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Objective The aim of this study was to analyse the correlation between incisor alveolar bone thickness (IABT) and dentofacial characteristics or age in adult female patients with bimaxillary dentoalveolar protrusion (BDP). Evaluating the contribution of these characteristics may help to predict the IABT differences in this patient population. Setting and sample population A retrospective study whose sample comprised 80 pretreatment adult female patients with BDP (mean age 24.6 years). Materials and methods The IABT of the bimaxillary central incisors was measured by cone-beam computed tomography. Among the types of IABT, the apical trabecular bone thickness was measured with a quantitative method. The sagittal skeletal pattern, facial divergence, the incisor inclination angle, and mandibular plane angulation were determined by cephalometric analysis. A backward linear multiple regression was performed to analyse the associations between IABT and these characteristics. Results Three dentofacial traits and age were associated with IABT. Patients with increased age and facial divergence tended to have a thinner mandibular incisor bone support, while increased root length was associated with a thicker mandibular incisor apical bone thickness. Increased U1-SN and facial divergence may lead to a thinner maxillary incisor palatal bone, while increased U1-SN resulted in a thicker maxillary incisor labial bone. Conclusions The bony support of the incisors is associated with age and dentofacial traits. Increasing age and facial divergence are considered risk factors for alveolar defects in female patients with BDP. In contrast, increased root length is associated with a thicker mandibular incisor apical bone support.

Background: Analyze the palatal bone thickness of maxillary skeletal expander (MSE) implantation area in adult patients with skeletal class Ⅲ malocclusion based on Cone-beam computed tomography (CBCT) data, and to provide a reference for the implantation of the miniscrew.Methods: A total of 80 adult patients (40 M, 40 F) with an normal angle before treatment were divided into two groups; skeletal class Ⅲ malocclusion group and skeletal Ⅰ malocclusion group according to sagittal facial type, with 40 patients in each group, with a male to female ratio of 1: 1. CBCT scanner was used to obtain DICOM data from all patients.The palatal bone thickness was measured at 45 sites with MIMICS 21.0 and SPSS 22.0 was employed for statistical analysis. The bone thickness of different regions of the palate in the same group was analyzed by one-way analysis of variance (ANOVA) method; Fisher’s least significant difference (LSD)-t method was used for comparison in pairs, and an independent sample t-test was employed to test the difference of bone thickness in the same area between the two groups.Results: (1) There was no significant difference among the anterior, middle, and posterior regions of the midline area in patients with skeletal class Ⅲ malocclusion (P > 0.05). Palatal bone thickness decreased gradually from front to back in the middle and lateral areas in both groups (P < 0.001). (2) The bone thickness of the anterior, middle, and posterior regions of the two groups gradually decreased from the middle area to the parapalatine region. (3) The palatal bone were significant thinner in the area 9.0 mm before the transverse palatine suture in midline area, 9.0 mm before and after the transverse palatine suture in the middle area, and 9.0 mm after the transverse palatine suture in the lateral area.Conclusion: (1) The palatal bone of patients with class Ⅲ malocclusion was thinner in some areas, so the MSE implant anchorage position could be moved forward appropriately. (2) The thin palatal bone increased the risk of MSE anchorage screw penetrating nasal mucosa and even inferior turbinate. Patients should be given a more precise and personalized implantation scheme based on factors such as palatine bone thickness and palatal morphology.

Background and Objective: Quantitative assessment of bone density and thickness in computed-tomography images offers great potential for preoperative planning procedures in robotic ear surgery. Methods: We retrospectively analyzed computed-tomography scans of subjects undergoing cochlear implantation (N = 39). In addition, scans of Thiel-fixated ex-vivo specimens were analyzed (N = 15). To estimate bone mineral density, quantitative computed-tomography data were obtained using a calibration phantom. The temporal bone thickness and cortical bone density were systematically assessed at retroauricular positions using an automated algorithm referenced by an anatomy-based coordinate system. Two indices are proposed to include information of bone density and thickness for the preoperative assessment of safe screw positions (Screw Implantation Safety Index, SISI) and mass distribution (Column Density Index, CODI). Linear mixed-effects models were used to assess the effects of age, gender, ear side and position on bone thickness, cortical bone density and the distribution of the indices. Results: Age, gender, and ear side only had negligible effects on temporal bone thickness and cortical bone density. The average radiodensity of cortical bone was 1,511 Hounsfield units, corresponding to a bone mineral density of 1,145 mg HA/cm3. Temporal bone thickness and cortical bone density depend on the distance from Henle's spine in posterior direction. Moreover, safe screw placement locations can be identified by computation of the SISI distribution. A local maximum in mass distribution was observed posteriorly to the supramastoid crest. Conclusions: We provide quantitative information about temporal bone density and thickness for applications in robotic and computer-assisted ear surgery. The proposed preoperative indices (SISI and CODI) can be applied to patient-specific cases to identify optimal regions with respect to bone density and thickness for safe screw placement and effective implant positioning.

Objective: Facial alveolar bone (FAB) thickness has clinical importance because of the effect on implant placement, mucogingival surgery, and dimensional changes of the socket after extraction. The study aims to evaluate the FAB thickness of endodontically treated maxillary first and second molars using cone-beam computed tomography (CBCT).Method: Sixty-eight CBCT images were retrospectively scanned and 42 three-rooted maxillary molars (21 first and 21 second molars) were selected. Furcation and periapical lesion, root resorption, post-core restoration, periodontal loss, and previous orthodontic 104 treatment were excluded from the study. FAB thicknesses of mesial and distal roots were measured at the bone crest, 6 mm from the bone crest, and the apical level of the root. Images were viewed on the coronal, axial, and sagittal plane in CBCT at x5 magnification. The statistical analysis was performed.Results: FAB thicknesses of mesial and distal roots of endodontically-treated first molar were 0,64 and 0,74 mm at the bone crest and 0,43 and 0,88 mm at 6 mm from the bone crest and 0,80 and 1,02 mm at apical level, respectively. For the second molar, 0,97 and 1,25 mm at the bone crest and 1,53 and 1,41 mm at 6 mm from the bone crest and 1,78 and 1,34 mm at apical level, respectively. Mann-Whitney U test showed that there is no statistically significant difference between the FAB thickness of endodontically-treated and healthy maxillary first and second molars.Conclusion: This study concluded that there is no influence of the presence of endodontic treatment on the FAB thickness of maxillary molars. Amaç: Bukkal alveoler kemiği kalınlığı, implant yerleştirme, mukogingival cerrahi ve çekim sonrası soketin boyutsal değişiklikleri üzerindeki etkisi nedeniyle klinik öneme sahiptir. Bu çalışmanın amacı; endodontik tedavili maksiller molar dişlerdeki fasiyal alveoler kemik kalınlığının dental volümetrik tomografi (DVT) kullanarak incelenmesidir.Yöntem: Altmış sekiz DVT görüntüsü retrospektif olarak tarandı ve 42 üç köklü maksiller molar (21 birinci ve 21 ikinci molar) seçildi. Furkasyon ve periapikal lezyonu, kök rezorpsiyonu, post-core, periodontal kayıp ve ortodontik tedavili dişler çalışma dışı bırakıldı. Mezial ve distal köklerin fasiyal alveolar kemik kalınlıkları kemik krestinden, kemik krestinden 6 mm yukardan ve kökün apikal seviyesinden ölçüldü. Görüntüler CBCT'de x5 büyütmede koronal, aksiyel ve sagital düzlemde incelendi. İstatistiksel analiz yapıldı.Bulgular: Endodontik tedavili birinci moların mezial ve distal köklerinin kemik kalınlıkları kemik krestinde 0,64 ve 0,74 mm, kemik krestinden 6 mm'de 0,43 ve 0,88 mm ve apikalde 0,80 and 1,02 mm olarak ölçüldü. İkinci molar için kemik tepesinde 0,97 ve 1,25 mm, kemik tepesinden 6 mm'de 1,53 ve 1,41 mm ve apikal seviyede 1,78 ve 1,34 mm olarak ölçüldü. Mann-Whitney U testi, endodontik tedavili ve sağlıklı üst birinci ve ikinci molarların kemik kalınlıkları arasında istatistiksel olarak anlamlı bir fark olmadığını göstermiştir. Sonuç: Bu çalışma, endodontik tedavi varlığının maksiller molarların kemik kalınlığı üzerinde bir etkisi olmadığı sonucuna varmıştır. No sponsor

