Prospects of 3D Printing Technology in Dental Medicine

With the continuous advancement of technology,the application of 3D printing technology in the field of dental medicine is becoming increasingly widespread.This article aims to explore the current applications and future potential of 3D printing technology in dental medicine and to analyze its benefits and challenges.It first introduces the current state of 3D printing technology in dental implants,crowns,bridges,orthodontics,and maxillofacial surgery.It then discusses the potential applications of 3D printing technology in oral tissue engineering,drug delivery systems,personalized dental prosthetics,and surgical planning.Finally,it analyzes the benefits of 3D printing technology in dental medicine,such as improving treatment accuracy and patient comfort,and shortening treatment times,while also highlighting the challenges faced,such as costs,material choices,and technical limitations.This article aims to provide a reference for professionals in the field of dental medicine and to promote the further application and development of 3D printing technology in this area.

Actual Practical Attitude and Knowledge of Dental Implants among Senior Dental Students and General Dentists Graduated from Some Saudi and Non-Saudi Dental Schools

Objective: To assess the actual practical attitude and knowledge of dental implants among senior dental students and general dentists graduated from some Saudi and Non-Saudi dental schools. Methods: A total of 300 senior dental students and general dentists participated in the study. Hard copies of the self-designed, multiple-choice questionnaires were distributed to all participants. The questionnaire consisted of 31 questions in five parts. Data were collected and analyzed using Chi-square test and t-test, where p Results: There is a statistically significant relationship between the participants’ answers, and their dental schools. Participants’ general knowledge, training, and teaching of dental implants, as well as information about restorations retained for the dental implants, were higher among participants from Saudi dental schools than participants from non-Saudi dental schools, while the information about dental implants was higher among participants from non-Saudi dental schools than participants from Saudi dental schools. Conclusion: We conclude that the actual practical attitude and knowledge of dental implants among participants in the current study was insufficient. Therefore, dental implant education in the undergraduate curricula of dental schools surveyed should be updated to include teaching, laboratory training, and preclinical and clinical training.

Surface demineralized freeze-dried bone allograft followed by reimplantation in a failed mandibular dental implant

The removal of a failed implant with high torque causes significant damage to the surrounding tissue,compromising bone regeneration and subsequent osseointegration in the defect area.Here,we report a case of carrier screw fracture followed by immediate implant removal,bone grafting and delayed reimplantation.A dental implant with a fractured central carrier screw was removed using the bur-forceps technique.The resulting three-wall bone defect was filled with granular surface demineralized freeze-dried bone allograft(SD-FDBA).Cone-beam computerized tomography was performed at 1week,6months and 15months postoperatively and standardized for quantitative evaluation.The alveolar bone width and height at 15months post-surgery were about 91%of the original values,with a slightly lower bone density,calculated using the gray value ratio.The graft site was reopened and was found to be completely healed with dense and vascularized bone along with some residual bone graft.Reimplantation followed by restoration was performed 8months later.The quality of regenerated bone following SD-FDBA grafting was adequate for osseointegration and longterm implant success.The excellent osteogenic properties of SD-FDBA are attributed to its human origin,cortical bone-like structure,partly demineralized surfaces and bone morphogenetic protein-2-containing nature.Further investigation with more cases and longer follow-up was required to confirm the final clinical effect.

Bone block from lateral window-correcting vertical and horizontal bone deficiency in maxilla posterior site:A case report

BACKGROUND Lateral window approach for sinus floor lift is commonly used for vertical bone augmentation in cases when the residual bone height is less than 5 mm.However,managing cases becomes more challenging when a maxillary sinus pseudocyst is present or when there is insufficient bone width.In this case,we utilized the bone window prepared during the lateral window sinus lift as a shell for horizontal bone augmentation.This allowed for simultaneous horizontal and vertical bone augmentation immediately after the removal of the maxillary sinus pseudocyst.CASE SUMMARY A 28-year-old female presented to our clinic with the chief complaint of missing upper left posterior teeth.Intraoral examination showed a horizontal deficiency of the alveolar ridge contour.The height of the alveolar bone was approximately 3.6 mm on cone beam computed tomography(CBCT).And a typical well-defined'dome-shaped'lesion in maxillary sinus was observed on CBCT imaging.The lateral bony window was prepared using a piezo-ultrasonic device,then the bony window was fixed to the buccal side of the 26 alveolar ridge using a titanium screw with a length of 10 mm and a diameter of 1.5 mm.The space between the bony window and the alveolar ridge was filled with Bio-Oss,covered with a Bio-Gide collagen membrane,and subsequently sutured.Nine months later,the patient’s bone width increased from 4.8 to 10.5 mm,and the bone height increased from 3.6 to 15.6 mm.Subsequently,a Straumann^(■)4.1 mm×10 mm implant was placed.The final all-ceramic crown restoration was completed four months later,and both clinical and radiographic examinations showed that the implant was successful,and the patient was satisfied with the results.CONCLUSION The bone block harvested from the lateral window sinus lift can be used for simultaneous horizontal bone augmentation acting as a shell for good two-dimensional bone augmentation.

