Long-term retrospective studies on the CT-scan, CAD/CAM, one-stage surgery hydroxyapatite-coated subperiosteal implants, including human functional retrievals

L. S. Benjamin

Full text link: https://pubmed.ncbi.nlm.nih.gov/1310663/ 

Long-term retrospective studies on the CT-scan, CAD/CAM, one-stage surgery hydroxyapatite-coated subperiosteal implants, including human functional retrievals

1. Scientific Reference

• Study title: Long-term retrospective studies on the CT-scan, CAD/CAM, one-stage surgery hydroxyapatite-coated subperiosteal implants, including human functional retrievals
• Author: L. S. Benjamin
• PMID: 1310663
• Scientific journal: Not specified in the information provided.
• Year of publication: Not specified in the information provided.
• DOI: Not specified in the information provided.

2. Scientific Background

This publication examines technical developments in subperiosteal implant therapy, with particular emphasis on the integration of computed tomography and computer-aided design and manufacturing (CAD/CAM). The approach described uses multiplanar diagnostic imaging to support implant design according to the underlying osseous anatomy and, importantly, to modify the conventional surgical sequence.

A second aspect addressed by the study is the application of a hydroxyapatite coating to the subperiosteal implant framework. The publication therefore combines anatomical imaging, computer-assisted implant design, surgical protocol modification, and an attempt to enhance the relationship between the implant framework and bone.

Within the context presented by the author, these developments were intended to address some of the anatomical and surgical limitations encountered with the subperiosteal implant procedure. However, the available abstract provides limited information regarding patient characteristics, clinical indications, and the specific anatomical conditions treated.

3. Study Objective

The study investigates the use of subperiosteal implants combining CT-based multiplanar imaging, CAD/CAM technology, a one-stage surgical approach, and hydroxyapatite coating of the implant framework.

Based on the available abstract, the primary objective was to examine how these technical modifications could change the subperiosteal implant procedure, particularly by eliminating an initial surgical stage, extending the technical possibilities of the approach, and promoting a form of bone union around the coated framework. No additional predefined objectives are specified in the information provided.

4. Methodology

The title identifies the work as involving long-term retrospective studies. It also refers to human functional retrievals, indicating that implants or implant components retrieved after functioning in patients were included. However, the available abstract does not describe how these retrieved specimens were examined or what specific outcomes were obtained from their analysis.

The investigated approach combined CT-based multiplanar diagnostic imaging, CAD/CAM technology, one-stage placement of a subperiosteal implant, and hydroxyapatite coating of the implant framework.

The number of patients, number of implants, patient characteristics, exact follow-up period, criteria used to assess outcomes, and methods applied to the retrieved implants are not specified in the information provided. The presence or absence of a control or comparison group is also not reported in the available abstract.

5. Main Results

Two principal findings can be identified from the information provided.

First, the incorporation of multiplanar diagnostic imaging and CAD/CAM technology reportedly made it possible to eliminate the first surgical stage of the subperiosteal implant procedure. According to the author, this development also broadened the capabilities and versatility of the technique.

Second, coating the subperiosteal implant framework with hydroxyapatite was associated with the achievement of bone union. The author interpreted this biological response as a factor with the potential to improve the long-term prognosis of individual cases.

The abstract, however, provides no quantitative data with which to assess the magnitude or consistency of these findings. No implant survival rates, complication rates, statistical analyses, or comparative clinical outcomes are reported. Consequently, the effectiveness and predictability of the protocol cannot be quantified from the information available.

6. Clinical Analysis

The main clinical interest of this publication lies in the combination of three distinct components: CT-based anatomical assessment, CAD/CAM fabrication, and modification of the implant–bone relationship through hydroxyapatite coating.

From a surgical perspective, the reported elimination of the initial operative stage is particularly noteworthy. In the approach described, multiplanar imaging and computer-assisted design appear to have provided sufficient anatomical information to prepare the subperiosteal framework without relying on the earlier surgical sequence discussed by the author. In this respect, the study illustrates a transition toward an implant workflow in which diagnostic imaging and digital design directly influence surgical planning.