The introduction of 3D diagnostic methods has brought about a global revolution in modern orthodontics. Among these, the introduction of digital data systems (digital models as STL files and cone-beam computed tomography scans in DICOM format) has had great clinical impact. The latest orthodontic application of these types of data is the possibility of matching them to obtain precise and faithful 3D reconstructions that contain information on both dental arches and the dentoskeletal structures. Acquiring important information such as bone thickness and morphology has made it possible to improve the validity, safety and reliability of palatal miniscrew insertion through the construction of digitally designed surgical guides (miniscrew-assisted palatal application, MAPA system) that enable controlled miniscrew insertion at the required angle and at the optimal depth, providing bicortical or tricortical anchorage in a safe and repeatable fashion.

Objective: Facial alveolar bone (FAB) thickness has crucial clinical importance due to its effect on periodontal surgery, immediate implant placement. The purpose of the present study is to investigate facial alveolar bone thickness of maxillary first and second molars by cone-beam computed tomography (CBCT). Material and method: Sixty-eight CBCT images belong to non-smoking healthy patients were retrospectively scanned and 84 three-rooted maxillary molars were selected. Endodontic treatment, post-core restoration, furcation and periapical lesion, root resorption, periodontal loss and previous orthodontic treatment were excluded from the study. FAB thicknesses of mesial and distal roots were measured at bone crest, 6 mm from bone crest and apical level of the root. Images were viewed on coronal, axial and sagittal plane in CBCT. The statistical analysis was performed. Results: FAB thicknesses of mesial and distal roots of first molar were 0,58 and 0,75 mm at bone crest and 0,39 and 0,96 mm at 6 mm from bone crest and 1,06 and 1,18 mm at apical, respectively. For second molar, 0,80 and 1,15 mm at bone crest and 1,52 and 1,48 mm at 6 mm from bone crest and 2,81 and 2,09 mm at apical, respectively. There is a statistically significant difference between the mesial root of the first and second molar at the bone crest, 6 mm from the bone crest, and apical of the root. For the distal root, there is a significant difference between the first and second molar at the bone crest and 6 mm from the bone crest. There is no significant difference at the apical of the root. Conclusion: The present study concluded that FAB thickness of the distal root of the fist molar is lower than the second molar. It is recommended the detailed examination of FAB thickness of the first molar when implant or periodontal surgery is needed. Amaç: Fasiyal alveoler kemiği kalınlığı, periodontal cerrahi ve çekim sonrası immediate implant yerleştirilmesi ve soketin boyutsal değişiklikleri üzerindeki etkisi nedeniyle klinik öneme sahiptir. Bu çalışmanın amacı; birinci ve ikınci maksiller molar dişlerdeki fasiyal alveoler kemik kalınlığının konik ışınlı bilgisayarlı tomografi (KIBT) kullanarak incelenmesidir. Yöntem: Sigara içmeyen sağlıklı hastaya ait altmış sekiz KIBT görüntüsü retrospektif olarak tarandı ve 84 üç köklü maksiller molar diş (42 birinci ve 42 ikinci molar) seçildi. Endodontik tedavili, post-core uygulanmış, furkasyon ve periapikal lezyonlu, kök rezorpsiyonlu, periodontal kaybı olan ve ortodontik tedavili dişler çalışma dışı bırakıldı. Mezial ve distal köklerin fasiyal alveolar kemik kalınlıkları kret tepesinden, kret tepesinin 6 mm apikalinden ve kökün apikal seviyesinden ölçüldü. Görüntüler KIBT'de x5 büyütmede koronal, aksiyel ve sagital düzlemde incelendi. İstatistiksel analiz yapıldı. Bulgular: Birinci moların mezial ve distal köklerinin kemik kalınlıkları kret tepesinde 0,58 ve 0,75 mm, kret tepesinden 6 mm apikalde 0,39 ve 0,96 mm ve apikalde 1,06 and 1,18 mm olarak ölçüldü. İkinci molar için kret tepesinde 0,80 ve 1,15 mm, kret tepesinden 6 mm apikalde 1,52 ve 1,48 mm ve apikal seviyede 2,81 ve 2,09 mm olarak ölçüldü. Student t-testi, birinci ve ikinci molar dişlerin mesial köklerinin kemik kalınlıkları arasında kret tepesinde, kret tepesinin 6 mm apikalinde ve kökün apikalinde istatistiksel olarak anlamlı bir fark olduğunu gösterdi. Distal kök için, birinci ve ikinci molarların bukkal kemik kalınlıkları arasında kret tepesinde, kret tepesinin 6 mm apikalinde istatistiksel olarak anlamlı bir fark vardır. Kökün apikal seviyesinde fark yoktur. Sonuç: Bu çalışma, birinci moların mezial kökünün alveoler kemik kalınlığı ikinci molardan daha düşük olduğunu göstermiştir. Aynı şekilde, birinci molarların distal kökün alveolar kemik kalınlığı, kret tepesi ve kret tepesinin 6 mm apikalinde ikinci molardan daha düşüktür. Birinci molarlara implant cerrahisi ve periodontal cerrahi gerekliliğinde bu bölgedeki kemik kalınlığının daha ayrıntılı incelenmesi önerilmektedir. No sponsor

Purposes. The thickness of the buccal bone and its covering gingiva is pivotal in determining the prognosis of implant therapy as well as fixed orthodontic appliances, especially nonextraction treatments. The purpose of this study was to evaluate the buccal bone thickness and covering soft tissue in the maxillary anterior segment. Methods. This study measured the hard tissue thickness at 2 and 5 mm more apical from the crest and at the root apical apex, as well as the distance from the CEJ to the alveolar crest, using 80 CBCT images divided into three age groups. In addition, the distance from free gingiva to alveolar crest and from free gingiva to CEJ was measured. The acquired data then was analyzed using an ANOVA, t-test, and Pearson correlation to investigate any associations or statistically significant differences between parameters. Results. The highest mean soft tissue thickness at the 5 mm level was for central incisors and the least for canine. The highest mean thickness of soft tissue at the crest level and its 2 mm apical level was related to central incisors and the lowest mean thickness at these levels was related to canine. Analysis of hard tissue variables showed the lower thickness of hard tissue at higher ages compared to the young patients group, but the thickness of the soft tissue increases with age. Conclusion. The highest mean thickness of the buccal hard tissue in the maxillary anterior segment was in lateral and central incisors. Also, the most prominent thickness of the labial soft tissue was in the central and lateral incisors at levels close to the crest.

