wire and elastics) outperformed the individual methods in achieving robust maxillo-mandibular fixation. This positions the combination technique as the most effective among the evaluated fixation methods.

Comprehensive analysis of lateral nasal wall anatomy to optimize the osteotomy in different skeletal patterns.

PURPOSE: Variations in nasal wall anatomy are crucial in patients with dentofacial deformities undergoing Le Fort I osteotomy. These structural variations heighten the potential for complications during surgical procedures. Hence, the study focused on evaluating the differences in the lateral nasal wall anatomy across different skeletal Classes. METHODS: This study evaluated 86 patients aged 18-43 years with different skeletal Classes. In the axial images acquired from coronal sections, two angulations and the linear distances of the lateral nasal wall were measured in Class I, II, and III patients. The measurement between the piriform opening and the most anterior point of the greater palatine foramen was evaluated in three parts regarding the osteotomy line. Differences between the skeletal patterns were analyzed using an independent sample t-test and Mann-Whitney U test with a significance level of 0.05. The intra-class correlation coefficient was calculated for inter-observer and intra-observer agreement. RESULTS: There was a statistically significant difference between Class I and Class II subjects regarding the anterior lateral nasal wall (p = 0.011) and anterior nasal thickness (a) (0.004). There was a significant difference between Class I and Class III patients regarding anterior nasal thickness (a) (p < 0.001) and total lateral nasal wall length (p < 0.001). CONCLUSION: For instance, the measurements of Class III and Class II patients were relatively different from those of the Class I patients. Therefore, preoperative Cone-Beam Computed Tomographic analysis should be performed for each patient prior to Le Fort I osteotomy to ensure that the procedure is performed safely.

Clinical outcomes of narrow- and regular-diameter implants with bone augmentation in the anterior maxilla: a systematic review and meta-analysis.

OBJECTIVES: To evaluate the clinical outcomes of narrow-diameter implants (NDIs) and regular-diameter implants (RDIs) with bone augmentation in the anterior maxilla, with implant survival rate (ISR) as the primary outcome. Additionally, secondary outcomes such as peri-implant marginal bone loss (MBL), pocket probing depth (PPD), mechanical complications, and biological complications were also considered. MATERIALS AND METHODS: A thorough literature search was performed to identify randomized controlled trials and cohort studies comparing outcomes of NDIs and RDIs with bone augmentation in the anterior maxilla published up to February 2024. Only studies with a minimum follow-up period of 12 months were selected for analysis. Meta-analysis was performed if at least two articles with similar characteristics were available. RESULTS: Of the 288 articles initially considered, 5 were included in the analysis, involving 282 NDIs and 100 RDIs. At the 36-month follow-up, no statistically significant differences in ISR, which ranged 93.8-100% for NDIs and were 100% for RDIs, were observed between the two groups (relative risk, 0.989; 95% confidence interval, 0.839-1.165; p = 0.896). Similarly, MBL and PPD did not differ significantly between the two groups. Soft tissue dehiscence was the most common complication found in RDIs. CONCLUSION: The results indicate that NDIs yield clinical outcomes similar to those of RDIs with bone augmentation in the anterior maxilla over a 36-month follow-up period. CLINICAL RELEVANCE: Considering the similar clinical outcomes, the shortened treatment duration and more rapid esthetic improvement associated with NDIs may render them preferrable to RDIs with bone augmentation, particularly in this esthetic zone.

Clinical challenges of biomechanical performance of narrow-diameter implants in maxillary posterior teeth in aging patients: A finite element analysis.

This study evaluated the biomechanical performance of narrow-diameter implant (NDI) treatment in atrophic maxillary posterior teeth in aging patients by finite element analysis. The upper left posterior bone segment with first and second premolar teeth missing obtained from a patient's cone beam computed tomography data was simulated with cortical bone thicknesses of 0.5 and 1.0 mm. Three model groups were analyzed. The Regimen group had NDIs of 3.3 × 10 mm in length with non-splinted crowns. Experimental-1 group had NDIs of 3.0 × 10 mm in length with non-splinted crowns and Experimental-2 group had NDIs of 3.0 × 10 mm in length with splinted crowns. The applied load was 56.9 N in three directions: axial (along the implant axis), oblique at 30° (30° to the bucco-palatal plane compared to the vertical axis of the tooth), and lateral load at 90° (90° in the bucco-palatal plane compared to the vertical axis of the tooth). The results of the von Mises stress on the implant fixture, the elastic strain, and principal value of stress on the crestal marginal bone were analyzed. The axial load direction was comparable in the von Mises stress values in all groups, which indicated it was not necessary to use splinted crowns. The elastic strain values in the axial and oblique directions were within the limits of Frost's mechanostat theory. The principal value of stress in all groups were under the threshold of the compressive stress and tensile strength of cortical bone. In the oblique and lateral directions, the splinted crown showed better results for both the von Mises stress, elastic strain, and principal value of stress than the non-splinted crown. In conclusion, category 2 NDIs can be used in the upper premolar region of aging patients in the case of insufficient bone for category 3 NDI restorations.