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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. 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.

Objectives: A systematic review was performed to analyze the current evidence on three-dimensional (3D) computed tomography (CT) superimposition protocols used to assess dentomaxillofacial changes after orthognathic and orthofacial surgery. Accuracy, reproducibility, and efficiency were evaluated. Methods: The search was divided into Main Search (PubMed, EMBASE, Cochrane Library, LILACS, and SciELO), Grey Literature search (Google Scholar and Open Grey), and Manual search. Thirteen studies were included. Of these, 10 reported data on accuracy, 10 on reproducibility and five on efficiency. Seven proposed or evaluated methods of voxel-based superimposition, three focused on the surface-based technique, one compared surface- and voxel-based superimposition protocols, one used the maximum mutual information algorithm, and one described a landmark-based superimposition method. Cone-beam computed tomography (CBCT) was the most common imaging technique, being used in 10 studies. Results: The accuracy of most methods was high, showing mean differences smaller than voxels’ dimensions, ranging between 0.05 and 1.76 mm for translational accuracy, and 0.10–1.09° for rotational accuracy. The overall reproducibility was considered good as demonstrated by the small mean error (range: 0.01–0.26 mm) and high correlation coefficients (range: 0.53–1.00). Timing to complete virtual superimposition techniques ranged between a few seconds up to 40 min. Conclusions: Voxel-based superimposition protocols presented the highest accuracy and reproducibility. Moreover, superimposition protocols that used automated processes and involved only one software were the most efficient.

The purpose of this study was to evaluate maxillary expansion, operative time and pain associated with a new minimally invasive surgical technique to treat maxillary hypoplasia in adult patients. Consecutive patients were included and prospectively analyzed. The technique consists in miniscrew-assisted rapid palatal expansion (MARPE), minimally invasive approach to maxillary osteotomies, latency period and activation period until the desired expansion. The parameters evaluated included operative time, treatment-related pain by the visual analog scale (VAS), and transverse maxillary expansion. The Shapiro-Wilk test was used to assess the normality of data distribution. A paired t-test was used to compare the data between T0 (preoperative) and T1 (postoperative - end of activation). The significance level was set at 5%. Eleven patients were included. Mean operative time was 24.11 min (14.4-32 min) and overall postoperative VAS score was 2.81 (0-9). A comparative analysis showed significant increases in maxillary width at the skeletal, alveolar, and dental levels (p 0.0001 for all), with a mean range of 1.8 (SD 0.3) mm to 4.7 (SD 0.5) mm. The present minimally invasive surgical MARPE (MISMARPE) technique appears to yield good skeletal outcomes with minimal trauma. It might have potential for clinical use, but larger comparative studies are needed to confirm the clinical relevance of the approach.

To describe the benefits of covering the extrasinusal length of extramaxillary zygomatic implants with a pedicled buccal fat pad flap through a tunnel approach.Four extramaxillary zygomatic implants were placed in 10 patients and loaded immediately with an acrylic provisional fixed prosthesis. The extrasinusal length of every implant was covered with a pedicled buccal fat pad flap. Study variables were implant survival rate, peri-implant soft tissue recession (PISTR), peri-implant soft tissue condition (PISTC), modified Bleeding Index (mBI), and suppuration. The statistical analysis comprised the Brunner-Langer model of longitudinal data for each variable and the analysis of variance to assess main effects and interactions.All the zygomatic implants showed osseointegration, resulting in a survival rate of 100%. The PISTR was evaluated after surgery (T0) and after 12 months (T1), statistically significant differences being observed (P = .014). Recession also depended on specific implant positioning; zygomatic implants in the anterior were found to have a higher risk of recession vs implants in the posterior (P = .065). The PISTC was assessed at T0 and T1, and no statistically significant changes were observed (P = .718). Bleeding on probing was present in 10% of the implants at T0 and in 15% at T1, the difference being nonsignificant (P = .317).The use of a pedicled buccal fat pad flap to cover the extrasinusal length of extramaxillary zygomatic implants appears to reduce the risk of soft tissue recession and exposure of the implant surface to the oral cavity.