BACKGROUND: To evaluate whether buccal bone thickness (BBT), implant diameter, and abutment/crown material influence the accuracy of cone beam computed tomography (CBCT) to determine the buccal bone level at titanium implants.METHODS: Two implant beds (i.e., narrow and standard diameter) were prepared in each of 36 porcine bone blocks. The implant beds were positioned at a variable distance from the buccal bone surface, thus resulting in 3 BBT groups (i.e., > 0.5-1.0; > 1.0-1.5; > 1.5-2.0 mm). In half of the blocks, a buccal bone dehiscence of random extent ("depth") was created and implants were mounted with different abutment/crown material (i.e., titanium abutments with a metal-ceramic crown and zirconia abutments with an all-ceramic zirconia crown). The distance from the implant shoulder to the buccal bone crest was measured on cross-sectional CBCT images and compared to the direct measurements at the bone blocks.RESULTS: While abutment/crown material and implant diameter had no effect on the detection accuracy of the buccal bone level at dental implants in CBCT scans, BBT had a significant effect. Specifically, when BBT was ≤ 1.0 mm, a dehiscence was often diagnosed although not present, i.e., the sensitivity was high (95.8%), but the specificity (12.5%) and the detection accuracy (54.2%) were low. Further, the average measurement error of the distance from the implant shoulder to the buccal bone crest was 1.6 mm.CONCLUSIONS: Based on the present laboratory study, BBT has a major impact on the correct diagnosis of the buccal bone level at dental titanium implants in CBCT images; in cases where the buccal bone is ≤ 1 mm thick, detection of the buccal bone level is largely inaccurate. This article is protected by copyright. All rights reserved.

Aim: The aim of the present study was to evaluate prevalence of fenestration and facial bone thickness in the lower anterior teeth using cone beam computed tomography (CBCT). Materials and Methods: Images of 78 patients who reffered to clinic were retrospectively reviewed. Endodontic treatment, periapical lesion, root resorption and orthodontic treatment were excluded from the study. Images were viewed on coronal, axial and sagittal plane in CBCT. For the study, 370 lower anterior teeth were selected. Facial bone widths were measured at 1 mm and 5 mm to the alveolar bone peak and apical. The prevalence of fenestration in lower anterior teeth was recorded. The statistical analyses were performed. Results: For this study, 125 central, 115 lateral and 130 canine were examined. The prevalence of fenestration rate in central, lateral and canine were 4.80 %, 4.34 % and 6.92 %, respectively. The buccal bone thicknesses at 1 mm in central, lateral and canine were 0.61 mm, 0.63 mm and 0.69 mm, respectively. For the level of 5 mm; these results were 0.62 mm, 0.66 mm and 0.64 mm, and for apical level; 2.96 mm, 2.93 mm and 3.02 mm. There was no statistical difference between bone thickness in all teeth. No statistical difference was found between age groups and sex. Bone thickness more than 2 mm was not found in all teeth groups at 1 and 5 mm level from bone peak. Conclusion: In this study, the buccal bone thickness of all teeth groups was less than 2 mm at the level of 1 and 5 mm from the bone crest. This region is risky in terms of resorption. The highest fenestration rate was in canine. The bone thickness and presence of fenestration of lower anterior teeth using CBCT should be evaluated before periodontal surgery, implant surgery, and orthodontic treatment. Amaç: Bukkal kemik kalınlığı; periodontal cerrahi, çekim sonrası implant yerleştirilmesi ve soketin boyutsal değişiklikleri üzerindeki etkisi nedeniyle klinik öneme sahiptir. Bu çalışmanın amacı, alt anterior dişlerin bukkal alveoler kemik kalınlığı ve fenestrasyon prevalansının konik ışınlı bilgisayarlı tomografi (KIBT) ile araştırılmasıdır. Gereçler ve Yöntemler: Üniversite kliniğine başvuran hastaların KIBT görüntüleri retrospektif olarak değerlendirildi. Endodontik tedavi görmüş, periapikal lezyonlu, kök rezorbsiyonlu, periodontal kayıplı ve ortodontik tedavi görmüş dişler çalışma dışı bırakıldı. Toplam 78 hastada 370 adet alt anterior diş çalışma için seçildi. Bukkal kemik kalınlığı kret tepesinden 1 mm, 5 mm mesafeden ve apikalden iki gözlemci tarafından ölçüldü. Fenestrasyon varlığı üç boyutlu rekonstrüksiyon görüntüleri kullanılarak tespit edildi. İstatistiksel analiz yapıldı. Bulgular: Bu çalışma için, 125 santral, 115 lateral ve 130 kanin, toplamda 370 anterior diş incelendi. Alt anterior dişlerde fenestrasyon oranı santral, lateral ve kaninde sırasıyla; % 4.80, % 4.34 ve % 6.92 olarak bulundu. Bukkal kemik kalınlığı ortalamaları 1 mm seviyesinde; santral, lateral ve kaninde sırasıyla; 0.61 mm, 0.63 mm ve 0.69 mm olarak tespit edildi. Bu sonuçlar 5 mm mesafede; 0.62 mm, 0.66 mm ve 0.64 mm, apikalde; 2.96 mm, 2.93 mm ve 3.02 mm bulundu. Kemik kalınlığı açısından dişler arasında istatistiksel olarak anlamlı bir fark bulunmadı. Yaş grupları ve cinsiyet arasında da tüm kemik seviyeleri için anlamlı bir fark bulunmadı. Tüm dişlerde, 1 mm ve 5 mm seviyesinde, 2 mm’den kalın bukkal kemik tespit edilmedi. Sonuç: Alt anterior bölgede bukkal kemik kalınlığı kemik kretinden 1 mm ve 5 mm mesafede, 2 mm’den ince bulundu. Bu bölge cerrahi işlemler sonrasında kemik rezorbsiyonu açısından risklidir. Bu çalışmada en yüksek fenestrasyon oranı kaninde görüldü. Periodontal cerrahi, implant cerrahisi ve ortodontik tedavi öncesi bu dişler fenestrasyon varlığı açısından değerlendirilmelidir. Alt anterior bölgeye uygulanacak periodontal cerrahi operasyonlarda şüpheli bölgenin anatomik yapısının doğru bir şekilde belirlenmesi için KIBT’nin kullanımı yararlıdır. No sponsor

Background: Vestibular bone thickness changes and dento-alveolar buccal tipping of second primary molars and of first molars after maxillary expansion performed with a slow maxillary expansion protocol was investigated. Methods: Twenty patients (mean age 7.3 &plusmn, 0.9 years old, 9 male and 11 female) were treated according to the Leaf Expander protocol. Buccal alveolar bone thickness (BT), buccal alveolar bone height (BH), inter-dental angle (TIP), and inter-molar width (IW) regarding first molars and second primary molars were calculated before and after expansion on cone beam computed tomography (CBCT) images. Descriptive statistics and paired t-tests were used to assess changes between the pre-treatment and post-treatment measurements. Results: Bone thickness vestibular to second primary molars and intermolar width of both teeth were the only variables that showed statistically significant changes. Conclusions: It appears that buccal bone thickness vestibular to first molars was not significantly reduced after maxillary expansion with the Leaf Expander. The clinical use of a slow maxillary expander with Ni&ndash, Ti springs appears efficient and safe in in the correction of maxillary hypoplasia during mixed dentition.