The second clinically relevant element concerns the hydroxyapatite-coated framework. The reported bone union was regarded by the author as favorable for long-term prognosis. This finding nevertheless requires cautious interpretation because the available abstract does not describe how bone union was assessed, how consistently it occurred, or whether predefined biological or histological criteria were applied.

These observations should therefore not be interpreted as establishing a definitive therapeutic recommendation. Based on the information available, the publication is more appropriately viewed as clinical and technical evidence documenting the evolution of subperiosteal implant treatment through imaging, CAD/CAM manufacturing, surgical simplification, and surface modification.

7. Clinical Applications

The applications directly supported by the available information primarily concern the planning, design, and placement of subperiosteal implants. The study highlights the use of CT imaging and CAD/CAM technology to account for anatomical morphology during framework design and to enable the procedure to be performed using a one-stage surgical protocol.

The hydroxyapatite coating is also clinically relevant within the specific approach investigated, as the author associates it with the achievement of bone union.

However, the available data do not define precise indications for treatment. The degree of bone atrophy, type of edentulism, patient selection criteria, prosthetic characteristics, and other relevant clinical variables are not provided. Extrapolation of the findings to specific patient populations or broader implant rehabilitation protocols would therefore not be justified on the basis of this abstract alone.

8. Level of Evidence, Limitations, and Transparency

The retrospective nature of the study requires caution when assessing its level of evidence. The information provided does not allow a more precise appraisal of the study design, including whether a control group or direct comparison with another treatment strategy was included.

Several methodological elements required for critical evaluation are absent from the available abstract. These include sample size, number of implants, exact duration of follow-up, outcome criteria, quantitative results, statistical analysis, and complications. These omissions substantially restrict assessment of the robustness and generalizability of the reported findings.

No information regarding funding, manufacturer affiliations, or potential conflicts of interest is included in the material provided. This should be interpreted only as an absence of available disclosure information and not as evidence that no conflicts of interest existed.

9. Key Study Points

• Study type: Long-term retrospective study/studies, according to the title.
• Level of evidence: Limited by the retrospective design; a more precise classification cannot be established from the information provided.
• Population or number of studies analyzed: Not specified in the information provided.
• Number of patients or implants: Not specified in the information provided.
• Follow-up duration: Described as long-term, but no numerical duration is provided.
• Primary outcome: Not explicitly defined in the available abstract.
• Main finding: CT-based multiplanar imaging and CAD/CAM were associated with elimination of the initial surgical stage, while hydroxyapatite coating was associated with reported bone union.
• Scientific conclusion: The author considers these developments capable of extending the possibilities of the subperiosteal implant procedure and potentially improving long-term prognosis.
• Main limitations: Retrospective design and insufficient methodological and quantitative information in the available abstract.

10. Scientific Impact

The scientific relevance of this study lies in its description of CT imaging and CAD/CAM technology as components capable of changing not only the fabrication of a subperiosteal implant but also the surgical workflow itself. The reported ability to eliminate an initial surgical stage illustrates how anatomical imaging and computer-assisted manufacturing could be integrated into the planning and execution of this type of implant rehabilitation.

The study also introduces a biological dimension through hydroxyapatite coating and the reported observation of bone union. In addition, the reference to human functional retrievals in the title suggests an opportunity to examine implants after clinical function, although the abstract does not provide the corresponding analytical methods or findings.

The publication therefore documents a technically relevant development in subperiosteal implant therapy. Nevertheless, the absence of detailed methodology and quantitative outcomes prevents the available evidence from establishing the clinical performance of the protocol with precision.

11. Editorial Conclusion

This retrospective study documents the integration of CT-based imaging and CAD/CAM technology into subperiosteal implant design and placement, together with the use of a hydroxyapatite-coated framework. The reported one-stage surgical approach and bone union are clinically and technically noteworthy. Their significance should nevertheless be interpreted cautiously, since the available abstract does not provide sample size, numerical outcomes, exact follow-up duration, detailed assessment criteria, or complication data. The publication is therefore informative from a technical and historical perspective, while its clinical conclusions remain constrained by the limited data available.