Peri-implantitis and maxillary sinus membrane thickening: A retrospective cohort study.

OBJECTIVE: The objective of this study is to investigate the association of peri-implantitis (PI) and sinus membrane thickening and to assess the resolution of membrane thickening following intervention (implant removal or peri-implantitis treatment) aimed at arresting PI. MATERIALS AND METHODS: Forty-five patients with 61 implants in the posterior maxillary region were retrospectively included in the study. Twenty-four patients were diagnosed with peri-implantitis (PI) and 21 had peri-implant health (PH). Cone-beam computed tomography (CBCT) scans were evaluated to assess maxillary sinus characteristics, including membrane thickening, sinus occupancy and ostium patency. The CBCT scans taken 6 months after intervention aimed at arresting disease (implant removal or treatment of PI) in the PI group were also appraised and compared to baseline scans. RESULTS: At baseline, all parameters evaluating membrane thickness disorders yielded significant differences between groups (p < .001). Patients with posterior maxillary implants diagnosed with PI were 7× more likely to present membrane thickening compatible with pathology when compared to patients with healthy implants (OR = 7.14; p = .005). Furthermore, the likelihood was 6x greater in implants diagnosed with PI to exhibit moderate membrane thickening (OR = 6.75, p = .001). The patients receiving interventions aimed at arresting PI experienced significant enhancement in all radiographic parameters related to the sinus cavity at the 6-month follow-up (p < .001), though these variations were similarly independent of whether treatment consisted of PI treatment or implant removal. CONCLUSIONS: Maxillary sinus membrane thickening and the permeability/obstruction of the ostium are frequently associated with the presence of PI in posterior implants. Interventions targeting disease resolution effectively reduce membrane thickness to levels compatible with maxillary sinus health.

Immediate Implant Placement in the Aesthetic Area using Inverted Body-shift Design: A Prospective Clinical Pilot Study.

A prospective clinical pilot study was carried out to evaluate a novel macroimplant design with a 12° angled platform. The implant is placed at the center of the socket, optimizing all the alveolar bone. In addition, the prosthetic emergence should be ideal, as it is corrected and emerges through the cingulate area. Twelve patients were enrolled in an immediate implant placement procedure with immediate aesthetic rehabilitation to replace an anterior maxillary tooth, and were treated with inverted body-shift design with 12° angled neck. Only type I sockets according to the Elian classification were considered eligible for the study. There were no implant failures after one year of loading. Regarding the horizontal and vertical hard tissue changes, there was a statistically significant median overall horizontal change of -0.99 mm at 1 mm and of -0.61 mm at 3 mm. On the other hand, stability was observed at 5 mm, since the result obtained was not statistically significant. The median pink esthetic score (PES) at one year of follow-up was 11.5. This implant may be useful in the immediate tooth replacement treatment of maxillary anterior post-extraction sockets, nevertheless, comparative studies with conventional implants should be carried out.

On the feasibility of minimally invasive Le Fort I with patient-specific implants: Proof of concept.

A novel approach to Le Fort I osteotomy is presented, integrating patient-specific implants (PSIs), osteosynthesis and cutting guides within a minimally invasive surgical framework, and the accuracy of the procedure is assessed through 3D voxel-based superimposition. The technique was applied in 5 cases. Differences between the surgical plan and final outcome were evaluated as follows: a 2-mm color scale was established to assess the anterior surfaces of the maxilla, mandible and chin, as well as the condylar surfaces. Measurements were made at 8 specific landmarks, and all of them showed a mean difference of less than 1 mm. In conclusion, the described protocol allows for minimally invasive Le Fort I osteotomy using PSIs. Besides, although the accuracy of the results may be limited by the small sample size, the findings are consistent with those reported in the literature. A prospective comparative study is needed to obtain statistically significant results and draw meaningful conclusions.

Vascular Delay Soft Tissue Technique in Oral/Maxillary Bone Reconstructive Surgery: A Technical Note.

