Soft tissue response and determination of underlying risk drivers for recession and mucositis after AMSJI implantation in the maxilla.

PURPOSE: There are few treatment options for oral rehabilitation in patients with advanced maxillary resorption (Cawood-Howell Class V or more). Patient-specific, 3D-printed titanium subperiosteal implants have been described as a potentially valuable alternative solution. Surgeon and patient mediated functional outcomes have been studied and the results are promising. The surrounding soft tissue health has been much less researched. This study aims to evaluate the soft tissue response to the placement of additively manufactured subperiosteal jaw implants (AMSJI®) in the severely atrophic maxilla and to identify possible risk factors for soft tissue breakdown. MATERIALS AND METHODS: An international multicenter study was conducted and fifteen men (mean age 64.62 years, SD ± 6.75) and twenty-five women (mean age 65.24 years, SD ± 6.77) with advanced maxillary jaw resorption (Cawood-Howell Class V or more) were included in this study. General patient data were collected and all subjects were clinically examined. Inclusion criteria were patients who underwent bilateral AMSJI placement® in the maxilla at least a year before and whose surgeon and themselves agreed to participate in the study before their inclusion. RESULTS: A total of forty patients were enrolled with a mean follow-up period of 917 days (SD ± 306.89 days). Primary stability of the implant was achieved postoperatively in all cases, and all implants were loaded with a final prosthesis. At the time of study, only one patient showed mobility of the bilateral AMSJI (more than 1 mm). Exposure of the framework, due to mucosal recession, was seen in 26 patients (65%) and was mainly in the left (21.43%) and right (18.57%) mid-lateral region. Thin biotype and the presence of mucositis were found to be risk factors (p-value < 0.05). Although not significant, smokers had a nearly seven times (Odds ratio 6.88, p=0.08) more risk of developing a recession compared to nonsmokers. CONCLUSION: Twenty-six (65%) patients presented with a recession in one or (more) of the seven regions after oral rehabilitation with bilateral AMSJI installation. Several risk drivers were evaluated. The collapse of soft tissues around the AMSJI that led to caudal exposure of the arms was correlated with a thin biotype and the presence of mucositis.

The ideal shape of the female jaw angle: An online survey.

The aim of this study was to determine the characteristics of an attractive white female jaw angle in the three dimensions. An online survey of photographs of celebrities and laypeople was used to rate their attractiveness using 6 questions and a 3-item Likert scale. If ≥ 80% of participants rated a model as having attractive aesthetic features, it was considered attractive. The following features were considered important: a gonial angle in profile of 125.5° and in anterior view of 142°, an intergonial-interzygomatic width ratio of 0.83 and the vertical position of the jaw angles at the level of the stomion or upper lip. Surgeons can use these consensus criteria to help design a jaw angle implant, define orthognathic surgical strategies, or shape the angle using injectables.

Patient Satisfaction and Impact on Oral Health after Maxillary Rehabilitation Using a Personalized Additively Manufactured Subperiosteal Jaw Implant (AMSJI).

Subperiosteal implants (SIs) were first developed by Dahl in 1941 for oral rehabilitation in case of severe jaw atrophy. Over time, this technique was abandoned due to the high success rate of endosseous implants. The emergence of patient-specific implants and modern dentistry allowed a revisitation of this 80-year-old concept resulting in a novel "high-tech" SI implant. This study evaluates the clinical outcomes in forty patients after maxillary rehabilitation with an additively manufactured subperiosteal jaw implant (AMSJI®). The oral health impact profile-14 (OHIP-14) and numerical rating (NRS) scale were used to assess patient satisfaction and evaluate oral health. In total, fifteen men (mean age: 64.62 years, SD ± 6.75 years) and twenty-five women (mean age: 65.24 years, SD ± 6.77 years) were included, with a mean follow-up time of 917 days (SD ± 306.89 days) after AMSJI installation. Patients reported a mean OHIP-14 of 4.20 (SD ± 7.10) and a mean overall satisfaction based on the NRS of 52.25 (SD ± 4.00). Prosthetic rehabilitation was achieved in all patients. AMSJI is a valuable treatment option for patients with extreme jaw atrophy. Patients enjoy treatment benefits resulting in high patient satisfaction rates and impact on oral health.