Background The use of guided bone regeneration (GBR) for vertical and horizontal bone gain is a predictable approach to correct the bone defects before implant installation; however, the use of different protocols is associated with different clinical results. It is suggested that platelet-rich fibrin (PRF) could improve the outcomes of regenerative procedures. Thus, this study aimed to describe the bone gain associated with GBR procedures combining membranes, bone grafts, and PRF for vertical and horizontal bone augmentation. Materials and methods Eighteen patients who needed vertical or horizontal bone regeneration before installing dental implants were included in the study. The horizontal bone defects were treated with a GBR protocol that includes the use of a mixture of particulate autogenous and xenogenous grafts in the proportion of 1:1, injectable form of PRF (i-PRF) to agglutinate the graft, an absorbable collagen membrane covering the regenerated region, and leukocyte PRF (L-PRF) membrane covering the GBR membrane. The vertical bone defects were treated with the same grafted mixture protected by a titanium-reinforced non-resorbable high-density polytetrafluoroethylene (d-PTFE-Ti) membrane and covered by L-PRF. The bone gain was measured using a cone-beam computed tomography at baseline and after a period of 7.5 (± 1.0) months. Results All patients underwent surgery to install implants after this regenerative protocol. The GBR produces an increase in bone thickness (p < 0.001) and height (p < 0.005) after treatment, with a bone gain of 5.9 ± 2.4 for horizontal defects and 5.6 ± 2.6 for vertical defects. In horizontal defects, the gain was higher in the maxilla than in mandible (p = 0.014) and in anterior than the posterior region (p = 0.033). No differences related to GBR location were observed in vertical defects (p > 0.05). Conclusion GBR associated with a mixture of particulate autogenous and xenogenous grafts and i-PRF is effective for vertical and horizontal bone augmentation in maxillary and mandibular regions, permitting sufficient bone gain to future implant placement. Trial registration REBEC, RBR-3CSG3J. Date of registration—19 July 2019, retrospectively registered. http://www.ensaiosclinicos.gov.br/rg/RBR-3csg3j/

Today 3D modeling with AI involvement is a promising direction in all branches of science, in particular in medicine and especially in otolaryngology. The study involved 100 subjects without any abnormalities of the ENT organs. The main anatomical structures of the ostiomeatal complex, the sizes of which were determined, were the uncinated process, the middle nasal concha and the natural anastomosis between the nasal cavity and the anterior group of the paranasal sinuses. On the basis of the study, it can be assumed that the structure of the ostiomeatal complex components during 3D modeling is as close as possible when measured in vivo by means of endoscopic surgical treatment.

A 70-year-old edentulous male presented with bilateral mandible and left midface fractures following an assault. Imaging confirmed fractures and showed mandible thickness greater than 20 millimeters. The patient was treated by open reduction internal fixation with miniplates via an intra-oral approach and recovered without deficit. While miniplate fixation and an intra-oral approach is typically reserved for the dentulous patient, this case illustrates that in select edentulous patients with sufficient bone thickness and amenable midface fractures this technique may be successfully utilized.

The purpose of this study was to determine the palatal bone and soft tissue thicknesses using a miniscrew-supported maxillary skeletal expander (MSE) in Class III malocclusion. The thicknesses of the palatal bone and soft tissue were measured in cone-beam computed tomography images obtained from 58 patients. All 20 points were crossing points between five levels, which were defined at 3 mm intervals relative to the line connecting the central fossae of the first molar (Level 0), and 2 mm and 4 mm lateral to the anteroposterior reference line (AP line). The palatal bone was significantly thicker in males than females in the anterior palate up to Level 0, while there was no significant sex-related difference in the posterior palate. There was a tendency for the thickness to decrease in the posterior direction, except in females at 2 mm lateral to the AP line. The palatal soft tissue was significantly thicker in males than females in all positions. At 2 mm lateral to the AP line, the palatal soft tissue thickness decreased in the posterior direction. A 4 mm lateral to the AP line, it initially decreased in the posterior direction, and then increasing again at Level − 6 (6 mm posterior of Level 0). As the lateral distance from the AP line increased, the palatal bone thickness decreased while the palatal soft tissue thickness increased. These findings provide quantitative data on the palatal bone and soft tissue thicknesses for the miniscrew-supported MSE in the posterior palate.

Purpose Mandibular reconstitution with bioabsorbable scaffolds seems feasible with the application of 3-dimensional printing combined with bioactive proteins. As yet, previous studies have been limited in number of animals and have avoided a contaminated defect. We present a caprine model of mandibular defect bone regeneration with a 3-dimensionally printed bioabsorbable scaffold contaminated with oral secretions and explore the impact of bone morphogenic protein in mandibular bone reconstitution. Methods A 3-cm, contaminated mandibular defect was generated in 18 goats and stabilized with 2 mandibular reconstruction plates. An uncoated scaffold was placed in 6 goats, and in the final 6 goats, the scaffold was coated with bone morphogenic protein-2. In 6 goats, the defect was left empty. After 12 weeks, the operative site, scaffold, and adjacent mandible were plasticized, sectioned, and evaluated histologically to assess for bone regeneration. Results The specimens revealed only focal (average of 5.8% of the scaffold pores) and early bone formation in the scaffold-only group. In the scaffold + bone morphogenic protein-2 group, there was more (average of 51.4% of the pores) bone formation. In the periosteum-only group, the ratio of the bone thickness of the defect to that of the normal bone ranged from 0.16 to 0.78. No major infections occurred. Conclusions This caprine model serves as an excellent method to assess reconstructive options for contaminated mandibular deficits. Bone regeneration was documented in a 3-cm contaminated caprine mandibular defect reconstructed with a 3-dimensionally printed synthetic scaffold with or without the addition of bone morphogenic protein-2. Bone morphogenic protein-2 significantly augments bone generation in the synthetic scaffold. Residual mandibular periosteum generated bone. Future studies will focus on optimizing vascularization.

The association between tooth movement and remodelling of surrounding bone is controversial. To analyse the effect of tooth movement on alveolar bone changes in maxillary and mandibular anterior teeth by cone-beam computed tomography (CBCT). The Embase, Cochrane Library and Medline databases were searched without any language restrictions. Longitudinal studies using CBCT to observe alveolar bone changes of maxillary and mandibular anterior teeth during orthodontic treatment were included. Two independent reviewers performed the study selection, data extraction and methodological quality assessment. A total of 26 studies were included in this review, 14 of which were eligible for quantitative synthesis. In extraction cases, meta-analysis showed vertical bone loss on the labial (0.36 mm) and lingual (0.94 mm) sides of maxillary incisors, and lingual bone thickness decreased significantly at the cervical level (0.57 mm). In non-extraction cases, vertical alveolar bone loss was significant on the labial side (0.97 mm) and lingual side (0.86 mm) of mandibular incisors. Subgroup analysis for skeletal class III patients indicated that vertical alveolar bone loss was 1.16 mm on the labial side and 0.83 mm on the lingual side of mandibular incisors. The absence of high-quality studies and the high heterogeneity of the included studies were limitations of this systematic review and meta-analysis. Based on limited evidence, alveolar bone height and thickness, especially at the cervical level, decreased during both labial and lingual movement of anterior teeth.

