Does 3-dimensional facial attractiveness relate to golden ratio, neoclassical canons, 'ideal' ratios and 'ideal' angles?

BACKGROUND: The established recommendations and guidelines regarding ideal measurements for an attractive face are mostly based on data gathered among Caucasian population. The aim of this study was to examine the relationship between perception of 3-dimensional facial attractiveness and golden ratio, neoclassical canons, 'ideal' ratios and 'ideal' angles in Hong Kong Chinese. METHODS: Thirty 3-D photographs (15 males and 15 females) were shown to 101 laypersons and 60 patients seeking orthognathic treatment. The photographs were rated based on a 100 mm visual analogue scale (VAS) from 0 (very unattractive) to 100 (very attractive). RESULTS: More than half of the measurements (42/77) in females and thirty-two measurements in males were found to be significantly different from the ideal target value (p < 0.05) upon the comparison of the attractive faces with golden ratio, neoclassical canons, 'ideal' ratios and 'ideal' angles. Meanwhile, correlation tests between VAS scores and the parameters detected significant results (p < 0.05) in only six ratios, eight angles, one neoclassical canon and one proportion. CONCLUSIONS: Despite several renowned 'ideal' parameters of attractive faces that have been recommended in the literature, only a few of them were found to be significantly correlated with attractive faces in Hong Kong Chinese.

Facial profile study using 3-dimensional photographs to assess esthetic preferences of Hong Kong Chinese orthognathic patients and laypersons.

INTRODUCTION: This study was conducted to investigate and compare esthetic perceptions of different facial profiles among Hong Kong Chinese laypersons and patients scheduled for orthognathic treatment. METHODS: Two sets of 3-dimensional facial photographs (1 male and 1 female) each comprised 7 images that showed different dentoskeletal relations (ie, Class I, bimaxillary protrusion, bimaxillary retrusion, maxillary protrusion, maxillary retrusion, mandibular protrusion, and mandibular retrusion). The sets of photographs were shown to 101 laypersons (age, 28.87 ± 6.22 years) and 60 patients seeking orthognathic treatment (age, 27.12 ± 6.07 years). They rated their esthetic perceptions of the photographs on the basis of a 100 mm visual analog scale (VAS) from 0 (very unattractive) to 100 (very attractive). RESULTS: The dentoskeletal Class I facial profile was ranked as the most attractive profile. Female orthognathic judges selected the retrusive maxilla while male orthognathic judges and male and female laypersons ranked the mandibular protrusion profile as the least attractive profile for both females and males. A bimaxillary protrusive female profile was viewed as more attractive by the orthognathic male (P = 0.006) and female (P = 0.006) judges, compared with female layperson judges. After adjustment for age, no statistically significant interaction between sex and judges (P >0.10) for all VAS scores were detected. For the female bimaxillary protrusive profile, orthognathic patient judges assigned a mean VAS score of 9.174 points higher than layperson judges (95% confidence interval, 3.11-15.24; P = 0.003). CONCLUSION: Dentoskeletal Class I facial profile was generally considered the most attractive profile in both sexes; male and female orthognathic patients preferred a bimaxillary protrusive female profile. A concave facial profile was perceived as least attractive in both sexes.

Distraction Osteogenesis in a Tessier 6 Cleft After Fronto-Orbito-Zygomatic Osteotomy - A Case Report.

The Rationale: Craniofacial clefts are rare malformations. According to their localization, 15 types are classified. Patient Concerns: They referred to impaired eyelid function, lateral protection of the eye-bulb, and aesthetic appearance. Diagnosis: A three-dimensional-computerized tomography scan and a stereolithographic model led to the diagnosis of a rare intraorbital Tessier 6 cleft. Treatment: A newly designed lateral orbital rim osteotomy, presurgically simulated on a stereolithographic model, was performed to forward position the lateral orbital rims bilaterally by osteodistraction. Outcomes: Both lateral orbital rims were distracted anteriorly for around 12 mm over a period of 9 weeks, without any side effects to the patient. Take-away Lessons: In this intraorbital Tessier 6 cleft, an improved eyelid function with better lateral protection of the eye bulb and more favorable aesthetic appearance was achieved with this novel lateral orbital rim osteotomy.

Patient's satisfaction with facial appearance and psycho-social wellness after orthognathic surgery among Hong Kong Chinese using the FACE-Q.