Clinical efficacy,bone density,and follow-up in implant and orthodontic treatment for inclined adjacent teeth

BACKGROUND Tooth defects can cause elongation of occlusal teeth,leading to insufficient repair space.The combination of dental implant restoration and orthodontic treatment of oblique adjacent teeth has a significant therapeutic effect.AIM To explore clinical efficacy,bone density,and follow-up of implant and orthodontic treatment for patients with inclined adjacent teeth.METHODS In total,98 patients with oblique adjacent teeth were randomly assigned to implant restoration combined with orthodontic treatment(group A,n=49)or to receive implant restoration alone(group B,n=49).Changes in alveolar ridge bone density and apical bone density were observed before and after treatment in the two groups.Changes in chewing function and language function were compared between the two groups of patients.Follow-up lasted for 12 mo after repair to observe any adverse reactions in the oral cavity.RESULTS The clinical effective rates of group A and group B were 97.96%and 85.71%,respectively,with group A having a higher clinical effective rate than group B.After treatment,the bone density of the alveolar ridge and apical bone in both groups decreased compared to before treatment,while the chewing and language functions improved.The changes in various indicators in group A were more significant.After treatment,the satisfaction rate of group A(97.96%)was higher than that of group B(79.59%).The incidence of adverse reactions in group A(2.04%)was lower than that in group B(24.49%).CONCLUSION The amalgamation of implant restoration and orthodontic treatment for adjacent tilted teeth demonstrates notable clinical efficacy,diminishes alveolar bone resorption,and fosters patient functional rehabilitation while exhibiting negligible adverse reactions.

Osteotomy Protocol for Implant Insertion of One Day Biotech: One Drill, One Implant

Background: Four factors determine the quality of an implantology kit: 1) Heat generated by the drills;2) Morphology of the osteotomy according to the diameter of the implant;3) Efficiency of collecting autologous bone;and 4) Osteotomy execution time. Materials and Methods: This article examines the heat produced by drills during osteotomy, focusing on the effect of the following factors: drilling technique;volume of autologous bone harvested;drilling time;implant primary stability;and the percentage of osseointegrated implants after primary healing. Discussion: The four factors mentioned above are analyzed based on the data obtained for sequential, biological, and One Drill milling techniques. Conclusions: 1) One Drill is the fastest technique for performing the osteotomy;2) All techniques stay within the biological temperature range of living bone, with the lowest increase in temperature achieved using One Drill with irrigation;3) The bone harvested showed no statistically significant differences between biological milling and the One Drill technique, both far superior to the sequential technique;and 4) There is no statistically significant difference in the number of osseointegrated implants among the three techniques analyzed.

Anesthetic Effect of Compound Artevacaine Hydrochloride in Patients Undergoing Oral Implantation

Objective:To investigate and analyze the anesthetic effect of compound artevacaine hydrochloride in patients undergoing oral implantation.Methods:In this study,60 patients receiving oral implant surgery in our hospital were selected as the research subjects,and the operation time was from July 2019 to March 2021.Patients were randomly selected and divided into groups for the study.30 patients receiving lidocaine hydrochloride anesthesia were used as the control group,and 30 patients receiving compound artevacaine hydrochloride anesthesia were used as the research group.The anesthetic effect and safety of the two groups were compared and analyzed.Results:The anesthetic effect of the study group was significantly better than that of the control group(P<0.05).The blood pressure and heart rate in the study group were significantly lower than those in the control group(P<0.05).There was no significant difference in blood pressure and heart rate between the two groups before anesthesia(P>0.05).There was no significant difference in the incidence of ADR between the two groups(P>0.05).Conclusions:For patients undergoing oral implant surgery,choosing compound artevacaine hydrochloride as anesthetic drug has obvious anesthetic effect and can stabilize patients'life indexes.The anesthetic effect is obvious,and there is no obvious adverse reaction,and the clinical value is obvious.

