Intraoperative application of three-dimensional printed guides in total hip arthroplasty: A systematic review

BACKGROUND Acetabular component positioning in total hip arthroplasty(THA)is of key importance to ensure satisfactory post-operative outcomes and to minimize the risk of complications.The majority of acetabular components are aligned freehand,without the use of navigation methods.Patient specific instruments(PSI)and three-dimensional(3D)printing of THA placement guides are increasingly used in primary THA to ensure optimal positioning.AIM To summarize the literature on 3D printing in THA and how they improve acetabular component alignment.METHODS PubMed was used to identify and access scientific studies reporting on different 3D printing methods used in THA.Eight studies with 236 hips in 228 patients were included.The studies could be divided into two main categories;3D printed models and 3D printed guides.RESULTS 3D printing in THA helped improve preoperative cup size planning and post-operative Harris hip scores between intervention and control groups(P=0.019,P=0.009).Otherwise,outcome measures were heterogeneous and thus difficult to compare.The overarching consensus between the studies is that the use of 3D guidance tools can assist in improving THA cup positioning and reduce the need for revision THA and the associated costs.CONCLUSION The implementation of 3D printing and PSI for primary THA can significantly improve the positioning accuracy of the acetabular cup component and reduce the number of complications caused by malpositioning.

Application of digital positioning guide plates for the surgical extraction of multiple impacted supernumerary teeth:A case report and review of literature

BACKGROUND An extra tooth in the normal tooth sequence in any region of the dental arch is regarded as a supernumerary tooth(SNT).Due to the large variation in location and morphology,the extraction of impacted SNTs is an extensive and complex procedure with high risks of several complications.This report presents a rare case of seven impacted SNTs in the bilateral upper and lower arch that were successfully extracted with the use of digital positioning guide plates.CASE SUMMARY In January 2022,a 21-year-old male was referred to our department with a chief complaint of pain in relation to tooth#36.Clinical examination showed a deep carious lesion with pulpal involvement in tooth#36 and lingual swelling of the bilateral mandibular posterior area.Radiographic examination revealed seven deeply impacted SNTs in the bilateral posterior area and bilateral impacted mandibular third molars.Based on these findings,the patient was diagnosed with bilateral,multiple impacted SNTs and tooth#36 chronic pulpitis.A root canal treatment and an all-ceramic crown restoration for tooth#36 were performed.An individualized digital positioning guide plate was designed by computer-aided design/computer-aided manufacturing technology and cone-beam computed tomography for extraction of the impacted SNTs.During the operation,the digital positioning guide plate allowed rapid positioning and exposure of the SNTs while avoiding adjacent important anatomical structures.At 3-month follow-up,regeneration of bone and soft tissues was visible.CONCLUSION The application of digital positioning guide plates is useful for the individualized and minimalized extraction of impacted supernumerary teeth.

Comparative Evaluation of Implant Placement with Conventional and Digital Surgical Guide Techniques: Two Case Reports

Background: Implant placement using a conventional surgical guide and digital surgical guide techniques is well documented in the literature. The most frequently reported disadvantages of conventional surgical guide placement are lack of accuracy in implant placement when compared to three-dimensional assessment in digital technique. Other factors listed are longer time duration and the need for impression techniques. In this case report, the authors present a comparison between the two techniques and the time taken between both cases one done conventionally and another case by digital technique. Case Presentation: For the digital surgical guide, a 44-year-old, male reported with the chief complaint of missing teeth needing replacement was considered. For the conventional technique, a female patient aged fifty-seven who had gone through various dentists with an existing bridge was considered. This patient wanted a good outcome at a reasonable cost. In both cases, molars were missing and needed replacement. The steps for digital flow for a surgical guide and step-by-step conventional methods are both highlighted in this article. Conclusion: Hence the digital technique saved time and was accurate when compared to the conventional in our experience.