PURPOSE: The present study describes a new presurgical soft tissue technique in oral/maxillary bone reconstructive surgery for reducing the risk of soft tissue dehiscence and its related complications. MATERIALS AND METHODS: Ten consecutive patients with Cawood and Howell type V atrophy were scheduled for CAD/CAM titanium mesh bone reconstructive surgery after applying the vascular delay technique 21 days before regenerative surgery. The surgical and healing complications were clinically assessed at nine time points, ranging from the time of bone regenerative surgery to 9 months after surgery. Surgical complications included flap damage and neurologic and vascular complications. Healing complications were subdivided into four classes. These classes comprised Class I: small membrane exposure (≤ 3 mm) without purulent exudate; Class II: large membrane exposure (> 3 mm) without purulent exudate; Class III: membrane exposure with purulent exudate; and Class IV: abscess formation without membrane. RESULTS: The study sample included seven men and three women (mean age: 48.2 ± 3.5 years) with seven mandibular cases and three maxillary cases. The defect length ranged from three to six teeth, with a mean mesiodistal distance of 29.9 ± 8.5 mm and a mean volume augmentation of 2.03 ± 0.9 cm3. There were no surgical complications. One patient presented a Class I healing complication that did not affect the regeneration outcome. CONCLUSIONS: The vascular delay technique appears to reduce the risk of soft tissue dehiscence and exposure in bone regenerative surgery, though randomized studies involving larger samples and longer follow-up periods are needed in order to draw firm conclusions.

Effectiveness of virtual reality in relieving anxiety and controlling hemodynamics during oral surgery under local anesthesia: A prospective randomized comparative study.

It was the aim of the study to evaluate the contribution of a relaxing immersive experience with virtual reality (VR) goggles in reducing patient anxiety related to wisdom tooth extraction under local anesthesia. A prospective randomized comparative study in consecutive patients scheduled for bilateral wisdom tooth extraction under local anesthesia was carried out between March and December 2022. Both sides were operated upon in the same surgery, but on one side VR goggles were applied (VR), while on the other they were not (noVR). Anxiety was evaluated both subjectively (State-Trait Anxiety Inventory [STAI] and visual analogue scale [VAS]) and objectively (measuring heart rate, blood pressure [BP] and blood oxygen saturation) before (T1) and after each surgical step (T2VR and T2noVR). The study sample consisted of 27 patients: 9 men and 18 women, with an average age of 25.8 ± 6.5 years (range: 18-43). Anxiety as assessed by the STAI and VAS decreased from T1 to T2 (p < 0.001 and p < 0.001, respectively), although to a similar degree regardless of whether VR was used or not. Heart rate showed significant differences influenced by RV exposure (p = 0.013): it increased +2.5 ± 8.8 bpm in the control group and decreased -2.22 ± 7.55 bpm with VR (p = 0.013). Both minimum and maximum BP after surgery were significantly higher in the noVR group (p = 0.002 and p = 0.040, respectively). Regarding minimum BP, VR proved more effective among male patients (p = 0.057) and on starting the procedure using VR (p = 0.055). The results provided evidence of meaningful control of the hemodynamic variables, but less predictable performance in the subjective evaluation of anxiety.

Ultrasound-Guided Suprazygomatic Maxillary Nerve Block Is Effective in Reducing Postoperative Opioid Use Following Bimaxillary Osteotomy.

BACKGROUND: Ultrasound-guided maxillary nerve block has recently been described, though its impact upon bimaxillary osteotomy has not been formally investigated. PURPOSE: The present study was carried out to determine whether the addition of ultrasound-guided maxillary nerve block in subjects undergoing bimaxillary osteotomy reduces opioid use. STUDY DESIGN, SETTING, SAMPLE: A randomized clinical trial was carried out in adults undergoing bimaxillary osteotomy between April 2019 and January 2020 at Teknon Medical Center (Barcelona, Spain). PREDICTOR VARIABLE: The predictor variable was the treatment technique used (maxillary nerve block or no block). The subjects were randomized to either receive (test group) or not receive (control group) bilateral ultrasound-guided suprazygomatic maxillary nerve block (5 ml of 0.37% ropivacaine) before surgery. MAIN OUTCOME VARIABLE(S): The primary outcome variable was the intravenous methadone requirements in the first two postoperative hours. The secondary outcome variables were postoperative pain, rescue subcutaneous methadone, intravenous remifentanil used intraoperatively, the incidence of postoperative nausea-vomiting, and complications derived from maxillary nerve block. COVARIATES: Subject age, sex, weight, height, and anesthetic risk, and the duration of surgery were recorded. ANALYSES: Descriptive and inferential analyses were performed using the χ2 test and Mann-Whitney U test. Statistical significance was considered for P < .05. RESULTS: The baseline sample consisted of 68 subjects scheduled for bimaxillary osteotomy. The follow-up sample comprised 60 subjects: 30 in the control group (10 females and 20 males, aged 34.0 ± 10.2 years) and 30 in the test group (13 females and 17 males, aged 29.8 ± 10.8 years). The subjects who received maxillary nerve block showed less intravenous methadone use in the first 2 hours postsurgery (median 2.0 mg control group vs 0 mg test group; P < .001), lower pain levels at any time during the first 18 hours postsurgery (median visual analog score 4 control group vs 2 test group; P < .001), and a lesser percentage required methadone (33.3% control group vs 0% test group; P < .01) at 4-18 hours postsurgery. CONCLUSION AND RELEVANCE: The results obtained suggest that ultrasound-guided maxillary nerve block is a promising anesthetic technique capable of reducing intraoperative and postoperative opioid use, with greater patient comfort in bimaxillary osteotomy.