Prevention and non-surgical treatment of soft tissue polly beak deformity after rhinoplasty: a scoping review.

The aim of this study is to map the available evidence of surgical preventive measures and postoperative methods for addressing supratip fibrosis (polly beak deformity) following rhinoplasty, to describe the postoperative results and to identify the most effective techniques. A scoping review was performed, selecting articles from the following medical electronic databases: PubMed, Cochrane Central, EMBASE, and Web of Science up to October 2022. The following keywords were used: supratip fullness, supratip deformity, polly beak deformity and supratip fibrosis. A total of 19 studies met the eligibility criteria. Of these 18 were included, and were divided into two categories: studies that solely used non-surgical management and studies that used operative techniques to prevent soft tissue polly beak deformity. Cartilaginous causes of polly beak deformity were excluded. Although a number of different methods are described in literature, the effectiveness and potential of each are still open to debate. Randomized controlled trials that use a standardized objective measurement method for soft tissue polly beak deformity are needed to objectively compare different methods.

On the use of intraoperative 3D-RX C-arm imaging in orthognathic surgery: a prospective non-consecutive case series study.

CONTEXT: Segment and osteosynthesis malposition resulting in patients' complaints (mainly about asymmetries) are encountered in orthofacial/orthognathic surgery. OBJECTIVE, DESIGN, AND SETTING: We planned to investigate the usefulness of intraoperative three-dimensional (3D) imaging concerning positioning and fixation of bone segments and osteosynthesis in orthognathic/orthofacial surgery. We performed a prospective study of non-consecutive cases. All patients receiving a bimaxillary osteotomy, genioplasty, and their combinations were included in the study from May 2016 to May 2020. Unilateral and bilateral sagittal split osteotomies were excluded. There were no gender and age limitations. All were intraoperatively examined using the BV Pulsera 3D-RX System (Philips Medical, Eindhoven, The Netherlands). The outcome variables were the percentage of revisions of segment positioning and osteosynthesis. Predictor variables were age, gender, type of surgery, timing (pre- and post-imaging), and surgeon experience (senior vs assistant). RESULTS: Forty female and twenty-two male patients were included (mean age 25.25 years ± 7.52 and 29.1 years ± 12.6 respectively). We evaluated 27 genioplasties and 34 Le Fort "type-I" osteotomies. Indications for segment repositioning and redo-osteosynthesis increased after intraoperative imaging as compared to operator's clinical judgment before intraoperative imaging (95% confidence interval; p < .001 and p = .002 respectively). CONCLUSION: Suboptimal positioning and fixation of bone segments or osteosynthesis were more apparent with 3D imaging. In addition, some satisfactory cases were also revised for an optimal outcome. As a result, surgeons were prompted to more revisions than judged necessary without intraoperative imaging.

How surface coatings on titanium implants affect keratinized tissue: A systematic review.

Apart from osseointegration, the stability and long-term survival of percutaneous titanium implants is also strongly dependent on a qualitative soft-tissue integration in the transcutaneous region. A firm connective tissue seal is needed to minimize soft-tissue dehiscence and epithelial downgrowth. It is well-known that the implant surface plays a key role in controlling the biological response of the surrounding keratinized tissue and several coating systems have been suggested to enhance the soft-tissue cell interactions. Although some promising results have been obtained in vitro, their clinical significance can be debated. Therefore, the purpose of this systematic review is to gain more insight into the effect of such coatings on the interface formed with keratinized soft-tissue in vivo. A comprehensive search was undertaken in March 2021. Relevant electronic databases were consulted to identify appropriate studies using a set of search strings. In total, 12 out of 4971 publications were included in this review. The reported coating systems were assigned to several subgroups according to their characteristics: metallic, ceramic and composite. Notwithstanding the differences in study characteristics (animal model, implantation period, reported outcomes), it was noticed that several coatings improve the soft-tissue integration as compared to pristine titanium. Porous titanium coatings having only limited pore sizes (<250 µm) do not support dermal fibroblast tissue attachment. Yet, larger pores (>700 µm) allow extensive vascularized soft-tissue infiltration, thereby supporting cell attachment. Nanostructured ceramic coatings are found to reduce the inflammatory response in favor of the formation of cell adhesive structures, that is, hemidesmosomes. Biomolecule coatings seem of particular interest to stimulate the soft-tissue behavior provided that a durable fixation to the implant surface can be ensured. In this respect, fibroblast growth factor-2 entrapped in a biomimetic apatite coating instigates a close to natural soft-tissue attachment with epidermal collagen fibers attaching almost perpendicular to the implant surface. However, several studies had limitations with respect to coating characterization and detailed soft-tissue analysis, small sample size and short implantation periods. To date, robust and long-term in vivo studies are still lacking. Further investigation is required before a clear consensus on the optimal coating system allowing enhancing the soft-tissue seal around percutaneous titanium implants can be reached.