Dental implant treatment for renal failure patients on dialysis:a clinical guideline

Chronic kidney disease （CKD） is a worldwide public health problem that is growing in prevalence and is associated with severe complications. During the progression of the disease, a majority of CKD patients suffer oral complications. Dental implants are currently the most reliable and successful treatment for missing teeth. However, due to complications of CKD such as infections, bone lesions, bleeding risks, and altered drug metabolism, dental implant treatment for renal failure patients on dialysis is more challenging. In this review, we have summarized the characteristics of CKD and previous publications regarding dental treatments for renal failure patients. In addition, we discuss our recent research results and clinical experience in order to provide dental implant practitioners with a clinical guideline for dental implant treatment for renal failure patients undergoing hemodialysis.

Impact of osteoporosis in dental implants:A systematic review

AIM: To assess the failure and bone-to-implant contact rate of dental implants placed on osteoporotic subjects. METHODS: Extensive examination strategies were created to classify studies for this systematic review. MEDLINE(via Pub Med) and EMBASE database were examined for studies in English up to and including May 2014. The examination presented a combination of the MeS H words described as follow: "osteoporosis" or "osteopenia" or "estrogen deficiency" AND "implant" or "dental implant" or "osseointegration". Assessment of clinical and/or histological peri-implant conditions in osteoporosis subjects treated with titanium dental implants. The examination included a combination of the MeS H terms described as follow: "osteoporosis" or "osteopenia" or "estrogen deficiency" AND "implant" or "dental implant" or "osseointegration".RESULTS: Of 943 potentially eligible articles, 12 were included in the study. A total of 133 subjects with osteoporosis, 73 subjects diagnosed with osteopenia and 708 healthy subjects were assessed in this systematic review. In these subjects were installed 367, 205, 2981 dental implants in osteoporotic, osteopenic and healthy subjects, respectively. The failure rate of dental implant was 10.9% in osteoporotic subjects, 8.29% in osteopenic and 11.43% in healthy ones. Bone-to-implant contact obtained from retrieved implants ranged between 49.96% to 47.84%, for osteoporosis and non-osteoporotic subjects. CONCLUSION: Osteoporotic subjects presented higher rates of implant loss, however, there is a lower evidence to strengthen or refute the hypothesis that osteoporosis may have detrimental effects on bone healing. Consequently, final conclusions regarding the effect of osteoporosis in dental implant therapy cannot be made at this time. There are no randomized clinical trial accessible for evaluation and the retrospectivenature of the evaluated studies shall be taken in account when interpreting this study.

Micromotions and combined damages at the dental implant/bone interface

Micromotion and fretting damages at the dental implant/bone interface are neglected for the limitation of check methods, but it is particularly important for the initial success of osseointegration and the life time of dental implant. This review article describes the scientific documentation of micromotion and fretting damages on the dental implant/bone interface. The fretting amplitude is less than 30 l^m in vitroand the damage in the interface is acceptable. While in vivo, the micromotion＇s effect is the combination of damage in tissue level and the real biological reaction.

Optics‑guided Robotic System for Dental Implant Surgery

At present,dental implant surgery mainly relies on the clinical experience of the doctor and the assistance of preoperative medical imaging.However,there are some problems in dental implant surgery,such as narrow space,sight obstruction,inaccurate positioning,and high requirements of doctors’proficiency.Therefore,a dental implant robot system(DIRS)guided by optical navigation is developed in this study,with an x-shaped tool and an irregular pentagonal tracer are designed for spatial registration and needle tip positioning strategy respectively.The coordinate system of each unit in DIRS is unified through system calibration,spatial registration,and needle tip positioning strategy.Then the surgical path is planned on the computed tomography(CT)images in the navigation software before operation.The automatic positioning method and the auxiliary positioning method can be used in the operation to achieve accurate positioning and assist doctors to complete the operation.The errors of spatial registration,needle tip positioning strategy,and the overall accuracy of the system were evaluated respectively,and the results showed that they all met the needs of clinical surgery.This study preliminarily verified the feasibility of the precise positioning method for dental surgery robots and provided certain ideas for subsequent related research.

Osteoblast integration of dental implant materials after challenge by sub-gingival pathogens: a co-culture study in vitro

Sub-gingival anaerobic pathogens can colonize an implant surface to compromise osseointegration of dental implants once the soft tissue seal around the neck of an implant is broken. In vitro evaluations of implant materials are usually done in monoculture studies involving either tissue integration or bacterial colonization. Co-culture models, in which tissue cells and bacteria battle simultaneously for estate on an implant surface, have been demonstrated to provide a better in vitro mimic of the clinical situation. Here we aim to compare the surface coverage by U2OS osteoblasts cells prior to and after challenge by two anaerobic sub-gingival pathogens in a co-culture model on differently modified titanium （Ti）, titanium-zirconium （TiZr） alloys and zirconia surfaces. Monoculture studies with either U2OS osteoblasts or bacteria were also carried out and indicated significant differences in biofilm formation between the implant materials, but interactions with U2OS osteoblasts were favourable on all materials. Adhering U2OS osteoblasts cells, however, were significantly more displaced from differently modified Ti surfaces by challenging sub-gingival pathogens than from TiZr alloys and zirconia variants. Combined with previous work employing a co-culture model consisting of human gingival fibroblasts and supra-gingival oral bacteria, results point to a different material selection to stimulate the formation of a soft tissue seal as compared to preservation of osseointegration under the unsterile conditions of the oral cavity.