Surgery-first in interdisciplinary class II cases.

OBJECTIVES: To present an interdisciplinary case treated with a surgery-first orthognathic approach, followed by orthodontic and prosthodontic treatment. CLINICAL CONSIDERATIONS: After an accurate pre-operative virtual planning, a young patient with skeletal class II, retrognathia, and an anterior open bite was treated with bimaxillary orthognathic surgery without pre-surgical orthodontic decompensation. Orthodontic treatment was carried out post-operatively. The treatment was completed with a prosthodontic phase to improve the final esthetic outcome of the smile. CONCLUSIONS: A surgery-first approach allowed to achieve esthetic and functional results in a reduced treatment duration that remained stable over the course of 1 year. The outcomes were consistent with prior research in terms of advantages brought by following an accurately planned surgery-first protocol. Nevertheless, longer-term follow-up was required to evaluate the treatment stability. CLINICAL SIGNIFICANCE: An accurately planned surgery-first approach significantly helped in shortening the duration of the treatment, while providing a stable, functional, and esthetic solution to the patient's problems.

Guided Customization and Fixation of Allogenic Cortical Lamina in Alveolar Bone Regeneration. A Case Report.

Bone reconstruction surgeries such as the autogenous and allogenic shell techniques where cortical laminates are used to regenerate bone defects, requires time and expertise to adapt and fix the laminated cortical blocks onto the defect area. This case report illustrates the process of customizing and fixing an allogenic cortical laminate (ACL) to reconstruct a horizontal bone defect with guided surgical stents. Two types of surgical stents were designed: one to aid in cutting a prefabricated ACL into the desired shape for the defect to be regenerated, and the other type of stent, was used to assist in the positioning and fixation of the resulting laminates. These stents enabled the clinician to regenerate a horizontal defect with reduced surgical time, increased precision and safety during laminate fixation. After 5 months of healing a dental implant could be placed in the regenerated site. The use of surgical stents in this type of bone regeneration surgeries can be helpful specially in more complex bone defects where precision is key. Further clinical studies are needed to validate this technique.

Bilateral sagittal split osteotomy with or without concomitant removal of third molars: a retrospective cohort study of related complications and bone healing.

PURPOSE: To carry out a comparative evaluation of the intra- and postoperative complications, and bone healing, following bilateral sagittal split osteotomy (BSSO) with or without concomitant removal of third molars. MATERIAL AND METHODS: A retrospective analysis was performed of two cohorts subjected to BSSO with the intraoperative removal of third molars (test group) versus the removal of third molars at least 6 months prior to BSSO (control group), comprising at least 1 year of clinical and radiographic follow-up. Partially or completely erupted third molars were extracted immediately before completing the osteotomy, whereas impacted third molars were removed after the osteotomy had been performed. Hardware reinforcement was performed in bimaxillary cases where concomitant molar extraction impeded placement of the retromolar bicortical screw of the hybrid technique. RESULTS: A total of 80 surgical sites were included (40 in each group). Concomitant extraction of the molar represented a mean increase in surgery time of 3.7 min (p < 0.001). No additional complications occurred in the test group (p = 0.476). The gain in bone density was preserved in both groups (p = 0.002), and the increase was of the same magnitude in both (p = 0.342), despite the fact that the immediate and final postoperative bone densities were significantly higher in the control group (p = 0.020). CONCLUSION: The results obtained support concomitant molar extraction with BSSO as a feasible option.