Surface wear in a custom manufactured temporomandibular joint prosthesis.

The wear of a novel temporomandibular joint (TMJ) prosthesis was evaluated in an animal model. The prosthesis consisted of an additively manufactured titanium alloy (Ti6 Al4 V) mandibular condyle and glenoid fossa created through selective laser melting, with a machined vitamin E-enriched ultra-high molecular weight polyethylene (UHMWPE) surface attached to the fossa. Thirteen TMJ prosthesis were implanted in sheep, six of which had condylar heads coated with HadSat® diamond-like carbon (H-DLC). Euthanasia took place after 288 days, equaling 22 years of human mastication. Linear and volumetric wear analysis of the fossa was performed by optical scanning. The condylar head surfaces were assessed by scanning electron and confocal laser microscopy. The average linear UHMWPE wear, when combined with the coated condyle, was 0.67 ± 0.28 mm (range: 0.34-1.15 mm), not significantly differing (p = .3765, t-test) from the non-coated combination average (0.88 ± 0.41 mm; range: 0.28-1.48 mm). The respective mean volumetric wear volumes were 25.29 ± 11.43 mm3 and 45.85 ± 22.01 mm3 , not significantly differing (p = .1448, t-test). Analysis of the coated condylar surface produced a mean Ra of 0.12 ± 0.04 µm and Sa of 0.69 ± 0.07 µm. The non-coated condylar surface measured a mean Ra of 0.28 ± 0.17 µm and Sa of 2.40 ± 2.08 µm. Both Sa (p = .0083, Mann-Whitney U test) and Ra (p = .0182, Mann-Whitney U test), differed significantly. The prosthesis exhibits acceptable wear resistance and addition of the H-DLC-coating significantly improved long-term condylar surface smoothness.

Obstacles for accessing customised craniofacial implants in low- and middle-income countries.

INTRODUCTION: Many low resourced low- and middle-income countries (LMICs) do not have access to (high tech) developments in the medical field. The aim of this study is to research how a contemporary high-tech solution, such as customized medical implants, can be transferred to low resource LMICs. MATERIALS AND METHODS: We explored the internet to retrieve data regarding internet coverage, services providing free email accounts, and the availability of connecting devices. Additionally, a computerized search was performed for currently available PSI concepts and other important emerging technologies with potential value in craniomaxillofacial surgery. Lastly, we searched the internet for the availability of CT scan devices and smartphones in the LMICs. RESULTS: Internet penetration and access to computers/smartphones is low in the LMIC's. Moreover, availability of radiology departments and radiologist is very limited (60 radiologist per 190 million Nigerian inhabitants) and a lack of knowledge concerning import regulations and customs clearance, limit the accessibility/availability for patient-specific implants, since this is crucial in developing and delivering these devices. Lastly, appropriate training and instrumentation is vital (yet, currently difficult) to acquire and foresee, in order to achieve the best post-operative results. CONCLUSION: This research confirms great difficulties achieving our aims but with persistence and adoption of well-constructed programs it should be possible.

Need for velopharyngeal surgery after primary palatoplasty in cleft patients. A retrospective cohort study and review of literature.