Despite the importance of image assessment in the biomedical field (radiation diagnosis, otolaryngology, dentistry, pathology, etc.) there is no clearly defined unified image processing algorithm to date, the result of examination and interpretation of these images often depends on the physician's qualifications and experience. The purpose of our study was implementation of the computer vision system for evaluation of CT images for obtaining impersonal real data. Thus, in the course of the study, a number of medical goals were solved, which included the need to measure bone thickness on radiograms, tomograms, SCTs and other images. This is especially relevant for measuring the minimum thickness, as a thin bone can be easily damaged by a medical instrument during surgery (for example, damage to the upper wall of the maxillary sinus with damage to the orbit). The suggested method could be used for automated measurement of bone thickness of the walls of the paranasal sinuses. The obtained results can be implemented in the work of doctors in a number of specialties (therapists, radiologists, otolaryngologists, dentists, ophthalmologists, neurosurgeons) for study many biomedical images.

Summary Background Currently, sequential morphological changes of vascularized scapular bone for mandibular reconstruction have remained unreported. Methods We retrospectively analyzed 18 patients with defects on the lateral segment of the mandible who underwent postoperative computed tomography (CT) scanning at 1, 6, 12, and 24 months postoperatively. Using the cross-sectional coronal CT images during each assessment, we measured the height and thickness of the grafted scapular bone at points 10 and 30 mm away from the mesial segment and evaluated their differences over time. Then, the relationship between the morphological changes of the grafted scapular bone and the distance from the mesial bone segment, the number of occlusal supports on the contralateral side of the mandible, and the correlation of sex and age were evaluated. Results The height of the grafted scapular bone decreased by approximately 11% and its thickness increased by 14% within 24 months postoperatively. The bone thickness increase was greater at point 30 mm from the mesial bone segment. Patients with two occlusal contacts (premolar and molar) on the contralateral side had a significantly higher rate of bone thickness increase. Furthermore, the graft morphology was not associated with age or sex. Conclusion A vascularized scapular bone thickens over time, which depends on the distance from the mesial bone segment and the occlusal contact regions on the contralateral side of the mandible.

Aim To systematically review buccal bone thickness (BBT) in the anterior maxilla in different teeth, age groups and genders. Materials and methods PubMed, EMBASE and Cochrane databases were searched up to April 2020. Clinical and radiographic studies reporting on BBT of maxillary anterior teeth, with at least 10 patients, were included. A meta-analysis was performed using random effect models to report differences of BBT. Results 50 studies were included. Using bone crest (BC) as a reference point, no significant differences were found in BBT between different tooth types, except for 0.16 mm (95%-CI: 0.02-0.30) increased mid-root thickness of premolars compared to canines. Using the CEJ as a reference point, canines presented with a significantly increased thickness of 0.32 mm (95%-CI: 0.11-0.54) coronally compared to laterals. When BC was used as reference, males demonstrated a significantly increased thickness of 0.21 mm (95%-CI: 0.15-0.27) apically, while middle-aged adults showed a 0.06 mm (95%-CI: -0.12, -0.01) statistically significant increase in the coronal level compared to older adults. Conclusions Few maxillary anterior teeth have BBT greater than 1 mm. Buccal bone tends to get thicker from a coronal to apical position along the root surface and from an anterior to posterior position in the arch.

Two current approaches to the ergometric evaluation of the impact strength that lead to skull fracture are described. Within each of them, the features of particular techniques, typical expert errors, ways and means of preventing them are analyzed. Quantitative data on the contribution of various initial parameters (fracture type, age, bone thickness, skull radius of curvature, body weight, height, etc.) to the result of computational diagnostics are presented.Описаны два сложившихся на сегодняшний день в судебной медицине подхода к эргометрической оценке силы удара, повлекшего перелом черепа. В рамках каждого из них анализируются особенности частных методик, типичные экспертные ошибки, пути и способы их предотвращения. Представлены количественные данные о вкладе различных исходных параметров (вид перелома, возраст, толщина кости, радиус кривизны черепа, масса тела, рост и др.) в результате вычислительной диагностики.

Deproteinized bovine bone mineral (DBBM) is brittle and can break into fragments. Here, we examined whether DBBM fragments have an impact on mice calvarial bone during bone augmentation. DBBM was either randomly crushed (DBBM fragments) or left undisturbed (DBBM granules). Then, DBBM fragments or original DBBM granules were placed onto calvarial bone in 20 BALB/c mice. Following random allocation, ten mice received DBBM fragments and ten mice received original DBBM granules. After fourteen days of healing, micro computed tomography (micro-CT) and histological analysis of the augmented sites were performed. The primary outcome was the porosity of the calvarial bone. The micro-CT analysis revealed that DBBM fragments failed to significantly change the porosity of the calvarial bone as compared with original DBBM granules, despite the slightly higher bone resorption in the DBBM fragment group, 10.3% (CI 6.3&ndash, 11.6) versus 6.1% (CI 4.1&ndash, 7.8, p = 0.355), respectively. The cortical bone volume was not altered by DBBM fragments as compared with original DBBM granules, i.e., 79.0% (CI 78.9&ndash, 81.2) versus 81.5% (CI 80.1&ndash, 83.3, p = 0.357), respectively. The DBBM fragment group revealed similar bone thickness values as compared with the DBBM granules group, i.e., 0.26 mm (CI 0.23&ndash, 0.29) versus 0.25 mm (CI 0.22&ndash, 0.27, p = 0.641), respectively. The histological evaluation supported the micro-CT observations, displaying minor signs of porosity and resorption. The particle-size distribution analysis confirmed a shift towards smaller particle sizes in the DBBM fragment group. These findings suggest that DBBM fragments behave similarly to original DBBM granules in terms of bone morphological changes at augmented sites.

Objective: To demonstrate the feasibility of robotic cochlear implant surgery in subject specific pediatric phantoms. Study design: Pilot study. Materials and Methods: Computed tomographic preoperative encrypted data of ten pediatric subjects (total of 20 sides) between eight months and forty-eight months old, who underwent cochlear implant surgery were studied. Four datasets (n=8 sides) were selected for investigation of the complete robotic procedure including middle and inner ear access and electrode insertion. Results: The planning of the safe trajectory for the robotic approach was possible in 17 of the cases. In 3 sides, planning the trajectory was not possible due to the small size of the facial recess. Bone thickness study demonstrated average sufficient bone thickness at the site of screw implantation in general. The complete robotic procure including the drilling and insertion was successfully carried out on all the created phantoms. Conclusion: With this work we have demonstrated the feasibility of planning and performing a robotic middle and inner ear access and cochlear implantation in phantom models of pediatric subjects. To develop and validate the proposed procedure for use in children, next stage optimization of the current surgical workflow and adaptation of the surgical material to pediatric population is necessary.

The use of mandibular overdentures (MO) for the rehabilitation of totally edentulous individuals with limited bone availability is widespread and has proven clinical success. Narrow diameter implants (NDI) are available on the market as MO retainers to solve problems related to limited bone availability and bone thickness, providing a low-cost, minimally invasive treatment option. This technique evolved over the years, and changes frequently involved the number of implants used as MO retainers, as the adoption of a smaller number of implants can generate biomechanical disadvantages, contributing to the increased stress in peri-implant tissues, which may accelerate marginal bone loss (MBL), in addition to reducing masticatory capacity and satisfaction with rehabilitation. Some studies pointed out that the use of 3 or more implants as MO retainers improves the biomechanics. Thus, the objective of this study was to report 3 different clinical cases where 3 or more NDI were adopted to retain mandibular overdentures in association with diverse loading protocols: (i) 3 implants adopting conventional loading, (ii) 4 implants using progressive loading, and (iii) 4 implants with hybrid loading. The case with 4 implants and progressive loading showed a slight worsening of masticatory function at 1 year, in addition to a more pronounced MBL compared to other cases, but with improvements in satisfaction and oral health-related quality of life. Thus, NDI can be used as MO retainers with predictability and clinical success, using different numbers of implants and loading protocols.