Does Aesthetic Osseous Genioplasty Impact Upper Airway Volume?

BACKGROUND: Although maxillomandibular advancement is the treatment of choice for obstructive sleep apnea syndrome (OSAS) in the presence of underlying maxillomandibular complex hypoplasia, there is still a gap in the literature regarding the impact of genioplasty upon upper airway volume (UAV). OBJECTIVES: The aim of this study was to evaluate the impact of isolated osseous genioplasty upon UAV. METHODS: A retrospective analysis of all patients subjected to isolated osseous genioplasty between July 2015 and July 2022 was conducted. Cone-beam computed tomography was performed preoperatively and postoperatively to assess the chin and hyoid 3-dimensional (3D) spatial position and UAV changes after surgery. RESULTS: A total of 44 patients were included in the study. Regarding surgical movements of the chin, almost all patients received a sagittal movement (n = 42; 39 forward and 3 backward), while in 8 patients a vertical movement (5 upward and 3 downward) was applied, and in 6 patients the chin was centered. Statistically significant increases in total UAV (P = .014) and at the level of the oropharynx (P = .004) were observed. Specifically, chin centering, upward and forward movements enlarged the oropharynx volume (P = .006, .043 and .065, respectively). Chin advancement enlarged the hypopharynx volume (P = .032), as did upward movement of the hyoid bone (P < .001). CONCLUSIONS: Results of the study suggest that aesthetic osseous genioplasty impacts the UAV: each 3D spatial chin movement differently impacts the upper airway by enlarging or narrowing it. However, further studies addressing the apnea-hypopnea index are required to assess its effectiveness in treating OSAS.

Three-Dimensional Evaluation of the Accuracy of Zygomatic Implant Placement Through an In-House Fully Guided Approach.

Purpose: To validate guided surgery for zygomatic implants (ZIs) by analyzing the final position of the implants relative to the preoperatively planned position. Material and Methods: Five patients with fully edentulous atrophic maxillae treated with four ZIs through a fully guided implant surgical approach were evaluated. The preoperative phase included digital planning, through which the surgical guide was designed and created. Analysis of the guided surgery accuracy was carried out by superimposing the digital planning over the final position of the implants using preoperative and postoperative CBCT. The radiologic evaluation included implant angular deviation, entrance deviation, exit deviation, platform deviation, and apex apicocoronal and mesiodistal deviation. Results: All five patients (two men and three women; mean age: 61.8 ± 3 years) were each treated with four ZIs using a fully guided approach with an extrasinusal path, obtaining ideal emergence of the implants. Superimposition comparison found a mean axial angular implant deviation of 0.79 ± 0.41 degrees and a mean implant entrance deviation of 0.95 ± 0.26 degrees. The platform deviation was 0.62 ± 0.19 mm buccopalatally and 0.76 ± 0.14 mm mesiodistally, while the apical deviation was 0.42 ± 0.13 mm buccopalatally and 1.06 ± 0.37 mm mesiodistally. Conclusions: Guided surgery in zygomatic implants appears to be sufficiently accurate to make it a safe and predictable technique.

Dental Implant Positioning Accuracy Using a Key or Keyless Static Fully Guided Surgical System: A Prospective Systematic Review and Meta-Analysis.

PURPOSE: To realize a systematic review with prospective meta-analysis aiming to compare the accuracy of static fully guided implant placement depending on the drill key modality (conventional drill key surgery systems versus newer keyless systems) and evaluate the impact of deviations factors. MATERIALS AND METHODS: An electronic systematic search was conducted to identify prospective clinical trials matching inclusion criteria. The variables of interest were coronal global, apical, vertical, and angular deviations. The types of edentulism, and surgical guide support were investigated as deviation factors. Meta-regression (mixed-effect model) was performed. Heterogeneity was assessed using Cochrane's I² test and interpretation thresholds. RESULTS: A total of 1233 implants in 475 patients were analyzed (18 studies included). Coronal global deviation was significantly lower in the keyless group than in the key group (-0.36 mm; 95% confidence interval [CI] -0.62, -0.09; p=0.008). Angulation control of the keyless system was superior to that of the key system (-0.36 degrees; 95% CI -0.75, 0.02; p=0.063). Non-significant differences were found between both groups in apical (p=0.684) and vertical deviations (p=0.958). Significant influence of the type of edentulism (single, partial, total) and surgical guide support (tooth, mucosa, bone) on the overall amount of coronal global, apical, and angular deviations was found (p<0.001). Lowest deviations were found in partial edentulism and tooth-supported surgical guide groups. (p<0.001). CONCLUSION: Keyless static fully guided surgical systems allowed significantly better control of coronal and angular deviations than conventional systems. The types of edentulism and surgical guide support seemed to influence the positioning accuracy.