BACKGROUND: Enabling intelligible speech plays an important role in achieving social inclusion and a good quality of life of cleft patients. A crude measure of primary palatal repair quality is the incidence of operations to correct velopharyngeal insufficiency (VPI) after speech-language therapy has proven inadequate. This study assessed the necessity for surgery to correct velopharyngeal insufficiency following our standardized two-staged protocol, compared the results with the literature, and identified factors that may influence velopharyngeal competence. METHODS: A review of the literature was performed. The outcome measure in our series was the necessity for a secondary procedure to correct velopharyngeal insufficiency. The results of literature review were compared with the results of our case series, which we treated using a standardized protocol. RESULTS: In our retrospective study, 5 patients (2.5%) required secondary pharyngoplasty. In literature, the frequency of surgery to correct velopharyngeal insufficiency after one- and two-stage protocols were 13.6% and 24.5%, respectively. No statistical difference was found between bilateral and unilateral clefts. The frequencies of velopharyngeal surgery were 7.2% after Furlow palatoplasty, 17.5% after a 2-flap palatoplasty, 18.6% after a Wardill-Killner palatoplasty, and 35.6% after a Von Langenbeck palatoplasty. CONCLUSION: The literature reported that one-stage palatoplasty is correlated with a lower incidence of secondary pharyngeal surgery. Our standardized two-stage protocol proved successful in avoiding secondary velopharyngeal surgery but due to the reduced number of patients included in our study, more research is needed.

Radiographic Evaluation of Bone Remodeling after Additively Manufactured Subperiosteal Jaw Implantation (AMSJI) in the Maxilla: A One-Year Follow-Up Study.

Additively manufactured subperiosteal jaw implants (AMSJI) are patient-specific, 3D-printed, titanium implants that provide an alternative solution for patients with severe maxillary bone atrophy. The aim of this study was to evaluate the bony remodeling of the maxillary crest and supporting bone using AMSJI. Fifteen patients with a Cawood-Howell Class V or greater degree of maxillary atrophy were evaluated using (cone beam) computed tomography scans at set intervals: one month (T1) and twelve months (T2) after definitive masticatory loading of bilateral AMSJI implants in the maxilla. The postoperative images were segmented and superimposed on the preoperative images. Fixed evaluation points were determined in advance, and surface comparison was carried out to calculate and visualize the effects of AMSJITM on the surrounding bone. A total mean negative bone remodeling of 0.26 mm (SD 0.65 mm) was seen over six reference points on the crest. Minor bone loss (mean 0.088 mm resorption, SD 0.29 mm) was seen at the supporting bone at the wings and basal frame. We conclude that reconstruction of the severely atrophic maxilla with the AMSJI results in minimal effect on supporting bone. Reduced stress shielding with a biomechanically tuned subperiosteal implant does not induce radiographically significant crestal bone atrophy.

Additively manufactured titanium scaffolds and osteointegration - meta-analyses and moderator-analyses of in vivo biomechanical testing.

INTRODUCTION: Maximizing osteointegration potential of three-dimensionally-printed porous titanium (3DPPT) is an ongoing focus in biomaterial research. Many strategies are proposed and tested but there is no weighted comparison of results. METHODS: We systematically searched Pubmed and Embase to obtain two pools of 3DPPT studies that performed mechanical implant-removal testing in animal models and whose characteristics were sufficiently similar to compare the outcomes in meta-analyses (MAs). We expanded these MAs to multivariable meta-regressions (moderator analysis) to verify whether statistical models including reported scaffold features (e.g., "pore-size", "porosity", "type of unit cell") or post-printing treatments (e.g., surface treatments, adding agents) could explain the observed differences in treatment effects (expressed as shear strength of bone-titanium interface). RESULTS: "Animal type" (species of animal in which the 3DPPT was implanted) and "type of post-treatment" (treatment performed after 3D printing) were moderators providing statistically significant models for differences in mechanical removal strength. An interaction model with covariables "pore-size" and "porosity" in a rabbit subgroup analysis (the most reported animal model) was also significant. Impact of other moderators (including "time" and "location of implant") was not statistically significant. DISCUSSION/CONCLUSION: Our findings suggest a stronger effect from porosity in a rat than in a sheep model. Additionally, adding a calcium-containing layer does not improve removal strength but the other post-treatments do. Our results provide overview and new insights, but little narrowing of existing value ranges. Consequent reporting of 3DPPT characteristics, standardized comparison, and expression of porosity in terms of surface roughness could help tackle these existing dilemmas.