Purpose The aim of this study was to evaluate the nasolabial soft tissues effects in three different Le Fort I osteotomy techniques using cone beam computed tomography (CBCT) evaluation of three-dimensional (3D) volume surfaces. Materials and methods A retrospective study was designed, and three groups were evaluated: group 1, patients who underwent conventional Le Fort I osteotomy; group 2, patients who underwent subspinal Le Fort I osteotomy; and group 3, patients who underwent conventional Le Fort I osteotomy with ANS recontouring or removal. CBCT evaluation was performed at two time points: T0, 1 week before surgery; T1, 6 months after surgery. Results A total of 90 patients were enrolled in this study (group 1: 30; group 2: 30; group 3: 30). Mean maxillary advancement was 4.26 mm. For group 1, mean change in inter-alar width was 2.29 ± 1.57 mm (minimum -2mm; maximum 6.1 mm; for group 2 it was 1.20 ± 1.56 mm (minimum −1.7 mm; maximum 5.9 mm), and for group 3 was 1.84 ± 1.76 mm (minimum −2.3 mm; maximum 5.9 mm). For group 1, mean change in alar base width was 1.69 ± 2.32 mm (minimum −4.8 mm; maximum 6,1 mm); in group 2 it was 0.85 ± 2.08 mm (minimum -4mm; maximum 6 mm), and group 3 was 1.21 ± 1.83 mm (minimum -2mm; maximum 5 mm). Results showed statistically significant differences in nasolabial area (P Conclusion Results point to a better control of nasal tip projection, interalar and alar base width as well as upper lip form and function when comparing subspinal Le Fort I osteotomy and conventional techniques. This technique should be chosen when these changes in nasolabial region are to be avoided.

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. 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.

OBJECTIVE A cohort prospective study was conducted to assess the three-dimensional positioning accuracy of the implant between pre-surgical and the final implant position using a static fully guided approach in the posterior area of the jaws. MATERIALS AND METHODS A total of 60 implants (30 patients) were digitally analyzed after superimposing the Digital Imaging and Communications in Medicine (DICOM) files obtained from the Cone Beam Computed Tomography (CBCT) pre- and post-implant placement. The software calculations included deviations at the implant shoulder and at the implant apex, global deviation (3D offset), and angle deviation. Statistical analysis was performed with α = 0.05. RESULTS Considering the total number of implants, mesiodistal, buccolingual, and apicocoronal mean deviations at the shoulder and implant apex were equal or below 0.21 ± 0.69 mm, and only the buccolingual mean deviation at the apex reached up to 0.67 ± 1.06 mm. The mesiodistal and apicocoronal deviations were not statistically significant at both the shoulder and apex levels of the implant. The mean total angular deviation was 5.62° ± 4.09. The main limitation of this surgical approach was the requirement for a wide mouth opening. CONCLUSIONS Static fully guided surgery for dental implant placement exhibits minimum deviations respect to presurgical planning. The main limitation in the posterior areas is the requirement for a wide mouth opening. CLINICAL RELEVANCE Even with minimum deviations clinically acceptable, precautions and safety margins must be respected when using static full-guided surgery to place dental implants.

Healing complications in guided bone regeneration (GBR) can be frequent when nonresorbable membranes are used. Exposure of dense polytetrafluoroethylene (d-PTFE) membranes to the oral cavity are usually located close to the incision line due to a lack of tension-free flap closure. This case report presents a safe, novel technique that uses d-PTFE membranes placed on the missing buccal and palatal bone walls without covering the coronal aspect of the regeneration. Therefore, these membranes can be kept away from the incision line to minimize the risk of exposure. The coronal part is then covered with a resorbable membrane. A clinical case is presented, using this novel technique to three-dimensionally reconstruct noncontained defects in the maxilla. This technique is safe and effective in regenerating these defects; after 8 months of healing, three implants could be placed with proper primary stability. Further, histologic and histomorphometric analyses revealed functional bone with areas of new bone formation. However, more long-term studies are required to validate this technique.

