CBCT for Diagnostics, Treatment Planning and Monitoring of Sinus Floor Elevation Procedures

Sinus Bone Graft Stability and Implant Survival Following Transalveolar Sinus Floor Elevation in Severely Atrophic Maxilla: A Retrospective Study With 5-8 Years of Follow-Up

OBJECTIVES

To evaluate the clinical and radiographic results of transalveolar sinus floor elevation (TSFE) with grafting in cases of severely atrophic maxilla.

MATERIALS AND METHODS

A retrospective analysis of clinical and radiographic data was conducted. Between 2015 and 2018, a total of 105 implants were placed in 105 patients over a follow-up period of 5-8 years. Implant failures and endo-sinus bone gain (ESBG) were assessed. Statistical models were established to investigate the potential influencing factors of implant survival and ESBG.

RESULTS

Six patients with six implants were lost, resulting in cumulative survival rates of 94% for both patient- and implant-based analyses. The 8-year cumulative survival rate was significantly lower for residual bone height (RBH) < 4 mm (88%) compared to RBH 4-6 mm (98%). ESBG ≥ 4 mm and ESBG ≥ 6 mm were observed in 89.90% and 58.59% of implant sites, respectively. According to the log-rank Mantel-Cox analysis results, none of the factors examined were significantly related to implant failure, except for RBH (p = 0.038) at baseline. The linear mixed-model regression results showed that the final ESBG was positively correlated with implant insertion site (p = 0.003), implant length (p < 0.001), sinus floor elevation (SFE) methods (p = 0.010), and RBH (p < 0.001).

CONCLUSIONS

Within the limitations of this study, it has been established that TSFE with grafting was a reliable method for implant placement in the posterior atrophic maxilla ridges with RBH ranging from 4 to 6 mm. Nevertheless, caution was advised when considering its application in cases where the initial bone height falls below 4 mm.

Collaboration between otolaryngologists and oral surgeons in maxillary sinus elevation planning

BACKGROUND

The collaboration between otolaryngologists and dental providers is crucial for the planning and execution of maxillary sinus elevation (MSE) procedures, which are integral to successful dental implant placements.

PURPOSE

This article examines the essential role of otolaryngological assessments in identifying potential sinonasal risks that could impact the outcomes of MSE.

MATERIALS AND METHODS

A comprehensive narrative review of existing literature was conducted.

DISCUSSION

The review underscores the importance of thorough preoperative evaluations, including patient history, computed tomography (CT) or cone-beam CT (CBCT) scans, and nasal endoscopy, to mitigate sinonasal health risks. It details various clinical scenarios and patient assessments, emphasizing a systematic approach to diagnosing and managing sinonasal conditions proactively. The discussion reveals that while some sinus conditions may not significantly affect MSE success, conditions impacting mucociliary clearance and sinus drainage are critical risk factors requiring otolaryngological intervention. Additionally, the article introduces a grading system to assist clinicians in identifying patients who would benefit from otolaryngological evaluations prior to MSE.

CONCLUSION

This review highlights the value of interdisciplinary collaboration and standardized protocols in enhancing the predictability and safety of MSE procedures, ultimately improving patient outcomes.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of select 2023 dental literature to briefly touch on several topics of interest to modern restorative dentistry. Each committee member brings discipline-specific expertize in their subject areas that include (in order of appearance here): prosthodontics; periodontics, alveolar bone, and peri-implant tissues; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine, oral and maxillofacial surgery, and oral radiology; and dental caries and cariology. The authors have focused their efforts on presenting information likely to influence the daily dental treatment decisions of the reader with an emphasis on current innovations, new materials and processes, emerging technology, and future trends in dentistry. With the overwhelming volume of literature published daily in dentistry and related disciplines, this review cannot be comprehensive. Instead, its purpose is to inform and update interested readers and provide valuable resource material for those willing to subsequently pursue greater detail on their own. Our intent remains to assist colleagues in navigating the tremendous volume of newly minted information produced annually. Finally, we hope readers find this work helpful in providing evidence-based care to patients seeking healthier and happier lives.