Evaluation of Patient-Specific Cranial Implant Design Using Finite Element Analysis.

BACKGROUND: Various studies have investigated the load-bearing capacity of patient-specific cranial implants. However, little attention has been given to the evaluation of the design of ceramic-titanium (CeTi) implants. METHODS: A biomechanical evaluation of 3 patient-specific cranial implants was performed using finite element analysis. RESULTS: The results of the analyses allowed the identification of the implant regions as well as the magnitudes of the maximum stresses on, and displacements along, these regions after traumatic impact. The analyses also showed that polyether ether ketone cranial implants offer inferior brain and neurocranial protection due to their high flexibility and local peak stresses at the bone-screw interface. In contrast, CeTi implants were able to evenly distribute the stresses along the interface and thus reduced the risk of neurocranial fracture. The scaffold structure at the border of these implants reduced stress shielding and enhanced bone ingrowth. Moreover, brain injuries were less likely to occur, as the CeTi implant exhibits limited deflection. CONCLUSIONS: From the finite element analyses, CeTi cranial implants appear less likely to induce calvarial fractures with a better potential to protect the brain under impact loads.

Lateral pterygoid muscle enthesis reconstruction in total temporomandibular joint replacement: An animal experiment with radiological correlation.

A novel total temporomandibular joint replacement (TMJR) was developed with CADskills BV (Ghent, Belgium), aiming to achieve reinsertion of the (LPM) onto a scaffold in the implant. In order to investigate the possibility of reinsertion of the LPM, an animal experiment was conducted. An in vivo sheep experiment was conducted, which involved implanting sheep with a TMJR. Clinical parameters were recorded regularly and computed tomography (CT) scan images of two randomly selected sheep per scan were made at 1, 3, and 6 months. After 9.5 months, the sheep were euthanized, and CT scans of all animals were performed in order to evaluate the LPM's enthesis. A total of 13 sheep were implanted with a TMJR. One sheep was used as a sham. Radiographs revealed four outcome types of enthesis reconstruction. In four sheep, there was no reconstruction between the implant and the LPM. In three sheep, there was a purely soft tissue connection of 0.5-0.9 mm (average 0.7 mm) between the ostectomized bony LPM insertion and the implant's lattice structure. A combination of partial bony and partial soft tissue enthesis attachment (0.3-0.5 mm, average 0.4 mm) was found in three sheep. A bony ingrowth of the enthesis into the scaffold occurred in two sheep. A secondary bony connection between the mandible and the insertion of the LPM was found in 10 of 13 sheep. Four fossa components were found to be displaced, yet TMJ function remained in these ewes. The heterotopic ossification that was seen may be a confounding factor in these results. This in vivo experiment showed promising results for improving the current approach to TMJR with the possibility of restoring the laterotrusive function. The fossa displacement was considered to be due to insufficient fixation and predominant laterotrusive force not allowing for proper osseointegration. Further optimization of the reattachment technique, scaffold position and surface area should be done, as well as trials in humans to evaluate the effect of proper revalidation.

Third-generation slotplates for orthognathic and facial corrective surgery.

The aim of this study was to retrospectively assess the osteosynthesis material-related morbidity rates of third-generation (3.0) slotplates, and to compare those with the previously researched second-generation (2.0) slotplates. In the 2.0 slotplate design, there were additional tabs in line with the vertical slotted screw hole; in between these tabs, the additional locking screw was placed. In the 3.0 slotplates, these tabs were replaced by a full screw hole for the locking screw, and the 3.0 slotplates are slightly broader than the 2.0 slotplates. Osteosynthesis material-related morbidity rates after Le Fort I-type, zygoma-valgisation, and chin osteotomies were assessed in a cohort receiving 3.0 slotplates in a tertiary care centre and compared to a previously analysed cohort receiving 2.0 slotplates in the same tertiary care centre. Medical records of 77 patients (101 surgeries) receiving 3.0 slotplates were reviewed. Plate infection and plate removal rates were low in the 3.0 slotplate group (2.6% (p = 0.123) and 3.9% (p = 0.103), respectively). No delayed union or non-union occurred in the 3.0 slotplate group. Comparing the morbidity rates with the 2.0 slotplate cohort did not yield any significant differences. Although there was a tendency towards better outcomes with 3.0 slotplates compared to the 2.0 slotplates, the outcome differences did not reach statistical significance.