Dynamic Implant Surgery-An Accurate Alternative to Stereolithographic Guides-Systematic Review and Meta-Analysis.

(1) Background: Dynamic guided surgery is a computer-guided freehand technology that allows highly accurate procedures to be carried out in real time through motion-tracking instruments. The aim of this research was to compare the accuracy between dynamic guided surgery (DGS) and alternative implant guidance methods, namely, static guided surgery (SGS) and freehand (FH). (2) Methods: Searches were conducted in the Cochrane and Medline databases to identify randomized controlled clinical trials (RCTs) and prospective and retrospective case series and to answer the following focused question: "What implant guidance tool is more accurate and secure with regard to implant placement surgery?" The implant deviation coefficient was calculated for four different parameters: coronal and apical horizontal, angular, and vertical deviations. Statistical significance was set at a p-value of 0.05 following application of the eligibility criteria. (3) Results: Twenty-five publications were included in this systematic review. The results show a non-significant weighted mean difference (WMD) between the DGS and the SGS in all of the assessed parameters: coronal (n = 4 WMD = 0.02 mm; p = 0.903), angular (n = 4 WMD = -0.62°; p = 0.085), and apical (n = 3 WMD = 0.08 mm; p = 0.401). In terms of vertical deviation, not enough data were available for a meta-analysis. However, no significant differences were found among the techniques (p = 0.820). The WMD between DGS and FH demonstrated significant differences favoring DGS in three parameters as follows: coronal (n = 3 WMD = -0.66 mm; p =< 0.001), angular (n = 3 WMD = -3.52°; p < 0.001), and apical (n = 2 WMD = -0.73 mm; p =< 0.001). No WMD was observed regarding the vertical deviation analysis, but significant differences were seen among the different techniques (p = 0.038). (4) Conclusions: DGS is a valid alternative treatment achieving similar accuracy to SGS. DGS is also more accurate, secure, and precise than the FH method when transferring the presurgical virtual implant plan to the patient.

Narrow diameter titanium-zirconium tissue-level implants supporting multi-unit FDPs in the anterior area: A 5-year prospective study.

BACKGROUND: Narrow diameter implants (NDIs) are used in cases of limited mesio-distal space, or if the alveolar ridge does not allow placement of a standard diameter implant. PURPOSE: The aim of this prospective case series study is to present the 5-year clinical-, radiological-, and patient-reported outcome measures (PROMs) of patients with partial edentulism in the anterior area of the jaws requiring the placement of two narrow diameter implants to support a 3- or 4-unit fixed partial denture (FPD). MATERIALS AND METHODS: Thirty partially edentulous patients missing 3 or 4 adjacent teeth in the anterior area of the jaws were included in the study. Two titanium-zirconium tissue-level NDIs were placed in each patient in healed anterior sites (60 implants). A conventional loading protocol was performed to provide a FPD. Implant survival, success, marginal bone-level changes (MBL), clinical parameters, buccal bone stability with CBCT, adverse events and PROMs were recorded. RESULTS: The survival and success rates for the implants were 100%. The mean MBL (±SD) after prosthesis delivery, and 5-year follow-up (mean 58.8 months; range: 36-60) was 0.12 ± 0.22 and 0.52 ± 0.46 mm, respectively. Decementation and screw loosening were the most frequent prosthetic complications, yielding a prosthetic survival and success rates of 100% and 80%, respectively. Patient satisfaction was high with a mean (±SD) score of 89.6 ± 15.1. CONCLUSIONS: The use of tissue-level titanium-zirconium NDIs supporting splinted multi-unit FPDs in the anterior area seems to be a safe and predictable treatment option after a 5-year follow-up period.