PURPOSE: To assess and compare the changes in satisfaction with facial appearance and psycho-social well-being in dento-skeletal class II and III patients after orthognathic surgery with the FACE-Q among Hong Kong Chinese. METHODS: The questionnaires for thirteen orthognathic-relevant FACE-Q scales, translated into Cantonese and validated, were administered to Hong Kong Chinese patients before and after orthognathic surgery in the short- and long-term, respectively. The assessed scales were categorized into four main domains: satisfaction with facial appearance, quality of life, patient's experience of care, and adverse effects. RESULTS: Generally, highly significant (p < 0.001) improved FACE-Q scores were found in the long-term in the scales investigating the satisfaction with overall facial appearance, lower face and jawline, and chin. Although dento-skeletal class III patients demonstrated significantly improved satisfaction with their post-surgical nostril appearance (p = 0.003), this was not evident in dento-skeletal class II patients (p = 0.231). Nonetheless, both class II and class III subjects have also revealed significantly improved psychological well-being (0.003; <0.001) and social function (0.001; <0.001) in the long-term. Age was not found to be correlated with all scales for satisfaction of facial appearance. CONCLUSION: Previously validated Face-Q scales are valuable instruments to measure clinical outcomes, psychological well-being and social function in Cantonese speaking patients. Both Class II and Class III patients showed significantly improved satisfaction with facial appearance, psychological well-being and social function after orthognathic surgery regardless of skeletal pattern and gender, confirming findings in other ethnicities.

Holoprosencephaly with Clefts: Data of 85 Patients, Treatment, and Outcome: Part 2: Management, Surgical Treatment, and Unexpected Aspects of Holoprosencephaly Cleft Patients.

CONTEXT: Cleft patients with holoprosencephaly (HPE) provide a wide clinical spectrum. Besides accessory agenesis of facial tissue structures, spanning from a single central incisor to the columella, up to the entire prolabium-premaxilla complex, brain deformities with various functional deficits may prevail, just like normal brain development. Making a precise diagnosis, just like choosing the most appropriate treatment plan often is challenging. A literature and chart review comprising 85 HPE cleft cases at the Cleft Clinic of the University of Pretoria, South Africa, was performed. It yielded pertinent diagnostic criteria and collected information about pregnancy history, brain development and survival rate as well as the initial perioperative management and the course of postsurgical midfacial growth. AIMS OF PART 2: The aim is to highlight how the here presented classification system of HPE cleft patients according to their clinical picture may facilitate the most appropriate treatment protocol. MATERIALS AND METHODS: The classification system elaborated in Part I due to diagnostic criteria facilitated establishing classification related treatment protocol for 85 cleft cases with HPE. RESULTS: According to diagnostic criteria, HPE cleft cases can be subdivided into (1) columella complex agenesis (Ag-Colum), (2) prolabium-premaxilla-columella complex agenesis in cleft lip-alveolus deformities (Ag-CLA), (3) prolabium-premaxilla-columella complex agenesis in complete hard and soft palate clefts (Ag-CLAP), and (4) "standard" uni-or bilateral CLA or CLAP (HPE-Std-cleft), including cases with an atrophic premaxilla with or without single central incisors. Relevant treatment protocols according to the particular classification are highlighted with figures and intra-operative pictures. CONCLUSION: This paper addresses the following aspects in cleft patients with HPE: A subdivision into four groups, the 3-in-1 surgical approach, the anteriorly directed midfacial growth and maternal HIV infection.

Holoprosencephaly with Clefts: Data of 85 Patients, Treatment and Outcome: Part 1: History, Subdivisions, and Data on 85 Holoprosencephalic Cleft Patients.