Emergence of artificial intelligence for automating cone-beam computed tomography-derived maxillary sinus imaging tasks. A systematic review

Cone-beam computed tomography (CBCT) imaging of the maxillary sinus is indispensable for implantologists, offering three-dimensional anatomical visualization, morphological variation detection, and abnormality identification, all critical for diagnostics and treatment planning in digital implant workflows. The following systematic review presented the current evidence pertaining to the use of artificial intelligence (AI) for CBCT-derived maxillary sinus imaging tasks. An electronic search was conducted on PubMed, Web of Science, and Cochrane up until January 2024. Based on the eligibility criteria, 14 articles were included that reported on the use of AI for the automation of CBCT-derived maxillary sinus assessment tasks. The QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2) tool was used to evaluate the risk of bias and applicability concerns. The AI models used were designed to automate tasks such as segmentation, classification, and prediction. Most studies related to automated maxillary sinus segmentation demonstrated high performance. In terms of classification tasks, the highest accuracy was observed for diagnosing sinusitis (99.7%), whereas the lowest accuracy was detected for classifying abnormalities such as fungal balls and chronic rhinosinusitis (83.0%). Regarding implant treatment planning, the classification of automated surgical plans for maxillary sinus floor augmentation based on residual bone height showed high accuracy (97%). Additionally, AI demonstrated high performance in predicting gender and sinus volume. In conclusion, although AI shows promising potential in automating maxillary sinus imaging tasks which could be useful for diagnostic and planning tasks in implantology, there is a need for more diverse datasets to improve the generalizability and clinical relevance of AI models. Future studies are suggested to focus on expanding the datasets, making the AI model's source available, and adhering to standardized AI reporting guidelines.

Anatomical Factors Affecting the Complexity of Maxillary Sinus Augmentation in Saudi Patients: A Cone Beam Computed Tomography (CBCT) Study

AIM

This study aims to evaluate the anatomical variations of the maxillary sinus and determine the difficulty score of maxillary sinus augmentation (MSA) in Saudi patients seeking dental implant rehabilitation of the posterior maxilla using cone beam computed tomography (CBCT).

METHODOLOGY

CBCT records of dental patients seeking treatment at a University Dental Teaching Hospital between 2019 and 2023 were retrospectively analyzed. Measurements were obtained from CBCT images, including membrane thickness, sinus width, buccal bone thickness, presence of maxillary sinus septa, residual alveolar ridge height, angle of the buccolingual sinus wall, and the presence of the alveolar antral artery (AAA). The difficulty score for MSA was determined based on these anatomical factors.

RESULTS

A total of 107 maxillary sinuses in 86 subjects were evaluated. The average membrane thickness was 2.23 mm, with males showing significantly higher thickness than females. Sinus septa were found in 54 (50.5%) sinuses, with 18 (17%) of sinuses having interfering septa. Twenty-three (21.5%) sinuses had a residual alveolar ridge height of less than 4 mm. The average angle of the buccolingual sinus wall was 79.39°, indicating a high prevalence of wide-shaped sinuses. The average sinus width was 14.09 mm, with 55 sinuses (51.4%) less than 15 mm. The average buccal bone thickness was 1.07 mm, in 29 (27%) sinuses, the thickness was more than 2 mm. AAA was visualized in 60 (56%) of sinuses, with 45 (42%) of sinuses having AAA interfering with the MSA window.

CONCLUSIONS

In this study, most sinuses were classified as simple or moderate difficulty, with higher membrane thickness, presence of septa, and AAA being the significant risk factors for complications. These findings provide valuable insights for implant surgeons in Saudi patients seeking dental implant rehabilitation of the posterior maxilla, enabling them to anticipate and minimize potential complications during MSA procedures.

Digital planning and bone regenerative technologies: A narrative review

OBJECTIVES

The aim of this narrative review was to explore the application of digital technologies (DT) for the simplification and improvement of bone augmentation procedures in advanced implant dentistry.

MATERIAL AND METHODS

A search on electronic databases was performed to identify systematic reviews, meta-analyses, randomized and non-randomized controlled trials, prospective/retrospective case series, and case reports related to the application of DT in advanced implant dentistry.

RESULTS

Seventy-nine articles were included. Potential fields of application of DT are the following: 1) the use of intra-oral scanners for the definition of soft tissue profile and the residual dentition; 2) the use of dental lab CAD (computer-aided design) software to create a digital wax-up replicating the ideal ridge and tooth morphology; 3) the matching of STL (Standard Triangulation Language) files with DICOM (DIgital COmmunication in Medicine) files from CBCTs with a dedicated software; 4) the production of stereolithographic 3D models reproducing the jaws and the bone defects; 5) the creation of surgical templates to guide implant placement and augmentation procedures; 6) the production of customized meshes for bone regeneration; and 7) the use of static or dynamic computer-aided implant placement.