The need for maxillary osteotomy after primary cleft surgery: A systematic review framing a retrospective study.

OBJECTIVE: This study assessed the rate of maxillary osteotomies after cleft palate surgery following a standardized two-stage palatoplasty protocol. In order to improve our treatment strategy, the results were compared with the data extracted from the literature by means of a systematic review. DESIGN: Retrospective cohort study. PATIENTS: Non-syndromic cleft lip, alveolus, and palate patients with complete records who underwent primary cleft palate surgery. INTERVENTION: The incidence of midface hypoplasia after primary cleft surgery that required surgical intervention was retrospectively evaluated. RESULTS: Of the final 51 patients included in our retrospective analysis, two required a maxillary repositioning osteotomy. The frequency was lower than reported in the literature. In the literature, there was no difference between patients treated according to a one-stage protocol (21%) and patients treated according to a two-stage protocol (20.8%), but a higher incidence of pharyngeal surgery was noted in the two-stage closure group. Only the cleft type, timing of hard palate closure, and orthodontic treatment proved to influence the need for maxillary osteotomy. CONCLUSION: Our protocol shows promising results and needs more validation.

Total Temporomandibular Joint Replacement: Stick to Stock or Optimization by Customization?

PURPOSE: This article aims to compare the difference in postoperative results in patients treated with either a patient-specific (PSI) or a stock temporomandibular total joint replacement system. MATERIALS AND METHODS: The investigators performed a systematic review concerning postoperative results after placement of either a stock total joint replacement system or a PSI. PubMed Central, Web of Science, Cochrane Library Plus, Wiley Online Library, and EMBASE were used to conduct this search. All articles up to August 15, 2018, were scrutinized. All included articles were nonrandomized cohort studies. Maximal mouth opening (MMO) and Visual Analog Scale (VAS) scores for pain and diet before and after surgery were evaluated. The Methodological Index for NonRandomized Studies scale was used for quality assessment. Weighted mean difference was calculated and pooled by meta-analysis using random-effect models. RESULTS: The search identified 1581 articles, of which 15 were included. The average risk of bias was low. Both systems achieved significant increases in MMO and decreased VAS pain scores at 1, 2, and 3 years after surgery. No significant difference was found between the system types. Both achieved significant improvements in dietary VAS scores, with a more significant improvement for stock implants. CONCLUSIONS: Due to the lack of detailed diagnostic evaluation tools allowing proper start-point categorization, there is a significant risk for selection bias in the pooled data. The PSI is more frequently chosen for cases with more significant joint degeneration, skewing postoperative results. A patient-fitted implant can provide significant operative and patient-centered advantages over a stock implant, which will likely be confirmed when observational cohort studies have included indications like the ones for stock prostheses. Furthermore, while current US Food and Drug Administration-approved stock implants contain cobalt -chromium -molybdenum, the newly manufactured PSI are made of titanium alloy, diminishing the risks of morbidity and implant failure.

A prospective study of soft- and hard-tissue changes after mandibular advancement surgery: Midline changes in the chin area.