CONTEXT: Cleft patients with Holoprosencephaly (HPE) constitute a controversy due to a variable facial appearance. HPE appearance varies from only a columella to a prolabium-premaxilla complex agenesis up to a common unilateral or bilateral cleft lip and palate with a single central incisor, various brain deformities, and/or even normal brain development. It is challenging to designate such various appearances, to understand their etiopathogenesis, and to choose the most appropriate management. Literature was reviewed for diagnostic criteria, pregnancy history, clinical findings, brain development, survival rate, initial perioperative management, and postsurgical midfacial growth in cleft patients with HPE. The findings were compared with a clinical database of 85 cleft patients with HPE at the Department of Maxillofacial and Oral Surgery, University of Pretoria. AIMS OF PART 1: The aim of the study is to overcome disparities widely existing among clinicians regarding definitive diagnostic criteria, especially in cases with a common appearance of a uni- or bilateral cleft lip alveolus or cleft lip, alveolus and palate deformity, and cases presenting facial structural agenesis. MATERIALS AND METHODS: A literature search related to diagnostic criteria was compared to results of a cleft HPE database from a single tertiary institution. RESULTS: HPE cleft cases can be allocated to one of the following subdivisions: (1) columella complex agenesis (Ag-Colum), (2) prolabium-premaxilla-columella complex agenesis in cleft lip-alveolus deformities (Ag-CLA), (3) prolabium-premaxilla-columella agenesis in cases with complete cleft lip alveolus palate (Ag-CLAP), and (4) standard type (holoprosencephaly in patients with a standard cleft) with uni- or bilateral CLA or CLAP, hard and soft palate cleft (hPsP), and atrophic premaxillae, with or without single central incisor. Further, incidence, variation in brain development, and appearances in HPE cleft patients of different races and gender, epilepsy, and early death are discussed. Conclusion: This paper adds new data and facts to the existing literature related to cleft lip and palate patients suffering from HPE.

Three-Dimensional Pharyngeal Airway Changes After 2-Jaw Orthognathic Surgery With Segmentation in Dento-Skeletal Class III Patients.

PURPOSE: To investigate short- and long-term three-dimensional changes of pharyngeal airway morphology and hyoid bone position in dento-skeletal class III deformity patients after 2-jaw orthognathic surgery with segmentation. METHODS: A retrospective analysis has been performed on patients with dento-skeletal class III deformity who had undergone orthognathic 2-jaw surgery with segmentations, presenting both pre- and post-surgical cone-beam computed tomographys. Three-dimensional skeletal movements, pharyngeal airway changes and hyoid bone position were measured and correlated. RESULTS: The mean short term postsurgical review period for all included 47 patients was 5.8 ±â€Š2.2 months. Thirteen patients among them provided a mean long term period of 26.4 ±â€Š3.4 months. The mean postsurgical maxillary movement was 2.29 ±â€Š2.49 mm in vertical, 2.02 ±â€Š3.45 mm in horizontal direction, respectively, while the mandibular movement was 6.49 ±â€Š4.58 mm in vertical, and -5.85 ±â€Š6.13 mm in horizontal direction. In short-term, the vertical length of nasopharynx was found to be reduced (P = 0.005) but increased for the oropharynx (P < 0.001). Furthermore, the oropharyngeal minimum cross-sectional area has decreased significantly (P = 0.013). The hyoid bone moved posterosuperiorly, however, with only its horizontal movement found to be significant (P = 0.043). No significant result was detected in long-term analyses, neither in postsurgical pharyngeal airway changes nor the hyoid bone movement. There were no significant differences in pharyngeal airway measurements (P > 0.05) detected between patients with and without genioplasty advancement. CONCLUSION: Two-jaw orthognathic surgery in dento-skeletal class III patients led to a statistically non-significant reduction of the post-surgical airway volume in both short- and long-term. Although the post-surgical oropharyneal minimum cross-sectional area was decreased significantly in the short term, this finding did not persist in the long term.

Differences between epithelial and mesenchymal human tongue cancer cell lines in experimental metastasis.

Distant metastasis represents the outcome with the worst prognosis for various types of malignant tumors, but little is known regarding the impact of interacting epithelial and mesenchymal phenotypic cancer cells within its etiopathogenesis. In a novel animal model, 48 male athymic Balb/c nude mice underwent subcutaneous and intravenous injection of human tongue cancer cell lines of green fluorescent mesenchymal and red fluorescent epithelial phenotypes, in order to visualize and monitor eventual phenotypic interaction in lung metastasis as well as experimental metastasis in in vivo, ex vivo and histopathological analyses. While the epithelial, but not the mesenchymal, phenotypic human tongue cancer cell line led to direct metastasis in the lungs when injected intravenously, neither of them, even when injected in combination, were able to establish distant metastasis. The results of the present study provide evidence regarding the role of epithelial phenotypic cancer cells in the release of experimental metastasis following tail vein injection in male athymic Balb/c nude mice, in addition to proving fluorescent human tongue cancer cells may be reliably detected under a fluorescence microscope even 8 weeks after the two injection types.

Effects of mandibular setback with or without maxillary advancement osteotomies on pharyngeal airways: An overview of systematic reviews.