Accuracy of Orthognathic Surgical Planning using Three-dimensional Virtual Techniques compared with Conventional Two-dimensional Techniques: a Systematic Review.

Objectives: The objective was to assess the accuracy of orthognathic surgical planning using three-dimensional virtual planning compared with conventional two-dimensional planning. Material and Methods: MEDLINE (PubMed), Embase and Cochrane Library search combined with hand-search of relevant journals was conducted to identify randomized controlled trials (RCTs) published in English through August 2nd, 2022. Primary outcomes included postsurgical accuracy of hard and soft tissue. Secondary outcomes included treatment planning time, intraoperative time, intraoperative blood loss, complications, financial expenses, and patient-reported outcome measures (PROMs). Quality and risk-of-bias assessment were evaluated by Cochrane risk of bias tool and GRADE system. Results: Seven RCTs characterised by low, high, and unclear risk of bias fulfilled inclusion criteria. Included studies disclosed conflicting results regarding accuracy of hard and soft tissue as well as treatment planning time. The intraoperative time was shortened, and financial expenses were increased with three-dimensional virtual surgical planning (TVSP), while no planning-related complications were revealed. Comparable improvement in PROMs were reported with TVSP and two-dimensional planning. Conclusions: Future orthognathic surgical planning will indisputable be performed by three-dimensional virtual planning. The financial expenses, treatment planning time, and intraoperative time will therefore probably decrease due to further development of three-dimensional virtual planning techniques. The hard and soft tissue accuracy between planned position and achieved surgical outcome seems to be improved by three-dimensional virtual planning compared with two-dimensional planning, although results are inconsistent. Further development of three-dimensional virtual planning involving cutting guides and patient-specific osteosynthesis plates are therefore needed to improve the accuracy of orthognathic surgical planning.

Orthognathic surgery and aligners. A comparative assessment of periodontal health and quality of life in postsurgical orthodontic treatment with aligners versus traditional fixed appliances: a randomized controlled trial

Background: Removable clear aligners have become very popular in the last few decades, but they are still little used in the field of orthognathic surgery (OS). The objective of this study was to compare periodontal health and quality of life (QoL) associated to postsurgical orthodontic treatment. Material and methods: Patients with dentofacial deformities undergoing OS were randomly allocated to receive postsurgical orthodontic treatment with either fixed orthodontic appliances or Invisalign. The main outcomes were periodontal health and QoL. Plaque index, probing depth and bleeding on probing were assessed as periodontal health indicators. QoL was assessed through the Orthognathic Quality of Life Questionnaire (OQLQ-22) and the Oral Health Impact Profile (OHIP-14). Data were analyzed before surgery and end of treatment. Total duration of treatment was also recorded. Results: Twenty-eight patients were randomized, (16 women, 12 men). Periodontal assessment showed better outcomes for the Invisalign group: bleeding on probing (p=0.013), plaque index (p=0.001) and probing depth (p<0.001). The QoL questionnaires showed significant differences in favor of the Invisalign group: OHIP-14 (p=0.004) and OQLQ-22 (p=0.002). Total duration of treatment was similar in both groups (p=0.575). Conclusions: Compared to traditional orthodontics with fixed appliances, patients managed with clear aligners after OS (surgery-first approach) had better periodontal health and QoL outcomes. (AU)

Fat grafting in patients with cleft lip and palate: A systematic review.

This systematic review aims to compare different fat-grafting techniques for cleft lip and palate repair. A search was conducted in PubMed, Embase, Cochrane Library, gray literature and reference lists of selected articles. A total of 25 articles were included, 12 on closure of palatal fistula and 13 on cleft lip repair. The rate of complete resolution of palatal fistula ranged from 88.6% to 100% in studies with no control group, whereas in comparative studies patients receiving a fat graft showed better outcomes than those not receiving a graft. Evidence suggests that fat grafting can be indicated for the primary and secondary repair of cleft palate, with good results. The use of dermis-fat grafts in lip repair was associated with gains in surface area (11.5%), vertical height (18.5%-27.11%), and lip projection (20%). Fat infiltration was associated with increased lip volume (6.5%), vermilion show (31.68% ± 24.03%), and lip projection (46.71% ± 31.3%). The available literature suggests that fat grafting is a promising autogenous option for palate and fistula repair and for improvement of lip projection and scar aesthetics in patients with cleft. However, to develop a guideline, further studies are needed to confirm whether one technique is superior to the other.