Improvement of Systemic Symptoms after Dental Implant Removal

Dental implants have spread worldwide in dentistry. The risks and complications reported are limited to local issues. However, in this case, a patient complained of systemic symptoms after dental implantation. This case report aims to demonstrate that systemic symptoms such as lumbago, shoulder stiffness, neck pain, hip joint pain, and facial pain improved after the removal of well-osseointegrated titanium implants. The results suggest that harmful electromagnetic waves received by implants affect body conditions;however, to date, the underlying mechanisms have not been identified. Therefore, further research is required.

Investigation of a new design for zirconia dental implants

Objective:To assess the biomechanical properties of a new design configuration for zirconia dental implants. Methods: The new design has a cylindrical shape that is partially hollow and porous in the bottom, which permits the implants to be locked into the alveolar bone over time. It also utilizes bioactive glass coatings to increase adhesion to surrounding bone structure. Samples of the new design were fabricated in the laboratory and their material strength, hardness, and fracture toughness were evaluated. In addition, biocompatibility of the new design was evaluated through testing in dogs. Results: Results of mechanical tests indicate that structural properties of the new design exceed the usual requirements for implants. Moreover, animal tests suggest that there is appreciable improvement in lock-in strength and osteointegration. Conclusion: The new design configuration is biomechanically feasible and further research is warranted to improve the design for human use.

Posterior partially edentulous jaws, planning a rehabilitation with dental implants

AIM: To discuss important characteristics of the useof dental implants in posterior quadrants and the rehabilitation planning. METHODS: An electronic search of English articles was conducted on MEDLINE(PubM ed) from 1990 up to the period of March 2014. The key terms were dental implants and posterior jaws, dental implants/treatment planning and posterior maxilla, and dental implants/treatment planning and posterior mandible. No exclusion criteria were used for the initial search. Clinical trials, randomized and non randomized studies, classical and comparative studies, multicenter studies, in vitro and in vivo studies, case reports, longitudinal studies and reviews of the literature were included in this review. RESULTS: One hundred and fifty-two articles met the inclusion criteria of treatment planning of dental implants in posterior jaw and were read in their entirety. The selected articles were categorized with respect to their context on space for restoration, anatomic considerations(bone quantity and density), radiographic techniques, implant selection(number, position, diameter and surface), tilted and pterygoid implants, short implants, occlusal considerations, and success rates of implants placed in the posterior region. The results derived from the review process were described under several different topic headings to give readers a clear overview of the literature. In general, it was observed that the use of dental implants in posterior region requires a careful treatment plan. It is important that the practitioner has knowledge about the theme to evaluate the treatment parameters. CONCLUSION: The use of implants to restore the posterior arch presents many challenges and requires a detailed treatment planning.

Surface treatment of titanium dental implant with H2O2 solution

The surface treatment is important for titanium and its alloys as promising candidates for dental implantation due to their bioinert surface.Titanium surface samples were modified using H2O2 solution at different times up to 72 h to boost their bioactivity.According to the results of the field emission scanning electron microscopy test,some nanostructures are formed on the surface of treated titanium samples and increased in size by increasing the time of treatment up to 24 h.After 24 h of application,the sharpness of nanostructures decreased and the micro-cracks and discontinuity in the coating surface increased.The results of the X-ray diffraction study and Raman spectroscopy revealed that anatase(TiO2)was formed on the surface of treated titanium samples.The peak intensity of Raman spectroscopy increased with an improvement in treatment time of up to 24 h and then decreased due to the discontinuity of the coating.Full wettability and ability to form apatite were reached at 6 h of treatment.It is clear that the treatment time has a significant effect on the surface treatment of titanium using the H2O2 solution.