BACKGROUND: Mandibular setback osteotomies potentially lead to narrowing of the pharyngeal airways, subsequently resulting in post-surgical obstructive sleep apnea (OSA). OBJECTIVE: To summarize current evidence from systematic reviews that has evaluated pharyngeal airway changes after mandibular setback with or without concomitant upper jaw osteotomies. METHODOLOGY: PubMed, EMBASE, Web of Science, and Cochrane Library databases were searched with no restriction of language or date. Systematic reviews studying changes in pharyngeal airway dimensions and respiratory parameters after mandibular setback with or without concomitant upper jaw osteotomies have been identified, screened for eligibility, included and analyzed in this study. RESULTS: Six systematic reviews have been included. While isolated mandibular setback osteotomies result in reduced oropharyngeal airway dimensions, the reduction is lesser in cases with concomitant upper jaw osteotomies. Only scarce evidence exists currently to what happens to naso- and hypo-pharyngeal airways. There is no evidence for post-surgical OSA, even though some studies reported reduced respiratory parameters after single-jaw mandibular setback with or without concomitant upper jaw osteotomies. CONCLUSION: Although mandibular setback osteotomies reduce pharyngeal airway dimensions, evidence confirming post-surgical OSA was not found. Nevertheless, potential post-surgical OSA should be taken into serious consideration during the treatment planning of particular orthognathic cases. As moderate evidence exists that double-jaw surgeries lead to less compromised post-surgical pharyngeal airways, they should be considered as the method of choice especially in cases with severe dentoskeletal Class III deformity. STUDY REGISTRATION: PROSPERO (registration number: CRD42016046484).

How does mandibular advancement with or without maxillary procedures affect pharyngeal airways? An overview of systematic reviews.

BACKGROUND: Mandibular advancement surgery may positively affect pharyngeal airways and therefore potentially beneficial to obstructive sleep apnea (OSA). OBJECTIVE: To collect evidence from published systematic reviews that have evaluated pharyngeal airway changes related to mandibular advancement with or without maxillary procedures. METHODOLOGY: PubMed, EMBASE, Web of Science, and Cochrane Library were searched without limiting language or timeline. Eligible systematic reviews evaluating changes in pharyngeal airway dimensions and respiratory parameters after mandibular advancement with or without maxillary surgery were identified and included. RESULTS: This overview has included eleven systematic reviews. Maxillomandibular advancement (MMA) increases linear, cross-sectional plane and volumetric measurements of pharyngeal airways significantly (p<0.0001), while reducing the apnea-hypopnea index (AHI) and the respiratory disturbance index (RDI) significantly (p<0.0001). Two systematic reviews included primary studies that have evaluated single-jaw mandibular advancement, but did not discuss their effect onto pharyngeal airways. Based on the included primary studies of those systematic reviews, single-jaw mandibular advancement was reported to significantly increase pharyngeal airway dimensions (p<0.05); however, conclusive long-term results were lacking. CONCLUSION: MMA increases pharyngeal airway dimensions and is beneficial to patients suffering from OSA. However, more evidence is still needed to draw definite conclusion related to the effect of single-jaw mandibular advancement osteotomies on pharyngeal airways.

Evidence of phenotypic stability after transduction of fluorescent proteins in two human tongue cancer cell lines.

OBJECTIVES: This study investigated the phenotypic stability and biological properties of two human tongue cancer cell lines after transduction of fluorescent proteins. DESIGN: The human tongue cancer cell lines UM1 and UM2 were cultured with GFP and RFP lentiviral particles stock for 72h. Cells with successful transduction of fluorescent proteins were selected in a medium containing G418 antibiotics for two weeks. The proliferation rates of parental and transduced cell lines were evaluated by their population doubling time (PDT). Transduction efficiency was assessed by fluorescence microscope and flow cytometry. The transduced cells in passage 1, 2, 10, 20 and 30 were collected to check the stability of fluorescent protein expression. Phenotypic stability of the transduced cells was detected by means of cell morphology, cell surface markers and cell function evaluating essay. RESULTS: The proliferation rates of the transduced cell lines showed no significant difference compared to their parental cells. Successful transduction with high efficiency (99% up) was demonstrated. High fluorescence expression on both transduced cells was detected until the thirtieth generation. UM1 and UM1-GFP displayed mesenchymal cell characteristics, while UM2 and UM2-RFP cell lines showed properties characteristic of epithelial. CONCLUSIONS: Two human tongue cancer cell lines of epithelial and mesenchymal phenotype respectively, have been successfully labelled with green and red fluorescent proteins. The fluorescence maintained a high expression rate over thirty generations without influencing the original morphological phenotype and cadherin expression.