Influence of Insertion Torques on the Surface Integrity in Different Dental Implants: An Ex Vivo Descriptive Study.

BACKGROUND: The primary objective of this ex vivo study was to assess the influence of increasing insertion torques on three types of dental implants and possible alterations of their microgeometry after the application of three different torque intensities. METHODS: 27 implants of 3 different implant brands (Groups A, B and C) were placed in cow ribs using 30 Ncm, 45 Ncm and 55 Ncm insertion torques. The implants were subsequently removed using trephine burs, and SEM analysis was carried out in order to detect implant surface and connection changes, as compared to the implant controls. RESULTS: Surface deformations were predominantly observed on the third apical part of the implants. The alterations presented with increasing insertion torques, with 45 Ncm being the threshold value. Prosthetic connections were also compromised. CONCLUSIONS: The changes sustained by the implants were proportional to the insertion torque they were subjected to; 45 Ncm and greater insertion torques resulted in more consistent damage, both on the implant surface and the implant connection.

Definition of New Three-Dimensional Cephalometric Analysis of Maxillomandibular Sagittal Relationship for Orthodontics and Orthognathic Surgery: Normative Data Based on 700 CBCT Scans.

The objective of the study was to define the norm of new 3-dimensional cephalometric analysis of maxillomandibular sagittal relationship with the patient in Natural Head Position. A cross-sectional study was performed using 700 consecutives cone beam computed tomography datasets of pre-orthodontic patients received for three-dimensional craniofacial analysis. To stablish the clinical norm of the new sagittal reference (linear distance A-B), the correlation with the gold standard (ANB angle) was estimated with the Pearson's correlation coefficient. Subsequently, the prognostic values of the linear distance A-B was calculated to define the clinical norm. The sample was composed by 463 women (66.1%) and 237 men (33.9%). The mean age was 30 ± 14,5 years old (range 6-71 y old). According to the skeletal class classification (ANB), 46.1% (323) were class I, 42% (294) class II, and 11.9% (83) class III. The regression model found that each additional grade of the ANB angle imply a mean increase of 1.24 mm of the distance A-B ( P <0.001). The normative value of the linear distance A-B was obtained through the prognostic values of the distance for the limits of the ANB norm 0 to 4. These values were on the range of 0.52 to 5.48 mm. Therefore, the clinical norm for cephalometric maxillomandibular sagittal relationship using linear distance from point A-B is: 3±2.48 mm. With this new approach, we can define the skeletal sagittal relationship of the patient in natural head position overcoming the limitations of using intracranial or occlusal plane references improving the diagnosis and orthognathic surgical planning process.

Barcelona line. A multicentre validation study of a facial projection reference in orthognathic surgery.

The purpose of this study was to validate an already published facial anteroposterior reference: upper incisor (UI) to soft tissue plane or so-called Barcelona line (BL) to trace the most aesthetic sagittal position of the maxilla. A cross-sectional multicentre evaluation of Caucasian patients from Spain and Brazil with different anteroposterior maxillary positions was designed. Sagittal images in natural head orientation of grouped patients according to the horizontal distance from the UI to BL were ranked by healthcare professionals and non-professional Caucasian raters according to the aesthetic perception of each profile, using a digital survey. Seventy-four raters (50 laypeople, 12 orthodontists, and 12 maxillofacial surgeons) rated 40 profiles. The best-rated profile corresponded to group 3 (0-4 mm UI-BL) with 61.8% of positive evaluations, followed by group 4 (≥ 4 mm UI-BL): with 61.1%. On the other hand, group 1 (≤-4 mm UI-BL) was the worst-ranked profile with 71.8% of negative evaluations, followed by group 2 (-4-0 mm UI-BL): with 59.6% of negative evaluations. The correlation between the mean assessment score and UI-BL showed a moderately-strong association (r = 0.68, p < 0.001). The inter-rater reliability of assessment (74 evaluators) was moderate (k = 0.49, 95% CI: 0.39 to 0.59). The results suggest that protrusive middle-third facial profiles are preferable. The BL is proposed as a simple, individualised, and reproducible tool to trace an aesthetic sagittal position of the maxilla in orthognathic surgery.