Oblique Cutting Based Mechanical Model for Insertion Torque of Dental Implant

The insertion torque of a dental implant is an important indicator for the primary stability of dental implants.Thus,the preoperative prediction for the insertion torque is crucial to improve the success rate of implantation surgery.In this present research,an alternative method for prediction of implant torque was proposed.First,the mechanical model for the insertion torque was established based on an oblique cutting process.In the proposed mechanical model,three factors,including bone quality,implant geometry and surgical methods were considered in terms of bone-quality coefficients,chip load and insertion speeds,respectively.Then,the defined bone-quality coefficients for cancellous bone with the computed tomography(CT)value of 235–245,345–355 and 415–425 Hu were obtained by a series of insertion experiments of IS and ITI implants.Finally,the insertion experiments of DIO implants were carried out to verify the accuracy of developed model.The predicted insertion torques calculated by the mechanical model were compared with those acquired by insertion experiments,with good agreement,the relative error being less than 15%.This method allows the insertion torque for different implant types to be quickly established and enhances prediction accuracy by considering the effects of implants’geometries and surgical methods.

Mineralized and Osteoid Tissue from Dental Pulp Stem Cells on Micro-arc Oxidation Titanium in vitro

The presence of insufficient bone volume affects the implant healing and success.The aim of this study was to evaluate osteogenic capacity of dental pulp stem cells(DPSCs) on micro-arc oxidation(MAO) titanium surface.DPSCs were challenged at MAO and smooth titanium surface separately for different durations,and the bone marrow mesenchymal stem cells(BMSCs) served as the positive controls.The osteogenic capacity of DPSCs on MAO titanium surface was assessed by using scanning electron microscopy,energy dispersive spectroscopy,biochemical tests and real-time quantitative PCR.Data showed that DPSCs differentiated into osteoblasts and expressed bone morphogenetic genes on MAO titanium surface.The results of this study revealed that DPSCs had good potential to generate mineralized tissue on MAO titanium plates.The differential potential of DPSCs may be regulated by MAO titanium surface.The osteogenesis potential of DPSCs on the MAO titanium was similar with BMSCs.

New Mini Dental Implant Attachments versus O-ring Attachment after Cyclic Aging: Analysis of Retention Strength and Gap Space

Overdenture as a treatment modality for both partially and fully edentulous patients is costeffective and less expensive. The purpose of the present study was to examine the newly fabricated attachments by comparing them with conventional O-ring attachment in vitro in terms of retention force and cyclic aging resistance. A total of 150 samples were prepared and divided into five groups according to the materials used(O-ring attachment, Deflex M10 XR, Deflex Classic SR, Deflex Acrilato FD, and flexible acrylic resin). The retention force of different attachments was measured by a mini dental implant after three subsequent aging(0, 63, and 126) cycles in the circumstances similar to the oral environment. The gap space between the head of the implant and the inner surface of the attachments was detected. Two-way analysis of variance(ANOVA) analysis with multiple comparisons test was applied for statistical analysis. The results showed that Deflex M10 XR had the highest retention force and the lowest gap space after cyclic aging; in addition, by comparing the relative force reduction, the lowest values were obtained in the O-ring attachment and the highest values in the flexible acrylic resin attachment. The retention force measured after cyclic aging for the Deflex M10 XR attachment was greatly improved when compared with the O-ring attachment and other types of attachment materials; in addition, the Deflex M10 XR attachment exhibited the minimum gap space between the inner surface and the mini dental implant head. In conclusion, Deflex M10 XR has the ability to withstand weathering conditions and retains its durable and retentive properties after aging when compared with other attachments.

Mechanical Experiment for 3D Printing of Titanium Bone Bionic Dental Implants

[Objectives] To explore the flexural strength of 3D printed titanium bone bionic dental implants and provide a scientific basis for the clinical application of 3D printed porous bionic bone dental implants. [Methods] The cone-beam CT( CBCT) image information of 20 premolars extracted by orthodontic requirement was collected,and a new porous bone bionic dental implant was produced using modeling software and 3D printer. The premolars were divided into two groups( A and B). The universal testing machine was used to test the flexural strength of the two groups and the difference in flexural strength between the two groups was compared through statistics. [Results]Twenty 3D printed porous titanium bone bionic implants were accurately produced; the morphology of group A and group B were extremely similar to each other; the average flexural strength of group A was 2 767. 92 N,while the average flexural strength of group B was 778. 77 N,showing that the average flexural strength of group A was significantly higher than that of group B,and the difference was statistically significant( P < 0. 05).[Conclusions]The personalized porous structure root implants produced by 3D printing technology are very similar to the target tooth morphology,and show high accuracy and small error of production. Besides,the flexural strength of 3D printed personalized porous structure root implants can fully meet the requirements of the maximum occlusal force for dental implant restoration. It is expected to provide a scientific basis for clinical application of 3 D printed porous bionic bone tooth implants.