Orthognathic Relevant Scales of FACE-Q: Translation and Validation for Hong Kong Chinese Patients.

BACKGROUND: A validated questionnaire is needed to study a more holistic outcome assessment including postsurgical aesthetic satisfaction and psychosocial changes in orthognathic patients. The aim of this study was to determine the reliability and validity of 9 orthognathically relevant translated FACE-Q scales among Hong Kong Chinese orthognathic patients. METHODS: Two hundred fifty adult Cantonese-speaking patients of 18 years or older who underwent orthognathic treatment were recruited in the Prince Philip Dental Hospital of Hong Kong. Nine of an overall of 40 independent FACE-Q scales were selected and translated into Hong Kong Chinese. The reliability, validity, and test-retest reliability were examined using Cronbach's alpha, paired t test and Pearson's correlation coefficients. RESULTS: The Hong Kong Chinese version of the 9 FACE-Q scales was obtained by forward-backward translation. One hundred eight male (mean age, 25.57 ± 4.49) and 142 female (mean age, 24.61 ± 4.54) patients were recruited for the reliability and validation process. The internal consistency (0.89-0.97) and the test-retest reliability (0.73-0.90) were found to be high. The validity of the translated questionnaires was comparable with that of the original FACE-Q. CONCLUSION: The results presented here prove that the 9 translated FACE-Q scales are reliable and valid instruments for research and clinical purposes in Hong Kong Chinese orthognathic patients.

Tumorigenicity and Validity of Fluorescence Labelled Mesenchymal and Epithelial Human Oral Cancer Cell Lines in Nude Mice.

Tumorigenicity and metastatic activity can be visually monitored in cancer cells that were labelled with stable fluorescence. The aim was to establish and validate local and distant spread of subcutaneously previously injected fluorescence transduced human tongue cancer cell lines of epithelial and mesenchymal phenotype in nude mice. A total of 32 four-week-old male athymic Balb/c nude mice were randomly allocated into 4 groups (n = 8). A single dose of 0.3 mL PBS containing 1 × 107 of four different cancer cell-lines (UM1, UM1-GFP, UM2, and UM2-RFP) was injected subcutaneously into the right side of their posterolateral back. Validity assessment of the labelled cancer cells' tumorigenicity was assessed by physical examination, imaging, and histology four weeks after the injection. The tumor take rate of cancer cells was similar in animals injected with either parental or transduced cancer cells. Transduced cancer cells in mice were easily detectable in vivo and after cryosection using fluorescent imaging. UM1 cells showed increased tumor take rate and mean tumor volume, presenting with disorganized histopathological patterns. Fluorescence labelled epithelial and mesenchymal human tongue cancer cell lines do not change in tumorigenicity or cell phenotype after injection in vivo.

Pierre Robin sequence: Subdivision, data, theories, and treatment - Part 1: History, subdivisions, and data.

CONTEXT: The disorder currently accepted as Pierre Robin syndrome/anomaly/sequence (PRS) has been plagued by controversy ever since initially being described. Controversy exists not only about the appropriate terminology and etiopathogenesis of the disorder but also about its management. Therefore, clinical findings and treatment outcomes of a large database of 266 PRS cases were compared with the current state of knowledge in scientific literature related to history, clinical description, diagnostic criteria, epidemiology, theories of oligohydramnios, mandibular catch-up growth, midfacial hyperplasia, and the timing of management. AIMS OF PART 1: Display disparities of the widely published subject of PRS that exist within the literature. SUBJECTS AND METHODS: A literature search related to diagnostic criteria was compared to findings of one of the largest PRS databases worldwide. RESULTS: Regarding diagnostic criteria two subdivisions, the Fairbairn-Robin triad (FRT) and the Siebold-Robin sequence (SRS) can be clearly distinguished. Both present with micrognathia and glossoptosis, the former with, the latter, however, without a palatal cleft. CONCLUSIONS: According to clear diagnostic criteria, PRS has to be subdivided in the future into FRT and SRS cases, as they may require different treatment approaches.

Pierre Robin sequence: Subdivision, data, theories, and treatment - Part 2: Syndromic and nonsyndromic Pierre Robin sequence.