Background Analysis of the anatomy of the region during preoperative planning is very important in order to minimize the risks of undesired movements in the supporting teeth or even damage to important structures such as the maxillary sinus. To the best of our knowledge, no study evaluated the relationship of these skeletal patterns with the anatomy of the infrazygomatic crest. The aim of this study was to evaluate the tomographic measurements of the infrazygomatic crest for placement of temporary anchorage devices in individuals with different vertical and sagittal skeletal patterns. Material and methods The measurements were analyzed in three regions in the crest of 67 patients above the maxillary first molar: A slice in the long axis of the mesiobuccal root, a slice passing through the center of the furcation area of the tooth, and another slice in the long axis of the distobuccal root. In each of these slices five measurements of the thickness of the infrazygomatic crest were performed, with a difference of 1 mm between them. The sagittal skeletal pattern was determined by the ANB angle and the vertical skeletal pattern by the SN.GoGn angle. Results The bone thickness of the crest tended to decrease gradually in the apical direction. There was no difference between different vertical and sagittal skeletal patterns. Conclusions The individual parameters did not have significant influence in the thickness of the infrazygomatic crest. Key words:Tomography, X-Ray Computed, orthodontics, mini-implant, infrazygomatic crest, maxilla.

Introduction Orthodontic space closure after premolar extraction commonly results in the formation of a gingival cleft, which may contribute to orthodontic relapse and poor periodontal health. The purpose of this study was to examine clinical parameters that may predispose patients to gingival clefts. Methods Twenty-nine patients planned for treatment with premolar extractions (n = 87) and orthodontic space closure were evaluated in this prospective study. The clinical measures included width of keratinized buccal gingiva, thickness of buccal gingiva, thickness of buccal bone, time of space closure, and the occurrence (presence or absence) and severity (volume) of cleft formation. The association of the clinical measures with gingival cleft formation and severity was assessed separately for patients according to age group: young adolescent (≤13 years of age), adolescent (14-18 years of age), and adult (≥19 years of age). Results The overall incidence of gingival cleft formation was 73.2%, with a trend toward greater cleft formation in the young adolescents (79.4%) than in the adolescent and adult groups (69.2% and 68.2%, respectively). The mean severity of clefts exhibited a significant positive association with age group—young adolescent (26.6 mm2), adolescent (27.9 mm2), and adult (41.5 mm2). Buccal bone thickness was significantly correlated with gingival phenotype in the adolescent and adult groups (r = 0.42 and r = 0.52, respectively; both, P Conclusions The formation of gingival clefts is common after premolar extraction and space closure. Adults with a thinner gingival phenotype were more likely to develop gingival clefts of greater severity. The rate of space closure was significantly and inversely correlated with cleft formation in adults, reflecting a greater likelihood of cleft formation with slower space closure. Although various clinical parameters show a correlation to both severity and incidence of clefts, all patients undergoing postextraction space closure appear to be at risk and should be monitored.

In implantology, an increase in the bone thickness of the alveolar ridge is often associated with the use of autogenous bone, which is considered to be the gold standard. The aim of the present study was to report the clinical case of a patient with abnormal bone thickness in the alveolar ridge, causing severe esthetical damage, and the use of xenogeneic block bone grafts. A female, 43-year old patient exhibited a considerable bone defect in the region of teeth 11 (absent), although there was sufficient native bone available for the implantation. The patients treatment involved positioning the implant and performing a block bone graft using bone of bovine origin. The post-operative period passed without complications. The post-operative clinical examination confirmed the correction of the pre-existing esthetic defect and the health of the soft tissues involved. The tomographic examination 180 days post-surgery also confirmed an excellent increase in thickness. The bovine block bone graft used in the present case was shown to be viable in terms of correcting esthetic defects when there is sufficient native bone available for the implantation.

To noninvasively determine the relationship between the thickness of the buccal bone and attached gingiva of the maxillary premolars.128 maxillary premolars in 32 patients were assessed for measurement of buccal bone thickness and corresponding attached gingival thickness at 3 mm apical to cemento-enamel junction. Buccal bone thickness was measured on cone-beam computed tomography scans and attached gingival thickness by ultrasound unit. Pearson's correlation coefficient was calculated to assess the correlation between buccal bone and attached gingival thickness at each tooth type.The mean buccal bone thickness at the maxillary premolars was 1.07 mm. The 1st premolars had a buccal bone thickness 1 mm at 68% of all sites, and the 2nd premolars had a buccal bone thickness of 1.0-2.0 mm at 32% of all sites. The 1st premolars had a gingival thickness 1.2 mm at 55% of all sites, and the 2nd premolars had a gingival thickness of 1.1-1.3 mm at 45% of all sites. The correlation between buccal bone and attached gingival thickness was moderately positive (r = 0.406; P .001).The relationship between buccal bone thickness and gingival thickness is independent of each other in the maxillary right first premolar, whereas a moderate correlation with a dependent relation exists in the maxillary right second premolar, maxillary left first premolar, and maxillary left second premolar.Soft tissue and hard tissue associated with volumetric changes in maxillary premolar region can be unfavorable for both aesthetic and implant placement. In fact this study highlighted the relationship between the thickness of attached gingiva and corresponding buccal bone in maxillary premolar region so to enable for proper planning of implant therapy following extraction.

To prospectively evaluate morphological changes in the horizontal and vertical dimensions of peri-implant tissue at 1-year post-prosthesis implantation.Thirty-four patients who had received implants with conical connections in the aesthetic region were included in the follow-up study. Patients had received either traditional delayed implant placement or tissue augmentation with or without immediate implant placement. The horizontal and vertical dimensions of the buccal alveolar bone of the implant and its surrounding soft tissues were then evaluated using cone beam computed tomography.Implants placed alongside tissue augmentation, with or without immediate placement, were as successful as those placed into sites with traditional delayed implant placement. Statistically significant negative correlations were observed between initial horizontal bone thickness and changes in vertical bone height (r=0.585, p0.05) and vertical soft tissue height (r=0.378, p0.05), and between initial horizontal soft tissue thickness and the change in vertical soft tissue height (r=0.627, p0.05).Regardless of the bone and soft tissue augmentation approach, implants with conical connections may effectively preserve peri-implant tissues. However, the thickness of the peri-implant soft tissue is essential, because a change in soft tissue margin level tends to be affected by the thickness of the peri-implant soft tissue rather than the bone width.