INTRODUCTION: The purpose of this research was to prospectively determine the ratio of 2 soft-tissue landmarks, pogonion (sPg) and menton (sMe), to their hard-tissue counterparts (Pg and Me) in the sagittal and vertical directions for mandibular lengthening surgeries. METHODS: We drew a sample from the prospective Orthognathic and Orthofacial Surgery Research study, consisting of patients who underwent surgical mandibular lengthening (alone or in combination with maxillary osteotomy) without genioplasty. We digitized landmarks using Facewizz software and determined the relationships between the hard- and soft-tissue changes by correlation analysis. RESULTS: Pearson correlation test showed a significant correlation between the type of surgery and the sPg:Pg and sMe:Me ratios. The sPg:Pg ratio was 87% for mandibular lengthening only and 102% for mandibular lengthening in combination with maxillary surgery. The sMe:Me ratio was 85% and 96% for upward and downward movements, respectively. CONCLUSIONS: The average ratios presented in this study for the pogonion and menton can aid in preoperative planning by providing estimates for soft-tissue behavior. Further stratifications will be possible after the Orthognathic and Orthofacial Surgery Research database is enriched with more inclusions.

Guidelines for the Use of Resection Guides for Subperiosteal Maxillary Implants in Cases of Terminal Dentition - A Novel Approach.

INTRODUCTION: We described our rationale and experiences with the use of cutting jigs for vertical ostectomy in cases of terminal maxillary dentition when edentulation and an additively manufactured subperiosteal jaw implant (AMSJI®) are planned. MATERIAL AND METHODS: Our experience covers 15 patients treated by four clinicians. We tabulated our criteria for planning and manufacturing vertical and horizontal ostectomy guides. RESULTS: In order to guarantee accurate osteotomy, titanium guides are preferable to guides made of polymer. The most important consideration is to avoid acute angles in the buccal arms of the AMSJI®. It is up to the surgeon whether to screw-fix the ostectomy guides or to use handles to maintain their position. DISCUSSION: Guided ostectomy has the potential to extend the use of AMSJI® to cases where teeth have yet to be removed or where the contours of the residual bone are not favorable. The use of guided ostectomy in such cases lessens the time between edentulation and implantation and improves the design of the implants.

Ceramic 3D-Printed Titanium Cranioplasty.

STUDY DESIGN: Inlay cranioplasties following partial craniectomy in tumor or trauma cases and onlay cranioplasties for reconstructions of residual developmental skull anomalies are frequently performed using CAD-CAM techniques. OBJECTIVE: In this case series, we present a novel cranial implant design, being a combination of 3D-printed titanium grade 23 and calcium phosphate paste (CeTi). METHODS: The titanium patient-specific implant, manufactured using selective laser melting, has a latticed border with interconnected micropores. The cranioplasty is miniscrew fixed and its border zone subsequently partially filled with calcium phosphate paste to promote osteoinduction and osteoconduction. From April 2017 to April 2019, 8 patients have been treated with such a CeTi implant. The inlay cranioplasties were each time revision surgeries of complicated cases. RESULTS: All implants were successful after a limited follow-up time (range 18-42 months). There were no dehiscences and no infections, and no complaints of thermal conduction. CONCLUSIONS: The proposed CeTi cranial implant combines the strength of titanium implants with the biological integration potential of ceramic implants and seems particularly resistant to infection, probably due to the biofunctionalized titanium surface and the antimicrobial activity of elevated intracellular free calcium levels.

On the reinsertion of the lateral pterygoid tendon in total temporomandibular joint replacement surgery.

This report aims to present the concept of reestablishing lateral pterygoid muscle function during total temporomandibular joint (TMJ) replacement surgery. The key feature is a lattice structure (scaffold) located in the condylar neck of a titanium, three-dimensionally (3D)-printed mandibular component that houses morselized autologous bone from the resected condyle and osteogenic stem cells from iliac bone marrow aspirate, and to which the fibrous enthesis component (collagen attachments to a bone fragment) is fixed via suture cerclage prior to the development of the bony union. Five TMJs were replaced using enthesis reconstruction in three patients who were followed for 1 year and more. Laterotrusion to the contralateral side measured on average 6.4 mm preoperatively, 2.3 mm at 1 month, 3 mm at 3 months, 4 mm at 6 months, and at 1-1.5 years (62,5% of the preoperative laterotrusion/40% of a normal laterotrusion). Subjective normalization of mastication after 1 year was present in all patients. A successful reattachment of the enthesis to an alloplastic endoprosthesis suggests that patients will not only be able to open and close their mouths properly with reduced pain but will also be able to actually chew. The technique has potential applications in orthopedic alloplastic reconstruction.