CONCLUSIONS

Results from this narrative review seem to demonstrate that the use of a partially or fully digital workflow can be successfully used also in advanced implant dentistry. However, the number of studies (in particular RCTs) focused on the use of a fully digital workflow in advanced implant dentistry is still limited and more studies are needed to properly evaluate the potentials of DT.

Autologous leucocyte and platelet rich in fibrin (L-PRF) - is it a competitive solution for bone augmentation in maxillary sinus lift? A 6-month radiological comparison between xenografts and L-PRF

Maxillary lateral sinus floor elevation, or external sinus lift, is a widespread surgical intervention in the dental field. Insertion of implants in the posterior region of the maxilla often requires reconstruction of the remaining native bone that has insufficient volume.

Background and aims

Much of the research published involves using artificial products, like xenografts and resorbable collagen membranes, after a prior Cone Beam Computer Tomography (CBCT) investigation. Nowadays, more accessible access, less financial costs, a biological approach, and faster healing are objectives that surround this procedure. Leucocytes and platelets rich in Fibrin (L-PRF) are a natural component with a high concentration of growth factors. Due to its regenerative properties and lack of complications, it is used in several medical fields, like orthopedics, dermatology, and oral surgery. This retrospective study aims to compare results in bone height and volume obtained through external sinus lift, either by using xenografts or autologous plasma rich in fibrin, by evaluating the quantity of new bone formation from a radiological point of view.

Methods

Fifty-eight Caucasian patients were included in this retrospective study; 48 were submitted to xenograft procedure, and 10 were selected for L-PRF grafting material with simultaneous implant placement. Lack of clinical and histological studies performed on patients with L-PRF surgeries limited us in choosing a larger group for the radiological analysis. CBCT evaluation was performed before surgery and 6 months after. All patients selected for the study presented good general and oral health, acute oral and sinus infections excluded; smoking and periodontal disease were also criteria of exclusion. Two operators performed the measurements in pre-established landmarks in different time frames. The two independent groups were compared with the Wilcoxon rank-sum test for quantitative data. Qualitative characteristics were described as counts and percentages. All analyses were performed in an R environment for statistical computing and graphics.

Results

Mean bone height gain in the xenograft group in the regions was as follows: 7.44 for the anterior landmark, 12.14 for the median and 8.28 for the distal. The mean group height gained for the L-PRF group was 0.1 anteriorly, -0.18 for the median measurement, and 0.23 distally. We obtained excellent overall reliability for all the height measurements between the two operators.

Conclusions

Further studies must be conducted to establish new sets of surgical protocols in case L-PRF alone is found to be a reliable, stable, biological alternative to the well-documented xenografts in external sinus lifts. Radiological results, although promising, must be further applied in long term clinical survival of the implants in the grafted sites. Also, studies combining L-PRF in conjunction with xenograft might bring improved clinical results in terms of reduced postoperative complications and accelerated healing.

Radiological Study on the Evolution of the Biomaterial's Image (Shape, Density, Vertical Dimensions) after the Lateral Sinus Lift

The aim of this study is to evaluate the long-term changes of sinus lift material. Materials and methods: We included a total number of 35 patients (20 men and 15 women), between 32 and 80 years old, evaluated on a timeframe of up to 11.6 years. Diverse biomaterials were used (allograft, xenograft, alloplastic, combinations of them), with autologous bone in some cases. Results: The appearance of the top plane of the bone over time took a large dome shape (36% of cases), a linear shape (32% of cases), an irregular shape (23% of cases), or had micro domes above the implants (7%). No significant differences were found between the groups regarding age. The radiological density of the biomaterial tended to equalize that of the native bone. The final vertical dimensions seemed to be independent of the initial native bone height but seemed to be correlated with the amount of applied biomaterial. For the study group, the biomaterial contracted on average by 10% for the maximum height (H max) and 20% for the minimum height (H min), which can explain the tendency of the upper border of the biomaterial to curve. The annual H max contraction ranged from -0.09 to +0.18 with a mean value of 2.67% (SD = 0.04, CI: [0.011, 0.041]). The median value was 1.8%. The annual H min contraction ranged from -0.24 to +0.24, with a mean value of 4.33% (SD = 0.07, CI: [0.021, 0.065]). The median value was 3.59%. There were no statistically significant gender differences (Mann-Whitney U, p = 0.483, p = 0.642). The additional application of biomaterial together with the implants seemed to have a beneficial effect on the final vertical dimension of the bio-transformed material.