CONTEXT: The disorder currently accepted as Pierre Robin syndrome/anomaly/sequence (PRS) has been plagued by controversy ever since initially being described. Controversy exists not only about the appropriate terminology and etiopathogenesis of the disorder but also about its management. Clinical findings and treatment outcomes of a large database of 266 PRS cases were compared with the current state of knowledge in the scientific literature, relating to history, clinical description, diagnostic criteria, epidemiology, theories of oligohydramnios, mandibular catch-up growth, midfacial hyperplasia, and the early management. AIMS OF PART 2: Contribute to the sparse scientific knowledge about pathogenesis and involved genetics. SUBJECTS AND METHODS: An analysis of this large database was conducted focusing on genetic involvement, family history, and the incidence of additional syndromes. RESULTS: Beside of differences related to clinical signs of dyspnea, feeding problems and mortality rates, various concomitant syndromes, and genetic abnormalities were found in cases of Fairbairn-Robin triad (FRT) and Siebold-Robin sequence (SRS), in addition to differences in relation to clinical signs of dyspnea, feeding problems, and mortality rates. CONCLUSION: Multiple FRT cases presented with various concomitant syndromes and genetic abnormalities, but only one type occurred in two SRS cases. The latter presented a significantly different mortality rate when compared to the FRT subgroup.

Pierre Robin sequence: Subdivision, data, theories, and treatment - Part 3: Prevailing controversial theories related to Pierre Robin sequence.

CONTEXT: The disorder currently accepted as Pierre Robin syndrome/anomaly/sequence (PRS) has been plagued by controversy ever since initially being described. Controversy exists not only about the appropriate terminology and etiopathogenesis of the disorder but also about its management. Therefore, clinical findings and treatment outcomes of a large database of 266 PRS cases were compared with the current state of knowledge in the scientific literature related to history, clinical description, diagnostic criteria, epidemiology, theories of oligohydramnios, mandibular catch-up growth, midfacial hyperplasia, and the early management. AIM: The aims of Part 3 debate the controversial biological theories relating to PRS. MATERIALS AND METHODS: Oligo-/poly-hydramnios, mandibular catch-up growth, and midfacial hyperplasia, the three in the literature most prevailing theories related to PRS, have been compared and discussed with the findings provided by this large database of 266 Siebold-Robin sequence (SRS) and Fairbairn-Robin triad (FRT) cases. RESULTS: History and clinical findings evaluated in this database refute the first two theories. Although manifold midfacial appearances were demonstrated in FRT cases, a third of all SRS cases presented with mid-facial hyperplasia. CONCLUSION: The three main biological theories regarding PRS could not be verified after thorough analysis of the database.

Pierre Robin sequence: Subdivision, data, theories, and treatment - Part 4: Recommended management and treatment of Pierre Robin sequence and its application.

CONTEXT: The disorder currently accepted as Pierre Robin syndrome/anomaly/sequence (PRS) has been plagued by controversy ever since initially being described. Controversy exists not only about the appropriate terminology and etiopathogenesis of the disorder but also about its management. Therefore, clinical findings and treatment outcomes of a large database of 266 PRS cases were compared with the current state of knowledge in the scientific literature related to history, clinical description, diagnostic criteria, epidemiology, theories of oligohydramnios, mandibular catch-up growth, midfacial hyperplasia, and early management. AIMS OF PART 4: To provide a systematic treatment protocol for Fairbairn-Robin triad (FRT) and Siebold Robin sequence (SRS) patients based on clinical findings and experience with 266 PRS cases. SUBJECTS AND METHODS: A plethora of treatment modalities and their outcome in literature have been compared to those applied in this database and their outcomes. RESULTS: The management of SRS/FRT depends on various factors including compromised airways, feeding difficulties, as well as the sequence of the reconstructive ladder. CONCLUSION: Based on the novel PRS subdivisions, a stepwise sequential treatment approach is outlined, addressing the particular needs of each disorder systematically.

The Oropharyngeal Airway in Young Adults with Skeletal Class II and Class III Deformities: A 3-D Morphometric Analysis.