BACKGROUND The traditional method of evaluating bone remodeling in chronic rhinosinusitis is to measure bone thickness. The objective of this study was to determine the feasibility of measuring the computed tomography (CT) value in Hounsfield units (HU) as an method and explore whether it is superior to measuring bone thickness. METHODS The study was a prospective animal trial. Twenty normal rabbits were included in the control group, and 60 rabbit models were inoculated with Staphylococcus aureus to induce rhinosinusitis. The rabbit models were divided into 3 groups according to the time of infection. All animals were euthanized after the CT exam. The samples were scored based on mucus and bone changes. The rabbits were divided into negative and positive groups according to whether bone remodeling was observed. We obtained diagnostic threshold values by measuring the bone thickness and HU of each rabbit's maxillary sinus and compared the values obtained using the 2 methods by calculating the area under the receiver operating characteristic curve (AUC). RESULTS The AUC for the measured bone thickness was 0.838, the diagnostic threshold was 1.165 mm. The AUC for the measured HU value was 0.937, the diagnostic threshold was 904.5. The correlation coefficients were r1 = 0.645 for the measured bone thickness and r2 = 0.797 for the HU measurement (r2 > r1 ; p < 0.01). CONCLUSION Evaluating bone remodeling is feasible by measuring either the bone wall thickness or the CT value. However, using CT to evaluate the sinus bones in rabbits with rhinosinusitis appears to be a more valuable option.

OBJECTIVES The diploic channels are bony passages of veins, running within frontal, parietal, and occipital bones. In this study, we investigate ontogenetic changes of these channels in a sample of nonadult and adult modern humans. MATERIALS AND METHODS Using computed tomography scans of dried crania, we provide quantitative comparisons of lumen size, branch length, volume, and vascular asymmetries, and correlations with age, cranial size, and bone thickness. RESULTS The vascular system displays progressive but nonlinear changes throughout ontogeny, becoming even more complex with adulthood. Vascular variables are significantly different in frontal, parietal, and occipital bones for most of the postnatal ontogeny. Diploic channels of the left and right sides are developed similarly. Vascular variables display a nonlinear association with age and cranial size in modern humans. Cranial bone thickness is shown to be a major determinant of lumen size, branch length, and volume. CONCLUSIONS A previous radiographic survey suggested that diploic channels are more developed in adult modern humans than in nonadults. Recent advances in digital anatomy have been used in this study to investigate this craniovascular structure. The complexity of the channels increases during development, with a noticeable boost in adults. Taking into account the potential metabolic differences and constraints associated with modern human brain size and shape, the vascular differences found might be related to endocranial thermoregulation.

WOS: 000448802300006, PubMed ID: 30102085, Objectives: To evaluate and compare the dental and skeletal changes with conventional and miniscrew-supported maxillary expansion appliances in adolescents. Materials and Methods: Forty patients were divided into two groups, with one group receiving a tooth-borne expander and the other group receiving an expander supported by four miniscrews (bone-borne). Multiplanar coronal and axial slices obtained from cone-beam computed tomography images were used to measure the changes in transverse skeletal widths, buccal bone thickness, tooth inclination, and root length. Paired t-tests and independent-sample t-tests were used to compare the two expansion methods. Results: Bone-borne expansion increased the maxillary suture opening more than 2.5 times than tooth-borne expansion both anteriorly and posteriorly. Between the maxillary first premolars, sutural expansion accounted for 28% and 70% of the total transverse width increase in the tooth-borne and bone-borne expander groups, respectively. Similarly, 26% and 68% of the total expansion was of skeletal nature in the tooth-borne and bone-borne expander groups between the maxillary first molars. The pattern of expansion was variable, with most of the patients in both groups demonstrating a triangular-shaped sutural opening that was wider anteriorly. Subjects in the conventional group experienced significantly more buccal bone reduction and greater buccal inclination of the teeth. No significant differences were observed for root length measurements between the two groups. Conclusion: Use of bone-borne expansion in the adolescent population increased the extent of skeletal changes in the range of 1.5 to 2.8 times that of tooth-borne expansion and did not result in any dental side effects.

Purpose The aim of this study was to evaluate volumetric stability of autologous and xenogeneic block grafts and primary stability of implants in maxillary grafted areas. Materials and methods Each patient received one autologous block and xenogeneic block, both covered with a membrane. Bone thickness measurements clinically and tomographically were made before, immediately, and 6 months postoperatively. After 6 months, identical implants were placed in each grafted area, and primary stability was measured. Results Eight patients with anterior horizontal bone defects were selected. Clinical outcomes at 6 months postgrafting in the autologous block revealed a mean thickness of 7.4 ± 1.6 mm, with an initial mean measurement of 3.4 ± 1.7 mm and 2.6% resorption, whereas the mean in the xenogeneic block was 8.9 ± 1.5 mm, 3.3 ± 1.6 mm, and 7.3%, respectively. Tomographic evaluation of the thickness at 6 months postgrafting in the autologous block was a mean 7.8 ± 1.8 mm, with an initial mean of 3.7 ± 1.6 mm and resorption of 0%, while the mean in the xenogeneic block was 9.3 ± 1.6 mm, 3.6 ± 1.4 mm, and 2.1%, respectively. No significant difference in bone thickness was observed immediately or 6 months after the procedure. The mean implant placement torque was 32 ± 22 Ncm in the autologous block and 18 ± 9 Ncm in the xenogeneic block (P = .004). Conclusion Xenogeneic block was shown to be a suitable alternative to reconstruct horizontal defects in the alveolar ridge that had undergone extensive resorption, though lower insertion torques were obtained during implant placement.

Objectives: The aim of the present study was to determine the correlation between the thickness of both cortical bone thickness, total bone thickness and the primary stability of mini-implants. Methods: Twenty-six mini-screws (Absoanchor) were inserted into the buccal alveolar bone between the roots of the second premolar and first molar on the right and left side of the patient. The mobility of the mini-screws was clinically assessed using the periotest device and the buccal cortical bone thickness of the maxilla was measured on the right and left side in the inter-radicular area between the second premolar and first molar at the site of the miniscrew insertion. The patient’s head was oriented in all 3 spatial planes by adjusting the Frankfort plane horizontal and the orbital plane parallel to the floor. Results: There was a statistical significant differences between mean measurements of the cortical bone thickness penetrated by the mini-screw and the negative stability scores. (P=0.03) Conclusions: There was a weak correlation between the primary stability of the mini-screw and the cortical bone thickness. However, a minimum thickness of 1.0 mm cortical bone thickness is necessary for adequate stability.

Introduction Microimplant-assisted rapid palatal expansion (MARPE) has recently been offered to adult patients for correcting maxillary transverse deficiency. However, there is limited information in the literature on the success of this appliance and its skeletal and dental effects on skeletally matured patients. The purpose of this study was to investigate the immediate skeletal, dentoalveolar, and periodontal response to MARPE appliance using cone-beam computed tomography in a skeletally matured patient as assessed by the cervical vertebral maturation method. Materials and Methods Eight consecutively treated patients (2 females, 6 males; mean age of 21.9 ± 1.5 years) treated with a maxillary skeletal expander were included in the study. Measurements were taken before and after expansion to determine the amount of midpalatal suture opening, upper facial bony expansion, alveolar bone bending, dental tipping, and buccal bone thickness (BBT). Data were analyzed using a one-way ANOVA and matched-pair t-test (α = 0.05). Results Midpalatal suture separation was found in 100% of the patients with no dislodged microimplants. Total maxillary expansion was attributed to 41% skeletal, 12% alveolar bone bending, and 48% dental tipping. Pattern of midpalatal suture opening was found to be parallel in both the coronal and axial planes. On average, the absolute dental tipping ranged from 4.17° to 4.96° and the BBT was reduced by an average of 39% measured at the premolars and molars. Conclusions The MARPE appliance can be a clinically acceptable, nonsurgical treatment option for correcting mild to moderate maxillary transverse discrepancies for skeletally matured adult patients with a healthy periodontium.