Currently, the wish to optimize facial esthetics-in the context of a dysfunctional occlusion or not-has become the main motivation for orthognathic surgery in many cases. In this context, considering that protrusive faces are advised more attractive and that the lack of skeletal support accelerates the aging process, orthognathic surgery will mostly involve a forward movement of the maxillamandibular complex..

A systematic review search was based on the PICOS approach, as follows: population: cleft lip and palate patients; intervention: Le Fort I osteotomy; comparator: different surgical protocols; outcome: stability, recurrence or surgical complications; study designs: only case reports were excluded from the review. No restrictions were placed on language or year of publication. Risk of bias was analyzed, heterogeneity was assessed, and subgroup analysis was performed using a level of significance of 1% (p = 0.01). The search identified 248 citations, from which 29 studies were selected and a total of 797 patients enrolled. The level of agreement between the authors was considered excellent (k = 0.810 for study selection and k = 0.941 for study eligibility). Our results reported a mean maxillary advancement of 5.69 mm, a mean vertical downward/upward of 2.85/−2.02 mm and a mean clockwise rotation of 4.15°. Greater surgical relapse rates were reported for vertical downward movement (−1.13 mm, 39.6%), followed by clockwise rotation (−1.41°, 33.9%), sagittal (−0.99 mm, 17.4%) and vertical upward (0.11 mm, 5.4%) movements. No relevance was found regarding the type of cleft, the type of Le Fort I osteotomy, concomitant bone grafting, surgical overcorrection, postoperative rigid or elastic intermaxillary fixation, or retention splint. Study limitations were heterogeneity and the low number of high-quality studies. In spite of reported high relapse rates, Le Fort I osteotomy for maxillary reposition is the first-choice procedure for selected cleft lip and palate patients in whom extensive maxillary movements are not required, because of its safety and its three-dimensional movement versatility in one-step surgery. Otherwise, distraction osteogenesis should be considered as the gold standard treatment.

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.

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. info:eu-repo/semantics/publishedVersion

The main objective was to evaluate the accuracy of dynamic navigation-guided surgery (DNGS) for implant positioning performed by a novice operator. The secondary objectives were to analyze the operator's learning curve and identify possible complications deriving from the technique.Twenty-five implants were placed in eight partially edentulous human heads. Preoperative CBCT scans were imported to planning software to determine the implant positions. Implants were placed using a dynamic navigation system. Postoperative CBCTs were superimposed onto the implant planning images. Discrepancies between the virtually planned implant positions and the postoperative positions were evaluated by measuring horizontal platform deviation, apex deviation, apicocoronal (vertical) deviation, and angular deviation.Mean platform, apex, vertical, and angle deviations were 1.55 ± 0.81 mm, 2.45 ± 0.84 mm, 1.59 ± 0.70 mm, and 5.56 ± 4.03 degrees, respectively. No significant differences were found between the maxilla and mandible or between anterior and posterior sites. A flat learning curve was observed, with the exception of the implant platform, where a tendency toward improvement in accuracy was observed between the 8th and the 17th implant placed. No complications were reported.Based on the results of a study performed by a novice operator on a cadaveric model, DNGS allows accurate implant placement within a 2-mm safety margin in terms of implant platform and vertical positions, and a 3-mm margin in apical vicinities. The technique requires practice to learn the required eye-hand coordination. (Int J Comput Dent 2022;25(4):377-0; doi: 10.3290/j.ijcd.b2588207).

Orthognathic surgery, as part of maxillofacial surgery, involves the correction of dentofacial deformities for both functional (occlusion, speech and sleep disturbances) and aesthetic reasons. Deformities of this kind affect between 5–10% of the general population. The underlying causes are not clear, though genetic, environmental and embryonic factors have been suggested to play a role (1). The surgical techniques used are complex, with osteotomies of the mandible and upper maxilla that allow three-dimensional displacements of both bone structures with the purpose of aligning the facial axes. info:eu-repo/semantics/publishedVersion