OBJECTIVES: 1) To determine the accuracy and reliability of an automated anthropometric measurement software for the oropharyngeal airway and 2) To compare the anthropometric dimensions of the oropharyngeal airway in skeletal class II and III deformity patients. METHODS: Cone-beam CT (CBCT) scans of 62 patients with skeletal class II or III deformities were used for this study. Volumetric, linear and surface area measurements retroglossal (RG) and retropalatal (RP) compartments of the oropharyngeal airway was measured with the 3dMDVultus software. Accuracy of automated anthropometric pharyngeal airway measurements was assessed using an airway phantom. RESULTS: The software was found to be reasonably accurate for measuring dimensions of air passages. The total oropharyngeal volume was significantly greater in the skeletal class III deformity group (16.7 ± 9.04 mm3) compared with class II subjects (11.87 ± 4.01 mm3). The average surface area of both the RG and RP compartments were significantly larger in the class III deformity group. The most constricted area in the RG and RP airway was significantly larger in individuals with skeletal class III deformity. The anterior-posterior (AP) length of this constriction was significantly greater in skeletal class III individuals in both compartments, whereas the width of the constriction was not significantly different between the two groups in both compartments. The RP compartment was larger but less uniform than the RG compartment in both skeletal deformities. CONCLUSION: Significant differences were observed in morphological characteristics of the oropharyngeal airway in individuals with skeletal class II and III deformities. This information may be valuable for surgeons in orthognathic treatment planning, especially for mandibular setback surgery that might compromise the oropharyngeal patency.

Role of periodontal disease in bisphosphonate-related osteonecrosis of the jaws in ovariectomized rats.

OBJECTIVE: This study aimed to investigate the role of progressive periodontal disease in inducing bisphosphonate-related osteonecrosis of the jaws (BRONJ) using an ovariectomized (OVX) rat model mimicking human intracortical remodeling process. MATERIALS AND METHODS: Thirty 12-week-old Spraque-Dawly (SD) female rats were randomly assigned into two groups. All rats underwent bilateral ovariectomy. Six weeks after surgery, zoledronic acid (ZA) or vehicle control was administered intraperitoneally for 12 weeks. On the same day of injection, a cotton ligature was placed subgingivally around the first left lower molar to induce periodontitis. All animals were sacrificed 12 weeks after injection. The entire mandibles were harvested for micro-computed tomography (micro-CT) and histological examinations. RESULTS: Micro-CT examination showed that ligature placement caused significant alveolar bone loss both in ZA (0.63 ± 0.13 vs. 0.38 ± 0.06 mm, P < 0.001) and in control (0.88 ± 0.19 vs. 0.40 ± 0.06 mm, P < 0.001) groups. Whereas in the ZA group, bone loss was attenuated compared with the control group (P < 0.01); the bone mineral density in the ZA group (1.00 ± 0.02 g/cm(3)) was significantly higher than that in vehicle control group (0.96 ± 0.03 g/cm(3), P < 0.001). Histological examination found necrotic bone tissue with extensive, empty lacunae in two of 15 rats in ZA group, but in none of the control group. CONCLUSION: Bisphosphonates inhibit alveolar bone resorption in progressive periodontal disease, which might benefit the management of periodontitis, but increase the risk of developing BRONJ.

EPA-coated titanium implants promote osteoconduction in white New Zealand rabbits.

OBJECTIVES: To investigate the effect of eicosapentaenoic acid (EPA)-coated Ti implants on osteoconduction in white New Zealand rabbit mandibles. MATERIAL AND METHODS: Sandblasted and cleansed planar titanium specimens with a size of 5 × 5 × 1 mm were coated on one side with 0.25 vol% eicosapentaenoic acid (EPA). The other side of the specimens was kept highly polished (the control side). These specimens were inserted in rabbit mandibles. Twelve rabbits were randomly assigned into three study groups (n = 4). The rabbits were sacrificed at 4, 8, and 12 weeks. The harvested specimens with the implants were assessed for new bone formation on both sides of the implant using CBCT, conventional radiographs, and the biaxial pullout test. The results were statistically analyzed by a nonparametric Kruskal-Wallis test and Friedman's test as multiple comparisons and by Brunner-Langer nonparametric mixed model approach (R Software). RESULTS: A significant osteoconductive bone formation was found on the EPA-coated Ti implant surface (P < 0.05) at 8 weeks when compared to the polished surface (control). Biaxial pullout test results showed a significant difference (P < 0.05) after 8 and 12 weeks with a maximum force of 243.8 N, compared to 143.25 N after 4 week. CONCLUSION: EPA implant coating promoted osteoconduction on the Ti implant surfaces, enhancing the anchorage of the implant to the surrounding bone in white New Zealand rabbits.