The aim of this study was to evaluate buccal-lingual bone remodeling after fresh socket implant placement and immediate loading at 3 years of follow-up by cone beam computed tomography (CBCT). A total of 96 implants were placed in fresh sockets in anterior maxillary regions and immediately loaded. The sockets were divided into two groups related to buccal bone thickness: group A, with a buccal bone thickness > 1 mm, and group B, with a thickness ≤ 1 mm. The CBCT scans were performed before tooth extractions and 3 years after implant placement, and measurements were assessed. At 3 years, all fresh sockets in both groups presented considerable buccal-palatal crestal reduction. In both groups, statistically significant (P < .05) bone loss was found between time points. There was no statistically significant difference in bone reduction between groups at 3 years of follow-up. Nevertheless, sockets with vertical axis presented more bone volume reduction than those with axis parallel to buccal bone after implant placement.

BACKGROUND Reduction malarplasty, popular among Asians, is currently performed preferably via the intraoral approach. However, to prevent complications such as malunion and cheek drooping, a rigid fixation is essential to compensate for the action of the masseter. Accordingly, the authors aimed to perform an experimental study on the optimal fixation location during intraoral reduction malarplasty using an L-shaped osteotomy. METHODS Fixation points that are not difficult to access during an L-shaped osteotomy were selected as 1 point in the freed zygomaticomaxillary complex and 3 points in the medial part of the malar complex (low, middle, and high levels).After setting the fixation points in the medial malar complex and lateral segment of skull replicates, resistance to traction was measured at each level, and maxillary bone thickness was also measured at each level at the fixation points of the medial malar complex in a cadaveric head. RESULTS In the medial malar complex, resistance to traction increased at higher levels, while the maxillary bone was much thicker at the high level than at the low-middle level. CONCLUSION This study demonstrated that it is better to locate the fixation point at a higher level in the medial part of the malar complex, closer to the lateral orbital rim.

Objective: To compare the bone morphology after secondary alveolar bone graft surgery (SABG) performed before and after permanent canine eruption. Design: Cross-sectional study. Setting: Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo, Bauru, SP, Brazil. Patients: 25 cone-beam computed tomography (CBCT) scans of complete unilateral cleft lip and palate (CLP) individuals who underwent SABG before or after eruption of the permanent canine taken 2 and 6 months (T1 and T2) after SAGB, resulting in 50 CBCT scans. Two groups were assessed, Ideal Group (IG; n = 10) and Late Group (LG; n = 15), according to the time of the SABG. Interventions: SABG buccal-palatal thicknesses were measured in 3 different root levels: cement-enamel junction (cervical slice), middle point of the root (intermediate slice), and apex of the central incisor (apical slice). Thickness measurements were assessed in the mesial, distal, and intermediate aspects of the alveolar bone graft. Clinical long-term follow-up was also done. Results: The IG showed significantly greater bone thickness, especially in the intermediate and apical slices, when compared to LG, in T1 and T2. Bone thickness was maintained over time. Clinically, all the IG individuals completed orthodontics, and no major complications were observed. In contrast, 27% of the LG individuals had failures, and rehabilitation was achieved through prosthesis. Conclusion: Ideal SABG presents with better results compared with late ABG. When it is not possible to perform SABG at the ideal time, acceptable outcomes still can be expected for late bone grafting.

Objective The aim of this study was to test the bone thickness and potential screw length for osteosynthesis of condylar base fractures (according to the Loukota classification) with an experimental titanium plate, placed in an ideal position against 2 types of conventional plates. Study Design After exclusion of completely edentulous mandibles, 28 dentate macerated mandibles available at the time of the study were included. Linear regression models 1 and 2 compared the sums of the 2 cranial bone thicknesses and the 3 caudal thicknesses among the 3 different plate designs, and linear models 3 and 4 tested the bone thickness in the 2 most cranial screw axes. Results Linear models 1 and 2 revealed significantly higher potential screw lengths for the experimental oblique plate. Equally, linear models 3 and 4 indicated significantly higher bone thickness for the novel oblique plate. Conclusion The novel proposed oblique plate allows for favorable plate positioning in a biomechanically ideal location with sufficient amounts of local bone for stable plate fixation. When plates with 15-degree angulated screw holes are used, stable bicortical plate fixation can be achieved.

OBJECTIVE To compare temporal bone thickness along a three-dimensional arc of potential osseointegrated implant sites for bone-anchored hearing aids in children with and without aural atresia using computed tomographic imaging (CT). STUDY DESIGN Retrospective case review. SETTING Tertiary children's hospital. PATIENTS Children with or without aural atresia aged less than 11 years who had a temporal bone CT. INTERVENTION (S) Calvarial bone volume on CT was rendered in three-dimensional and thickness was reconstructed and measured at up to 12 defined sites along an arc of recommended implant sites. MAIN OUTCOME MEASURE (S) Determining whether a majority of observed potential implant sites have 2, 3, or 4 mm of bone thickness while controlling for age differences and atresia status. RESULTS A total of 40 atretic (from 34 patients) and 34 control (from 34 patients) temporal bones were compared using CT. Likelihood ratio tests indicated that diagnosis did not have a statistically significant effect on whether patients reached thresholds of 2, 3, or 4 mm at most observed sites (p = 0.781, 0.773, and 0.529, respectively) when adjusting for age. For all children measured, 93% had >50% of measured points greater than or equal to 2 mm thick. CONCLUSION Most children had greater than 2 mm of temporal bone thickness at >50% of the sites measured regardless of age or atresia diagnosis. The likelihood of reaching 4 mm of thickness at most sites improves with age. In unilateral patients, there was not a significant difference in thickness between affected and unaffected sides. There was also no significant difference in thickness when comparing patients with atresia to those without.

BACKGROUND Diagnostic imaging is mandatory for the assessment of osseous defects in the jaws. Traditional imaging has offered much over the decades in the evaluation of these defects but is limited because of its 2D nature. The introduction of cone beam computed tomography (CBCT), a 3D radiographic technique with interactivity, high resolution, and high accuracy, has provided solutions in the evaluation of such lesions OBJECTIVE(S) The purpose of this in vitro investigation was to evaluate the accuracy of representation of experimental surgical defects with CBCT using different exposure parameters. Moreover, the study aims to assess the effect of different exposure protocols on the accuracy of representation of experimental surgical defects. STUDY DESIGN Surgical defects were prepared in 8 pig jaw mandibular segments. The thickness of the cortical bone around the defects was measured in predetermined areas using the measurement tools of the CBCT software. In total, 48 locations were measured for bone thickness. The pig jaw specimens were imaged with 6 different exposure protocols created by altering voxel size, kilovoltage peak, and milliamperage. The measurements were made by 2 experienced examiners using the original scanner software. The evaluation of the surgical defects was completed in 4 rating sessions; a fifth rating session was included for intraobserver reliability assessment. RESULTS There were statistically significant differences in the estimation of cortical bone thickness around experimental surgical defects in certain sites among the variable exposure protocols; however, the differences were too small to be clinically important. The intra- and interobserver reliability values were very high, confirming the diagnostic value of CBCT in different exposure settings. DISCUSSION/CONCLUSIONS The accuracy of lineal cortical bone measurements with CBCT was high, even in lower dose protocols, a finding that is in line with the ALADA (as low as diagnostically acceptable) concept.